WorldWideScience

Sample records for basin northern brazil

  1. A new species of Bryconops (Teleostei: Characidae from the rio Madeira basin, Northern Brazil

    Directory of Open Access Journals (Sweden)

    Juliana M. Wingert

    Full Text Available A new species of Bryconops is described from a tributary to the rio Madeira in the Amazon basin, State of Rondônia, Brazil. Bryconops piracolina belongs to the subgenus Bryconops by having no teeth or rarely one tooth in the maxilla, and a naked area on cheek between the second and third infraorbitals. The new species is distinguished from all species of this subgenus by the presence of a large black blotch on dorsal-fin base. Furthermore, it is distinguished from all congeners, except B. inpai, by possessing the adipose fin entirely black. It differs from B. inpai by the lack of humeral spots. It further differs from all species of the subgenus Bryconops, except B. caudomaculatus, by having the last scales of the longitudinal series of scales that bears the lateral line series not pored beyond the end of the hypural plate, and differs from B. caudomaculatus by the smaller number of pored lateral line scales (31-36, mean 34.6, vs. 37-43, mean = 40.6, respectively.

  2. Lower Permian stems as fluvial paleocurrent indicators of the Parnaíba Basin, northern Brazil

    Science.gov (United States)

    Capretz, Robson Louiz; Rohn, Rosemarie

    2013-08-01

    A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit "Tocantins Fossil Trees Natural Monument". In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes, which sometimes hold, almost adjacent to the lateral stem surface, permineralized fern pinnae and other small plant fragments. In the more central site, 82 measured stems are preferentially oriented in the SW-NE direction, the proportion of gymnosperms is higher and cross-stratification sets of sandstones indicate paleocurrents mainly to NE and secondarily to SE. In the western site, most of the 42 measured stems lie in E-W positions. The predominantly sandy succession, where the fossil stems are best represented, evidences a braided fluvial system under semiarid conditions. The low plant diversity, some xeromorphic features and the supposedly almost syndepositional silica impregnation of the plants are coherent with marked dry

  3. Tectonics and paleogeography of the Marajó Basin, northern Brazil

    Directory of Open Access Journals (Sweden)

    JOÃO B. S. COSTA

    2002-09-01

    Full Text Available The Marajó Basin area presents geologic and geomorphologic features chiefly due to the Mesozoic extension and post-Miocene neotectonics. The extension event with an Early and a Late Cretaceous phases originated four sub-basins that constitutes the Marajó Basin, with a thick continental clastic sequence showing marine influence. NW and NNW normal faults and NE and ENE strike-slip faults controlled the basin geometry. The extension, related to the Equatorial Atlantic opening, propagated into the continent along crustal weakness zones of the Precambrian Tumucumaque, Amapá and Araguaia orogenic belts. The neotectonic event is a strike-slip regime which developed transtensional basins filled in by Upper Tertiary shallow marine (Pirabas Formation and transitional sequences (Barreiras Group, followed by Quaternary fluvial deposits and transitional sequences derived from the Amazon and Tocantins rivers and the Marajoara estuary. The current landscape has a typical estuarine morphology. The coast morphology presents sea-cliffs on transitional Upper Tertiary sequences, while inwards dominate hills sustained by Mid-Pleistocene lateritic crust, with a flat erosive surface at 70 m. In the eastern Marajó Island several generations of paleochannels associated with fluvial-estuarine sequences are recognized, while a fluvial-marine plain is widespread on its western side.A área da Bacia do Marajó apresenta feições geológicas e geomorfológicas devidas principamente à distensão Mesozóica e à neotectônica pós-miocênica. O evento de distensão, com fases do Cretáceo Inferior e Superior, originou quatro sub-bacias que contituem a Bacia do Marajó, com uma espessa seqüência clástica continental mostrando influência marinha. Falhas normais NW e NNW e direcionais NE e ENE controlaram a geometria da bacia. A distensão, relacionada com a abertura do Atlântico Equatorial, propagou-se continente adentro ao longo de zonas de fraqueza crustal dos

  4. Aquatic life protection index of an urban river Bacanga basin in northern Brazil, São Luís - MA

    Directory of Open Access Journals (Sweden)

    A. K. Duarte-dos-Santos

    Full Text Available Abstract Bacanga River Basin faces environmental problems related to urbanization and discharge of untreated domestic sewage, which compromise its ecosystem health. Due to the small number of studies that assessed its water quality, the present study aimed to assess the current status of this ecosystem based on the aquatic life protection index. Samples were carried out every two months, in a total of six events, in six sites along the basin, where the water samples were collected to assess physicochemical parameters and calculate the trophic state index and the index of minimum parameters for the protection of aquatic communities. The data were also compared with values determined by the resolution National Environment Council - CONAMA 357/05. Our results reveal significant changes in the water quality of Bacanga River Basin. An increase in nutrients and chlorophyll-a concentration led it to eutrophication. The surfactant values were high and put in danger the aquatic biota. Dissolved oxygen rates were below the values allowed by the resolution in most sites sampled. The current water quality is terrible for the protection of aquatic life in 61.92% of the sites sampled.

  5. Salt tectonics in Santos Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Quirk, David G.; Nielsen, Malene; Raven, Madeleine [Maersk Oil and Gas, Copenhagen (Denmark); Menezes, Paulo [Maersk Oil and Gas, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    From Albian to end Cretaceous times, the inboard part of the Santos Basin in Brazil was affected by extension as salt flowed basinwards under the effect of gravity. Salt rollers, flip-flop salt diapirs and the famous Albian Gap were all formed by this process. Outboard of these extensional structures, contraction was taken up in a wide zone of thickened salt where salt collected. The overburden was carried on top of the salt as it flowed down-dip, with up to 40 km of translation recorded in Albian strata. (author)

  6. Groundwater quality in the Northern Coast Ranges Basins, California

    Science.gov (United States)

    Mathany, Timothy M.; Belitz, Kenneth

    2015-01-01

    The Northern Coast Ranges (NOCO) study unit is 633 square miles and consists of 35 groundwater basins and subbasins (California Department of Water Resources, 2003; Mathany and Belitz, 2015). These basins and subbasins were grouped into two study areas based primarily on locality. The groundwater basins and subbasins located inland, not adjacent to the Pacific Ocean, were aggregated into the Interior Basins (NOCO-IN) study area. The groundwater basins and subbasins adjacent to the Pacific Ocean were aggregated into the Coastal Basins (NOCO-CO) study area (Mathany and others, 2011).

  7. Uranium deposits: northern Denver Julesburg basin, Colorado

    International Nuclear Information System (INIS)

    Reade, H.L.

    1978-01-01

    The Fox Hills Sandstone and the Laramie Formation (Upper Cretaceous) are the host rocks for uranium deposits in Weld County, northern Denver Julesburg basin, Colorado. The uranium deposits discovered in the Grover and Sand Creek areas occur in well-defined north--south trending channel sandstones of the Laramie Formation whereas the sandstone channel in the upper part of the Fox Hills Sandstone trends east--west. Mineralization was localized where the lithology was favorable for uranium accumulation. Exploration was guided by log interpretation methods similar to those proposed by Bruce Rubin for the Powder River basin, Wyoming, because alteration could not be readily identified in drilling samples. The uranium host rocks consist of medium- to fine-grained carbonaceous, feldspathic fluvial channel sandstones. The uranium deposits consist of simple to stacked roll fronts. Reserve estimates for the deposits are: (1) Grover 1,007,000 lbs with an average grade of 0.14 percent eU 3 O 8 ,2) Sand Creek 154,000 lbs with an average grade of 0.08 percent eU 3 O 8 , and 3) The Pawnee deposit 1,060,000 lbs with an average grade of 0.07 percent eU 3 O 8 . The configuration of the geochemical cells in the Grover and Sand Creek sandstones indicate that uraniferous fluids moved northward whereas in the Pawnee sandstone of the Fox Hills uraniferous fluids moved southward. Precipitation of uranium in the frontal zone probably was caused by downdip migration of oxygcnated groundwater high in uranium content moving through a favorable highly carbonaceous and pyritic host sandstone

  8. Northern part, Ten Mile and Taunton River basins

    Science.gov (United States)

    Williams, John R.; Willey, Richard E.

    1967-01-01

    The northern part of the Ten Mile and Taunton River basins is an area of about 195 square miles within Norfolk, Plymouth, and Bristol Counties in southeastern Massachusetts. The northern boundary of the area (plate 1) is the drainage divide separating these basins from that of the Charles, Neponset, and Weymouth River basins. The western boundary is, for the most part, the divide separating the basins from the Blackstone River basin. The eastern boundary is at the edge of the Brockton-Pembroke area (Petersen, 1962; Petersen and Shaw, 1961). The southern boundary in Seekonk is the northern limit of the East Providence quadrangle, for which a ground-water map was prepared by Allen and Gorman (1959); eastward, the southern boundaries of the city of Attleboro and the towns of Norton, Easton, and West Bridgewater form the southern boundary of the area.

  9. Geomorphological characterization of endorheic basins in northern Chile

    Science.gov (United States)

    Dorsaz, J.; Gironas, J. A.; Escauriaza, C. R.; Rinaldo, A.

    2011-12-01

    Quantitative geomorphology regroups a large number of interesting tools to characterize natural basins across scales. The application of these tools to several river basins allows the description and comparison of geomorphological properties at different spatial scales as oppose to more traditional descriptors that are typically applied at a single scale, meaning the catchment scale. Most of the recent research using these quantitative geomorphological tools has focused on open catchments and no specific attention has been given to endorheic basins, and the possibility of having particular features that distinguish them from exorheic catchments. The main objective of our study is to characterize endorheic basins and investigate whether these special geomorphological features can be identified. Because scaling invariance is a widely observed and relatively well quantified property of open basins, it provides a suitable tool to characterize differences between the geomorphology of closed and open basins. Our investigation focuses on three closed basins located in northern Chile which describe well the diversity in the geomorphology and geology of this arid region. Results show that endhoreic basins exhibit different slope-area and flow paths sinuosity regimes compared to those observed in open basins. These differences are in agreement with the particular self-similar behavior across spatial scales of the Euclidean length of subcatchments, as well as the Hack's law and Horton's ratios. These regimes imply different physical processes inside the channel network regardless of the basin area, and they seem to be related to the endorheic character of these basins. The analysis of the probability density functions of contributing areas and lengths to the lower region shows that the hypothesis of self-similarity can also be applied to closed basins. Theoretical expressions for these distributions were derived and validated by the data. Future research will focus on (1

  10. Squamate reptiles of the Atlantic Forest of northern Bahia, Brazil

    OpenAIRE

    de Freitas, Marco

    2014-01-01

    We present a list of squamate reptiles of the northern Atlantic forest of Bahia, Brazil, comprising a total of 29 municipalities. The study area was sampled opportunistically over more than 20 years resulting in a total of 482 specimens deposited in various herpetological collections. Of these, 314 were snakes belonging to 62 species and seven families, 42 were amphisbaenas belonging to five species in a single family and 125 specimens were lizards, grouped in 36 species and 12 families.

  11. First isolation of enterovirus 71 (EV-71 from Northern Brazil

    Directory of Open Access Journals (Sweden)

    Lamarão Leticia Martins

    2003-01-01

    Full Text Available Enterovirus 71 (EV-71 has been associated to cases of neurological disease in many countries including Brazil. This virus has now been reported from three of the five Brazilian regions. Our study relates the findings concerning to the first isolate of this virus in Northern region of Brazil. A 15-month old female patient, from the rural zone of the municipality of Santana do Araguaia in southern Pará state was admitted at the hospital with acute, flaccid, asymmetric and ascending motor deficiency, located in the right lower limb. Stools samples from this child were inoculated in RD cells and was isolated an EV-71. We plan to sequence our strain and compare it to other isolates in Brazil. Differences at the molecular level can explain why EV-71 strains circulating in other continents, such as Asia, appear to be more virulent.

  12. Northern Rivers Basins human health monitoring program : report

    International Nuclear Information System (INIS)

    Gabos, S.

    1999-04-01

    The Northern River Basins Human Health Monitoring Program was established in 1994 to investigate the possible relationships between various environmental risk factors and the health of northern residents in the province. This report presents the initial analysis of the health program and examines the differences in health outcomes across the province and compares the Northern Rivers Basin Study (NRBS) area with the other areas of the province. A series of maps and graphs showed the prevalence of certain diseases and disorders within the Peace and Athabasca river basins. The focus of the report was on reproductive health, congenital anomalies, respiratory ailments, circulatory diseases, gastrointestinal disorders, endocrine and metabolic disorders, and neurocognitive disorders. The study showed that compared to other areas of the province, the NRBS area had higher incidences of endometriosis, selected congenital anomalies, bronchitis, pneumonia, peptic ulcers and epilepsy. There were three potential exposure pathways to environmental contaminants. These were through ingestion of water or food, inhalation of air and through dermal exposure. refs., tabs., figs

  13. Northern Rivers Basins human health monitoring program : report

    Energy Technology Data Exchange (ETDEWEB)

    Gabos, S. [Alberta Health, Edmonton, AB (Canada). Health Surveillance

    1999-04-01

    The Northern River Basins Human Health Monitoring Program was established in 1994 to investigate the possible relationships between various environmental risk factors and the health of northern residents in the province. This report presents the initial analysis of the health program and examines the differences in health outcomes across the province and compares the Northern Rivers Basin Study (NRBS) area with the other areas of the province. A series of maps and graphs showed the prevalence of certain diseases and disorders within the Peace and Athabasca river basins. The focus of the report was on reproductive health, congenital anomalies, respiratory ailments, circulatory diseases, gastrointestinal disorders, endocrine and metabolic disorders, and neurocognitive disorders. The study showed that compared to other areas of the province, the NRBS area had higher incidences of endometriosis, selected congenital anomalies, bronchitis, pneumonia, peptic ulcers and epilepsy. There were three potential exposure pathways to environmental contaminants. These were through ingestion of water or food, inhalation of air and through dermal exposure. refs., tabs., figs.

  14. Active intra-basin faulting in the Northern Basin of Lake Malawi from seismic reflection data

    Science.gov (United States)

    Shillington, D. J.; Chindandali, P. R. N.; Scholz, C. A.; Ebinger, C. J.; Onyango, E. A.; Peterson, K.; Gaherty, J. B.; Nyblade, A.; Accardo, N. J.; McCartney, T.; Oliva, S. J.; Kamihanda, G.; Ferdinand, R.; Salima, J.; Mruma, A. H.

    2016-12-01

    Many questions remain about the development and evolution of fault systems in weakly extended rifts, including the relative roles of border faults and intra-basin faults, and segmentation at various scales. The northern Lake Malawi (Nyasa) rift in the East African Rift System is an early stage rift exhibiting pronounced tectonic segmentation, which is defined by 100-km-long border faults. The basins also contain a series of intrabasinal faults and associated synrift sediments. The occurrence of the 2009 Karonga Earthquake Sequence on one of these intrabasinal faults indicates that some of them are active. Here we present new multichannel seismic reflection data from the Northern Basin of the Malawi Rift collected in 2015 as a part of the SEGMeNT (Study of Extension and maGmatism in Malawi aNd Tanzania) project. This rift basin is bound on its east side by the west-dipping Livingstone border fault. Over 650 km of seismic reflection profiles were acquired in the Northern Basin using a 500 to 1540 cu in air gun array and a 1200- to 1500-m seismic streamer. Dip lines image a series of north-south oriented west-dipping intra-basin faults and basement reflections up to 5 s twtt near the border fault. Cumulative offsets on intra-basin faults decrease to the west. The largest intra-basin fault has a vertical displacement of >2 s two-way travel time, indicating that it has accommodated significant total extension. Some of these intra-basin faults offset the lake bottom and the youngest sediments by up to 50 s twtt ( 37 m), demonstrating they are still active. The two largest intra-basin faults exhibit the largest offsets of young sediments and also correspond to the area of highest seismicity based on analysis of seismic data from the 89-station SEGMeNT onshore/offshore network (see Peterson et al, this session). Fault patterns in MCS profiles vary along the basin, suggesting a smaller scale of segmentation of faults within the basin; these variations in fault patterns

  15. Atmospheric mercury concentrations in the basin of the amazon, Brazil.

    Science.gov (United States)

    Hachiya, N; Takizawa, Y; Hisamatsu, S; Abe, T; Abe, Y; Motohashi, Y

    1998-01-01

    A wide regional mercury pollution in Amazon, Brazil is closely associated with goldmining that has been carried out in the basin of tributaries of the Amazon since the eighteenth century. Possible involvement has been discussed on atmospheric circulation in distributing the volatile pollutant. We developed a portable air sampler for the collection of mercury compounds and determined atmospheric mercury concentrations at several sites in Brazil including the basin of the Amazon tributaries. The mean concentration of total mercury was between 9.1 and 14.0 ng/m(3) in the basin of the Uatumã River located in the tropical rain forest far from goldmining sites and from urbanized area. These mercury levels exceeded the background level previously reported in rural area and, furthermore, were higher than concentrations observed in Rio de Janeiro and in Manaus that were compatible with the reference values for urban area. Mercury concentrations were also determined in gold refineries in the basin of the Tapajos River, and detected at a significant but not a health deteriorating level. Although only preliminary data were available, the present observations were in favor of the hypothesis that mercury is distributed widely by long distant transport by the atmospheric circulation after released at gold mining sites.

  16. Contribution to the stratigraphy of the onshore Paraiba Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Rossetti, Dilce F.; Valeriano, Marcio M., E-mail: rossetti@dsr.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Divisao de Sensoriamento Remoto; Goes, Ana M.; Brito-Neves, Benjamim B. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. de Geociencias; Bezerra, Francisco H.R.; Ochoa, Felipe L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias Exatas e da Terra. Departamento de Geologia

    2012-06-15

    Several publications have contributed to improve the stratigraphy of the Paraiba Basin in northeastern Brazil. However, the characterization and distribution of sedimentary units in onshore areas of this basin are still incomplete, despite their significance for reconstructing the tectono- sedimentary evolution of the South American passive margin. This work provides new information to differentiate among lithologically similar strata, otherwise entirely unrelated in time. This approach included morphological, sedimentological and stratigraphic descriptions based on surface and sub-surface data integrated with remote sensing, optically stimulated luminescence dating, U+Th/He dating of weathered goethite, and heavy mineral analysis. Based on this study, it was possible to show that Cretaceous units are constrained to the eastern part of the onshore Paraiba Basin. Except for a few outcrops of carbonatic-rocks nearby the modern coastline, deposits of this age are not exposed to the surface in the study area. Instead, the sedimentary cover throughout the basin is constituted by mineralogically and chronologically distinctive deposits, inserted in the Barreiras Formation and mostly in the Post-Barreiras Sediments, of early/middle Miocene and Late Pleistocene-Holocene ages, respectively. The data presented in this work support tectonic deformation as a factor of great relevance to the distribution of the sedimentary units of the Paraiba Basin. (author)

  17. Contribution to the stratigraphy of the onshore Paraiba Basin, Brazil

    International Nuclear Information System (INIS)

    Rossetti, Dilce F.; Valeriano, Marcio M.; Goes, Ana M.; Brito-Neves, Benjamim B.; Bezerra, Francisco H.R.; Ochoa, Felipe L.

    2012-01-01

    Several publications have contributed to improve the stratigraphy of the Paraiba Basin in northeastern Brazil. However, the characterization and distribution of sedimentary units in onshore areas of this basin are still incomplete, despite their significance for reconstructing the tectono- sedimentary evolution of the South American passive margin. This work provides new information to differentiate among lithologically similar strata, otherwise entirely unrelated in time. This approach included morphological, sedimentological and stratigraphic descriptions based on surface and sub-surface data integrated with remote sensing, optically stimulated luminescence dating, U+Th/He dating of weathered goethite, and heavy mineral analysis. Based on this study, it was possible to show that Cretaceous units are constrained to the eastern part of the onshore Paraiba Basin. Except for a few outcrops of carbonatic-rocks nearby the modern coastline, deposits of this age are not exposed to the surface in the study area. Instead, the sedimentary cover throughout the basin is constituted by mineralogically and chronologically distinctive deposits, inserted in the Barreiras Formation and mostly in the Post-Barreiras Sediments, of early/middle Miocene and Late Pleistocene-Holocene ages, respectively. The data presented in this work support tectonic deformation as a factor of great relevance to the distribution of the sedimentary units of the Paraiba Basin. (author)

  18. The Quaternary alluvial systems tract of the Pantanal Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Mario Luis Assine

    Full Text Available ABSTRACT The Pantanal Basin is an active sedimentary basin in central-west Brazil that consists of a complex alluvial systems tract characterized by the interaction between different river systems developed in one of the largest wetlands in the world. The Paraguay River is the trunk river system that drains the water and part of the sediment load received from areas outside of the basin. Depositional styles vary considerably along the river profiles throughout the basin, with the development of entrenched meandering belts, anastomosing reaches, and floodplain ponds. Paleodrainage patterns are preserved on the surface of abandoned lobes of fluvial fans, which also exhibit many degradational channels. Here, we propose a novel classification scheme according to which the geomorphology, hydrological regime and sedimentary dynamics of these fluvial systems are determined by the geology and geomorphology of the source areas. In this way, the following systems are recognized and described: (I the Paraguay trunk-river plains; (II fluvial fans sourced by the tablelands catchment area; (III fluvial fans sourced by lowlands; and (IV fluvial interfans. We highlight the importance of considering the influences of source areas when interpreting contrasting styles of fluvial architectures in the rock record.

  19. Fishes of the Taquari-Antas river basin (Patos Lagoon basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    FG. Becker

    Full Text Available The aquatic habitats of the Taquari-Antas river basin (in the Patos Lagoon basin, southern Brazil are under marked environmental transformation because of river damming for hydropower production. In order to provide an information baseline on the fish fauna of the Taquari-Antas basin, we provide a comprehensive survey of fish species based on primary and secondary data. We found 5,299 valid records of fish species in the basin, representing 119 species and 519 sampling sites. There are 13 non-native species, six of which are native to other Neotropical river basins. About 24% of the total native species are still lacking a taxonomic description at the species level. Three native long-distance migratory species were recorded (Leporinus obtusidens, Prochilodus lineatus, Salminus brasiliensis, as well as two potential mid-distance migrators (Parapimelodus nigribarbis and Pimelodus pintado. Although there is only one officially endangered species in the basin (S. brasiliensis, restricted range species (21.7% of total species should be considered in conservation efforts.

  20. Geothermal resources of the northern gulf of Mexico basin

    Science.gov (United States)

    Jones, P.H.

    1970-01-01

    Published geothermal gradient maps for the northern Gulf of Mexico basin indicate little or no potential for the development of geothermal resources. Results of deep drilling, from 4000 to 7000 meters or more, during the past decade however, define very sharp increases in geothermal gradient which are associated with the occurrence of abnormally high interstitial fluid pressure (geopressure). Bounded by regional growth faults along the landward margin of the Gulf Basin, the geopressured zone extends some 1300 km from the Rio Grande (at the boundary between the United States and Mexico) to the mouth of the Mississippi river. Gulfward, it extends to an unknown distance across the Continental Shelf. Within geopressured deposits, geothermal gradients range upwards to 100 ??C/km, being greatest within and immediately below the depth interval in which the maximum pressure gradient change occurs. The 120 ??C isogeotherm ranges from about 2500 to 5000 m below sea level, and conforms in a general way with depth of occurrence of the top of the geopressured zone. Measured geostatic ratios range upward to 0.97; the maximum observed temperature is 273 ??C, at a depth of 5859 m. Dehydration of montmorillonite, which comprises 60 to 80 percent of clay deposited in the northern Gulf Basin during the Neogene, occurs at depths where temperature exceeds about 80 ??C, and is generally complete at depths where temperature exceeds 120 ??C. This process converts intracrystalline and bound water to free pore water, the volume produced being roughly equivalent to half the volume of montmorillonite so altered. Produced water is fresh, and has low viscosity and density. Sand-bed aquifers of deltaic, longshore, or marine origin form excellent avenues for drainage of geopressured deposits by wells, each of which may yield 10,000 m3 or more of superheated water per day from reservoirs having pressures up to 1000 bars at depths greater than 5000 m. ?? 1971.

  1. The characteristics of ginger-like rock and its geological significance in Northern Zhungeer basin

    International Nuclear Information System (INIS)

    Wu Rengui

    1998-01-01

    The author studies the characteristics of ginger-like stratum and its genesis in northern Zhungeer basin. There are many ginger-like strata of Tertiary-Quaternary exist in northern Zhungeer basin. It shows a good prospect for the formation of Tertiary sandstone type Uranium deposit which can be leached in-situ

  2. Extension of the Parana Basin to offshore Brazil: Implications for coalbed methane evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Holz, M.; Kalkreuth, W.; Rolim, S.B.A. [Universidade Federal do Rio Grande do Sul, Porto Alegre (Brazil)

    2010-05-15

    Coalbed methane (CBM) is a worldwide exploration target of the petroleum industry. In Brazil, the most important coal-bearing succession is associated with the Permian Rio Bonito Formation of the Parana Basin. The gas-prone areas are located at the southeastern margin of the Parana Basin and possibly in the offshore region of the northern part of the Pelotas Basin. Coalfields end abruptly at the present day shoreline, a result of rifting of Gondwana and the evolution of the South Atlantic Ocean. All geologic indicators suggest that in pre-rift times the coal seams extended further eastwards, probably now lying deeply buried below the sedimentary succession of the Pelotas Basin. The present paper discusses structural, stratigraphic, seismic and aeromagenetic data that support the preservation of continental crust beneath ocean sediment. If the coal beds had similar lateral extent to known onshore coals, and coal beds extended across the projected extension of the Parana basin, and there was a conservative 5 m of cumulative coal thickness, then a potential methane volume can be estimated for this newly inferred resource. Average onshore coal gas content is 32 scf/ton (1.00 m(3)/ton). If this is similar in the offshore coal deposits, then the hypothetical methane volume in the offshore area could be in excess of 1.9 x 10(12) scf (56 x 10(9) m(3)). Metamorphism from dikes associated with rifting are potential complicating factors in these deposits, and since no borehole reaching the deep-lying strata in the offshore area are available, this is a hypothetical gas resource with a certain level of uncertainty which should be tested in the future by drilling a deep borehole.

  3. Northern Great Basin Seasonal Lakes: Vulnerability to Climate Change.

    Science.gov (United States)

    Russell, M.; Eitel, J.

    2017-12-01

    Seasonal alkaline lakes in southeast Oregon, northeast California, and northwest Nevada serve as important habitat for migrating birds utilizing the Pacific Flyway, as well as local plant and animal communities. Despite their ecological importance, and anecdotal suggestions that these lakes are becoming less reliable, little is known about the vulnerability of these lakes to climate change. Our research seeks to understand the vulnerability of Northern Great Basin seasonal lakes to climate change. For this, we will be using historical information from the European Space Agency's Global Surface Water Explorer and the University of Idaho's gridMET climate product, to build a model that allows estimating surface water extent and timing based on climate variables. We will then utilize downscaled future climate projections to model surface water extent and timing in the coming decades. In addition, an unmanned aerial system (UAS) will be utilized at a subset of dried basins to obtain precise 3D bathymetry and calculate water volume hypsographs, a critical factor in understanding the likelihood of water persistence and biogeochemical habitat suitability. These results will be incorporated into decision support tools that land managers can utilize in water conservation, wildlife management, and climate mitigation actions. Future research may pair these forecasts with animal movement data to examine fragmentation of migratory corridors and species-specific impacts.

  4. Geochemical evolution of groundwater salinity at basin scale: a case study from Datong basin, Northern China.

    Science.gov (United States)

    Wu, Ya; Wang, Yanxin

    2014-05-01

    A hydrogeochemical investigation using integrated methods of stable isotopes ((18)O, (2)H), (87)Sr/(86)Sr ratios, Cl/Br ratios, chloride-mass balance, mass balance and hydrogeochemical modeling was conducted to interpret the geochemical evolution of groundwater salinity in Datong basin, northern China. The δ(2)H, δ(18)O ratios in precipitation exhibited a local meteoric water line of δ(2)H = 6.4 δ(18)O -5 (R(2) = 0.94), while those in groundwater suggested their meteoric origin in a historically colder climatic regime with a speculated recharge rate of less than 20.5 mm overall per year, in addition to recharge from a component of deep residual ancient lake water enriched with Br. According to the Sr isotope binary mixing model, the mixing of recharges from the Shentou karst springs (24%), the western margins (11%) and the eastern margins (65%) accounts for the groundwater from the deep aquifers of the down-gradient parts in the central basin is a possible mixing mechanism. In Datong, hydrolysis of silicate minerals is the most important hydrogeochemical process responsible for groundwater chemistry, in addition to dissolution of carbonate and evaporites. In the recharge areas, silicate chemical weathering is typically at the bisiallitization stage, while that in the central basin is mostly at the monosiallitization stage with limited evidence of being in equilibrium with gibbsite. Na exchange with bound Ca, Mg prevails at basin scale, and intensifies with groundwater salinity, while Ca, Mg exchange with bound Na locally occurs in the east pluvial and alluvial plains. Although groundwater salinity increases with the progress of water-rock/sediment interactions along the flow path, as a result of carbonate solubility control and continuous evapotranspiration, Na-HCO3 and Na-Cl-SO4 types of water are usually characterized respectively in the deep and the shallow aquifers of an inland basin with a silicate terrain in an arid climatic regime.

  5. Comparison of the rift and post-rift architecture of conjugated salt and salt-free basins offshore Brazil and Angola/Namibia, South Atlantic

    Science.gov (United States)

    Strozyk, Frank; Back, Stefan; Kukla, Peter A.

    2017-10-01

    This study presents a regional comparison between selected 2D seismic transects from large, conjugated salt and salt-free basins offshore southern Brazil (Campos Basin, Santos Basin, Pelotas Basin) and southwest Africa (Kwanza Basin, northern and southern Namibe Basin, Walvis Basin). Tectonic-stratigraphic interpretation of the main rift and post-rift units, free-air gravity data and flexural isostatic backstripping were used for a comprehensive basin-to-basin documentation of key mechanisms controlling the present-day differences in conjugated and neighbouring South Atlantic basins. A significant variation in the tectonic-sedimentary architecture along-strike at each margin and between the conjugated basins across the South Atlantic reflects major differences in (1) the structural configuration of each margin segment at transitional phase between rifting and breakup, as emphasized in the highly asymmetric settings of the large Santos salt basin and the conjugated, salt-free southern Namibe Basin, (2) the post-breakup subsidence and uplift history of the respective margin segment, which caused major differences for example between the Campos and Espirito Santo basins and the conjugated northern Namibe and Kwanza basins, (3) variations in the quantity and distribution of post-breakup margin sediments, which led to major differences in the subsidence history and the related present-day basin architecture, for example in the initially rather symmetric, siliciclastic Pelotas and Walvis basins, and (4) the deposition of Aptian evaporites in the large rift and sag basin provinces north of the Rio Grande Rise and Walvis Ridge, highly contrasting the siliciclastic basins along the margin segments south of the ridges. The resulting present-day architecture of the basins can be generally classified as (i) moderately symmetric, salt-free, and magma-rich in the northern part of the southern segment, (i) highly asymmetric, salt-bearing and magma-poor vs. salt-free and magma

  6. LBA-ECO CD-06 Physical, Political, and Hydrologic Maps, Ji-Parana River Basin, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains physical, hydrologic, political, demographic, and societal maps for the Ji-Parana River Basin, in the state of Rondonia, Brazil. These data...

  7. LBA-ECO CD-06 Physical, Political, and Hydrologic Maps, Ji-Parana River Basin, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains physical, hydrologic, political, demographic, and societal maps for the Ji-Parana River Basin, in the state of Rondonia, Brazil....

  8. Geology of Santa Rita Coal Basin, Rio Grande do Sul, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Correa da Silva, Z.C.; Bortoluzzi, C.A.; Cazzulo-Klepzig, M.; Dias-Fabricio, M.E.; Guerra-Sommer, M.; Marques-Toigo, M.; Paim, P.S.G.; Piccoli, A.E.M.; Silva Filho, B.C.

    1984-04-01

    Data on the sedimentology, stratigraphy, palynology, coal petrography and geochemistry of the Santa Rita Coal Basin, Rio Grande do Sul, Brazil, are presented. The investigations were carried out on samples obtained from drill cores of the sedimentary rocks of Tubarao Supergroup, Lower Permian of Parana Basin. (25 refs.)

  9. Exploration potential of Paraiba and Natal platform basins, NE Brazil; Potencial exploratorio das bacias da Paraiba e da plataforma de Natal, NE do Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Jose A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Lima Filho, Mario; Neumann, Virginio H. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Geologia; Maranhao Neto, Jose Carneiro; Araujo, Joao A.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos Graduacao em Geociencias

    2008-07-01

    The portion of Brazilian continental margin located between the Pernambuco Shear Zone (ZCPE) and Touros High, enclosing Natal Platform and Paraiba basin, NE Brazil, presents a thin sedimentary cover represented by Neo- Cretaceous deposits, over an elevated basement. In this zone the narrow platform ends abruptly against the ocean plate, forming a scarped slope. This area corresponds to the Transverse zone of Northeast Brazil (TZN) limited by two extensive transcurrent E-W shear zones that acted as accommodation zones for the strain produced by the advance of the southern and northern rift branches. During the Aptian, the rift suffered a NE deflection and contoured the Borborema Province and the TZN. The resistance of this block to the rift advance generated a prominent and elevated region into the Atlantic gulf which resulted in the absence of rift deposition over the Brazilian margin and its deviation to the African side. The model suggested by this paper denominates this area as the 'exception zone' of the Brazilian margin, which possess a poor petroliferous potential and need to be separated from the sector corresponding to the Pernambuco basin, located to south of ZCPE, representing the last piece of margin before the rift deflection and possessing an important petroliferous potential. (author)

  10. Petroleum potential of the northern Sinu-San Jacinto Basin, Colombia: an integrated petroleum system and basin modeling approach

    Energy Technology Data Exchange (ETDEWEB)

    Nino, Christian H.; Goncalves, Felix T.T.; Bedregal, Ricardo P. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Modelagem de Bacias (LAB2M); Azevedo, Debora A. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica; Landau, Luis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Metodos Computacionais em Engenharia (LAMCE)

    2004-07-01

    The northern Sinu-San Jacinto basin, located in the northwestern corner of South America (Colombia), belongs to the accretionary prism that resulted from the collision and subduction of the Caribbean plate under the South America plate. Despite all the previous exploratory efforts, solely a few small sub-commercial oil and gas accumulation have been found up to now. The geological and geochemical information acquired by different companies during the lasts decades was integrated with new geochemical analysis and basin modeling to characterize the petroleum systems, to reconstruct the hydrocarbon charge history in the study area and to better assess the exploratory risk. (author)

  11. Records of new localities and hosts for crustacean parasites in fish from the eastern Amazon in northern Brazil.

    Science.gov (United States)

    Oliveira, Marcos Sidney Brito; Corrêa, Lincoln Lima; Oliveira Ferreira, Drielly; Neves, Lígia Rigor; Tavares-Dias, Marcos

    2017-06-01

    The aim of this study was to investigate parasites crustacean fauna in Arapaima gigas , Cichla monoculus , Cichla ocellaris , Cichla jariina , Satanoperca jurupari , Leporinus friderici , Leporinus fasciatus , Hoplias malabaricus , Phractocephalus hemioliopterus , Serrasalmus altispinis , Pseudoplatystoma tigrinum and Potamotrygon motoro of the State Amapá and Pará, in northern Brazil. A total of 242 parasites, including Argulus elongatus , Argulus multicolor, Argulus juparanaensis , Argulus nattereri , Dolops discoidalis , Dolops longicauda , Braga patagonica , Braga fluviatilis , Livoneca guianensis and undetermined Lernaeidae, were collected from these hosts. The Argulus species had the greatest richness among the community of parasitic crustaceans. There was a low abundance of parasites among the hosts, other than D. discoidalis , was most abundant in the integument of A. gigas and P. tigrinum . Finally, the present study reported nine new hosts for the crustacean parasite species and expanded knowledge of the occurrence of some parasite species in the Jari River basin, in eastern Amazon.

  12. Clay mineral facies and lateritization in basalts of the southeastern Parana Basin, Brazil

    International Nuclear Information System (INIS)

    Oliveira, M.T.G. de; Formoso, M.L.L.; Trescases, J.J.; Meunier, A.

    1998-01-01

    Seventeen samples from two lateritic profiles, each with five facies, were studied. These profiles occur on the old planation surface of the plateau basalts of the southern part of ParanáBasin, Brazil. Optical microscopy, X-ray diffraction, electron microprobe, Mössbauer spectroscopy and Fourier Transform Infrared Spectra were used to obtain information about the nature and chemical composition of each weathering facies. In addition, scanning electron microscopy and analyses of clay minerals were performed to detect microcrystalline environmental changes. Both profiles have two major parts: a loose red-clay latosol separated from an underlying mottled clay and an alterite facies; a stone line may or may not be present between the latosol and the underlying units. In both profiles the latosol consists principally of kaolinite, hematite and goethite. Two alterite facies, shaped by differential weathering, are also present in the lower profile: a halloysite–nontronite clayey matrix with a well developed fissure system occurs in the argillaceous alterite and a network of Al–goethite aggregates is typical of the highly porous cortex of the boulder alterite that is found in the stone line and below it. Gibbsite has crystallized in the large pores of porphyritic boulder alterite but is absent in the small pores of the subaphyric boulder alterite. Clay minerals observed in fissures include halloysite associated with goethite and manganese oxides. The basalt has hydrothermal green-clays (mixed layers and trioctahedral smectites) that formed between primary plagioclase, pyroxene and Ti–magnetite crystals while fresh corestones of the boulder alterite have cryptocrystalline iron-rich material. The study of these profiles shows one principal evolutionary trend for clay minerals. This trend is from smectite and mixed layers that form green clays in altered bedrock at the base of the profile to an intermediate association of nontronite and halloysite in the argillaceous

  13. Fishes from the Itapecuru River basin, State of Maranhão, northeast Brazil

    Directory of Open Access Journals (Sweden)

    MC Barros

    Full Text Available The Itapecuru is a relatively large river in the northeastern Brazilian state of Maranhão. During several expeditions to this basin, we collected 69 fish species belonging to 65 genera, 29 families and 10 orders. Characiformes and Siluriformes were the orders with the largest number of species and Characidae, Loricariidae, Cichlidae, Auchenipteridae and Pimelodidae were the richest families. About 30% of the fish fauna of the Itapecuru basin is endemic or restricted to northeastern Brazil. Just over a fifth (22% of the species is also known to occur in the Amazon basin and only a few are more widely distributed in South American.

  14. Uranium prospecting in the Iguatu and Frade basins (Brazil)

    International Nuclear Information System (INIS)

    Lemos, J.C.

    The Mineral Exploration Department of CNEN studied the possibilities of uranium occurences in the Iguatu and Frade Basins in the preliminary research program designated 'Small Basins of the Northeast' which contitutes the object of this report. The two basins are located in the State of Ceara. The results of geologic and radiometric researches ahowed that the possibilities for uranium mineralizations were small, since the analyses of samples from the two main anomalies showed the radioactivity came from the remains of monazite. Further analysis of sedimentologic factors indicated favorable confitions for uranium concentration, taking into consideration the large variations of vertical and lateral granulometries, which permit spectulation about the flow of uraniferous solutions. radiometric measurements of surface samples were insignificant and no uranium mineral was found. The result of research of the sedimentary Frade Basin was negative for uranium mineralization. The basin was entirely eroded, remaining as an outcrop described in this report. (F.E.) [pt

  15. Tectonoestratigraphic and Thermal Models of the Tiburon and Wagner Basins, northern Gulf of California Rift System

    Science.gov (United States)

    Contreras, J.; Ramirez Zerpa, N. A.; Negrete-Aranda, R.

    2014-12-01

    The northern Gulf of California Rift System consist sofa series faults that accommodate both normal and strike-slip motion. The faults formed a series of half-greens filled with more than 7 km of siliciclastic suc­cessions. Here, we present tectonostratigraphic and heat flow models for the Tiburón basin, in the southern part of the system, and the Wag­ner basin in the north. The models are constrained by two-dimensional seis­mic lines and by two deep boreholes drilled by PEMEX­-PEP. Analysis of the seismic lines and models' results show that: (i) subsidence of the basins is controlled by high-angle normal faults and by flow of the lower crust, (ii) basins share a common history, and (iii) there are significant differences in the way brittle strain was partitioned in the basins, a feature frequently observed in rift basins. On one hand, the bounding faults of the Tiburón basin have a nested geometry and became active following a west-to-east sequence of activation. The Tiburon half-graben was formed by two pulses of fault activity. One took place during the protogulf extensional phase in the Miocene and the other during the opening of Gulf of California in the Pleistocene. On the other hand, the Wagner basin is the result of two fault generations. During the late-to middle Miocene, the west-dipping Cerro Prieto and San Felipe faults formed a domino array. Then, during the Pleistocene the Consag and Wagner faults dissected the hanging-wall of the Cerro Prieto fault forming the modern Wagner basin. Thermal modeling of the deep borehole temperatures suggests that the heat flow in these basins in the order of 110 mW/m2 which is in agreement with superficial heat flow measurements in the northern Gulf of California Rift System.

  16. The National Health Services of Brazil and Northern Europe

    DEFF Research Database (Denmark)

    Gurgel Jr., Garibaldi D.; Carvalho de Sousa, Islâandia M.; de Araujo Oliveira, Sydia Rosana

    2017-01-01

    In 1990 the national health services in the United Kingdom and Sweden started to split up in internal markets with purchasers and providers. It was also the year when Brazil started to implement a national health service (SUS) inspired by the British national health service that aimed at principles......, and inequities have increased. The health sector reform in Brazil, on the other hand, contributed to great improvements in population health but never succeeded in changing the fact that more than half of health care spending was private. Demographic and epidemiological changes, with more elderly people having...... chronic disorders and very unequal comorbidities, bring the issue of integrality in the forefront in all 3 countries, and neither the public purchaser provider markets nor the 2-tier system in Brazil delivers on that front. It will demand political leadership and strategic planning with population...

  17. War and early state formation in the northern Titicaca Basin, Peru.

    Science.gov (United States)

    Stanish, Charles; Levine, Abigail

    2011-08-23

    Excavations at the site of Taraco in the northern Titicaca Basin of southern Peru indicate a 2,600-y sequence of human occupation beginning ca. 1100 B.C.E. Previous research has identified several political centers in the region in the latter part of the first millennium B.C.E. The two largest centers were Taraco, located near the northern lake edge, and Pukara, located 50 km to the northwest in the grassland pampas. Our data reveal that a high-status residential section of Taraco was burned in the first century A.D., after which economic activity in the area dramatically declined. Coincident with this massive fire at Taraco, Pukara adopted many of the characteristics of state societies and emerged as an expanding regional polity. We conclude that organized conflict, beginning approximately 500 B.C.E., is a significant factor in the evolution of the archaic state in the northern Titicaca Basin.

  18. Evaluation of water quality at the source of streams of the Sinos River Basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    T Benvenuti

    Full Text Available The Sinos River Basin (SRB is located in the northeastern region of the state of Rio Grande do Sul (29º20' to 30º10'S and 50º15' to 51º20'W, southern Brazil, and covers two geomorphologic provinces: the southern plateau and the central depression. It is part of the Guaíba basin, has an area of approximately 800 km2 and contains 32 counties. The basin provides drinking water for 1.6 million inhabitants in one of the most important industrial centres in Brazil. This study describes different water quality indices (WQI used for the sub-basins of three important streams in the SRB: Pampa, Estância Velha/Portão and Schmidt streams. Physical, chemical and microbiological parameters assessed bimonthly using samples collected at each stream source were used to calculate the Horton Index (HI, the Dinius Index (DI and the water quality index adopted by the US National Sanitation Foundation (NSF WQI in the additive and multiplicative forms. These indices describe mean water quality levels at the streams sources. The results obtained for these 3 indexes showed a worrying scenario in which water quality has already been negatively affected at the sites where three important sub-basins in the Sinos River Basin begin to form.

  19. Paleoproterozoic andesitic volcanism in the southern Amazonian craton (northern Brazil); lithofacies analysis and geodynamic setting

    Science.gov (United States)

    Roverato, Matteo; Juliani, Caetano; Capra, Lucia; Dias Fernandes, Carlos Marcelo

    2016-04-01

    Precambrian volcanism played an important role in geological evolution and formation of new crust. Most of the literature on Precambrian volcanic rocks describes settings belonging to subaqueous volcanic systems. This is likely because subaerial volcanic rocks in Proterozoic and Archean volcano-sedimentary succession are poorly preserved due to erosive/weathering processes. The late Paleoproterozoic Sobreiro Formation (SF) here described, seems to be one of the rare exceptions to the rule and deserves particular attention. SF represents the subaerial expression of an andesitic magmatism that, linked with the upper felsic Santa Rosa F., composes the Uatumã Group. Uatumã Group is an extensive magmatic event located in the Xingú region, southwestern of Pará state, Amazonian Craton (northern Brazil). The Sobreiro volcanism is thought to be related to an ocean-continent convergent margin. It is characterized by ~1880 Ma well-preserved calc-alkaline basaltic/andesitic to andesitic lava flows, pyroclastic rocks and associated reworked successions. The superb preservation of its rock-textures allowed us to describe in detail a large variety of volcaniclastic deposits. We divided them into primary and secondary, depending if they result from a direct volcanic activity (pyroclastic) or reworked processes. Our study reinforces the importance of ancient volcanic arcs and rocks contribution to the terrestrial volcaniclastic sedimentation and evolution of plate tectonics. The volcanic activity that produced pyroclastic rocks influenced the amount of detritus shed into sedimentary basins and played a major role in the control of sedimentary dispersal patterns. This study aims to provide, for the first time, an analysis of the physical volcanic processes for the subaerial SF, based in field observation, lithofacies analysis, thin section petrography and less geochemical data. The modern volcanological approach here used can serve as a model about the evolution of Precambrian

  20. The transgressive-regressive cycle of the Romualdo Formation (Araripe Basin): Sedimentary archive of the Early Cretaceous marine ingression in the interior of Northeast Brazil

    Science.gov (United States)

    Custódio, Michele Andriolli; Quaglio, Fernanda; Warren, Lucas Veríssimo; Simões, Marcello Guimarães; Fürsich, Franz Theodor; Perinotto, José Alexandre J.; Assine, Mario Luis

    2017-08-01

    Geologic events related to the opening of the South Atlantic Ocean deeply influenced the sedimentary record of the Araripe Basin. As consequence, upper stratigraphic units of the basin record a marine ingression in northeastern Brazil during the late Aptian. The timing and stratigraphic architecture of these units are crucial to understand the paleogeography of Gondwana and how the proto-Atlantic Ocean reached interior NE Brazil during the early Cretaceous. This marine ingression is recorded in the Araripe Basin as the Romualdo Formation, characterized by a transgressive-regressive cycle bounded by two regional unconformities. In the eastern part of the basin, the Romualdo depositional sequence comprises coastal alluvial and tide-dominated deposits followed by marine transgressive facies characterized by two fossil-rich intervals: a lower interval of black shales with fossil-rich carbonate concretions (Konservat-Lagerstätten) and an upper level with mollusk-dominated shell beds and shelly limestones. Following the marine ingression, an incomplete regressive succession of marginal-marine facies records the return of continental environments to the basin. The stratigraphic framework based on the correlation of several sections defines a transgressive-regressive cycle with depositional dip towards southeast, decreasing in thickness towards northwest, and with source areas located at the northern side of the basin. The facies-cycle wedge-geometry, together with paleocurrent data, indicates a coastal onlap towards NNW. Therefore, contrary to several paleogeographic scenarios previously proposed, the marine ingression would have reached the western parts of the Araripe Basin from the SSE.

  1. Echovirus 30 associated with cases of aseptic meningitis in state of Pará, Northern Brazil

    Directory of Open Access Journals (Sweden)

    Ceyla Maria Oeiras de Castro

    2009-05-01

    Full Text Available Investigation of the aetiology of viral meningitis in Brazil is most often restricted to cases that occur in the Southern and Southeastern Regions; therefore, the purpose of this study is to describe the viral meningitis cases that occurred in state of Pará, Northern Brazil, from January 2005-December 2006. The detection of enterovirus (EV in cerebrospinal fluid was performed using cell culture techniques, RT-PCR, nested PCR and nucleotide sequencing. The ages of the 91 patients ranged from 60 years old (median age 15.90 years. Fever (87.1%, headache (77.0%, vomiting (61.5% and stiffness (61.5% were the most frequent symptoms. Of 91 samples analyzed, 18 (19.8% were positive for EV. Twelve were detected only by RT- PCR followed by nested PCR, whereas six were found by both cell culture and RT-PCR. From the last group, five were sequenced and classified as echovirus 30 (Echo 30. Phylogenetic analyses revealed that Echo 30 detected in Northern Brazil clustered within a unique group with a bootstrap value of 100% and could constitute a new subgroup (4c according to the phylogenetic tree described by Oberste et al. (1999. This study described the first molecular characterization of Echo 30 in Brazil and this will certainly contribute to future molecular analyses involving strains detected in other regions of Brazil.

  2. Stratigraphic architecture of Devonian lacustrine basins of northern Scotland

    DEFF Research Database (Denmark)

    Kristiansen, Thorben; Moreau, Julien; Andrews, Steven D.

    of this important surface has received relatively little attention. We have utilized vintage onshore seismic to gain a better understanding of the pre-Devonian basement physiography. Onshore exposures of the top Moine, base Devonian unconformity surface is exposed have been visited to ground truth our subsurface...... interpretations. The studied deposits have been deeply buried then exhumed so that they are exposed widely onshore. Post Caledonian tectonism has faulted and folded the Devonian succession making it challenging to reconstruct the stratigraphy and the basin architecture from geological data only. The Devonian...

  3. A seismic hazard overview of the Mitidja Basin (Northern Algeria)

    Science.gov (United States)

    Fontiela, J. F.; Borges, J.; Ouyed, M.; Bezzeghoud, M.; Idres, M.; Caldeira, B.; Boughacha, M. S.; Carvalho, J.; Samai, S.; Aissa, S.; Benfadda, A.; Chimouni, R.; Yalaoui, R.; Dias, R.

    2017-12-01

    The Mitidja Basin (MB) is located in N Algeria and it is filled by quaternary sediments with a length of 100 km on the EW direction and around 20 km width. The S and N limites comprise the Boumerdes-Larbaa-Blida, and the Thenia-Sahel active fault system, respectively. Both fault systems are of the reverse type with opposed dips and accommodate a general slip rate of ˜4 mm/year. In the basin occurred earthquakes that caused severe damage and losses such as the ones of Algiers (1365, Io=X; 1716, Io=X) and the Bourmedes earthquake (Mw 6.9; May 2003) that affected the area of Zemmouri and caused 2.271 deaths. The event was caused by the reactivation of the MB boundary faults. The earthquake generated a max uplift of 0.8m along the coast and a horizontal max. slip of 0.24m.Recent studies show that the Boumerdes earthquake overloaded the adjacent faults system with a stress increase between 0.4 and 1.5 bar. The stress change recommends a detailed study of mentioned faults system due to the increase of the seismic hazard. The high seismogenic potential of the fault system bordering the MB, increases the vulnerability of densely populated areas of Algiers and the amplification effect caused by the basin are the motivation of this project that will focus on the evaluation of the seismic hazard of the region. To achieve seismic hazard assessment on the MB, through realistic predictions of strong ground motion, caused by moderate and large earthquakes, it is important 1) develop a detailed 3D velocity/structure model of the MB that includes geological constraints, seismic reflection data acquired on wells, refraction velocities and seismic noise data, and determination of the attenuation laws based on instrumental records; 2) evaluate the seismic potential and parameters of the main active faults of the MB; 3) develop numerical methods (deterministic and stochastic) to simulate strong ground motions produced by extended seismic sources. To acquire seismic noise were used

  4. Arsenic in terrestrial invertebrates from riparian areas of the Piracicaba River Basin, Sao Paulo State, Brazil

    International Nuclear Information System (INIS)

    Franca, E.J.; Magalhaes, M.R.L.; Santos, M.L.O.; Nadai Fernandes, E.A. de; Fonseca, F.Y.

    2017-01-01

    There is no information on arsenic distribution in terrestrial invertebrates from riparian forests of urban and rural areas in Brazil. The objective of this study was to evaluate the As levels in invertebrates from riverine forests of the Piracicaba River Basin, Sao Paulo, Brazil, using the instrumental neutron activation analysis, k 0 -comparator method. After correction of mass fractions, values higher than 0.10 mg kg -1 were quantified in invertebrates from both urban and agricultural areas. An unexpected As mass fraction of 13 mg kg -1 obtained in the Coleopteran pest Macrodactylus pumilio indicated resistance to As-containing-pesticides. (author)

  5. Sedimentology and chemostratigraphy of a Valanginian carbonate succession from the Baja Guajira Basin, northern Colombia

    Directory of Open Access Journals (Sweden)

    Juan Carlos Silva-Tamayo

    Full Text Available ABSTRACT: The Kesima Member of the Palanz Formation constitutes the first record of Cretaceous marine sedimentation along the Baja Guajira Basin, northern Colombia. Sedimentologic and petrographic analyses suggest a deposition along a coral reef dominated rimmed carbonate platform. 87Sr/86Sr values between 0.707350 and 0.707400 suggest a Valanginian (136 - 132 Ma depositional age for the Kesima Member. A positive anomaly on the δ13C values of ~2.2‰ suggests that this rimmed carbonate platform registered the Valanginian Weissert oceanic anoxic event. Although the Weissert oceanic anoxic event resulted on a major drowning of the Circum Tethyan carbonate platforms, it seems to have not affected those from the Circum Caribbean, where several shallow marine carbonate platform successions crop out. The Kesima Member displays a change from an organically produced carbonate factory into an inorganically produced, ooids dominated, carbonate factory during the peak of the Weissert event δ13C anomaly. This change in the carbonate factory, which may represent a major perturbation of the marine carbonate budget along tropical settings during the Weissert event, coincides with a major decrease in global sea level. Finally, the age of the Kesima Member is considerably older than that of other Cretaceous carbonate successions cropping out in other northern South America sedimentary basins (i.e. Perija-Merida, Cesar-Rancheria. Differences in the timing of the Cretaceous marine incursion along northern South America, together with the differences in the Triassic-Jurassic stratigraphy of several sedimentary basins in northern South America, suggest that the Baja Guajira and Maracaibo basins remained as an isolated tectonic block separated from northern South America after the breakup of Pangea.

  6. Lacustrine basin evolution and coal accumulation of the Middle Jurassic in the Saishiteng coalfield, northern Qaidam Basin, China

    Directory of Open Access Journals (Sweden)

    Meng Li

    2016-07-01

    Full Text Available Based on an extensive borehole survey of the Middle Jurassic coal-bearing sequences in the Saishiteng coalfield, northern Qaidam Basin (NQB, a total of 20 rock types and 5 sedimentary facies were identified, including braided river, meandering river, braided delta, meandering river delta, and lacustrine facies. The distribution of rock types and sedimentary facies contributed to the reconstruction of three periods' sedimentary facies maps of the Middle Jurassic in the Saishiteng coalfield, namely, the Dameigou age, the early Shimengou age and the late Shimengou age. That also provided the basis for the development of a three-stage depositional model of the Middle Jurassic in the NQB, indicating the lacustrine basin of the NQB in the Dameigou age and early Shimengou age were corresponding to an overfill basin, and that in the late Shimengou age was related to a balanced-fill basin. The analysis of the stability and structure of coal seams based on sedimentary facies maps showed that the preferred coal-forming facies in the Saishiteng coalfield were inter-delta bay and interdistributary bay of lower delta plain in the Dameigou age. In particular, the swamps that developed on the subaqueous palaeohigh favored the development of thick coal seams. Thus, minable coal seams may also be found along the Pingtai palaeohigh in the western part of the Saishiteng coalfield.

  7. Neogene palaeogeography and basin evolution of the Western Carpathians, Northern Pannonian domain and adjoining areas

    Science.gov (United States)

    Kováč, Michal; Márton, Emő; Oszczypko, Nestor; Vojtko, Rastislav; Hók, Jozef; Králiková, Silvia; Plašienka, Dušan; Klučiar, Tomáš; Hudáčková, Natália; Oszczypko-Clowes, Marta

    2017-08-01

    The data on the Neogene geodynamics, palaeogeography, and basin evolution of the Western Carpathians, Northern Pannonian domain and adjoining areas (ALCAPA Mega-unit) are summarized, re-evaluated, supplemented, and newly interpreted. The proposed concept is illustrated by a series of palinspastic and palaeotopographic maps. The Miocene development of the Outer Carpathians reflects the vanishing subduction of the residual oceanic and/or thinned continental crust. A compression perpendicular to the front of the orogenic system led to the closing of residual flysch troughs and to accretionary wedge growth, as well as to the development of a foredeep on the margin of the European Platform. Docking of the Outer Western Carpathians accretionary wedge, together with the Central Western Carpathians and Northern Pannonian domain, was accompanied by stretching of the overriding microplate. An orogen parallel and perpendicular extension was associated with the opening and subsidence of the Early and Middle Miocene hinterland (back-arc) basin system that compensated counter-clockwise rotations of the individual crustal fragments of ALCAPA. The Late Miocene development relates to the opening of the Pannonian Basin System. This process was coupled with common stretching of both ALCAPA and Tisza-Dacia Mega-units due to the pull exerted by subduction rollback in front of the Eastern Carpathians. The filling up of the hinterland basin system was associated with thermal subsidence and was followed by the Pliocene tectonic inversion and consequent erosion of the basin system margins, as well as part of the interior.

  8. REGIONAL MAGNETOTELLURIC SURVEYS IN HYDROCARBON EXPLORATION, PARANA BASIN, BRAZIL.

    Science.gov (United States)

    Stanley, William D.; Saad, Antonio; Ohofugi, Walter

    1985-01-01

    The mangetotelluric geophysical method has been used effectively as a hydrocarbon exploration tool in the intracratonic Parana basin of South America. The 1-2 km thick surface basalts and buried diabase sills pose no problem for the magnetotelluric method because the natural electromagnetic fields used as the energy source pass easily through the basalt. Data for the regional study were taken on six profiles with sounding spaced 8 to 15 km apart. The magnetotelluric sounding data outline a linear uplift known as the Ponta Grossa arch. This major structural feature cuts across the northeast-trending intracratonic basin almost perpendicularly, and is injected with numerous diabase dikes. Significant electrical contrasts occur between the Permian sediments and older units, so that magnetotelluric measurements can give an indication of the regional thickness of the Permian and younger sediments to aid in interpreting hydrocarbon migration patterns and possible trap areas. Refs.

  9. Geodynamic implications for zonal and meridional isotopic patterns across the northern Lau and North Fiji Basins

    Science.gov (United States)

    Price, Allison A.; Jackson, Matthew G.; Blichert-Toft, Janne; Kurz, Mark D.; Gill, Jim; Blusztajn, Jerzy; Jenner, Frances; Brens, Raul; Arculus, Richard

    2017-03-01

    We present new Sr-Nd-Pb-Hf-He isotopic data for 65 volcanic samples from the northern Lau and North Fiji Basins. This includes 47 lavas obtained from 40 dredge sites spanning an east-west transect across the Lau and North Fiji basins, 10 ocean island basalt (OIB)-type lavas collected from seven Fijian islands, and eight OIB lavas sampled on Rotuma. For the first time, we are able to map clear north-south and east-west geochemical gradients in 87Sr/86Sr across the northern Lau and North Fiji Basins: lavas with the most geochemically enriched radiogenic isotopic signatures are located in the northeast Lau Basin, while signatures of geochemical enrichment are diminished to the south and west away from the Samoan hot spot. Based on these geochemical patterns and plate reconstructions of the region, these observations are best explained by the addition of Samoa, Rurutu, and Rarotonga hot spot material over the past 4 Ma. We suggest that underplated Samoan material has been advected into the Lau Basin over the past ˜4 Ma. As the slab migrated west (and toward the Samoan plume) via rollback over time, younger and hotter (and therefore less viscous) underplated Samoan plume material was entrained. Thus, entrainment efficiency of underplated plume material was enhanced, and Samoan plume signatures in the Lau Basin became stronger as the trench approached the Samoan hot spot. The addition of subducted volcanoes from the Cook-Austral Volcanic Lineament first from the Rarotonga hot spot, then followed by the Rurutu hot spot, contributes to the extreme geochemical signatures observed in the northeast Lau Basin.

  10. Considerations on fluorides anomalies in Botucatu-Piramboia aquifers system, Parana basin, Brazil

    International Nuclear Information System (INIS)

    Kimmelmann, A.A.; Reboucas, A.C.; Reboucas, A.M.; Heine, C.A.

    1991-01-01

    Groundwater of a great number of deep wells dug to exploit the Botucatu-Piramboia aquifer system in the Parana Basin, Brazil, have high fluoride concentrations, over 1 ppm, that turns groundwater useless for human supply. Investigations being carried out a the Center for Groundwater Research (CEPAS) of the Institute of Geosciences at USP, Sao Paulo, indicate a relationship between fluoride concentration and groundwater age, dated with radiocarbon. (author)

  11. Geochemistry contribution of Pb isotopes on basalts origin study from Parana basin, Brazil

    International Nuclear Information System (INIS)

    Marques, L.S.; Dupre, B.; Allegre, C.J.

    1990-01-01

    This paper presents thirty new Pb-isotope and concentration data for low- and high-tiO sub(2) continental flood basalts of the Parana Basin. The results obtained from representative samples show significant differences with respect to type and location of these basic rocks. The low- and high-TiO sub(2) basalts from the northern region of the Parana Basin exhibit very similar Pb-isotope compositions. On the other hand, the low-TiO sub(2) basalts of central and southern areas, which exhibit low Sr initial isotope ratios (less than 0,7060), show very small variation in Pb isotope compositions which are highly enriched in radiogenic Pb in comparison with the analogues of northern region. The high-TiO sub(2) basic rocks analysed from northern and central regions have the same values for Pb isotope ratios, which are slightly more radiogenic compared with high-TiO sub(2) basalts from southern region. The data obtained, combined with other geochemical (major and trace elements, including rare earths) and isotope (Sr and Nd) results support the view that the basalts from northern and southern areas of the Parana Basin originated in lithospheric mantle reservoirs with different geochemical characteristics. (author)

  12. Prevalence of type-specific HPV among female university students from northern Brazil

    OpenAIRE

    Vieira, Rodrigo Covre; Monteiro, Jeniffer do Socorro Valente; Manso, Est?fane Primo; dos Santos, Maria Renata Mendon?a; Tsutsumi, Mihoko Yamamoto; Ishikawa, Edna Aoba Yassui; Ferrari, Stephen Francis; Lima, Karla Val?ria Batista; de Sousa, Ma?sa Silva

    2015-01-01

    Background Human papillomavirus (HPV) infection is associated with cervical cancer, the most frequent cancer in women from northern Brazil. Assessment of the short-term impact of HPV vaccination depends on the availability of data on the prevalence of type-specific HPV in young women in the pre-immunization period, although these data are currently unavailable for the study region. The aim of this study was to estimate the distribution of all mucosal HPV genotypes, including low- and high-ris...

  13. HYDROLOGICAL REGIME OF GLACIERS IN THE RIVER BASINS OF THE NORTHERN CAUCASUS AND ALTAI

    Directory of Open Access Journals (Sweden)

    V. G. Konovalov

    2018-01-01

    Full Text Available Rivers with snow-glacier alimentation in six basins of the Northern Caucasus (Cherek, Chegem, Baksan, Malka, Teberda, and upper course of the Terek River and Altai (the Katun’ River were investigated in 1946–2005 for the purpose to analyze long-term streamflow variations. It was noted that in 1976–2005 volume of annual runoff increased relative to the previous 30-year interval in four of six rivers of the Northern Caucasus. During the vegetation period the volume of runoff changed synchronously with the annual one. As for the river Katun’, its volumes and variability of both, the annual runoff and that for the vegetation season, decreased. In the course of investigation of spatial-temporal dynamics of hydrological and glaciological characteristics in the above river basins of the Northern Caucasus and the same of Katun’ River the following problems were considered and solved: a the information and methodological basis for regional calculations of the runoff for the rivers with snow-glacier alimentation had been improved and corrected; b changes of the components of hydrological cycle (precipitation, evaporation, and glacier runoff over the glaciation area had been estimated for the period of 1946–2005; c data on quality of the initial glaciological and hydrological information were integrated; d definitions of the runoff were verified by means of comparison of measured runoff with similar values calculated by equation of the annual water budget as a whole for the basin. It should be noted that the total areas of glaciers and areas of their ablation were significantly reduced, but areas and thicknesses of ice under the moraine cover increased. Despite widespread, sometimes twofold decrease in the relative part of glacier alimentation in the total river streamflow for period of April–September this did make almost no effect on the water supply of the vegetation period in individual basins as well as in the whole the Northern

  14. [Food taboos in the northern region of Brazil].

    Science.gov (United States)

    Trigo, M; Roncada, M J; Stewien, G T; Pereira, I M

    1989-12-01

    A study was carried out into alimentary taboos in two localities (São Félix and Murumuru) in the county of Marabá, State of Pará, Brazil. Ninety families were studied in São Félix and thirty-five in Murumuru. As regards the feeding taboos found, the most frequent was that prohibiting the simultaneous ingestion of milk and various types of fruit, including especially mango, orange, cashew and pineapple. The ingestion of eggs with fruit was also considered harmful as well as the eating of mammalian flesh at the same time as fish. Restrictions based on taboos were more frequent during breast feeding than during pregnancy, especially those regarding game flesh and fish that abound in the region under study. The most frequently mentioned reasons for the restrictions were: "the combination causes harm", "the combination kills", "the combination causes congestion" and "it causes vomiting".

  15. Insights on the structural control of a Neogene forearc basin in Northern Chile: A geophysical approach

    Science.gov (United States)

    García-Pérez, Tiaren; Marquardt, Carlos; Yáñez, Gonzalo; Cembrano, José; Gomila, Rodrigo; Santibañez, Isabel; Maringue, José

    2018-06-01

    The comprehensive study of intramountain basins located in the Coastal Cordillera of the continental emergent Andean forearc in Northern Chile, enables the better understanding of the nature and evolution of the upper crustal deformation during the Neogene and Quaternary. A case study is the extensive extensional half-graben Alto Hospicio basin. The basin is cut by the Coastal Cliff, which exposes the deformed Neogene basin fill. Also exposed are several structural systems, some of which affect Quaternary surfaces. The results of the integrated geophysical surveys (Electromagnetic Transient and Gravity) allow us to fully constrain the geometry of the Alto Hospicio basin and the lithological relationship between the subsurface geological units. The structural geology analysis assesses the deformation regimes affecting the faults present in the basin and surrounding area. Altogether evidence a change in the deformation regime from an EW extensional deformation during the Miocene-Pliocene to a NS compression in the Quaternary as is presented in this study. We suggest this deformation change is related to a small change in the convergence vector orientation during the Pliocene.

  16. Flathead River Basin Hydrologic Observatory, Northern Rocky Mountains

    Science.gov (United States)

    Woessner, W. W.; Running, S. W.; Potts, D. F.; Kimball, J. S.; Deluca, T. H.; Fagre, D. B.; Makepeace, S.; Hendrix, M. S.; Lorang, M. S.; Ellis, B. K.; Lafave, J.; Harper, J.

    2004-12-01

    We are proposing the 22, 515 km2 glacially-sculpted Flathead River Basin located in Montana and British Columbia as a Hydrologic Observatory. This hydrologic landscape is diverse and includes large pristine watersheds, rapidly developing intermountain valleys, and a 95 km2 regulated reservoir and 510 km2 lake. The basin has a topographic gradient of over 2,339 m, and spans high alpine to arid climatic zones and a range of biomes. Stream flows are snow-melt dominated and underpinned by groundwater baseflow. The site headwaters contain 37 glaciers and thousands of square kilometers of watersheds in which fire and disease are the only disturbances. In contrast, the HO also contains watersheds at multiple scales that were dominated by glaciers within the last 100 years but are now glacier free, impacted by timber harvests and fires of varying ages to varying degrees, modified by water management practices including irrigation diversion and dams, and altered by development for homes, cities and agriculture. This Observatory provides a sensitive monitor of historic and future climatic shifts, air shed influences and impacts, and the consequences of land and water management practices on the hydrologic system. The HO watersheds are some of the only pristine watersheds left in the contiguous U.S.. They provide critical habitat for key species including the native threaten bull trout and lynx, and the listed western cutthroat trout, bald eagle, gray wolf and the grizzly bear. For the last several thousand years this system has been dominated by snow-melt runoff and moderated by large quantities of water stored in glacial ice. However, the timing and magnitude of droughts and summer flows have changed dramatically. With the information that can be gleaned from sediment cores and landscape records at different scales, this HO provides scientists with opportunities to establish baseline watershed conditions and data on natural hydrologic variability within the system. Such a

  17. New record of the mangrove rivulid Kryptolebias hermaphroditus Costa, 2011 (Cyprinodontiformes: Cynolebiidae) in the Pará state, northern Brazil

    OpenAIRE

    Guimarães-Costa, Auryceia; Schneider, Horacio; Sampaio, Iracilda

    2017-01-01

    The mangrove killifish Kryptolebias herma­phro­ditus is reported to the southeast and northeast regions of Brazil. Recently, a specimen of K. hermaphroditus was collected in a shallow running seawater stream at Ajuruteua beach, Pará state, northern Brazil. This new record is ca. 1,350 km from the nearest previously known occurrence in Rio Grande do Norte state, Brazil. Morphological, molecular, and ecological aspects of this species are described.

  18. Paleozoic unconformities favorable for uranium concentration in northern Appalachian basin

    International Nuclear Information System (INIS)

    Dennison, J.M.

    1986-01-01

    Unconformities can redistribute uranium from protore rock as ground water moves through poorly consolidated strata beneath the erosion surface, or later moves along the unconformity. Groundwater could migrate farther than in present-day lithified Paleozoic strata in the Appalachian basin, now locally deformed by the Taconic and Allegheny orogenies. Several paleoaquifer systems could have developed uranium geochemical cells. Sandstone mineralogy, occurrences of fluvial strata, and reduzate facies are important factors. Other possibilities include silcrete developed during desert exposure, and uranium concentrated in paleokarst. Thirteen unconformities are evaluated to determine favorable areas for uranium concentration. Cambrian Potsdam sandstone (New York) contains arkoses and possible silcretes just above crystalline basement. Unconformities involving beveled sandstones and possible fluvial strata include Cambrian Hardyston sandstone (New Jersey), Cambrian Potsdam Sandstone (New York), Ordovician Oswego and Juniata formations (Pennsylvania and New York), Silurian Medina Group (New York), and Silurian Vernon, High Falls, and Longwood formations (New York and New Jersey). Devonian Catskill Formation is beveled by Pennsylvanian strata (New York and Pennsylvania). The pre-Pennsylvanian unconformity also bevels Lower Mississippian Pocono, Knapp, and Waverly strata (Pennsylvania, New York, and Ohio), truncates Upper Mississippian Mauch Chunk Formation (Pennsylvania), and forms paleokarst on Mississippian Loyalhanna Limestone (Pennsylvania) and Maxville Limestone (Ohio). Strata associated with these unconformities contain several reports of uranium. Unconformities unfavorable for uranium concentration occur beneath the Middle Ordovician (New York), Middle Devonian (Ohio and New York), and Upper Devonian (Ohio and New York); these involve marine strata overlying marine strata and probably much submarine erosion

  19. The Paleozoic ichthyofauna of the Amazonas and Parnaíba basins, Brazil

    Science.gov (United States)

    Figueroa, Rodrigo Tinoco; Machado, Deusana Maria da Costa

    2018-03-01

    The Brazilian Paleozoic ichthyofauna from the Parnaíba and Amazonas basins regard a sparsely known diversity, including chondrichthyans and acanthodians, besides some osteichthyan remains. This work proposes a revision of the fossil material from these two sedimentary basins and synthesizes the morphological aspect of such material trying to understand the influences of those fossils to the paleontology of the region, comparing the Brazilian fossils with other gondwanan faunas. The Brazilian Paleozoic fish fauna shows great resemblance to those of Bolivia, especially during the Devonian. Many of the Acanthodian spines from the Manacapuru Formation (Amazonas Basin), and the Pimenteira Formation (Parnaíba Basin), are comparable to the taxa found in Bolivia. The lack of more Placoderm remains in the Brazilian outcrops is similar to the low diversity of this group in Bolivia, when compared to other South American and Euramerican localities. The most diverse Brazilian ichthyofauna is encountered in the Permian Pedra de Fogo Formation where numerous chondrichthyans and 'paleopterygians' remains are found, together with dipnoans and actinistians. Despite the apparent lack of more representative Paleozoic ichthyofaunas in Brazil, the available material that ranges from Lower Devonian to early Permian from Brazil bears important taxa that could address valuable taxonomic and biogeographic informations.

  20. The Frasnian-Famennian boundary (Upper Devonian) in black shale sequences: US Southern Midcontinent, Illinois Basin, and northern Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Over, D.J. (State Univ. of New York, Geneseo, NY (United States). Dept. of Geological Sciences)

    1994-04-01

    The Frasnian-Famennian (F/F) boundary in the Woodford Shale of the US southern Midcontinent, Sweetland Creek Shale of the Illinois Basin, and the Hanover Shale of the northern Appalachian Basin is recognized to a discrete horizon. In each locality the boundary is marked by evidence of a disconformity: phosphate nodules, concentration of conodonts, or coated and corroded grains. The Woodford Shale consists of finely laminated pyritic organic-rich shale containing interbeds of greenish shale and chert. The F/F boundary horizon is marked by a concentration of conodonts and phosphatic nodules. The boundary lag horizon contains Pa. linguliformis, Pa. subperlobtata, Pa. delicatula delicatula, and Pa. triangularis. Underlying laminations contain Ancyrognathus ubiquitus and Pa. triangularis indicating that the disconformity is within the uppermost MN Zone 13 or Lower triangularis Zone. The upper portion of the Type Sweetland Creek Shale consists of dark organic-rich shales. The F/F boundary is located within an interval containing three green shale interbeds. Palmatolepis triangularis in the absence of Frasnian species first occurs in the middle green shale. In the thick Upper Devonian clastic sequence of the northern Appalachian Basin the F/F boundary is within an interval of interbedded pyritic green and organic-rich silty shales of the Hanover Shale. At Irish Gulf strata containing Pa. triangularis overlie finely laminated dark shales containing Pa. bogartensis, Pa. triangularis, Pa. winchell, Ancyrodella curvata, and Icriodus alternatus. The conodont fauna transition is below a conodont-rich laminae containing a Famennian fauna that marks the boundary horizon.

  1. Northern Rivers Basins ecological and human health studies : summary, relevance and recommendations

    International Nuclear Information System (INIS)

    1999-04-01

    Residents in northern Alberta expressed concerns that the original Northern River Basins Study (NRBS) only examined the impacts of contaminants on ecological health and did not include impacts on human health. In response to these concerns, Alberta Health established the Northern River Basins Human Health Monitoring Program in 1994 to investigate the possible relationships between various environmental risk factors and the health of northern residents in the province. This document links the ecological information collected by the original NRBS program with the information provided by the health program. Issues regarding health impacts from pulp mills and oil sand mining were also discussed. The findings of the health program were summarized and recommendations were made for future studies. The contaminants of potential concern (COPC) arising from the original NRBS were described in terms of their sources and any known connections between exposure and human health. The COPCs included arsenic, dioxins, chlorinated furans, polycyclic aromatic hydrocarbons (PAH) polychlorinated biphenyls (PCB) mercury, chlorinated phenolics, toxaphene, carbon monoxide, nitrogen oxides, ozone, sulphur dioxide, acid sulphates and particulate matter. Examples of Canadian regulatory criteria for these contaminants were also presented. 41 refs., 1 tab

  2. Status and understanding of groundwater quality in the Northern Coast Ranges study unit, 2009: California GAMA Priority Basin Project

    Science.gov (United States)

    Mathany, Timothy M.; Belitz, Kenneth

    2015-01-01

    Groundwater quality in the 633-square-mile (1,639-square-kilometer) Northern Coast Ranges (NOCO) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program and the U.S. Geological Survey (USGS) National Water-Quality Assessment Program. The study unit is composed of two study areas (Interior Basins and Coastal Basins) and is located in northern California in Napa, Sonoma, Lake, Colusa, Mendocino, Glenn, Humboldt, and Del Norte Counties. The GAMA-PBP is being conducted by the California State Water Resources Control Board in collaboration with the USGS and the Lawrence Livermore National Laboratory.

  3. Silviculture of eucaliptus plantations in the Paraiba do Sul basin, Brazil, and its potential implication on the basin ecohydrology.

    Science.gov (United States)

    Carriello, Felix; Andres Rodriguez, Daniel; Marques Neves, Otto; Vicens, Raul

    2014-05-01

    Silviculture of eucaliptus plantations is an important driver of the Mata Atlântica biome conversion into another land use in the Paraíba do Sul basin, in the southeastern of Brazil. This region is located in one of the most developed areas in Brazil, between Rio de Janeiro and São Paulo, the most important cities in Brazil, linked by Presidente Dutra highway. Between both cities there are another cities that produce a variety of goods - from meat to planes, cars and mobile phones. This area is, at the same time, one the most important hot spot for the Mata Atlântica biome. Here we have a large Mata Atlântica fragment protected by law and others fragments being conversed to pasture, agriculture, silviculture and urban areas. Paraiba do Sul river drains the region and runs into Rio de Janeiro State. The basin is highly anthropized, with multiple approaches of its waters resources. Its waters also serve Rio de Janeiro metropolitan area. Because land use and land cover changes impact the water yield in a basin, the study of its dynamic its of great importance for water resources management. We study the land use and land cover change in the region between 1986 and 2010, focusing in the development of silviculture of eucaliptus plantations. We used the HAND (Height Above Nearest Drainage) approach that uses the height above the nearest water body, acquired from SRTM Data and transformed into a Terrain Numeric Mode, to classify the landscape into three different ecohydrological environments: floodplain, mountain top and hillslope. This classes were intersected with 1986 and 2010 land use and cover change classification obtained from Landsat imagery. Results show that silviculture has increased in the region from 1986 to 2010. In both years, silviculture areas are mainly located at the hillslope (47%), while floodplain and mountain top share 28 % and 23 % respectively. Available census data from the Brazilian Institute of Geography and Statistics, IBGE, for 1995 and

  4. Coastal rocky reef fishes of Santa Catarina's northern islands, Brazil

    Directory of Open Access Journals (Sweden)

    Johnatas Adelir Alves

    2015-11-01

    Full Text Available The coast of the state of Santa Catarina only has non-biogenic reefs, i.e. rocky and artificial reefs, and is considered the geographic south limit for many reef fish species. At present the diversity of organisms associated with reef environments is threatened. This study aimed to record the number of families and species of reef fish fauna of the north coast of the state of Santa Catarina. The data were collected through underwater visual census performed on Graças archipelago (26°12'S /48º29'W, Tamboretes archipelago (26°22'S/48°31'W and Barra do Sul islands (26°27'S/48º35'W. A total of 166 species was observed (6 elasmobranchii and 160 actinopterygii belonging to 66 families. The families with more species richness were Carangidae (16, Epinephelidae (9, Blenidae (8, Serranidae (7, Haemulidae (6, Sparidae (6 Tetraodontidae (6, Labridae-Scarini (5, Labrisomidae (5 Pomacentridae (5, Lutjanidae (5 and Muraenidae (5. This study add to the current published list, new 115 species, including new occurrences (e.g. Chromis limbata, and some endemic (e.g. Sparisoma amplum, exotic (e.g. Omobranchus punctatus, endangered (e.g. Hippocampus erectus and overexploited (e.g. Lutjanus analis species. Twenty one species are present in the IUCN’s list, twelve in the IBAMA’s list and four in the local list. All elasmobranchii recorded here are considered threatened species, like the brazilian guitarfish (Rhinobatos horkelii, which appears in three red lists, and it is considered critically endangered. All species of Epinephelidae are mentioned in the list of risk categories of the IUCN and five are cited as overexploited or threatened with overexploitation by IBAMA. Among Epinephelidae, the goliath grouper (Epinephelus itajara, is present in all red lists and has specific protection rules in Brazil. The gathered information will allow to take appropriate conservation measures, such as the establishment of marine protected areas, monitoring of fishing

  5. Water environments: anthropogenic pressures and ecosystem changes in the Atlantic drainage basins of Brazil.

    Science.gov (United States)

    Marques, Marcia; da Costa, Monica F; Mayorga, Maria Irles de O; Pinheiro, Patrícia R

    2004-02-01

    Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.

  6. THE BRAZILIAN BIODIESEL PROGRAM AND REGIONAL DEVELOPMENT: CASES FROM NORTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Alves Finco

    2011-12-01

    Full Text Available Biofuel production has been greatly discussed in Brazil. In 2004, these debates led the country to develop new policies and implement a national program for biodiesel use and production (PNPB with the intent to increase the share of renewable energy and foster regional development. In this context, the present study aims to assess the impacts of PNPB on regional development in Tocantins State, northern Brazil. For this purpose, ranges of socio-economic indicators were collected among national and regional stakeholders, as well as specific literature. The preliminary results point out that distribution logistics appears to be a considerable constraint to the success of the PNPB. The concentration of biodiesel industries in the central-west region of the country, and the large distances to deliver biodiesel in the northern Brazil make biodiesel prices non-competitive when compared to fossil diesel. The results also suggest that the PNPB is not succeeding in promoting the integration of family agriculture in the Tocantins state, especially due to the structural difficulty of the agricultural sector, as well as the technical and political shortcomings presented by the mechanism of incentives.

  7. Prospect analysis for sandstone-type uranium mineralization in the northern margin of Qaidam basin

    International Nuclear Information System (INIS)

    Liu Lin; Song Xiansheng; Feng Wei; Song Zhe; Li Wei

    2010-01-01

    Affected by the regional geological structural evolution, a set of sedimentary structure, i.e. the construction of coal-bearing classic rocks which is in favor of the sandstone-type uranium mineralization has deposited in the northern margin of Qaidam Basin since Meso-Cenozoic. A NWW thrust nappe tectonic belt, i.e. the ancient tectonic belt which is the basis for the development of ancient interlayer oxidation zone formed by the tectonic reverse in late Jurassic and Cretaceous. The Mid and late Jurassic layer was buried by the weak extension in Paleogene and the depression in early Neogene. The extrusion reversal from late Neogene to Quaternary made the basin into the development era of the modern interlayer oxidation zone. It can be concluded that the layer of the northern margin of Qaidam Basin has the premise for the formation of sandstone-type uranium ore. Based on the analysis of the characteristics of the thrust belt, the structure of the purpose layer, the sand body, the hydrogeology, the interlayer oxidation zone and uranium mineralization, the results indicated that the ancient interlayer oxidation zone is the prospecting type of sandstone-type uranium ore. Beidatan and the east of Yuqia are the favorable prospective area of sandstone-type uranium mineralization. (authors)

  8. Hydrogeochemistry of high-fluoride groundwater at Yuncheng Basin, northern China

    International Nuclear Information System (INIS)

    Li, Chengcheng; Gao, Xubo; Wang, Yanxin

    2015-01-01

    Hydrogeochemical and environmental isotope methods were integrated to delineate the spatial distribution and enrichment of fluoride in groundwater at Yuncheng Basin in northern China. One hundred groundwater samples and 10 Quaternary sediment samples were collected from the Basin. Over 69% of the shallow groundwater (with a F − concentration of up to 14.1 mg/L), 44% of groundwater samples from the intermediate and 31% from the deep aquifers had F − concentrations above the WHO provisional drinking water guideline of 1.5 mg/L. Groundwater with high F − concentrations displayed a distinctive major ion chemistry: Na-rich and Ca-poor with a high pH value and high HCO 3 − content. Hydrochemical diagrams and profiles and hydrogen and oxygen isotope compositions indicate that variations in the major ion chemistry and pH are controlled by mineral dissolution, cation exchange and evaporation in the aquifer systems, which are important for F − mobilization as well. Leakage of shallow groundwater and/or evaporite (gypsum and mirabilite) dissolution may be the major sources for F − in groundwater of the intermediate and deep aquifers. - Highlights: • High-F − groundwater widely occurs in Yuncheng Basin of northern China. • High-F − groundwater is Na and HCO 3 -rich and Ca-poor, with high pH. • Major hydrogeochemical processes are mineral dissolution, ion exchange and evaporation. • Shallow groundwater leakage/evaporite dissolution may cause F enrichment in lower aquifers

  9. Study of southern CHAONAN sag lower continental slope basin deposition character in Northern South China Sea

    Science.gov (United States)

    Tang, Y.

    2009-12-01

    Northern South China Sea Margin locates in Eurasian plate,Indian-Australia plate,Pacific Plates.The South China Sea had underwent a complicated tectonic evolution in Cenozoic.During rifting,the continental shelf and slope forms a series of Cenozoic sedimentary basins,including Qiongdongnan basin,Pearl River Mouth basin,Taixinan basin.These basins fill in thick Cenozoic fluviolacustrine facies,transitional facies,marine facies,abyssal facies sediment,recording the evolution history of South China Sea Margin rifting and ocean basin extending.The studies of tectonics and deposition of depression in the Southern Chaonan Sag of lower continental slope in the Norther South China Sea were dealt with,based on the sequence stratigraphy and depositional facies interpretation of seismic profiles acquired by cruises of“China and Germany Joint Study on Marine Geosciences in the South China Sea”and“The formation,evolution and key issues of important resources in China marginal sea",and combining with ODP 1148 cole and LW33-1-1 well.The free-air gravity anomaly of the break up of the continental and ocean appears comparatively low negative anomaly traps which extended in EW,it is the reflection of passive margin gravitational effect.Bouguer gravity anomaly is comparatively low which is gradient zone extended NE-SW.Magnetic anomaly lies in Magnetic Quiet Zone at the Northern Continental Margin of the South China Sea.The Cenozoic sediments of lower continental slope in Southern Chaonan Sag can be divided into five stratum interface:SB5.5,SB10.5,SB16.5,SB23.8 and Hg,their ages are of Pliocene-Quaternary,late Miocene,middle Miocene,early Miocene,paleogene.The tectonic evolution of low continental slope depressions can be divided into rifting,rifting-depression transitional and depression stages,while their depositional environments change from river to shallow marine and abyssa1,which results in different topography in different stages.The topographic evolvement in the study

  10. Systematic heat flow measurements across the Wagner Basin, northern Gulf of California

    Science.gov (United States)

    Neumann, Florian; Negrete-Aranda, Raquel; Harris, Robert N.; Contreras, Juan; Sclater, John G.; González-Fernández, Antonio

    2017-12-01

    A primary control on the geodynamics of rifting is the thermal regime. To better understand the geodynamics of rifting in the northern Gulf of California we systematically measured heat-flow across the Wagner Basin, a tectonically active basin that lies near the southern terminus of the Cerro Prieto fault. The heat flow profile is 40 km long, has a nominal measurement spacing of ∼1 km, and is collocated with a seismic reflection profile. Heat flow measurements were made with a 6.5-m violin-bow probe. Although heat flow data were collected in shallow water, where there are significant temporal variations in bottom water temperature, we use CTD data collected over many years to correct our measurements to yield accurate values of heat flow. After correction for bottom water temperature, the mean and standard deviation of heat flow across the western, central, and eastern parts of the basin are 220 ± 60, 99 ± 14, 889 ± 419 mW m-2, respectively. Corrections for sedimentation would increase measured heat flow across the central part of basin by 40 to 60%. We interpret the relatively high heat flow and large variability on the western and eastern flanks in terms of upward fluid flow at depth below the seafloor, whereas the lower and more consistent values across the central part of the basin are suggestive of conductive heat transfer. Moreover, heat flow across the central basin is consistent with gabbroic underplating at a depth of 15 km and suggests that continental rupture here has not gone to completion.

  11. Giant kidney worm (Dioctophyma renale) infections in dogs from Northern Paraná, Brazil.

    Science.gov (United States)

    Nakagawa, Tizianne Larissa Duim Ribeiro; Bracarense, Ana Paula Frederico Rodrigues Loureiro; dos Reis, Antônio Carlos Faria; Yamamura, Milton Hissashi; Headley, Selwyn Arlington

    2007-04-30

    This article describes the pathological observations of Dioctophyma renale in dogs from the northern region of the State of Paraná, Brazil. A female, 6-year-old dog, Fila Brasileiro breed and a 16-year-old, male Poodle were diagnosed positive for D. renale during routine necropsy. Clinically, both dogs demonstrated hematuria, and the Poodle had a radiographic diagnosis of prostatic tumor, but neither had a clinical diagnosis of this infection prior to necropsy. Three giant worms were observed in the urinary bladder of the first case and one within the renal pelvis of the other dog. Histological findings were similar in both cases and represented compressive atrophy due to the presence of the nematode. Additionally, aspects of the life cycle, pathogenesis and epidemiology associated with this parasitism in Brazil are also discussed.

  12. Northern tamarisk beetle (Diorhabda carinulata) and tamarisk (Tamarix spp.) interactions in the Colorado River basin

    Science.gov (United States)

    Nagler, Pamela L.; Nguyen, Uyen; Bateman, Heather L.; Jarchow, Christopher; Glenn, Edward P.; Waugh, William J.; van Riper, Charles

    2018-01-01

    Northern tamarisk beetles (Diorhabda carinulata) were released in the Upper Colorado River Basin in the United States in 2004–2007 to defoliate introduced tamarisk shrubs (Tamarix spp.) in the region’s riparian zones. The primary purpose was to control the invasive shrub and reduce evapotranspiration (ET) by tamarisk in an attempt to increase stream flows. We evaluated beetle–tamarisk interactions with MODIS and Landsat imagery on 13 river systems, with vegetation indices used as indicators of the extent of defoliation and ET. Beetles are widespread and exhibit a pattern of colonize–defoliate–emigrate, so that riparian zones contain a mosaic of completely defoliated, partially defoliated, and refoliated tamarisk stands. Based on satellite data and ET algorithms, mean ET before beetle release (2000–2006) was 416 mm/year compared to postrelease (2007–2015) ET of 355 mm/year (pprojections that ET would be reduced by 300–460 mm/year. Reasons for the lower-than-expected ET reductions are because baseline ET rates are lower than initially projected, and percentage ET reduction is low because tamarisk stands tend to regrow new leaves after defoliation and other plants help maintain canopy cover. Overall reductions in tamarisk green foliage during the study are 21%. However, ET in the Upper Basin has shown a steady decline since 2007 and equilibrium has not yet been reached. Defoliation is now proceeding from the Upper Basin into the Lower Basin at a rate of 40 km/year, much faster than initially projected.

  13. Paleozoic evolution of active margin basins in the southern Central Andes (northwestern Argentina and northern Chile)

    Science.gov (United States)

    Bahlburg, H.; Breitkreuz, C.

    The geodynamic evolution of the Paleozoic continental margin of Gondwana in the region of the southern Central Andes is characterized by the westward progression of orogenic basin formation through time. The Ordovician basin in the northwest Argentinian Cordillera Oriental and Puna originated as an Early Ordovician back-arc basin. The contemporaneous magmatic arc of an east-dipping subduction zone was presumably located in northern Chile. In the back-arc basin, a ca. 3500 meter, fining-up volcaniclastic apron connected to the arc formed during the Arenigian. Increased subsidence in the late Arenigian allowed for the accomodation of large volumes of volcaniclastic turbidites during the Middle Ordovician. Subsidence and sedimentation were caused by the onset of collision between the para-autochthonous Arequipa Massif Terrane (AMT) and the South American margin at the Arenigian-Llanvirnian transition. This led to eastward thrusting of the arc complex over its back-arc basin and, consequently, to its transformation into a marine foreland basin. As a result of thrusting in the west, a flexural bulge formed in the east, leading to uplift and emergence of the Cordillera Oriental shelf during the Guandacol Event at the Arenigian-Llanvirnian transition. The basin fill was folded during the terminal collision of the AMT during the Oclóyic Orogeny (Ashgillian). The folded strata were intruded post-tectonically by the presumably Silurian granitoids of the "Faja Eruptiva de la Puna Oriental." The orogeny led to the formation of the positive area of the Arco Puneño. West of the Arco Puneño, a further marine basin developed during the Early Devonian, the eastern shelf of which occupied the area of the Cordillera Occidental, Depresión Preandina, and Precordillera. The corresponding deep marine turbidite basin was located in the region of the Cordillera de la Costa. Deposition continued until the basin fill was folded in the early Late Carboniferous Toco Orogeny. The basin

  14. Pollen grains in quaternary sediments from the Campos Basin, state of Rio de Janeiro, Brazil: Core BU-91-GL-05

    Directory of Open Access Journals (Sweden)

    Aline Gonçalves de Freitas

    2013-12-01

    Full Text Available Here, we describe pollen grains extracted from a Pleistocene-Holocene sediment core (BU-91-GL-05; 22°48'45"S; 41°54'13"W taken from the Albacora Slope (22°48'45"S; 41°54'13"W, located in the Campos Basin of the northern region of the state of Rio de Janeiro, Brazil. The analysis resulted in the identification and morphological description of 46 types of pollen: one of a gymnosperm genus (Podocarpus; and 45 of angiosperm taxa across 27 families-one family of monocotyledons (Poaceae and 26 families (30 types of dicotyledons. The most common angiosperm families were Amaranthaceae (Chenopodium, Amaranthus and Gomphrena; Fabaceae (Fabaceae type, Bauhinia, Inga and Canavalia; Malpighiaceae (Tetrapteris, Heteropteris and Peixotoa; Malvaceae (Sida, Abutilon, Hibiscus and Pseudobombax; Rubiaceae (Faramea, Borreria and Psychotria; Asteraceae (Eupatorium and tribe Vernonieae; Bignoniaceae (Bignoniaceae type, Adenocalymma and Tabebuia; and Onagraceae (Fuchsia and Ludwigia. The palynoflora in this study are associated with dense montane and submontane Atlantic Forest, semideciduous forest and restinga (coastal woodland, all of which are present in the state of Rio de Janeiro. Palynological analysis can provide important data about paleovegetation and paleoclimatic changes in the studied area during the Quaternary, specifically in the last 145,000 years.

  15. A new species of the Hypostomus cochliodongroup (Siluriformes: Loricariidae from the rio Aripuanã basin in Brazil

    Directory of Open Access Journals (Sweden)

    Cláudio H. Zawadzki

    Full Text Available A new species of Hypostomus, H. dardanelos, is described from the rio Aripuanã basin, a southern tributary to the rio Madeira, in northern Mato Grosso State, Brazil. The new species is assigned to the Hypostomus cochliodon group by the possession of few teeth, spoon-shaped teeth, angle between dentaries usually less than 80°, and by the absence of a notch between hyomandibular and the metapterygoid. The new species can be diagnosed from its congeners by its unique color pattern of yellowish-brown ground color covered by well-defined dark spots of relatively equal size, evenly spaced and moderately set along the dorsal region of the body and fins, except on the ventrolateral region of the caudal peduncle and proximal region of anal and caudal fins, which are devoid of spots. The new species is further diagnosed by having teeth with very small lateral cusp, fused to the mesial one and almost imperceptible; by the absence of medial buccal papillae, and by nuptial odontodes all along the body (odontodes more pronounced in some few larger specimens.

  16. A new species of Ituglanis (Siluriformes: Trichomycteridae from the rio Uruguai basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    Juliano Ferrer

    2017-10-01

    Full Text Available ABSTRACT A new species of Ituglanis associated to the grasslands of the Pampa biome is described from the rio Uruguai basin, southern Brazil. The new species is distinguished from its congeners by the low number of ribs and by a unique color pattern composed of an outer layer with scattered round black blotches equivalent in size to the eye circumference over a reddish brown background on the lateral surface of the body. We provide the genetic sequences of the mitochondrial gene Cytochrome c Oxydase subunit I (COI for three of the paratypes and discuss aspects about the recent discovery of the new species.

  17. Geochemical characterization and miospore biochronostratigraphy of the Frasnian anoxic event in the Parnaiba basin, Northeast Brazil

    International Nuclear Information System (INIS)

    Rodrigues, R.; De Melo, J.H.G.; Alves, D.B.; Loboziak, S.

    1995-01-01

    Radioactive shales of Frasnian age in the Parnaiba Basin present high concentrations of organic matter. They correspond to a condensed section related to the Devonian maximum marine transgression. Combined geochemical, palynological and clay mineral data point out to a dominant algal contribution in the composition of the organic matter, as well as to anoxic depositional settings. This radioactive shale interval corresponds to the onset of a long-lasting, global anoxic event which was to be intensified in the Late Frasnian, and thus can be regarded as a marker for chronostratigraphic correlations. It includes the main source rocks of Devonian age in the Palaeozoic basins of north Brazil, and therefore represents a target of potential interest for hydrocarbon exploration. (authors). 16 refs., 10 figs., 1 tab., 17 photos

  18. Geochemical characterization and miospore biochronostratigraphy of the Frasnian anoxic event in the Parnaiba basin, Northeast Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, R.; De Melo, J.H.G.; Alves, D.B. [Universidade Federal, Rio de Janeiro, RJ (Brazil); Loboziak, S. [Lille-1 Univ., 59 - Villeneuve-d`Ascq (France)

    1995-12-31

    Radioactive shales of Frasnian age in the Parnaiba Basin present high concentrations of organic matter. They correspond to a condensed section related to the Devonian maximum marine transgression. Combined geochemical, palynological and clay mineral data point out to a dominant algal contribution in the composition of the organic matter, as well as to anoxic depositional settings. This radioactive shale interval corresponds to the onset of a long-lasting, global anoxic event which was to be intensified in the Late Frasnian, and thus can be regarded as a marker for chronostratigraphic correlations. It includes the main source rocks of Devonian age in the Palaeozoic basins of north Brazil, and therefore represents a target of potential interest for hydrocarbon exploration. (authors). 16 refs., 10 figs., 1 tab., 17 photos.

  19. Cretaceous-Paleogene ostracods from the Paraíba Basin, northeastern Brazil

    Science.gov (United States)

    de Lima Barros, Cecília; Piovesan, Enelise Katia; Oliveira Agostinho, Sonia Maria

    2018-04-01

    This work presents a detailed taxonomic study on the marine ostracods from the Paraíba Basin, northeastern Brazil, in wells from the wells Itamaracá-1IT-03-PE and Poty-1PO-01-PE, which record the Maastrichtian-Danian boundary. Besides the taxonomic data, this paper contributes to the paleoenvironmental knowledge of Cretaceous-Paleogene ostracods from the Paraíba Basin. The analysis of 98 samples of the well Itamaracá-1IT-03-PE and 59 samples of the Poty-1PO-01-PE resulted in the record of 34 ostracode species, all representative of a marine environment with normal salinity. Seven new species are proposed: Cytherella centrocompressa sp. nov.; Cytherella paraibensis sp. nov.; Neonesidea potyensis sp. nov.; Bythoceratina spinosa sp. nov.; Eucytherura ventrotuberculata sp. nov.; Langiella fauthi sp. nov. and Protobuntonia punctatum sp. nov.

  20. Holocene faulting in the Bellingham forearc basin: upper-plate deformation at the northern end of the Cascadia subduction zone

    Science.gov (United States)

    Kelsey, Harvey M.; Sherrod, Brian L.; Blakely, Richard J.; Haugerud, Ralph A.

    2013-01-01

    The northern Cascadia forearc takes up most of the strain transmitted northward via the Oregon Coast block from the northward-migrating Sierra Nevada block. The north-south contractional strain in the forearc manifests in upper-plate faults active during the Holocene, the northern-most components of which are faults within the Bellingham Basin. The Bellingham Basin is the northern of four basins of the actively deforming northern Cascadia forearc. A set of Holocene faults, Drayton Harbor, Birch Bay, and Sandy Point faults, occur within the Bellingham Basin and can be traced from onshore to offshore using a combination of aeromagnetic lineaments, paleoseismic investigations and scarps identified using LiDAR imagery. With the recognition of such Holocene faults, the northernmost margin of the actively deforming Cascadia forearc extends 60 km north of the previously recognized limit of Holocene forearc deformation. Although to date no Holocene faults are recognized at the northern boundary of the Bellingham Basin, which is 15 km north of the international border, there is no compelling tectonic reason to expect that Holocene faults are limited to south of the international border.

  1. Parotocinclus seridoensis, a new hypoptopomatine catfish (Siluriformes: Loricariidae from the upper rio Piranhas-Açu basin, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Telton Pedro A. Ramos

    Full Text Available A new species of Parotocinclus is described from the upper rio Piranhas-Açu basin, northeastern Brazil. The new species differs from all its congeners, except P. bidentatus, P. muriaensis (both from rio Paraíba do Sul basin, southeastern Brazil, and P. spilurus (rio Jaguaribe basin, northeastern Brazil by presenting the adipose fin rudimentary or absent. The new species differs from P. bidentatus, P. muriaensis, and P. spilurus mainly by presenting the abdomen region extensively naked, with few reduced rounded dermal platelets between the pectoral girdle and the anus. Parotocinclus seridoensis is probably an endemic species of the semi-arid Caatinga, region where the genus presents high species richness.

  2. Temporal evaluation of soil use conflicts in the Formoso river basin, state of Tocantins, Brazil

    Directory of Open Access Journals (Sweden)

    Kaio Cesar Cardoso de Lima Fonseca Alves

    2015-09-01

    Full Text Available The importance of permanent preservation areas (PPA is mainly associated to their environmental role to maintain, preserve, and conserve water resources and ecosystems within a basin. The objective of this study was to delimitate and quantify the areas of PPA along watercourses as well as anthropized areas within PPAs boundaries, in the Formoso river basin, state of Tocantins, Brazil. PPAs area was delimited considering boundaries according to the Brazilian Forest Law. We sampled areas within the watercourses classified up to hierarchical Level 4. Watercourses handling draw, automatic delimitation of PPA, and visual classification of the soil use conflicts based on LANDSAT 5 TM of 1985, 1998 and 2011 were carried out on Geographical Information System ArcGIS. PPA of the watercourses sampled in this study represent 1.14% (24,491.35 ha of the drainage area of the Formoso river basin. For 1985, an area of about 3,616.48 ha was quantified, which is characterized by conflicts related to soil use. However, these conflict areas were reduced to 3,341.25 ha and 3,345.37 ha, respectively, for 1998 and 2011. Due to the intense agricultural land expansion observed in the basin in the last decades, the mentioned reductions in soil use conflicts between 1985 and 1998 and subsequent maintenance can be linked to changes on Brazilian environmental legislation.

  3. Taxonomic revision of the fossil pulmonate mollusks of Itaboraí Basin (Paleocene, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Brincalepe Salvador

    2013-01-01

    Full Text Available The limestones of Itaboraí Basin (Middle Paleocene, Rio de Janeiro, Brazil, harbor a rich fossil molluscan fauna consisting exclusively of pulmonate snails, both terrestrial and freshwater. An extensive taxonomic revision of this paleofauna is conducted here. A new genus, Cortana, is described as well as two new species, Eoborus fusiforme and Gastrocopta itaboraiensis. The revised classification is as follows: Austrodiscus lopesi (Charopidae; Biomphalaria itaboraiensis (Planorbidae; "Brachypodella" britoi (Urocoptidae; Brasilennea arethusae, Brasilennea guttula, Brasilennea minor (Cerionidae; Bulimulus fazendicus, Bulimulus trindadeae, Cortana carvalhoi, Cyclodontina coelhoi, Itaborahia lamegoi, Leiostracus ferreirai, Plagiodontes aff. dentatus (Orthalicidae; Cecilioides sommeri (Ferussaciidae; Eoborus rotundus, Eoborus sanctijosephi, Eoborus fusiforme (Strophocheilidae; Gastrocopta mezzalirai, Gastrocopta itaboraiensis (Gastrocoptidae; Temesa magalhaesi (Clausiliidae. The species Strobilopsis mauryae was considered a synonym of Brasilennea arethusae; Bulimulus sommeri a synonym of Itaborahia lamegoi; and Vorticifex fluminensis a synonym of Eoborus sanctijosephi. Itaboraí Basin has the most ancient records of the families Orthalicidae, Gastrocoptidae, Ferussaciidae and Strophocheilidae. Moreover, the basin's records of Charopidae, Clausiliidae, Cerionidae, and Urocoptidae are among the most ancient in the world and, among these, those of Cerionidae, Clausiliidae and Urocoptidae deserve special attention since they are greatly removed from these families' current distribution. Additionally, Itaboraí has the most ancient records for the genera Austrodiscus, Brachypodella, Bulimulus, Cecilioides, Cyclodontina, Eoborus, Gastrocopta, Leiostracus, Plagiodontes and Temesa. There are three endemic genera in the basin: Brasilennea, Cortana and Itaborahia. Further discussion on paleobiogeography and evolution of this paleofauna is also provided.

  4. Geology, Streamflow, and Water Chemistry of the Talufofo Stream Basin, Saipan, Northern Mariana Islands

    Science.gov (United States)

    Izuka, Scot K.; Ewart, Charles J.

    1995-01-01

    A study of the geology, streamflow, and water chemistry of Talufofo Stream Basin, Saipan, Commonwealth of the Northern Mariana Islands, was undertaken to determine the flow characteristics of Talufofo Stream and the relation to the geology of the drainage basin. The Commonwealth government is exploring the feasibility of using water from Talufofo Stream to supplement Saipan's stressed municipal water supply. Streamflow records from gaging stations on the principal forks of Talufofo Stream indicate that peak streamflows and long-term average flow are higher at the South Fork gaging station than at the Middle Fork gaging station because the drainage area of the South Fork gaging station is larger, but persistent base flow from ground-water discharge during dry weather is greater in the Middle Fork gaging station. The sum of the average flows at the Middle Fork and South Fork gaging stations, plus an estimate of the average flow at a point in the lower reaches of the North Fork, is about 2.96 cubic feet per second or 1.91 million gallons per day. Although this average represents the theoretical maximum long-term draft rate possible from the Talufofo Stream Basin if an adequate reservoir can be built, the actual amount of surface water available will be less because of evaporation, leaks, induced infiltration, and reservoir-design constraints. Base-flow characteristics, such as stream seepage and spring discharge, are related to geology of the basin. Base flow in the Talufofo Stream Basin originates as discharge from springs near the base of limestones located in the headwaters of Talufofo Stream, flows over low-permeability volcanic rocks in the middle reaches, and seeps back into the high-permeability limestones in the lower reaches. Water sampled from Talufofo Stream during base flow had high dissolved-calcium concentrations (between 35 and 98 milligrams per liter), characteristic of water from a limestone aquifer. Concentrations of potassium, sodium, and chloride

  5. A new species of Scinax Wagler, 1830 (Anura: Hylidae from the middle Amazon river basin, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo José Sturaro

    2014-01-01

    Full Text Available A new species of the hylid genus Scinax is described and illustrated. The new taxon was found in the Amazonian rainforest of northern Brazil, municipalities of Maués and Careiro da Várzea, state of Amazonas. The new species is characterized by its moderate size (male mean snout-vent length 36.3mm; body robust; large, orange, black-bordered axillary and inguinal spots; and bilobate vocal sac. This new species was found in primary and secondary forest on branches of shrubs or trees in, or next to, permanent ponds and flooded areas.

  6. Amazon river basin evapotranspiration and its influence on the rainfall in southern Brazil

    Science.gov (United States)

    Folegatti, M. V.; Wolff, W.

    2017-12-01

    Amazon river basin (ARB) presents a positive water balance, i.e. the precipitation is higher than evapotranspiration. Regarding the regional circulation, ARB evapotranspiration represents an important source of humidity for the South of Brazil. Thus, the aim of this work is to answer the question: how much is the correlation between ARB evapotranspiration and rainfall in South of Brazil? The shapefiles data of ARB and countries/states boundary were obtained through the Oak Ridge National Laboratory (ORNL) and Instituto Brasileiro de Geografia e Estatística (IBGE), respectively. According to rasters data, the precipitation was obtained from study of Numerical Terradynamic Simulation Group (NTSG) for images of Moderate Resolution Imaging Spectroradiometer (MODIS), under code MOD16A2, whereas rasters data for evapotranspiration were obtained from National Aeronautics and Space Administration (NASA) by Tropical Rainfall Measuring Mission Multi-Satellite Precipitation Analysis (TMPA), under code 3B43_V7. The products MOD16A2 and 3B43_V7 have a respective spatial resolution of 0.5º and 0.25º, and a monthly temporal resolution from January/2000 to December/2014. For ARB and South region of Brazil was calculated the mean evapotranspiration and mean precipitation through the pixels within of the respective polygons. To answer the question of this work was performed the cross-correlation analysis between these time series. We observed the highest value for the lag that corresponds the begin of spring (October), being 0.3 approximately. As a result, the mean precipitation on South region of Brazil during spring and summer was in the order of 15% to 30 %, explained by ARB evapotranspiration. For this reason, the maintenance of ARB is extremely important for water resource grant in South of Brazil.

  7. Detection of the pandemic norovirus variant GII.4 Sydney 2012 in Rio Branco, state of Acre, northern Brazil

    Directory of Open Access Journals (Sweden)

    Luciana Damascena da Silva

    2013-12-01

    Full Text Available Noroviruses (NoVs are important cause of gastroenteritis in humans worldwide. Genotype GII.4 is responsible for the majority of outbreaks reported to date. This study describes, for the first time in Brazil, the circulation of NoV GII.4 variant Sydney 2012 in faecal samples collected from children aged less than or equal to eight years in Rio Branco, state of Acre, northern Brazil, during July-September 2012.

  8. Hydrology of the Upper Capibaribe Basin, Pernambuco, Brazil - A reconnaissance in an Area of Crystalline Rocks

    Science.gov (United States)

    Chada Filho, Luiz Goncalves; Dias Pessoa, Mario; Sinclair, William C.

    1966-01-01

    The upper Capibaribe basin is the western three-fourths, approximately, of the valley of the river that empties into the Atlantic Ocean at Recife, the capital of the State of Pernambuco, Brazil. It is the part of the drainage basin that is within the Drought Polygon of northeast Brazil, and it totals about 5,400 square kilometers. It receives relatively abundant precipitation in terms of the annual average, yet is regarded as hot subhumid to semiarid because the precipitation is uneven from year to year and place to place. The dependable water supply, therefore, is small. The basin has water, which could be put to better use than at present, but the opportunities for augmenting the usable supply are not great. The streams are intermittent and therefore cannot be expected to fill surface reservoirs and to keep them filled. The ground-water reservoirs have small capacity--quickly filled and quickly drained. A rough estimate based on the records for 1964 suggests that, of 4,700 million cubic meters of precipitation in the upper Capibaribe basin, 2,700 million cubic meters (57 percent) left the basin as runoff and 2,000 million cubic meters {43 percent) went into underground storage or was evaporated or transpired. The bedrock of the upper Capibaribe basin is composed of granite, gneiss, schist, and other varieties of crystalline rocks, which have only insignificant primary permeability. They are permeable mainly where fractured. The principal fracture zones, fortunately, are in the valleys, where water accumulates and can feed into them, but the volume of fractured rock is small in relation to the basin as a whole. A well in a large water-filled fracture zone may yield up to 20,000 liters per hour, but the average well yields less than one-fourth this amount, and some wells yield none. The saprolite, or weathered rock, is many meters thick at some places especially in the eastern half of the upper Capibaribe basin. It contains water locally, but ordinarily will yield

  9. The flora of Early Permian coal measures from the Parana Basin in Brazil: A review

    International Nuclear Information System (INIS)

    Iannuzzi, Roberto

    2010-01-01

    This paper presents an updated overview integrating both previous and newly published data on the most important floras found associated with Early Permian coal seams in the Parana Basin, Brazil. These floras occur within the Rio Bonito Formation and correspond to the Gondwana ''Glossopteris Flora.'' For this review, five floras are selected, in ascending stratigraphic order: the ''Sao Joao do Triunfo,'' ''Figueira,'' ''Quiteria,'' ''Morro do Papaleo'' and ''Irapua Bed'' floras. They are the best-known floras of the basin in terms of taxonomic composition, paleoecology and environments of deposition. An early-mid Sakmarian to earliest Artinskian age is indicated for the Rio Bonito Formation based on absolute radiometric and relative biostratigraphic ages. Integration of available information about the selected floras allows evaluation of taphonomic and paleoecological factors to provide a more comprehensive understanding of the Early Permian floral record in the Parana Basin. The variation observed in both the taxonomic composition of individual floras and in the frequency of occurrence of different plant groups is due to the broad range of environmental/edaphic conditions that prevailed in the many different depositional settings represented in the Rio Bonito Formation. A more precise age determination obtained for the plant-bearing deposits permits the establishment of a more confident correlation between the Early Permian floral succession in the Parana Basin and other Early Permian floral successions in other basins. The Sakmarian global warming favored the appearance of pecopterid and sphenopterid ferns amongst the spore-producing plants, and the glossopterids amongst the pollen-producing plants. (author)

  10. Forming mechanism of the Ordovician karst carbonate reservoirs on the northern slope of central Tarim Basin

    Directory of Open Access Journals (Sweden)

    Heng Fu

    2017-07-01

    Full Text Available The Ordovician karst carbonate reservoirs on the northern slope of central Tarim Basin are important oil and gas exploration targets in the basin, but their dissolution mechanisms are in controversy. In this paper, based on the integrated study of sedimentation, sequence and reservoir, together with microscopic analysis and macroscopic seismic data analysis, the carbonate karst reservoirs in the study area were divided into three types: dissolved pore-cavity limestone reservoir, pore-cavity dolomite reservoir and fracture-cavity siliceous reservoir, and their forming mechanisms were discussed respectively. Some findings were obtained. First, dissolved pore-cavity limestone reservoirs are distributed in the upper Yingshan Fm and Yijianfang Fm of the Ordovician vertically, while pore-cavity dolomite reservoirs are mainly developed in the Penglai Fm and lower Yingshan Fm of the Ordovician with great thickness. Second, dissolved pore-cavity limestone reservoirs were formed by karstification on the third-order sequence boundary (lowstand tract, while pore-cavity dolomite reservoirs were formed by deep burial dolomitization controlled by karstification on the third-order sequence boundary, both of which are distributed in the highstand tract below the third-order sequence boundary. Third, siliceous reservoirs are developed under the control of faulting, as a result of reworking of deep hydrothermal fluids along faults to the limestone, and the siliceous reservoirs and their hydrothermal solution fracture-cavity systems are distributed near faults. It is further predicted that, in addition to the three types of reservoir above, platform-margin reef-flat reservoirs are developed in the Ordovician on the northern slope of central Tarim Basin.

  11. Decreased runoff response to precipitation, Little Missouri River Basin, northern Great Plains, USA

    Science.gov (United States)

    Griffin, Eleanor R.; Friedman, Jonathan M.

    2017-01-01

    High variability in precipitation and streamflow in the semiarid northern Great Plains causes large uncertainty in water availability. This uncertainty is compounded by potential effects of future climate change. We examined historical variability in annual and growing season precipitation, temperature, and streamflow within the Little Missouri River Basin and identified differences in the runoff response to precipitation for the period 1976-2012 compared to 1939-1975 (n = 37 years in both cases). Computed mean values for the second half of the record showed little change (precipitation, but average annual runoff at the basin outlet decreased by 22%, with 66% of the reduction in flow occurring during the growing season. Our results show a statistically significant (p runoff response to precipitation (runoff ratio). Surface-water withdrawals for various uses appear to account for 1°C increases in January through March, are the dominant driver of the observed decrease in runoff response to precipitation in the Little Missouri River Basin.

  12. Diversity of non-biting midge larvae assemblages in the Jacuí River basin, Brazil.

    Science.gov (United States)

    Floss, Elzira Cecília Serafini; Kotzian, Carla Bender; Spies, Márcia Regina; Secretti, Elisangela

    2012-01-01

    The richness and composition of a mountain-river chironomid larvae assemblage in the Jacuí River basin, Brazil were studied, and compared with other riverine non-biting midge larvae assemblages previously studied in the country. Additionally, the influence of some regional-scale environmental characteristics on the spatial distribution of these assemblages was tested. The specimens were collected at 12 sites in the middle course of the Jacuí River basin (in the state of Rio Grande do Sul) between April 2000 and May 2002. Around 100 taxa were recorded. The dominant taxa belonged to the genera Rheotanytarsus, Cricotopus, Polypedilum, and Pseudochironomus. Twenty-two rare taxa were found, representing 22% of the total of taxa inventoried. Fourteen genera (Aedokritus, Axarus, Endotribelos, Kiefferulus, Manoa, Oukuriella, Phaenopsectra, Stenochironomus, Xenochironomus, Xestochironomus, Cardiocladius, Metriocnemus, Paracladius, and Rheocricotopus) represent new occurrences in Rio Grande do Sul. The similarity analysis of the chironomid larvae assemblages inventoried in 32 regions of Brazil indicated five groups with similarity higher than 50%. The groups, when the effects of spatial autocorrelation were removed, displayed a weak positive correlation between the assemblage composition and the aquatic system or hydraulic conditions and the hydrographic basin, and a weak negative correlation in relation to the biome. The altitude showed no correlation with the composition of the assemblage. The relatively high richness of the region surveyed in relation to other Brazilian regions corroborates some tendencies already noted in other parts of the world, such as: i) lotic systems may constitute an exception to the rule that diversity is greater in tropical regions, ii) regions of transitional relief may contain the greatest richness of Chironomidae, and iii) in rivers, the group might have its spatial distribution influenced to a greater extent by local environmental

  13. Fish, Corumbataí and Jacaré-Pepira river basins, São Paulo State, Brazil

    OpenAIRE

    Gomiero, Leandro; Braga, Francisco

    2006-01-01

    Fish were studied in two river basins (Corumbataí and Jacaré-Pepira) subjected to strong human pressure, in the interior of the State of São Paulo, southeastern Brazil. In the Corumbataí basin, four sites were sampled: Cabeça river, Lapa stream, Passa-Cinco river, and Corumbataí river; in the Jacaré-Pepira basin, three sites were sampled: Tamanduá stream, Jacaré-Pepira river, and Água Branca stream. A total of 4,050 specimens belonging to 48 species and 13 families were caught and analyzed....

  14. Fish, Corumbataí and Jacaré-Pepira river basins, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Braga, F. M. S.

    2006-01-01

    Full Text Available Fish were studied in two river basins (Corumbataí and Jacaré-Pepira subjected to strong human pressure, in the interior of the State of São Paulo, southeastern Brazil. In the Corumbataí basin, four sites were sampled: Cabeça river, Lapa stream, Passa-Cinco river, and Corumbataí river; in the Jacaré-Pepira basin, three sites were sampled: Tamanduá stream, Jacaré-Pepira river, and Água Branca stream. A total of 4,050 specimens belonging to 48 species and 13 families were caught and analyzed.

  15. MECHANISMS CONTROLLING SURFACE WATER QUALITY IN THE COBRAS RIVER SUB-BASIN, NORTHEASTERN BRAZIL

    Directory of Open Access Journals (Sweden)

    ALEXANDRE DE OLIVEIRA LIMA

    2017-01-01

    Full Text Available Stream water quality is dependent on many factors, including the source and quantity of the streamflow and the types of geology and soil along the path of the stream. This study aims to evaluate the origin and the mechanisms controlling the input of ions that effect surface water quality in the sub-basin of the Rio das Cobras, Rio Grande do Norte state, Northeastern Brazil. Thirteen ponds were identified for study: three in the main river and ten in the tributaries between, thus covering the whole area and lithology of the sub-basin. The samples were collected at two different times (late dry and rainy periods in the hydrological years 2009 and 2010, equating to total of four collection times. We analyzed the spatial and seasonal behavior of water quality in the sub-basin, using Piper diagrams, and analyzed the source of the ions using Guibbs diagram and molar ratios. With respect to ions, we found that water predominate in 82% sodium and 76% bicarbonate water (cations and anions, respectively. The main salinity control mechanism was related to the interaction of the colloidal particles (minerals and organic sediment with the ions dissolved in water. Based on the analysis of nitrates and nitrites there was no evidence of contamination from anthropogenic sources.

  16. Assessment of Mercury Concentration in Turtles (Podocnemis unifilis in the Xingu River Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Marina Teófilo Pignati

    2018-06-01

    Full Text Available Many studies on mercury contamination in aquatic biota deal with the effect of consuming metal-contaminated organisms on human health. In this study, we examined the factors that cause mercury contamination in Podocnemis unifilis in the Xingu River Basin of Mato Grosso and Pará States, Brazil. We quantified by atomic absorption spectroscopy with cold vapor the total mercury (THg content in the liver and muscle samples of 50 Podocnemis unifilis specimens collected from the basin. The liver and muscle samples contained 134.20 ± 119.30 ng g−1 THg and 24.86 ± 26.36 ng g−1 THg, respectively. Each chelonian or meal has, on average, 5.34× more Hg than the highest level established as acceptable. From the results it can be inferred that, given the weekly consumption of chelonians, the riverine and indigenous communities in the Xingu River Basin are at risk of chronic consumption of Hg in amounts beyond the acceptable limit. The potential high risk to the health of this population is evident; however, the risk classification needs to be further studied.

  17. Detrital fission-track-compositional signature of an orogenic chain-hinterland basin system: The case of the late Neogene Quaternary Valdelsa basin (Northern Apennines, Italy)

    Science.gov (United States)

    Balestrieri, M. L.; Benvenuti, M.; Tangocci, F.

    2013-05-01

    Detrital thermochronological data collected in syn-tectonic basin deposits are a promising tool for deciphering time and processes of the evolution of orogenic belts. Our study deals with the Valdelsa basin, one of the wider basins of central Tuscany, Italy. The Valdelsa basin is located at the rear of the Northern Apennines, a collisional orogen whose late Neogene Quaternary development is alternatively attributed to extensional and compressional regimes. These contrasting interpretations mostly rely on different reconstructions of the tectono-sedimentary evolution of several basins formed at the rear of the chain since the late Tortonian. Here, we explore the detrital thermochronological-compositional signature of tectonic and surface processes during the Valdelsa basin development. For this aim, detrital apatite fission-track analysis of 21 sand samples from the latest Messinian Gelasian fluvial to shallow marine basin deposits, has been accompanied by a clast composition analysis of 7 representative outcrops of the conglomerate facies. The grain-age distributions of the sediment samples are generally characterized by two distinct components, one younger peak (P1) varying between 5.5 ± 2.8 and 9.5 ± 1.0 Ma and one older peak (P2) varying from 15.0 ± 8.0 to 41.0 ± 10 Ma. By comparison with some bedrock ages obtained from the E-NE basin shoulder, we attributed the P2 peak to the Ligurian Units and the P1 peak to the Macigno Formation (Tuscan Units). These units are arranged one upon the other in the complex nappe pile forming the Northern Apennines orogen. While the gravel composition indicates a predominant feeding from the Ligurian units all along the sedimentary succession with a subordinate occurrence of Macigno pebbles slightly increasing upsection, the P1 peak is present even in the oldest collected sandy sediments. The early P1 occurrence reveals that the Macigno was exposed in the E-NE basin shoulder since at least the latest Messinian-early Zanclean

  18. [Poles of American tegumentary leishmaniasis production in northern Paraná State, Brazil].

    Science.gov (United States)

    Monteiro, Wuelton Marcelo; Neitzke, Herintha Coeto; Silveira, Thaís Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana; Teodoro, Ueslei; Ferreira, Maria Eugênia Moreira Costa

    2009-05-01

    American tegumentary leishmaniasis is endemic in the State of Paraná, with 99.3% of the cases reported in the South of Brazil. Spatial distribution of the disease in northern Paraná was verified, identifying the most relevant geographic areas in epidemiological terms. The study used data recorded on epidemiological forms from the Teaching and Research Clinical Test Laboratory of the State University in Maringá, from 1987 to 2004. The study only included individuals that were infected in the municipalities (counties) in northern Paraná. Identification of the epidemiological units (poles and circuits) was based on spatial density of cases, according to the model proposed by the National Health Foundation, considering the most likely infection sites. Considering 1,933 reported cases, 1,611 were infected in northern Paraná. American tegumentary leishmaniasis distribution in Paraná State suggests two circuits for production of the disease: Paraná-Paranapanema, highlighting the Cinzas-Laranjinha, Tibagi, Ivaí-Pirapó, Piquiri, and Baixo Iguaçu poles, and Ribeira, highlighting the Alto Ribeira pole.

  19. Northern tamarisk beetle (Diorhabda carinulata) and tamarisk (Tamarix spp.) interactions in the Colorado River basin

    Science.gov (United States)

    Nagler, Pamela L.; Nguyen, Uyen; Bateman, Heather L.; Jarchow, Christopher; Glenn, Edward P.; Waugh, William J.; van Riper, Charles

    2018-01-01

    Northern tamarisk beetles (Diorhabda carinulata) were released in the Upper Colorado River Basin in the United States in 2004–2007 to defoliate introduced tamarisk shrubs (Tamarix spp.) in the region’s riparian zones. The primary purpose was to control the invasive shrub and reduce evapotranspiration (ET) by tamarisk in an attempt to increase stream flows. We evaluated beetle–tamarisk interactions with MODIS and Landsat imagery on 13 river systems, with vegetation indices used as indicators of the extent of defoliation and ET. Beetles are widespread and exhibit a pattern of colonize–defoliate–emigrate, so that riparian zones contain a mosaic of completely defoliated, partially defoliated, and refoliated tamarisk stands. Based on satellite data and ET algorithms, mean ET before beetle release (2000–2006) was 416 mm/year compared to postrelease (2007–2015) ET of 355 mm/year (p<0.05) for a net reduction of 61 mm/year. This is lower than initial literature projections that ET would be reduced by 300–460 mm/year. Reasons for the lower-than-expected ET reductions are because baseline ET rates are lower than initially projected, and percentage ET reduction is low because tamarisk stands tend to regrow new leaves after defoliation and other plants help maintain canopy cover. Overall reductions in tamarisk green foliage during the study are 21%. However, ET in the Upper Basin has shown a steady decline since 2007 and equilibrium has not yet been reached. Defoliation is now proceeding from the Upper Basin into the Lower Basin at a rate of 40 km/year, much faster than initially projected.

  20. Adaptation to changing water resources in the Ganges basin, northern India

    International Nuclear Information System (INIS)

    Moors, Eddy J.; Groot, Annemarie; Biemans, Hester; Terwisscha van Scheltinga, Catharien; Siderius, Christian; Stoffel, Markus; Huggel, Christian; Wiltshire, Andy; Mathison, Camilla; Ridley, Jeff; Jacob, Daniela; Kumar, Pankaj

    2011-01-01

    An ensemble of regional climate model (RCM) runs from the EU HighNoon project are used to project future air temperatures and precipitation on a 25 km grid for the Ganges basin in northern India, with a view to assessing impact of climate change on water resources and determining what multi-sector adaptation measures and policies might be adopted at different spatial scales. The RCM results suggest an increase in mean annual temperature, averaged over the Ganges basin, in the range 1-4 o C over the period from 2000 to 2050, using the SRES A1B forcing scenario. Projections of precipitation indicate that natural variability dominates the climate change signal and there is considerable uncertainty concerning change in regional annual mean precipitation by 2050. The RCMs do suggest an increase in annual mean precipitation in this region to 2050, but lack significant trend. Glaciers in headwater tributary basins of the Ganges appear to be continuing to decline but it is not clear whether meltwater runoff continues to increase. The predicted changes in precipitation and temperature will probably not lead to significant increase in water availability to 2050, but the timing of runoff from snowmelt will likely occur earlier in spring and summer. Water availability is subject to decadal variability, with much uncertainty in the contribution from climate change. Although global social-economic scenarios show trends to urbanization, locally these trends are less evident and in some districts rural population is increasing. Falling groundwater levels in the Ganges plain may prevent expansion of irrigated areas for food supply. Changes in socio-economic development in combination with projected changes in timing of runoff outside the monsoon period will make difficult choices for water managers. Because of the uncertainty in future water availability trends, decreasing vulnerability by augmenting resilience is the preferred way to adapt to climate change. Adaptive policies are

  1. Integrative assessment of sediment quality in lower basin affected by former mining in Brazil.

    Science.gov (United States)

    Bonnail, Estefanía; Buruaem, Lucas M; Morais, Lucas G; Araujo, Giuliana S; Abessa, Denis M S; Sarmiento, Aguasanta M; Ángel DelValls, T

    2017-06-13

    The Ribeira de Iguape River (Southeast Brazil) is metal contaminated by mining activities. Despite it has been cataloged as "in via of restoration" by the literature, this basin is still a sink of pollution in some segments of the fluvial system. This study aimed to assess the sediment quality in the lower part of the RIR basin. The employed approach was based on biological responses of the freshwater clam Corbicula fluminea after 7-day exposure bioassays using as the reference site the Perequê Ecological Park. Toxic responses (burial activity and lethality) and biochemical biomarkers (GST, GR, GPx, LPO, MTs, AChE and DNA damage) were evaluated and then integrated with metal bioavailability and chemical concentrations to address the sediment quality in the area through the weight-of-evidence approach. A multivariate analysis identified linkages between biological responses and contamination. Results pointed that, despite being below the benchmarks of the US Environmental Protection Agency, there is slight metal contamination in the lower part of the basin which induces oxidative stress in C. fluminea; other toxic responses were sometimes attributed to As and Cr bioaccumulation. The sediment quality values (TEL-PEL values in mg/kg) were calculated for the current study for As (0.63-1.31), Cr (3.5-11.05), Cs (1.0-1.17), Cu (6.32-7.32), Ni (6.78-7.46), Ti (42.0-215), V (1.77-8.00). By comparison with other international guidelines, the sediment quality of the lower basin of the Vale de Ribeira does not identify a significant environmental risk.

  2. Estimation of Phosphorus Emissions in the Upper Iguazu Basin (brazil) Using GIS and the More Model

    Science.gov (United States)

    Acosta Porras, E. A.; Kishi, R. T.; Fuchs, S.; Hilgert, S.

    2016-06-01

    Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions) model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations) and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for about 56% of the

  3. ESTIMATION OF PHOSPHORUS EMISSIONS IN THE UPPER IGUAZU BASIN (BRAZIL USING GIS AND THE MORE MODEL

    Directory of Open Access Journals (Sweden)

    E. A. Acosta Porras

    2016-06-01

    Full Text Available Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for

  4. A Miocene wave-dominated estuarine system in the Paraíba Basin, northeastern Brazil

    Science.gov (United States)

    Gandini, Rosana; Rossetti, Dilce de Fátima; Netto, Renata Guimarães; Góes, Ana Maria

    2017-11-01

    A number of publications have documented the effect of the Miocene transgression on several coasts of the world. However, this event is incompletely documented along the Brazilian margin, despite the existence of an impressive record of Miocene deposits exposed mostly as several coastal cliffs along more than 5000 km of distance. The transgressive nature of Miocene deposits, so far recognized only in a few localities of northeastern Brazil, needs to be amplified in order to better characterize the impact of the Miocene transgression in eastern South America. In this work, we provide facies analysis of early/middle Miocene strata exposed in the Paraíba Basin, northeastern Brazil, aiming reconstruct the depositional paleoenvironments and analyze their evolution within the context of relative sea-level fluctuations data. The results revealed deposits characterized by several features that were related to the action of tidal currents, such as alternating thicker/thinner forest packages, abundant reactivation surfaces, mud drapes and oppositely-dipping (herringbone) cross sets. These sedimentary structures were associated with an ichnological assemblage indicative of marine-influenced and brackish water, best represented by Ophiomorpha, Planolites-Palaeophycus-Thalassinoides and Thallassinoides-Planolites-Palaeophycus ichnofabrics. Sedimentation occurred in environments consisting of estuarine channel, estuarine central basin, tidal inlet/tidal channel, tidal delta/washover, tidal flat/shoal and foreshore, which were related to an estuarine setting, at least in part of a wave-dominated type. Analysis of facies stratal patterns led to suggest that the estuarine deposits of the Paraíba Basin reflect a rise in relative sea level probably during the transgressive and/or highstand stage of a depositional sequence formed directly overlying Cretaceous rocks. This rise can be correlated with the worldwide early/mid Miocene marine transgression. However, while the eustatic sea

  5. Evaluating extreme flood characteristics of small mountainous basins of the Black Sea coastal area, Northern Caucasus

    Directory of Open Access Journals (Sweden)

    L. S. Lebedeva

    2015-06-01

    Full Text Available The probability of heavy rains and river floods is expected to increase with time in the Northern Caucasus region. Densely populated areas in the valleys of small mountainous watersheds already frequently suffer from catastrophic peak floods caused by intense rains at higher elevations. This study aimed at assessing the flood characteristics of several small basins in the piedmont area of the Caucasus Mountains adjacent to the Black Sea coast including ungauged Cemes River in the Novorossiysk city. The Deterministic-Stochastic Modelling System which consists of hydrological model Hydrograph and stochastic weather generator was applied to evaluate extreme rainfall and runoff characteristics of 1% exceedance probability. Rainfall intensity is shown to play more significant role than its depth in formation of extreme flows within the studied region.

  6. Composition and natural history notes of the coastal snake assemblage from Northern Bahia, Brazil

    Science.gov (United States)

    Marques, Ricardo; Mebert, Konrad; Fonseca, Érica; Rödder, Dennis; Solé, Mirco; Tinôco, Moacir Santos

    2016-01-01

    Abstract Information about the snake diversity and their natural history from the Atlantic forest domain in Brazil refer mostly to inland forests than to coastal region. Within the state of Bahia, this knowledge is concentrated to the southeastern coastal stretch. Herein we report on the diversity of snakes from the restinga, ombrophilous forest and anthropogenic environment from the northern Atlantic coast of Bahia. We sampled nine sites for three years and visited four museum collections. Furthermore, we provide anecdotal natural history information, voucher analyses, literature complements, and a key to fascilitate species identification. We report a total of 774 snakes belonging to 50 species and 23 new distribution records for northeastern coast of Bahia, supplemented by new data on feeding and reproduction. The number of detected species is similar to numbers obtained in comparable studies from other Brazilian ecoregions. This study reports and focuses for the first time on all known species of snakes from the northeastern coast of Bahia. PMID:27594800

  7. Composition and natural history notes of the coastal snake assemblage from Northern Bahia, Brazil.

    Science.gov (United States)

    Marques, Ricardo; Mebert, Konrad; Fonseca, Érica; Rödder, Dennis; Solé, Mirco; Tinôco, Moacir Santos

    2016-01-01

    Information about the snake diversity and their natural history from the Atlantic forest domain in Brazil refer mostly to inland forests than to coastal region. Within the state of Bahia, this knowledge is concentrated to the southeastern coastal stretch. Herein we report on the diversity of snakes from the restinga, ombrophilous forest and anthropogenic environment from the northern Atlantic coast of Bahia. We sampled nine sites for three years and visited four museum collections. Furthermore, we provide anecdotal natural history information, voucher analyses, literature complements, and a key to fascilitate species identification. We report a total of 774 snakes belonging to 50 species and 23 new distribution records for northeastern coast of Bahia, supplemented by new data on feeding and reproduction. The number of detected species is similar to numbers obtained in comparable studies from other Brazilian ecoregions. This study reports and focuses for the first time on all known species of snakes from the northeastern coast of Bahia.

  8. Strontium isotopic signature of groundwater from Adamantina aquifer, Bauru Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Maldaner, Carlos [Centre for Applied Groundwater Research, University of Guelph, 50 Stone Rd, Guelph, ON, N1G 2W1 (Canada); Martins, Veridiana; Bertolo, Reginaldo; Hirata, Ricardo [Centro de Pesquisas de Aguas Subterraneas do Instituto de Geociencias da Universidade de Sao Paulo, Sao Paulo - SP (Brazil)

    2013-07-01

    Using {sup 87}Sr/{sup 86}Sr ratios and the geochemistry of groundwater we were able to identify different hydrochemical facies in the Adamantina aquifer, Bauru Basin (Brazil). Samples from shallow wells show Cl-NO{sub 3}-Ca-Mg water with low pH due to natural and anthropogenic recharge. The {sup 87}Sr/{sup 86}Sr ratios are greatest in the shallower parts of the aquifer (0.7134) and decrease with increasing well screen interval depth. The nitrate concentration gradually decreases with depth and aquifer pH increases, HCO{sub 3} predominates as the main anion, and the groundwater becomes saturated with respect to calcite, with average {sup 87}Sr/{sup 86}Sr ratios of 0.708694 at depth. (authors)

  9. Geochemical evaluation of marginal basins in the south of Bahia state, Brazil

    International Nuclear Information System (INIS)

    Gaglianone, P.C.; Trindade, L.A.F.; Nascimento, M.M. do

    1987-01-01

    Geochemical analyses were performed on more than 700 rock samples and 4 oil samples, from Mucuri, Cumuruxatiba and Jequitinhonha basins, offshore Bahia state, Brazil. The methods employed in this study includes the evaluation of organic carbon contents, Rock-Eval pyrolysis, vitrinite reflectance, carbon isotopes, assessment of oils and extrats by liquid and gas chromatography and gas chromatography - spectrometry. Three main source rock systems have been identified in offshore Bahia: the Mucuri shales from Rio da Serra and Aratu Stages lower Neocomian related to a lacustrine fresh water environment; the Jiquia shales (Upper Neocomian) deposited in a lacustrine saline water environment, and the Alagoas Shales related to an evaporitic environment of Aptian age. (author) [pt

  10. Trends in the development and updating of the fishing fleet in the Northern Basin

    Directory of Open Access Journals (Sweden)

    Kuranov Yu. F.

    2017-12-01

    Full Text Available The practice and need to update and form the production and technical base of fishery enterprises have an increasing impact on performance of the fisheries complex and become decisive when considering the prospects for its development on an innovative basis. The paper examines the current state and development trends of the Northern Basin fishing fleet, its production capabilities in developing available bioresources, the need and prospects for renewal. During the research the influence of the main factors determining the formation of the quantitative and structural composition of the fishing fleet has been shown. The most stable and long-term impact is the state of commercial stocks of aquatic biological resources, their variability under the influence of natural factors and anthropogenic load. The second important factor is institutional changes. Initially, since the beginning of the 1990s, this took place due to the transformation of economic relations, and later – to institutional changes in the legislatively approved principles of granting fishing enterprises the right to access water biological resources. The following data have been presented: adaptation of the fleet's production capacities for specialization of fishing activities, ways of modernization and re-equipment, construction of new vessels, acquisition of vessels being in operation in the countries with developed fisheries. These changes had reduced the fleet's production potential raising its qualitative indicators (productivity, depth of processing of raw materials at sea. At the same time, the noted positive trends have been accompanied by some increase in the aging indicators for all groups and types of vessels. The institutional and economic instruments for supporting and stimulating the construction of new fishing vessels have been justified. Nowadays, in the Northern Basin the priority areas of support should be the construction of ships for pelagic fishing and coastal

  11. Soil moisture behavior in an experimental basin in Northeast of brazil - the case of Guaraira river basin

    Science.gov (United States)

    Moura Ramos Filho, Geraldo; das Neves Almeida, Cristiano; da Silva Freitas, Emerson

    2017-04-01

    In 2003, a hydrological network of the semiarid region (REHISA in Portuguese) was created in Brazil. Since then, experimental watersheds in this region have been providing hydro meteorological data collected in automatic gauges. One of these basins is the Guaraíra river basin, which is operated and maintained by the Federal University of Paraíba. This experimental watershed is located in the coastal region of Paraíba state, where the average annual rainfall is 1.700 mm. According to Köppen its climate is tropical with dry summer, and the drainage area is 5,84 km2. At this experimental basin four rainfall and one climate gauges were installed in 2003. In all of these gauges the soil moisture is monitored hourly with a Time Domain Reflectometry probe representing the 30 cm layer. According to previous analysis the spatial distribution of rainfall in the experimental basin is very low and also soil texture, which is sandy. However, the land use is different and the behavior of the soil moisture is also different. Thus, this paper present part of a study that tries to understand the difference between two gauges, in terms of soil moisture. In order to do this, two years data base were used of different gauges, gauges 2 and 4. In the first part of the study, just the descendent part of the soil moisture curve were used. Different data periods were select from a peak to a stabilization point and then the soil moisture Drying Rate (DR) was calculated to show the speed that a peak reaches the stabilization point. The data analysis was carried out considering the whole data together, then the data were shared into dry and wet periods. The results show that for the gauge 2 the DR range from 0.0335 to 2.772x10-3 kg/kg.h, with an average of 0.632x10-3 kg/kg.h. On the other hand, the gauge 4 present values that range from 0.0139 to 3.617x10-3 kg/kg.h, with an average of 0.375x10-3 kg/kg.h. As can be seen, both gauges presented different DR. When the data set is share into

  12. Differential proteomic analysis of noncardia gastric cancer from individuals of northern Brazil.

    Science.gov (United States)

    Leal, Mariana Ferreira; Chung, Janete; Calcagno, Danielle Queiroz; Assumpção, Paulo Pimentel; Demachki, Samia; da Silva, Ismael Dale Cotrim Guerreiro; Chammas, Roger; Burbano, Rommel Rodríguez; de Arruda Cardoso Smith, Marília

    2012-01-01

    Gastric cancer is the second leading cause of cancer-related death worldwide. The identification of new cancer biomarkers is necessary to reduce the mortality rates through the development of new screening assays and early diagnosis, as well as new target therapies. In this study, we performed a proteomic analysis of noncardia gastric neoplasias of individuals from Northern Brazil. The proteins were analyzed by two-dimensional electrophoresis and mass spectrometry. For the identification of differentially expressed proteins, we used statistical tests with bootstrapping resampling to control the type I error in the multiple comparison analyses. We identified 111 proteins involved in gastric carcinogenesis. The computational analysis revealed several proteins involved in the energy production processes and reinforced the Warburg effect in gastric cancer. ENO1 and HSPB1 expression were further evaluated. ENO1 was selected due to its role in aerobic glycolysis that may contribute to the Warburg effect. Although we observed two up-regulated spots of ENO1 in the proteomic analysis, the mean expression of ENO1 was reduced in gastric tumors by western blot. However, mean ENO1 expression seems to increase in more invasive tumors. This lack of correlation between proteomic and western blot analyses may be due to the presence of other ENO1 spots that present a slightly reduced expression, but with a high impact in the mean protein expression. In neoplasias, HSPB1 is induced by cellular stress to protect cells against apoptosis. In the present study, HSPB1 presented an elevated protein and mRNA expression in a subset of gastric cancer samples. However, no association was observed between HSPB1 expression and clinicopathological characteristics. Here, we identified several possible biomarkers of gastric cancer in individuals from Northern Brazil. These biomarkers may be useful for the assessment of prognosis and stratification for therapy if validated in larger clinical study

  13. Differential proteomic analysis of noncardia gastric cancer from individuals of northern Brazil.

    Directory of Open Access Journals (Sweden)

    Mariana Ferreira Leal

    Full Text Available Gastric cancer is the second leading cause of cancer-related death worldwide. The identification of new cancer biomarkers is necessary to reduce the mortality rates through the development of new screening assays and early diagnosis, as well as new target therapies. In this study, we performed a proteomic analysis of noncardia gastric neoplasias of individuals from Northern Brazil. The proteins were analyzed by two-dimensional electrophoresis and mass spectrometry. For the identification of differentially expressed proteins, we used statistical tests with bootstrapping resampling to control the type I error in the multiple comparison analyses. We identified 111 proteins involved in gastric carcinogenesis. The computational analysis revealed several proteins involved in the energy production processes and reinforced the Warburg effect in gastric cancer. ENO1 and HSPB1 expression were further evaluated. ENO1 was selected due to its role in aerobic glycolysis that may contribute to the Warburg effect. Although we observed two up-regulated spots of ENO1 in the proteomic analysis, the mean expression of ENO1 was reduced in gastric tumors by western blot. However, mean ENO1 expression seems to increase in more invasive tumors. This lack of correlation between proteomic and western blot analyses may be due to the presence of other ENO1 spots that present a slightly reduced expression, but with a high impact in the mean protein expression. In neoplasias, HSPB1 is induced by cellular stress to protect cells against apoptosis. In the present study, HSPB1 presented an elevated protein and mRNA expression in a subset of gastric cancer samples. However, no association was observed between HSPB1 expression and clinicopathological characteristics. Here, we identified several possible biomarkers of gastric cancer in individuals from Northern Brazil. These biomarkers may be useful for the assessment of prognosis and stratification for therapy if validated in

  14. Cryptosporidium spp. and Giardia sp. in aquatic mammals in northern and northeastern Brazil.

    Science.gov (United States)

    Borges, João Carlos; Lima, Danielle Dos; da Silva, Edson Moura; Moreira, André Lucas de Oliveira; Marmontel, Miriam; Carvalho, Vitor Luz; Amaral, Rodrigo de; Lazzarini, Stella Maris; Alves, Leucio Câmara

    2017-09-20

    Cryptosporidium and Giardia are protozoans that can infect humans and wild and domestic animals. Due to the growing importance of diseases caused by protozoan parasites in aquatic species, we aimed to evaluate the frequency of infection by Cryptosporidium spp. and Giardia sp. in aquatic and marine mammals in the northern and northeastern regions of Brazil. We collected 553 fecal samples from 15 species of wild-ranging and captive aquatic mammals in northern and northeastern Brazil. All samples were analyzed by the Kinyoun technique for identification of Cryptosporidium spp. oocysts. Giardia sp. cysts were identified by means of the centrifugal-flotation technique in zinc sulfate solution. Subsequently, all samples were submitted for direct immunofluorescence testing. The overall frequency of infection was 15.55% (86/553) for Cryptosporidium spp. and 9.04% (50/553) for Giardia sp. The presence of Cryptosporidium spp. was detected in samples from 5 species: neotropical river otter Lontra longicaudis (15.28%), giant otter Pteronura brasiliensis (41.66%), Guiana dolphin Sotalia guianensis (9.67%), Amazonian manatee Trichechus inunguis (16.03%), and Antillean manatee T. manatus (13.79%). Giardia sp. was identified in L. longicaudis (9.23%), P. brasiliensis (29.16%), pygmy sperm whale Kogia breviceps (100%), dwarf sperm whale K. sima (25%), S. guianensis (9.67%), T. inunguis (3.81%), and T. manatus (10.34%). This is the first report of Cryptosporidium spp. in L. longicaudis, P. brasiliensis, and S. guianensis, while the occurrence of Giardia sp., in addition to the 2 otter species, was also identified in manatees, thus extending the number of hosts susceptible to these parasitic agents.

  15. Tectonics vs. Climate efficiency in triggering detrital input in sedimentary basins: the Po Plain-Venetian-Adriatic Foreland Basin (Northern Italy)

    Science.gov (United States)

    Amadori, Chiara; Di Giulio, Andrea; Toscani, Giovanni; Lombardi, Stefano; Milanesi, Riccardo; Panara, Yuri; Fantoni, Roberto

    2017-04-01

    The relative efficiency of tectonics respect to climate in triggering erosion of mountain belts is a classical but still open debate in geosciences. The fact that data both from tectonically active and inactive mountain regions in different latitudes, record a worldwide increase of sediment input to sedimentary basins during the last million years concomitantly with the cooling of global climate and its evolution toward the modern high amplitude oscillating conditions pushed some authors to conclude that Pliocene-Pleistocene climate has been more efficient than tectonics in triggering mountain erosion. Po Plain-Venetian-Adriatic Foreland System, made by the relatively independent Po Plain-Northern Adriatic Basin and Venetian-Friulian Basin, provides an ideal case of study to test this hypothesis and possibly quantify the difference between the efficiency of the two. In fact it is a relatively closed basin (i.e. without significant sediment escape) with a fairly continuous sedimentation (i.e. with a quite continuous sedimentary record) completely surrounded by collisional belts (Alps, Northern Apennines and Dinarides) that experienced only very weak tectonic activity since Calabrian time, i.e. when climate cooling and cyclicity increased the most. We present a quantitative reconstruction of the sediment flow delivered from the surrounding mountain belts to the different part of the basin during Pliocene-Pleistocene time. This flow was obtained through the 3D reconstruction of the Venetian-Friulian and Po Plain Northern Adriatic Basins architecture, performed by means of the seismic-based interpretation and time-to-depth conversion of six chronologically constrained surfaces (seismic and well log data from courtesy of ENI); moreover, a 3D decompaction of the sediment volume bounded by each couple of surfaces has been included in the workflow, in order to avoid compaction-related bias. The obtained results show in both Basins a rapid four-folds increase of the

  16. Sommerxylon spiralosus from Upper Triassic in southernmost Paraná Basin (Brazil: a new taxon with taxacean affinity

    Directory of Open Access Journals (Sweden)

    Etiene F. Pires

    2004-09-01

    Full Text Available The anatoical description of silici?ed Gymnospermae woods from Upper Triassic sequences of southernmost Paraná Basin (Brazil has allowed the identi?cation of a new taxon: Sommerxylon spiralosus n.gen. et n.sp. Diagnostic parameters, such as heterocellular medulla composed of parenchymatous and sclerenchymatous cells, primary xylem endarch, secondary xylem with dominant uniseriate bordered pits, spiral thickenings in the radial walls of tracheids, medullar rays homocellular, absence of resiniferous canals and axial parenchyma, indicate its relationship with the family Taxaceae, reporting on the first recognition of this group in the Triassic on Southern Pangea. This evidence supports the hypothesis that the Taxaceae at the Mesozoic were not con?ned to the Northern Hemisphere.A descrição anatômica de lenhos silicificados de Gymnospermae em seqüência do Triássico Superior no sul da Bacia do Paraná (Brasil, possibilitou a identificação de um novo taxon: Sommerxylon spiralosus n.gen. et n.sp. Parâmetros diagnósticos tais como medula heterocelular, composta por células parenquimáticas e esclerenquimáticas, xilema primário endarco, xilema secundário com pontoações areoladas unisseriadas dominantes, espessamentos espiralados nas paredes radiais dos traqueídeos, raios lenhosos homocelulares, ausência de canais resiníferos e de parênquima axial, indicam a sua vinculação à família Taxaceae, constituindo-se em reconhecimento inédito da presença deste grupo no Triássico Superior no sul do Pangea. Esta evidência suporta a hipótese de que a família Taxaceae não estava confinada ao Hemisfério Norte durante o Mesozóico.

  17. Radon measurements along active faults in the Langadas Basin, northern Greece

    Directory of Open Access Journals (Sweden)

    C. Papastefanou

    2001-01-01

    Full Text Available A network of three radon stations has been established in the Langadas Basin, northern Greece for radon monitoring by various techniques in earthquake prediction studies. Specially made devices with plastic tubes including Alpha Tracketch Detectors (ATD were installed for registering alpha particles from radon and radon decay products exhaled from the ground, every 2 weeks, by using LR-115, type II, non-strippable Kodak films, starting from December 1996. Simultaneous measurements started using Lucas cells alpha spectrometer for instantaneous radon measurements in soil gas, before and after setting ATDs at the radon stations. Continuous monitoring of radon gas exhaling from the ground started from the middle of August 1999 by using silicon diode detectors, which simultaneously register meteorological parameters, such as rainfall, temperature and barometric pressure. The obtained data were studied together with the data of seismic events, such as the magnitude, ML, of earthquakes that occurred at the Langadas Basin during the period of measurements, as registered by the Laboratory of Geophysics, Aristotle University of Thessaloniki, in order to find out any association between them.

  18. Histophilus somni-induced thrombotic meningoencephalitis in cattle from northern Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Selwyn A. Headley

    2015-04-01

    Full Text Available Thrombotic meningoencephalitis (TME is a fatal neurological disease of cattle, predominantly from North America, that is caused by Histophilus somni with sporadic descriptions from other countries. This manuscript describes the occurrence of spontaneous TME in cattle from northern Paraná, Brazil. Most cattle had acute neurological manifestations characteristic of brain dysfunction. Hematological and cerebrospinal fluid analyses were not suggestive of bacterial infections of the brain. Histopathology revealed meningoencephalitis with vasculitis and thrombosis of small vessels that contained discrete neutrophilic and/or lymphocytic infiltrates admixed with fibrin at the brainstem, cerebral cortex, and trigeminal nerve ganglion of all animals. All tissues from the central nervous system used during this study were previously characterized as negative for rabies virus by the direct immunofluorescence assay. PCR and RT-PCR assays investigated the participation of infectious agents associated with bovine neurological disease by targeting specific genes of H. somni, Listeria monocytogenes, bovine herpesvirus -1 and -5, bovine viral diarrhea virus, and ovine herpesvirus-2. PCR and subsequent sequencing resulted in partial fragments of the 16S rRNA gene of H. somni from brain sections of all animals with histopathological diagnosis of TME; all other PCR/RT-PCR assays were negative. These findings confirmed the participation of H. somni in the neuropathological disease observed in these animals, extend the geographical distribution of this disease, and support previous findings of H. somni from Brazil.

  19. Source identification of fine-grained suspended sediment in the Kharaa River basin, northern Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Theuring, Philipp [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany); Collins, Adrian L. [Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton, Devon EX20 2SB (United Kingdom); Rode, Michael [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany)

    2015-09-01

    Fine sediment inputs into river systems can be a major source of nutrients and heavy metals and have a strong impact on water quality and ecosystem functions of rivers and lakes, including those in semiarid regions. However, little is known to date about the spatial distribution of sediment sources in most large scale river basins in Central Asia. Accordingly, a sediment source fingerprinting technique was used to assess the spatial sources of fine-grained (< 10 μm) sediment in the 15 000 km{sup 2} Kharaa River basin in northern Mongolia. Variation in geochemical composition (e.g. in Ti, Sn, Mo, Mn, As, Sr, B, U, Ca and Sb) was used for sediment source discrimination with geochemical composite fingerprints based on Genetic Algorithm (GA)-driven Discriminant Function Analysis, the Kruskal–Wallis H-test and Principal Component Analysis. All composite fingerprints yielded a satisfactory GOF (> 0.97) and were subsequently used for numerical mass balance modelling with uncertainty analysis. The contributions of the individual sub-catchment spatial sediment sources varied from 6.4% (the headwater sub-catchment of Sugnugur Gol) to 36.2% (the Kharaa II sub-catchment in the middle reaches of the study basin), generally showing higher contributions from the sub-catchments in the middle, rather than the upstream, portions of the study area. The importance of river bank erosion is shown to increase from upstream to midstream tributaries. The source tracing procedure provides results in reasonable accordance with previous findings in the study region and demonstrates the applicability and associated uncertainties of the approach for fine-grained sediment source investigation in large scale semi-arid catchments. - Highlights: • Applied statistical approach for selecting composite fingerprints in Mongolia. • Geochemical fingerprinting for the definition of source areas in semiarid catchment. • Test of applicability of sediment sourcing in large scale semi-arid catchments

  20. Impacts of the active layer on runoff in an upland permafrost basin, northern Tibetan Plateau.

    Science.gov (United States)

    Gao, Tanguang; Zhang, Tingjun; Guo, Hong; Hu, Yuantao; Shang, Jianguo; Zhang, Yulan

    2018-01-01

    The paucity of studies on permafrost runoff generation processes, especially in mountain permafrost, constrains the understanding of permafrost hydrology and prediction of hydrological responses to permafrost degradation. This study investigated runoff generation processes, in addition to the contribution of summer thaw depth, soil temperature, soil moisture, and precipitation to streamflow in a small upland permafrost basin in the northern Tibetan Plateau. Results indicated that the thawing period and the duration of the zero-curtain were longer in permafrost of the northern Tibetan Plateau than in the Arctic. Limited snowmelt delayed the initiation of surface runoff in the peat permafrost in the study area. The runoff displayed intermittent generation, with the duration of most runoff events lasting less than 24 h. Precipitation without runoff generation was generally correlated with lower soil moisture conditions. Combined analysis suggested runoff generation in this region was controlled by soil temperature, thaw depth, precipitation frequency and amount, and antecedent soil moisture. This study serves as an important baseline to evaluate future environmental changes on the Tibetan Plateau.

  1. Spatial distribution of pelagic fish larvae in the northern main basin of Lake Huron

    Science.gov (United States)

    Roseman, Edward F.; O'Brien, Timothy P.

    2013-01-01

    Larval fish occurrence in inshore and offshore zones in the northern main basin of Lake Huron was assessed during 2007 as part of a larger ecological examination of Lake Huron foodwebs and habitats. Day and night collections using neuston and conical nets at inshore (1.5–15 m depths) and offshore (37 and 91 m depths) locations at De Tour and Hammond Bay to assess the abundance, phenology, and spatial distribution of pelagic ichthyoplankton during spring and early summer were made. In general, densities of larval fishes were higher at De Tour than Hammond Bay during daytime neuston net collections, with the exception of Longnose Sucker, which were only collected at Hammond Bay. Lake Whitefish, Burbot, and Rainbow Smelt dominated inshore catches in early spring with Cisco, Deepwater Sculpin, Emerald Shiner, Bloater, Slimy Sculpin, Ninespine Stickleback, and Yellow Perch larvae also collected.Nighttime nearshore and offshore sampling revealed that Rainbow Smelt and Burbot larvae were present in relatively high abundances compared to inshore densities. Concentrations of larvae of deepwater demersal fishes such as Lake Whitefish and Deepwater Sculpin suggest that inshore zones in northern Lake Huron are important nursery habitats emphasizing a critical production and recruitment linkage between inshore and deepwater zones.

  2. Metal contamination in benthic macroinvertebrates in a sub-basin in the southeast of Brazil

    Directory of Open Access Journals (Sweden)

    WAC Chiba

    Full Text Available Benthic macroinvertebrates have many useful properties that make possible the use of these organisms as sentinel in biomonitoring programmes in freshwater. Combined with the characteristics of the water and sediment, benthic macroinvertebrates are potential indicators of environmental quality. Thus, the spatial occurrence of potentially toxic metals (Al, Zn, Cr, Co, Cu, Fe, Mn and Ni in the water, sediment and benthic macroinvertebrates samples were investigated in a sub-basin in the southeast of Brazil in the city of São Carlos, São Paulo state, with the aim of verifying the metals and environment interaction with benthic communities regarding bioaccumulation. Hypothetically, there can be contamination by metals in the aquatic environment in the city due to lack of industrial effluent treatment. All samples were analysed by the USEPA adapted method and processed in an atomic absorption spectrophotometer. The sub-basin studied is contaminated by toxic metals in superficial water, sediment and benthic macroinvertebrates. The Bioaccumulation Factor showed a tendency for metal bioaccumulation by the benthic organisms for almost all the metal species. The results show a potential human and ecosystem health risk, contributing to metal contamination studies in aquatic environments in urban areas.

  3. Instrumental Neutron Activation Analysis- INAA: environmental studies in Das Velhas Basin, Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    Rabelo V, M.A.; Andrade Q, M.T.; Araujo M, R.; Albernaz A, I.; Oliveira, A.H. de

    2006-01-01

    The Instrumental Neutron Activation Analysis - INAA was applied to determine concentrations of several elements in unpolluted areas and in the mining and farming region of the Das Velhas Basin, Minas Gerais State, Brazil. INAA was applied using the TRIGA Mark I IPR - R1 reactor at the Nuclear Technology Development Center of the National Committee of Nuclear Energy (CDTN/CNEN), in Belo Horizonte city, Minas Gerais State. At 100 kW of potency the flux of neutrons is 6.6 10 11 n.cm -2 .s -1 . The samples analyzed were: water; sediment; gravel of gold mine and forage. The obtained results for the Das Velhas Basin in water and sediment samples - mining companies region - show a high level (μg/g) of contamination with the analyzed elements, mainly in the sediment samples. During the period of floods, in farming region hundreds of kilometers away, contamination is found in fish and forage, reaching and harming both people and animals that live in the marginal region. (Author)

  4. Ostracoda (Arthropoda, Crustacea from the Riachuelo Formation, Sergipe-Alagoas Basin, Brazil, Upper Aptian-Albian

    Directory of Open Access Journals (Sweden)

    Lucas Silveira Antonietto

    2016-11-01

    Full Text Available The Sergipe-Alagoas Basin has one of the most complete, exposed lithological successions of the Cretaceous period in the continental margin of Brazil. It captures several phases of the evolution of the South Atlantic Ocean, including rift, gulf and drift. The upper Aptian–Albian Riachuelo Formation corresponds to the first stages of the southern proto-Atlantic Ocean invasion in that basin. The present study reviews the taxonomic identification and ecology of 39 ostracod species of this formation, proposing a new genus – Gabonorygma gen. nov. – and three new species – Praebythoceratina deltalata sp. nov., Gabonorygma sergipana gen. et sp. nov. and Brachycythere smithsoniana sp. nov. Other taxa include Conchoecia? sp. 1, Cytherella sp. 1, C. besrineensis comb. nov., Cytherelloidea aff. globosa, C. btaterensis, Bairdoppilata sp. 1, Bairdoppilata sp. 2, B. comanchensis comb. nov., B. pseudoseptentrionalis, Robsoniella falklandensis, Cetacella sp. 1, Paracypris eniotmetos, Harbinia sinuata?, H. crepata, Liasina sp. 1, Praebythoceratina amsittenensis comb. nov., P. trinodosa comb. nov., Patellacythere sp. 1, P. shimonensis comb. nov., Xestoleberis? sp. 1, Xestoleberis? sp. 2, Apatocythere? sp. 1, Neocythere? aff. pseudovanveeni, N. (Physocythere tenuis, Aracajuia antiqua comb. nov., A. benderi, A. fragilis comb. nov., Eocytheropteron sp. 1, Metacytheropteron aff. minuta, Microceratina? sp. 1, M. azazoulensis, Veenia guianensis, Algeriana? sp. 1, Quasihermanites? sp. 1 and Sergipella viviersae.

  5. Technical knowledge and water resources management: A comparative study of river basin councils, Brazil

    Science.gov (United States)

    Lemos, Maria Carmen; Bell, Andrew R.; Engle, Nathan L.; Formiga-Johnsson, Rosa Maria; Nelson, Donald R.

    2010-06-01

    Better understanding of the factors that shape the use of technical knowledge in water management is important both to increase its relevance to decision-making and sustainable governance and to inform knowledge producers where needs lie. This is particularly critical in the context of the many stressors threatening water resources around the world. Recent scholarship focusing on innovative water management institutions emphasizes knowledge use as critical to water systems' adaptive capacity to respond to these stressors. For the past 15 years, water resources management in Brazil has undergone an encompassing reform that has created a set of participatory councils at the river basin level. Using data from a survey of 626 members of these councils across 18 river basins, this article examines the use of technical knowledge (e.g., climate and weather forecasts, reservoir streamflow models, environmental impact assessments, among others) within these councils. It finds that use of knowledge positively aligns with access, a more diverse and broader discussion agenda, and a higher sense of effectiveness. Yet, use of technical knowledge is also associated with skewed levels of power within the councils.

  6. Sedimentary response to orogenic exhumation in the northern rocky mountain basin and range province, flint creek basin, west-central Montana

    Science.gov (United States)

    Portner, R.A.; Hendrix, M.S.; Stalker, J.C.; Miggins, D.P.; Sheriff, S.D.

    2011-01-01

    Middle Eocene through Upper Miocene sedimentary and volcanic rocks of the Flint Creek basin in western Montana accumulated during a period of significant paleoclimatic change and extension across the northern Rocky Mountain Basin and Range province. Gravity modelling, borehole data, and geologic mapping from the Flint Creek basin indicate that subsidence was focused along an extensionally reactivated Sevier thrust fault, which accommodated up to 800 m of basin fill while relaying stress between the dextral transtensional Lewis and Clark lineament to the north and the Anaconda core complex to the south. Northwesterly paleocurrent indicators, foliated metamorphic lithics, 64 Ma (40Ar/39Ar) muscovite grains, and 76 Ma (U-Pb) zircons in a ca. 27 Ma arkosic sandstone are consistent with Oligocene exhumation and erosion of the Anaconda core complex. The core complex and volcanic and magmatic rocks in its hangingwall created an important drainage divide during the Paleogene shedding detritus to the NNW and ESE. Following a major period of Early Miocene tectonism and erosion, regional drainage networks were reorganized such that paleoflow in the Flint Creek basin flowed east into an internally drained saline lake system. Renewed tectonism during Middle to Late Miocene time reestablished a west-directed drainage that is recorded by fluvial strata within a Late Miocene paleovalley. These tectonic reorganizations and associated drainage divide explain observed discrepancies in provenance studies across the province. Regional correlation of unconformities and lithofacies mapping in the Flint Creek basin suggest that localized tectonism and relative base level fluctuations controlled lithostratigraphic architecture.

  7. Landsat investigations of the northern Paradox basin, Utah and Colorado: implications for radioactive waste emplacement

    Science.gov (United States)

    Friedman, Jules D.; Simpson, Shirley L.

    1978-01-01

    The first stages of a remote-sensing project on the Paradox basin, part of the USGS (U.S. Geological Survey) radioactive waste-emplacement program, consisted of a review and selection of the best available satellite scanner images to use in geomorphologic and tectonic investigations of the region. High-quality Landsat images in several spectral bands (E-2260-17124 and E-5165-17030), taken under low sun angle October 9 and 10, 1975, were processed via computer for planimetric rectification, histogram analysis, linear transformation of radiance values, and edge enhancement. A lineament map of the northern Paradox basin was subsequently compiled at 1:400,000 using the enhanced Landsat base. Numerous previously unmapped northeast-trending lineaments between the Green River and Yellowcat dome; confirmatory detail on the structural control of major segments of the Colorado, Gunnison, and Dolores Rivers; and new evidence for late Phanerozoic reactivation of Precambrian basement structures are among the new contributions to the tectonics of the region. Lineament trends appear to be compatible with the postulated Colorado lineament zone, with geophysical potential-field anomalies, and with a northeast-trending basement fault pattern. Combined Landsat, geologic, and geophysical field evidence for this interpretation includes the sinuousity of the composite Salt Valley anticline, the transection of the Moab-Spanish Valley anticline on its southeastern end by northeast-striking faults, and possible transection (?) of the Moab diapir. Similarly, northeast-trending lineaments in Cottonwood Canyon and elsewhere are interpreted as manifestations of structures associated with northeasterly trends in the magnetic and gravity fields of the La Sal Mountains region. Other long northwesterly lineaments near the western termination of the Ryan Creek fault zone. may be associated with the fault zone separating the Uncompahgre horst uplift from the Paradox basin. Implications of the

  8. Status and understanding of groundwater quality in the northern San Joaquin Basin, 2005

    Science.gov (United States)

    Bennett, George L.; Fram, Miranda S.; Belitz, Kenneth; Jurgens, Bryant C.

    2010-01-01

    Groundwater quality in the 2,079 square mile Northern San Joaquin Basin (Northern San Joaquin) study unit was investigated from December 2004 through February 2005 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001 that was passed by the State of California and is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The Northern San Joaquin study unit was the third study unit to be designed and sampled as part of the Priority Basin Project. Results of the study provide a spatially unbiased assessment of the quality of raw (untreated) groundwater, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 61 wells in parts of Alameda, Amador, Calaveras, Contra Costa, San Joaquin, and Stanislaus Counties; 51 of the wells were selected using a spatially distributed, randomized grid-based approach to provide statistical representation of the study area (grid wells), and 10 of the wells were sampled to increase spatial density and provide additional information for the evaluation of water chemistry in the study unit (understanding/flowpath wells). The primary aquifer systems (hereinafter, primary aquifers) assessed in this study are defined by the depth intervals of the wells in the California Department of Public Health database for each study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource; and (2) understanding, identification of the natural and human factors

  9. Measurements and modelling of evapotransiration to assess agricultural water productivity in basins with changing land use patterns : a case study in the São Francisco River basin, Brazil

    NARCIS (Netherlands)

    Castro Teixeira, de A.H.

    2008-01-01

    Key words: Vineyards, mango, energy balance, evapotranspiration, water productivity, Bowen ratio, eddy correlation, water balance, natural vegetation, latent heat flux, sensible heat flux, biomass, water productivity, remote sensing, water management. . The São Francisco River basin in Brazil is

  10. Phytogeographical patterns of dry forests sensu stricto in northern Minas Gerais State, Brazil.

    Science.gov (United States)

    Arruda, Daniel M; Ferreira-Júnior, Walnir G; Duque-Brasil, Reinaldo; Schaefer, Carlos E R

    2013-01-01

    The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.

  11. Paleocene calcareous nannofossils biostratigraphy from the Sergipe Sub-basin, northeastern Brazil: Implications for this depositional environment

    Science.gov (United States)

    Andrade Oliveira, Geize Carolinne Correia; de Oliveira, Rick Souza; Monte Guerra, Rodrigo; de Lima Filho, Mario Ferreira

    2018-03-01

    This study reports on the biostratigraphy of Paleocene calcareous nannofossils and paleoenvironmental inferences based on five wells drilled on the offshore portion of the Sergipe Sub-basin. Five biostratigraphic zones were defined for the Paleocene in zones of Brazilian continental margin basins N-305, N-307, N-330, N-340 and N-350, and four hiatuses were identified based on the absence of marker species. These hiatuses were interpreted as excavations originated by turbulent to hyperpycnal flows, revealing an important application of biostratigraphy to better understand depositional environments that are often limited by little variation in lithology or low variation in the well log patterns. In Paleoecological terms, the Sergipe Sub-basin, in the Paleocene, experienced geological and environmental events similar to those of other sedimentary basins on the eastern passive continental margin of Brazil, but has a more complete biostratigraphic record of calcareous nannofossils.

  12. The MITMOTION Project - A seismic hazard overview of the Mitidja Basin (Northern Algeria)

    Science.gov (United States)

    Borges, José; Ouyed, Merzouk; Bezzeghoud, Mourad; Idres, Mouloud; Caldeira, Bento; Boughacha, Mohamed; Carvalho, João; Samai, Saddek; Fontiela, João; Aissa, Saoussen; Benfadda, Amar; Chimouni, Redouane; Yalaoui, Rafik; Dias, Rui

    2017-04-01

    The Mitidja Basin (MB) is located in northern Algeria and is filled by quaternary sediments with a length of about 100 km on the EW direction and approximately 20 km width. This basin is limited to the south by the Boumerdes - Larbaa - Blida active fault system and to the north by the Thenia - Sahel fault system. Both fault systems are of the reverse type with opposed dips and accommodate a general slip rate of 4 mm/year. This basin is associated with important seismic events that affected northern Algeria since the historical period until the present. The available earthquake catalogues reported numerous destructive earthquakes that struke different regions, such as Algiers (1365, Io= X; 1716, Io = X). Recently, on May 2003 the Bourmedes earthquake (Mw = 6.9) affected the area of Zemmouri and caused 2.271 deaths. The event was caused by the reactivation of the MB boundary faults. The epicenter was located offshore and generated a maximum uplift of 0.8 m along the coast with a horizontal maximum slip of 0.24 m. Recent studies show that the Boumerdes earthquake overloaded the system of adjacent faults with a stress increase between 0.4 and 1.5 bar. This induced an increase of the seismic hazard potential of the region and recommends a more detailed study of this fault system. The high seismogenic potential of the fault system bordering the MB, the exposure to danger of the most densely populated region of Algiers and the amplification effect caused by the basin are the motivation for this project proposal that will focus on the evaluation of the seismic hazard of the region. The general purpose of the project is to improve the seismic hazard assessment on the MB producing realistic predictions of strong ground motion caused by moderate and large earthquakes. To achieve this objective, it is important to make an effort in 3 directions: 1) the development of a detailed 3D velocity/structure model of the MB that includes geological constraints, seismic reflection data

  13. Cultural landscapes of the Araucaria Forests in the northern plateau of Santa Catarina, Brazil.

    Science.gov (United States)

    Machado Mello, Anna Jacinta; Peroni, Nivaldo

    2015-06-09

    The Araucaria Forest is associated with the Atlantic Forest domain and is a typical ecosystem of southern Brazil. The expansion of Araucaria angustifolia had a human influence in southern Brazil, where historically hunter-gatherer communities used the pinhão, araucaria's seed, as a food source. In the north of the state of Santa Catarina, the Araucaria Forest is a mosaic composed of cultivation and pasture inserted between forest fragments, where pinhão and erva-mate are gathered; some local communities denominate these forest ecotopes as caívas. Therefore, the aim of this study is to understand how human populations transform, manage and conserve landscapes using the case study of caívas from the Araucaria Forests of southern Brazil, as well as to evaluate the local ecological knowledge and how these contribute to conservation of the Araucaria Forest. This study was conducted in the northern plateau of the state of Santa Catarina, Brazil in local five communities. To assess ethnoecological perceptions the historical use and management of caívas, semi-structured interviews, checklist interviews and guided tours were conducted with family units. In total 28 family units participated in the study that had caívas on their properties. During the course of the study two main perceptions of the ecotope caíva were found, there is no consensus to the exact definition; perception of caívas is considered a gradient. In general caívas are considered to have the presence of cattle feeding on native pasture, with denser forest area that is managed, and the presence of specific species. Eleven management practices within caívas were found, firewood collection, cattle grazing, trimming of the herbaceous layer, and erva-mate extraction were the most common. Caívas are perceived and defined through the management practices and native plant resources. All participants stated that there have been many changes to the management practices within caívas and to the ca

  14. Hydrocarbon potential, palynology and palynofacies of four sedimentary basins in the Benue Trough, northern Cameroon

    Science.gov (United States)

    Bessong, Moïse; Hell, Joseph Victor; Samankassou, Elias; Feist-Burkhardt, Susanne; Eyong, John Takem; Ngos, Simon, III; Nolla, Junior Désiré; Mbesse, Cecile Olive; Adatte, Thierry; Mfoumbeng, Marie Paule; Dissombo, Edimo André Noel; Ntsama, Atangana Jacqueline; Mouloud, Bennami; Ndjeng, Emmanuel

    2018-03-01

    Organic geochemical, palynological and palynofacies analyses were carried out on 79 selected samples from four sedimentary basins (Mayo-Rey, Mayo-Oulo-Lere, Hamakoussou and Benue) in northern Cameroon. Rock-Eval pyrolysis and Total Organic Carbon results indicate that most of the samples of the studied basins are thermally immature to mature. The organic matter consists of terrestrial components (peat, lignite, bituminous coal, and anthracite) associated with organic matter of marine origin. Based on the appraisal of multiple parameters: Total Organic Carbon (TOC), maximum Temperature (T-max), Hydrogen Index (HI), Oxygen Index (OI) and Production Index (PI), some samples are organically rich both in oil and/or gas-prone kerogen Type-II, II/III and III. The source rock quality ranges from poor to very good. The source material is composed of both algae and higher plants. Samples from these basins yielded palynological residue composed of translucent and opaque phytoclasts, Amorphous Organic Matter (AOM), fungal remains, algal cysts pollen and pteridophyte spores. Abundance and diversity of the palynomorphs overall low and include Monoporopollenites annulatus (= Monoporites annulatus), indeterminate periporate pollen, indeterminate tetracolporate pollen, indeterminate tricolporate pollen, indeterminate triporate pollen, indeterminate trilete spores, Polypodiaceoisporites spp., Biporipsilonites sp., Rhizophagites sp., Striadiporites sp., Botryococcus sp. (colonial, freshwater green algae), and Chomotriletes minor (cyst of zygnematalean freshwater green algae). Age assigned confidently for all these basins the palynological data except for one sample of Hamakoussou that can be dated as Early to Mid-Cretaceous in age. Callialasporites dampieri, Classopollis spp., Eucommiidites spp. and Araucariacites australis indicate, an Aptian to Cenomanian age. The other pollen and spores recovered may indicate a Tertiary or younger age (especially Monoporopollenites annulatus), or

  15. Radionuclide levels in fish from Lake Athabasca February 1993. Northern River Basins Study project report no.26

    International Nuclear Information System (INIS)

    Smithson, G.

    1993-12-01

    The Northern River Basins Study was initiated through the 'Canada-Alberta-Northwest Territories Agreement Respecting the Peace-Athabasca-Slave River Basin Study, Phase II - Technical Studies' which was signed September 27, 1991. The purpose of the study is to understand and characterize the cumulative effects of development on the water and aquatic environment of the Study Area by coordinating with existing programs and undertaking appropriate new technical studies. This publication reports the method and findings of particular work conducted as part of the Northern River Basins Study. As such, the work was governed by a specific terms of reference and is expected to contribute information about the Study Area within the context of the overall study as described by the Study Final Report. This report has been reviewed by the Study Science Advisory Committee in regards to scientific content and has been approved by the Study Board of Directors for public release. It is explicit in the objectives of the Study to report the results of technical work regularly to the public. This objective is served by distributing project reports to an extensive network of libraries, agencies, organizations and interested individuals and by granting universal permission to reproduce the material. This report contains referenced data obtained from external to the Northern River Basins Study. Individuals interested in using external data must obtain permission to do so from the donor agency. (author). 47 refs., 9 tabs., 2 figs

  16. Radionuclide levels in fish from Lake Athabasca February 1993. Northern River Basins Study project report no.26

    Energy Technology Data Exchange (ETDEWEB)

    Smithson, G [Saskatchewan Research Council, Saskatoon, SK (Canada)

    1993-12-01

    The Northern River Basins Study was initiated through the `Canada-Alberta-Northwest Territories Agreement Respecting the Peace-Athabasca-Slave River Basin Study, Phase II - Technical Studies` which was signed September 27, 1991. The purpose of the study is to understand and characterize the cumulative effects of development on the water and aquatic environment of the Study Area by coordinating with existing programs and undertaking appropriate new technical studies. This publication reports the method and findings of particular work conducted as part of the Northern River Basins Study. As such, the work was governed by a specific terms of reference and is expected to contribute information about the Study Area within the context of the overall study as described by the Study Final Report. This report has been reviewed by the Study Science Advisory Committee in regards to scientific content and has been approved by the Study Board of Directors for public release. It is explicit in the objectives of the Study to report the results of technical work regularly to the public. This objective is served by distributing project reports to an extensive network of libraries, agencies, organizations and interested individuals and by granting universal permission to reproduce the material. This report contains referenced data obtained from external to the Northern River Basins Study. Individuals interested in using external data must obtain permission to do so from the donor agency. (author). 47 refs., 9 tabs., 2 figs.

  17. Low palaeoelevation of the northern Lhasa terrane during late Eocene: Fossil foraminifera and stable isotope evidence from the Gerze Basin.

    Science.gov (United States)

    Wei, Yi; Zhang, Kexin; Garzione, Carmala N; Xu, Yadong; Song, Bowen; Ji, Junliang

    2016-06-08

    The Lhasa terrane is a key region for understanding the paleoelevation of the southern Tibetan Plateau after India-Asia collision. The Gerze Basin, located in the northern part of the Lhasa terrane, is a shortening-related basin. We discovered Lagena laevis (Bandy) fossils in upper Eocene strata of the Gerze Basin. This type of foraminifera is associated with lagoon and estuarine environments, indicating that the northern part of the Lhasa terrane was near sea level during the late Eocene. We speculate that these foraminifera were transported inland by storm surges to low elevation freshwater lakes during times of marine transgressions. This inference is consistent with the relatively positive δ(18)O values in carbonate from the same deposits that indicate low palaeoelevations close to sea level. Considering the palaeoelevation results from the nearby Oligocene basins at a similar latitude and the volcanic history of the Lhasa terrane, we infer that large-magnitude surface uplift of the northern Lhasa terrane occurred between late Eocene and late Oligocene time.

  18. Two new species of Rineloricaria (Siluriformes: Loricariidae from the rio Iguaçu basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo F. S. Ingenito

    Full Text Available Rineloricaria langei and R. maacki, new species, are described from upper and middle regions of the rio Iguaçu basin, a left bank tributary of the rio Paraná basin, southern Brazil. Rineloricaria langei has narrow body and is similar to R. quadrensis, which is found in coastal rivers of Rio Grande do Sul State and is distinguishable by several morphometric characters. Rineloricaria maacki is distinguishable from all other congeners by the shape and extension of the naked area of the ventral region of pectoral girdle and other morphological characters. The presence of a naked region on the abdominal surface is shared with other species from the rio Paraná and rio Uruguay basins and coastal drainages from southeastern and southern Brazil. This may indicate a close phylogenetic relationship among these species. Similarities between the two new species and species from the aforementioned drainages also suggest close biogeographic relationship between the Paraná basin and other Brazilian coastal Atlantic drainages throughout the rio Iguaçu basin.

  19. Jurassic sedimentary evolution of southern Junggar Basin: Implication for palaeoclimate changes in northern Xinjiang Uygur Autonomous Region, China

    Directory of Open Access Journals (Sweden)

    Shun-Li Li

    2014-04-01

    Full Text Available Junggar Basin, located in northern Xinjiang, presents continuous and multikilometer-thick strata of the Jurassic deposits. The Jurassic was entirely terrestrial fluvial and lacustrine deltaic sedimentation. Eight outcrop sections across the Jurassic strata were measured at a resolution of meters in southern Junggar Basin. Controlling factors of sedimentary evolution and palaeoclimate changes in Junggar Basin during the Jurassic were discussed based on lithology, fossils and tectonic setting. In the Early to Middle Jurassic, the warm and wide Tethys Sea generated a strong monsoonal circulation over the central Asian continent, and provided adequate moisture for Junggar Basin. Coal-bearing strata of the Badaowan, Sangonghe, and Xishanyao Formations were developed under warm and humid palaeoclimate in Junggar Basin. In the late Middle Jurassic, Junggar Basin was in a semi-humid and semi-arid environment due to global warming event. Stratigraphy in the upper part of the Middle Jurassic with less plant fossils became multicolor or reddish from dark color sediments. During the Late Jurassic, collision of Lhasa and Qiangtang Block obstructed monsoon from the Tethys Sea. A major change in climate from semi-humid and semi-arid to arid conditions took place, and reddish strata of the Upper Jurassic were developed across Junggar Basin.

  20. Well successfully drilled with high performance water-based fluid: Santos Basins, offshore Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Fornasier, Frank C.; Luzardo, Juan P. [Halliburton Company, Houston, TX (United States); Bishnoi, M.L. [Oil and Natural Gas Corporation Ltda. (ONGC), Dehradun (India)

    2012-07-01

    Santos Basin is a 352,260 square kilometers (136,010 sq mi) offshore pre-salt basin. It is located in the South Atlantic Ocean, some 300 kilometers (190 mi) South East of Sao Paulo, Brazil. One of the largest Brazilian sedimentary basins, it is the site of several recent significant oil fields, including Tupi and Jupiter. The criteria for drilling fluid selection is based upon the following factors: maximum cost efficiency, environmental friendliness, optimum borehole stability, and ease of use. The recommended drilling fluid formulation takes into consideration the experience gained during the drilling of wells in the Santos Basin area. The operator wanted to use a high-performance water-based fluid (HPWBF) that could provide shale inhibition, wellbore stability, lubricity and improved rate of penetration (ROP) as an alternative to synthetic-based drilling fluids to present value in terms of economics and environmental friendliness. The HPWBF consists of three synergistic products: a hydration suppressant, a dispersion suppressant, and an accretion suppressant. The system is formulated based on customized solutions for managing the clay reactivity. High logistics costs require drilling fluids that can be prepared with sea water and discharged to the sea without environmental impact. The HPWBF is a clay-free system designed for maximum shale inhibition in highly reactive formations. The system can provide wellbore stability, high rates of penetration, and acceptable rheological properties over a wide range of temperatures, with the added benefit of allowing cuttings discharge based upon water base environmental restrictions. Since no oil is used in the formulation, the HPWBF eliminates the need for cuttings processing and monitoring equipment, and exceeds the environmental requirements by achieving an LC50 value of 345,478.22 ppm in comparison with the minimum requirement (LC50 > 30,000 ppm in 96 hr), permitting use and discharge to the sea. The HPWBF selected

  1. Geomorphic evolution of the San Luis Basin and Rio Grande in southern Colorado and northern New Mexico

    Science.gov (United States)

    Ruleman, Chester A.; Machette, Michael; Thompson, Ren A.; Miggins, Dan M; Goehring, Brent M; Paces, James B.

    2016-01-01

    The San Luis Basin encompasses the largest structural and hydrologic basin of the Rio Grande rift. On this field trip, we will examine the timing of transition of the San Luis Basin from hydrologically closed, aggrading subbasins to a continuous fluvial system that eroded the basin, formed the Rio Grande gorge, and ultimately, integrated the Rio Grande from Colorado to the Gulf of Mexico. Waning Pleistocene neotectonic activity and onset of major glacial episodes, in particular Marine Isotope Stages 11–2 (~420–14 ka), induced basin fill, spillover, and erosion of the southern San Luis Basin. The combined use of new geologic mapping, fluvial geomorphology, reinterpreted surficial geology of the Taos Plateau, pedogenic relative dating studies, 3He surface exposure dating of basalts, and U-series dating of pedogenic carbonate supports a sequence of events wherein pluvial Lake Alamosa in the northern San Luis Basin overflowed, and began to drain to the south across the closed Sunshine Valley–Costilla Plain region ≤400 ka. By ~200 ka, erosion had cut through topographic highs at Ute Mountain and the Red River fault zone, and began deep-canyon incision across the southern San Luis Basin. Previous studies indicate that prior to 200 ka, the present Rio Grande terminated into a large bolson complex in the vicinity of El Paso, Texas, and systematic, headward erosional processes had subtly integrated discontinuously connected basins along the eastern flank of the Rio Grande rift and southern Rocky Mountains. We propose that the integration of the entire San Luis Basin into the Rio Grande drainage system (~400–200 ka) was the critical event in the formation of the modern Rio Grande, integrating hinterland basins of the Rio Grande rift from El Paso, Texas, north to the San Luis Basin with the Gulf of Mexico. This event dramatically affected basins southeast of El Paso, Texas, across the Chisos Mountains and southeastern Basin and Range province, including the Rio

  2. PALEOENVIRONMENTAL EVOLUTION OF THE ITARARÉ GROUP (PARANÁ BASIN IN THE REGIONS OF SALTO AND ITU, EAST OF SÃO PAULO STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Sérgio Bergamaschi

    2016-03-01

    Full Text Available Itararé Group represents the glacial record of Gondwana Continent in the intracratonic Paraná Basin, encompassing regions of Southern Brazil, Eastern Paraguay, Northeast Argentina and Northern Paraguay. Itararé Group is the thickest sedimentary package of Paraná Basin, and was deposited over 36 million years during the end of the Carboniferous and the beginning of the Permian. However, in relation to its paleoenvironmental evolution, it is generally understood that more research is necessary, in order to better understand the genesis of the Itararé Group in different places. The present work entailed mapping facies associations for the Itararé Group in the city of Salto, in São Paulo State, by identifying and classifying sedimentary facies that, in turn, were utilized to develop a paleoenvironmental evolution model. This model was based on geological mapping carried out over 125 km². Petrological and petrographic descriptions of 32 outcrops of Itararé Group also were studied. These results were compared with subsurface data obtained by Sistema de Informações de Águas Subterrâneas, Serviços Geológicos do Brasil (SIAGAS-CPRM; System Water Information Groundwater, Geological Survey of Brazil. Through lithofacies and petrographic analyses and making a comparison between five column sections, surface and subsurface data, a stratigraphic correlation model was established for the region. Through this model was possible to identify four facies associations, which, together, indicate how the paleoenvironmental evolution of the region occurred. The first three associations (A, B, C were interpreted as being formed in subaqueous environment, being related to sandy lobe systems, followed by the last association (D, pertaining to a fluvial system.

  3. Thick sedimentary sequence around Bahraich in the northern part of the central Ganga foreland basin

    Science.gov (United States)

    Manglik, A.; Adilakshmi, L.; Suresh, M.; Thiagarajan, S.

    2015-06-01

    We present the results of a magnetotelluric study along a 285 km long profile between Hamirpur and Rupadia (Nepal border) across the central Ganga basin. The electrical resistivity image obtained by combining 1-D Occam inversion models for 39 sites reveals a significant contrast in the subsurface structure from south to north along the profile. At the southern end, the Bundelkhand massif is delineated as a high resistivity block buried beneath 250-300 m thick sediments. The thickness of sediments gradually increases to about 500-600 m at Kanpur, and to about 1.2 km at Lucknow. Here, the basement depth increases to more than 2.5 km within a profile distance of 20 km, which could be attributed to the Lucknow fault. The underlying rocks also have moderate resistivity and possibly represent the Vindhyans. The sedimentary sequence at the northern end of the profile around Bahraich is more than 9 km thick. Integrating the resistivity image with a published seismic velocity structure from the region and the lithology from the 3927 m deep Matera-I well reveals that the top 4 km succession is constituted of highly conductive Oligocene and younger rocks of the Matera Formation and the Siwaliks, and recent sediments whereas the underlying > 5 km section is composed of sedimentary rocks of the Bahraich Group overlying the Archean basement. The high conductivity of sediments in conjunction with the low seismic velocity and large Vp/Vs obtained by receiver function analysis implies poor consolidation of sediments and thus high seismic hazard potential. The present results have implications for hydrocarbon exploration, hazard potential scenario of the central Ganga basin, and flexural strength of the Indian Plate.

  4. Spatial and temporal variability of groundwater recharge in Geba basin, Northern Ethiopia

    Science.gov (United States)

    Yenehun, Alemu; Walraevens, Kristine; Batelaan, Okke

    2017-10-01

    WetSpa, a physically based, spatially distributed watershed model, has been used to study the spatial and temporal variation of recharge in the Geba basin, Northern Ethiopia. The model covers an area of about 4, 249 km2 and integrates elevation, soil and land-use data, hydrometeorological and river discharge data. The Geba basin has a highly variable topography ranging from 1000 to 3280 m with an average slope of 12.9%. The area is characterized by a distinct wet and long dry season with a mean annual precipitation of 681 mm and temperatures ranging between 6.5 °C and 32 °C. The model was simulated on daily basis for nearly four years (January 1, 2000 to December 18, 2003). It resulted in a good agreement between measured and simulated streamflow hydrographs with Nash-Sutcliffe efficiency of almost 70% and 85% for, respectively, the calibration and validation. The water balance terms show very strong spatial and temporal variability, about 3.8% of the total precipitation is intercepted by the plant canopy; 87.5% infiltrates into the soil (of which 13% percolates, 2.7% flows laterally off and 84.2% evapotranspired from the root zone), and 7.2% is surface runoff. The mean annual recharge varies from about 45 mm (2003) to 208 mm (2001), with average of 98.6 mm/yr. On monthly basis, August has the maximum (73 mm) and December the lowest (0.1 mm) recharge. The mean annual groundwater recharge spatially varies from 0 to 371 mm; mainly controlled by the distribution of rainfall amount, followed by soil and land-use, and to a certain extent, slope. About 21% of Geba has a recharge larger than 120 mm and 1% less than 5 mm.

  5. Ruiniform relief in sandstones: the examples of Vila Velha, Carboniferous of the Paraná Basin, Southern Brazil

    OpenAIRE

    DE MELO, M.S.; COIMBRA, A.M.

    1996-01-01

    Vila Velha is a remarkable group of natural sculptures in Palaeozoicsandstones of the Paraná. Basin in Southern Brazil. The sculptures,which resemble the ruins of an old stone city, have resulted from thecombination of Cenozoic weathering and erosive processes with the existing attributes of the sedimentary rocks (texture, cementing oxides,sedimentary and brittle structures). A particular geomorphologic settingwith eroded inselbergs, and a differential iron and manganese cementationduring lat...

  6. Diversity and distribution Patterns of the infralittoral green macroalgae from Potiguar basin, Rio Grande do Norte, Northeastern Brazil

    OpenAIRE

    Cocentino,Adilma de Lourdes Montenegro; Fujii,Mutue Toyota; Reis,Thiago Nogueira de Vasconcelos; Guimarães-Barros,Nathalia Cristina; Rocha,Marcia de França; Neumann-Leitão,Sigrid

    2010-01-01

    Diversity and distribution pattern of the infralittoral green macroalgae at Potiguar basin, Rio Grande do Norte, Northeastern Brazil were analyzed from material collected at depths varying from 2 to 100 m. Collections were carried out with two types of dredges during four campaigns: July 2002, May and November 2003 and May 2004 at 43 stations. Chlorophyta is represented by 54 species, five varieties and three forms. The most representative family is Caulerpaceae, and the most diverse genus is...

  7. Peat accumulation in drained thermokarst lake basins in continuous, ice-rich permafrost, northern Seward Peninsula, Alaska

    Science.gov (United States)

    Jones, Miriam C.; Grosse, Guido; Jones, Benjamin M.; Anthony, Katey Walter

    2012-01-01

    Thermokarst lakes and peat-accumulating drained lake basins cover a substantial portion of Arctic lowland landscapes, yet the role of thermokarst lake drainage and ensuing peat formation in landscape-scale carbon (C) budgets remains understudied. Here we use measurements of terrestrial peat thickness, bulk density, organic matter content, and basal radiocarbon age from permafrost cores, soil pits, and exposures in vegetated, drained lake basins to characterize regional lake drainage chronology, C accumulation rates, and the role of thermokarst-lake cycling in carbon dynamics throughout the Holocene on the northern Seward Peninsula, Alaska. Most detectable lake drainage events occurred within the last 4,000 years with the highest drainage frequency during the medieval climate anomaly. Peat accumulation rates were highest in young (50–500 years) drained lake basins (35.2 g C m−2 yr−1) and decreased exponentially with time since drainage to 9 g C m−2 yr−1 in the oldest basins. Spatial analyses of terrestrial peat depth, basal peat radiocarbon ages, basin geomorphology, and satellite-derived land surface properties (Normalized Difference Vegetation Index (NDVI); Minimum Noise Fraction (MNF)) from Landsat satellite data revealed significant relationships between peat thickness and mean basin NDVI or MNF. By upscaling observed relationships, we infer that drained thermokarst lake basins, covering 391 km2 (76%) of the 515 km2 study region, store 6.4–6.6 Tg organic C in drained lake basin terrestrial peat. Peat accumulation in drained lake basins likely serves to offset greenhouse gas release from thermokarst-impacted landscapes and should be incorporated in landscape-scale C budgets.

  8. Trophic state and microorganisms community of major sub-basins of the middle Rio Doce basin, southeast Brazil

    Directory of Open Access Journals (Sweden)

    Mauricio Mello Petrucio

    2005-07-01

    Full Text Available Total phosphorus concentration was used to define the trophic state of the main sub-basins of the middle Rio Doce, in Minas Gerais State (southeast Brazil and physical, chemical, and microbiological variables of water were analyzed during 2000 to 2001. The study evaluated changes in water quality caused by seasonality and human activities. Water temperature, conductivity, pH, total alkalinity, dissolved oxygen, and concentrations of NH4-N, NO2-N, NO3-N, total-N, PO4-P, total-P, DOC, and chlorophyll-a were measured in seven rivers stretches (sampling stations. Total yeasts, faecal and total coliforms, and heterotrophic bacteria were also determined. The studied areas were considered to be under oligotrophic to eutrophic conditions. The variables that presented highest positive correlation with faecal coliforms were total-P and total-N, and heterotrophic bacteria density was identified as a good parameter to differentiate the ecosystems. These results suggested the inclusion of the trophic level and the distinct activities within a watershed as important elements when proposing conservation and restoration areas.A concentração de fósforo total foi utilizada para determinar o grau de trofia das principais sub-bacias do trecho médio da bacia do Rio Doce, em Minas Gerais, e variáveis físicas, químicas e microbiológicas da água foram analisadas nos períodos de chuva e seca durante os anos de 2000 e 2001. O estudo visou determinar mudanças na qualidade da água causadas pela sazonalidade e por diferentes atividades antrópicas. As áreas estudadas variaram de oligotróficas a eutróficas. As variáveis que apresentaram as maiores correlações positivas com a densidades de coliformes fecais foram as concentrações de nitrogênio e fósforo total, além disso, bactérias heterotróficas mostrou-se capaz de diferenciar os ambientes. Estes resultados sugerem a inclusão do grau de trofia e da caracterização das atividades antrópicas na

  9. The ethnoecological knowledge of fishermen from three coastal lagoons in the northern of the State of Rio de Janeiro, Brazil

    OpenAIRE

    Lopes, Alexandre Ferreira; Bozelli, Reinaldo Luiz

    2014-01-01

    The current study investigated the ethnoecological knowledge developed by fishermen through their fishing activities and searched for ways to match such knowledge to empirical data available in the scientific literature. The research involved fishermen from three coastal lagoons in the northern region of the State of Rio de Janeiro, Brazil, who were consulted through semi-structured interviews after the establishment of a trustful relationship over a period of three years with the interviewer...

  10. Chemical oceanography of the Arabian Sea: Part III - Studies on nutrient fraction and stoichiometric relationship in the Northern and the Eastern Basins

    Digital Repository Service at National Institute of Oceanography (India)

    SenGupta, R.; Sankaranarayanan, V.N.; DeSousa, S.N.; Fondekar, S.P.

    Phosphorus and inorganic nitrogen compounds have been divided into 'reserved' andoxidative fractions based on their relationships with apparent oxygen utilization in the northern and the north-eastern basins of the Arabian Sea.Two oxygen minima...

  11. Detection of brucellosis in water buffaloes for exportation in northern and northeastern of Brazil

    Directory of Open Access Journals (Sweden)

    José Diomedes Barbosa

    2016-11-01

    Full Text Available ABSTRACT. Barbosa J.D., Bomjardim H.dosA., Lima D.H.daS., Reis A.dosS.B., Barboza F.B., Albernaz T.T., Oliveira C.M.C., Fonseca A.H., Nicolino R.R. & da Silva J.B. Detection of brucellosis in water buffaloes for exportation in northern and northeastern of Brazil. [Detecção de brucelose em búfalos d’agua para exportação no norte e nordeste do Brasil}. Revista Brasileira de Medicina Veterinária, 38(supl. 3: 129-135, 2016. Laboratório de Doenças Parasitárias, Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural de Rio de Janeiro, BR 465, Km 7 Seropédica, RJ 23890-000, Brazil. E-mail: adivaldofonseca@yahoo.com The prevalence of brucellosis in buffaloes was evaluated by the Buffered Acidified Plate Antigen (BAPA in 5.163 water buffaloes from Maranhão state, Pará state and Marajó Island, Brazil. The detection of buffaloes positive for brucellosis by BAPA was 7.37% in Marajó Island, 8.45% in Pará state and 29.86% in Maranhão state. The locations with the highest prevalences were Santa Cruz do Arari, in Marajó Island (12.50%; Ipixuna, in Pará state (30.25%; and Santa Inês, in Maranhão state (34.76%. After the confirmatory test (Complement Fixation Test, only 7 animals remained positive in Marajó Island, and 22 remained positive in the state of Pará. None of the 66 animals that reacted positively in the BAPA test in Maranhão reacted positively in the CF. The high prevalence of B. abortus that was observed in animals, especially in the state of Maranhão, is worrisome for the health system for the control and eradication of bovine brucellosis.

  12. Impact of Climatic Variability on Hydropower Reservoirs in the Paraiba Basin, Southeast of Brazil

    Science.gov (United States)

    Barros, A.; simoes, s

    2002-05-01

    During 2000/2001, a severe drought greatly reduced the volume of water available to Brazilian hydropower plants and lead to a national water rationing plan. To undestand the potential for climatic change in hydrological regimes and its impact on hydropower we chose the Paraiba Basin located in Southeast Brazil. Three important regional multi-purpose reservoirs are operating in this basin. Moreover, the Paraiba River is of great economic and environmental importance and also constitutes a major corridor connecting the two cities of Sao Paulo and Rio de Janeiro. We analyzed monthly and daily records for rainfall, streamflow and temperature using regression and variance analysis. Rainfall records do not show any significant trend since the 1930s/1940s. By contrast, analysis of seasonal patterns show that in the last twenty years rainfall has increased during autumn and winter (dry season) and decreased during spring and summer (rainy season). Comparison between rainfall and streaflow, from small catchment without man-made influences, shows a more pronounced deficit in streamflow when compared with rainfall. The shifts in seasonal rainfall could indicate a tendency towards a more uniform rainfall pattern and could serve to reduce the streamflow. However, the largest upward trends in temperature were found in the driest months (JJA). The increase in rainfall would not be sufficient to overcome increased of evaporation expect to the same period. Instead, such increase in evaporation could create an over more pronounced streamflow deficit. Climatic variability could be reducing water availability in these reservoirs especially in the driest months. To reduce the uncertainties in hydrological predictions, planners need to incorporate climatic variability, at the catchment scale, in order to accomodate the new conditions resulting from these changes.

  13. Formulation of fracture gradient extension equations in the Sergipe Basin-Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Suzart, J. Walter P.; Moreto, Rodrigo [Halliburton, Rio de Janeiro, RJ (Brazil); Luduvice, Roberto; Gomes, Isaac Santana; Richard Junior, Emerson [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    One of the challenges of drilling exploration wells is to accurately estimate fracture gradients. This may cause formation damage and lead to premature hydraulic fracturing and prevent an optimum hydraulic design during completion. To avoid this scenario, it is important to know the minimum pressure that causes fractures. This estimation may be based on density, overburden, Poisson's ratio, and minimum horizontal stress. It is now possible to monitor fracturing stimulation operations in real time, which allows real-time understanding of formation pressure response, including fracture extension behavior and screen out. It is possible to avoid risks related to unexpected high pressure applied on the formation while drilling and maintain well and equipment integrities. This may prevent non-productive time (NPT) caused by unplanned well-cleaning operations and material expenses. Real-time fracturing information is usually obtained from step-rate and/or mini-frac analyses. However, there are some scenarios where these tests and analyses may be uneconomical. This paper details an alternative solution. It uses modified Eaton's equations that are representative of the area of interest, which in the present case is the Sergipe Basin located in northeast Brazil. The modified Eaton's equations are used to estimate parameters of the minimum horizontal stress, fracture extension gradient, overburden, and Poisson's ratio. This is based on hydraulic fracturing jobs and density logs available from different locations within the Sergipe Basin. To validate the present method, the estimation results were compared with available step-rate test results for the area. (author)

  14. Joint Interpretation of Magnetotellurics and Airborne Electromagnetics in the Rathlin Basin, Northern Ireland

    Science.gov (United States)

    Delhaye, Robert; Rath, Volker; Jones, Alan G.; Reay, Derek; The Iretherm Team

    2015-04-01

    In this study we present results from geophysical investigation of the sedimentary Rathlin Basin in Northern Ireland in order to assess the potential for low-to-medium enthalpy geothermal aquifers within the porous Permian and Triassic sandstone groups. The area and groups were identified as a potential geothermal resource due to the presence of both an elevated geothermal gradient (observed in two deep boreholes onshore) and favourable hydraulic properties (measured on core samples in the offshore part of the basin). Previous seismic experiments were not able to fully characterise the sediments beneath the overlying flood basalt. Complementing these earlier results, magnetotelluric data were acquired on a grid of 56 sites across the north-eastern portion of the onshore Rathlin Basin, and an additional 12 sites on the nearby Rathlin Island, in order to image the thickness, depth, and lateral continuity of the target sediments. Analysis and 3D modelling, including the effects of the highly conducting ocean, has been successful in deriving a resistivity model that maps the variation in the top of the sediments (base of the basalts) and the truncation of the basin sediments against the Tow Valley Fault, and gives a reasonable estimate of the thickness of the sediment fill. However, the resulting models show significant effects from distortion caused by near-surface inhomogeneities in the responses that cannot be resolved using the given frequency range and site density. Fortunately, for the area of Rathlin Basin, airborne electromagnetic data from the TELLUS project (http://www.bgs.ac.uk/gsni/tellus/contact/index.html) are available. These data were measured at four frequencies between 0.9 kHz and 25 kHz in a verical-coplanar loop configuration, with the dipole axis in flight direction. The spatial sampling distance was less than 25 m, with about 200 m distance between flight lines. Survey altitudes vary between 56 m and 244 m. Thus, for the top ˜100 m penetrated by

  15. Preliminary study of the uranium potential of the northern part of the Durham Triassic Basin, North Carolina

    International Nuclear Information System (INIS)

    Harris, W.B.; Thayer, P.A.

    1981-09-01

    This report presents results of a four-channel spectrometric survey of the northern part of the Durham Triassic basin and adjacent Piedmont, North Carolina. Gamma-ray spectrometric measurements were obtained at 112 localities from 136 different lithologies. The nominal sampling density in the Durham Basin is one site per 2 mi 2 . Surface radiometric surveys reveal no anomalous radioactivity in the northern part of the Durham Basin. Uranium concentrations in Triassic rocks are from 0.6 to 9.7 ppM and average 2.9 ppM. Mudrocks contain from 1.3 to 9.7 ppM, and the average is 4.5 ppM. Sandstones contain from 0.6 to 8.8 ppM, and the average is 2.5 ppM. Fanglomerates contain the lowest concentrations of uranium, from 1.4 to 2.0 ppM, for an average of 1.8 ppM. Uranium/thorium ratios average 0.27 for Triassic rocks and are from 0.04 to 1.85. The mean log uranium/log thorium for Triassic rocks is 0.37. Mudrock has the highest average uranium/thorium ratio (0.32), and the range is 0.09 to 0.66. Sandstones have an average uranium/thorium ratio of 0.26, and the range is 0.04 to 1.85. Fanglomerates have the lowest range uranium/thorium ratio (0.19), and the range is 0.12 to 0.19. On the basis of surface radiometric surveys and geologic studies, it is believed that sedimentary strata in the northern part of the Durham Basin are poor targets for further uranium exploration. This conclusion is based on the lack of favorable characteristics commonly present in fluvial uranium deposits. Among these are: (1) carbonaceous material is absent in Triassic rocks of the northern basin, (2) indicators of a reduzate facies in sandstones are not present, and (3) no tuffaceous beds are associated with sediments in the northern Durham Basin

  16. Range extension of Moenkhausia oligolepis (Günther,1864 to the Pindaré river drainage, of Mearim river basin, and Itapecuru river basin of northeastern Brazil (Characiformes: Characidae

    Directory of Open Access Journals (Sweden)

    Erick Cristofore Guimarães

    2016-08-01

    Full Text Available The present study reports range extansion of Moenkhausia oligolepis to the Pindaré river drainage, of the Mearim river basin, and Itapecuru river basin, Maranhão state, northeastern Brazil. This species was previously known only from Venezuela, Guianas, and the Amazon River basins. In addition, we present some meristic and morphometric data of the specimens herein examined and discuss on its diagnostic characters.

  17. Geology and coal-bed methane resources of the northern San Juan Basin, Colorado and New Mexico

    International Nuclear Information System (INIS)

    Fassett, J.E.

    1988-01-01

    This guidebook is the first of its kind: A focused look at coal-bed methane in a large Rocky Mountain Laramide basin. The papers in this volume cover every aspect of coal-bed methane in the San Juan Basin, including: The geology, environments of deposition, and geometry of the coal beds that contain the resource; the origin and migration history of the gas; basin-wide resource estimates; the engineering aspects of getting the gas out of the ground; the marketing and economics of producing coal-bed methane in the San Juan Basin; the legal ownership of the gas; state regulations governing well spacing and field rules; disposal of produced water; and land and mineral ownership patterns in the northern part of the basin. Also included are detailed papers on all of the major coal-bed methane fields in the basin, and in a paper on the history of Fruitland gas production, a discussion of most of the not-so-major fields. A small section of the book deals with geophysical methods, as yet still experimental, for surface detection of underground hydrocarbon resources. Individual papers have been processed separately for inclusion on the data base

  18. Circulation of the thermocline salinity maximum waters off the Northern Brazil as inferred from in situ measurements and numerical results

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.C. [Universidade Federal do Ceara, Fortaleza, CE (Brazil). Inst. de Ciencias do Mar; Bourles, B. [Inst. de Recherche pour le Developpement, Cotonou (Benin); Araujo, M. [UFPE, Recife, PE (Brazil). Lab. de Oceanografia Fisica Estuarina e Costeira

    2009-07-01

    High resolution hydrographic observations of temperature and salinity are used to analyse the subsurface circulation along the coast of North Brazil, off the Amazon mouth, between 2 S and 6 N. Observations are presented from four cruises carried out in different periods of the year (March-May 1995, May-June 1999, July-August 2001 and October-November 1997). Numerical model outputs complement the results of the shipboard measurements, and are used to complete the descriptions of mesoscale circulation. The Salinity Maximum Waters are here analyzed, principally in order to describe the penetration of waters originating in the Southern Hemisphere toward the Northern Hemisphere through the North Brazil Current (NBC)/North Brazil Undercurrent (NBUC). Our results show that, if the Equatorial Undercurrent (EUC) is fed by Northern Atlantic Waters, this contribution may only occur in the ocean interior, east of the western boundary around 100 m depth. Modeling results indicate a southward penetration of the Western Boundary Undercurrent (WBUC) below the thermocline, along the North Brazilian coast into the EUC or the North Equatorial Undercurrent (NEUC) (around 48 W-3 N). The WBUC in the region does not flow more south than 3 N. The northern waters are diverted eastward either by the NBC retroflection or by the northern edge of the associated clockwise rings. The existence of subsurface mesoscale rings associated to the NBC retroflection is evidenced, without any signature in the surface layer, so confirming earlier numerical model outputs. These subsurface anticyclones, linked to the NBC/NBUC retroflection into the North Equatorial Undercurrent and the EUC, contribute to the transport of South Atlantic high salinity water into the Northern Hemisphere. (orig.)

  19. Thermal maturity of northern Appalachian Basin Devonian shales: Insights from sterane and terpane biomarkers

    Science.gov (United States)

    Hackley, Paul C.; Ryder, Robert T.; Trippi, Michael H.; Alimi, Hossein

    2013-01-01

    To better estimate thermal maturity of Devonian shales in the northern Appalachian Basin, eleven samples of Marcellus and Huron Shale were characterized via multiple analytical techniques. Vitrinite reflectance, Rock–Eval pyrolysis, gas chromatography (GC) of whole rock extracts, and GC–mass spectrometry (GCMS) of extract saturate fractions were evaluated on three transects that lie across previously documented regional thermal maturity isolines. Results from vitrinite reflectance suggest that most samples are immature with respect to hydrocarbon generation. However, bulk geochemical data and sterane and terpane biomarker ratios from GCMS suggest that almost all samples are in the oil window. This observation is consistent with the presence of thermogenic gas in the study area and higher vitrinite reflectance values recorded from overlying Pennsylvanian coals. These results suggest that vitrinite reflectance is a poor predictor of thermal maturity in early mature areas of Devonian shale, perhaps because reported measurements often include determinations of solid bitumen reflectance. Vitrinite reflectance interpretations in areas of early mature Devonian shale should be supplanted by evaluation of thermal maturity information from biomarker ratios and bulk geochemical data.

  20. Biostratigraphy, sedimentology and paleoenvironments of the northern Danube Basin: Ratkovce 1 well case study

    Directory of Open Access Journals (Sweden)

    Rybár Samuel

    2015-02-01

    Full Text Available The Ratkovce 1 well, drilled in the Blatné depocenter of the northern Danube Basin penetrated the Miocene sedimentary record with a total thickness of 2000 m. Biostratigraphically, the NN4, NN5 and NN6 Zones of calcareous nannoplankton were documented; CPN7 and CPN8 foraminifer Zones (N9, 10, 11 of the global foraminiferal zonation; and MMi4a; MMi5 and MMi6 of the Mediterranean foraminiferal zonation were recognized. Sedimentology was based on description of well core material, and together with SP and RT logs, used to characterize paleoenvironmental conditions of the deposition. Five sedimentary facies were reconstructed: (1 fan-delta to onshore environment which developed during the Lower Badenian; (2 followed by the Lower Badenian proximal slope gravity currents sediments; (3 distal slope turbidites were deposited in the Lower and Upper Badenian; (4 at the very end of the Upper Badenian and during the Sarmatian a coastal plain of normal marine to brackish environment developed; (5 sedimentation finished with the Pannonian-Pliocene shallow lacustrine to alluvial plain deposits. The provenance analysis records that the sediment of the well-cores was derived from crystalline basement granitoides and gneisses and from the Permian to Lower Cretaceous sedimentary cover and nappe units of the Western Carpathians and the Eastern Alps. Moreover, the Lower Badenian volcanism was an important source of sediments in the lower part of the sequence.

  1. Anastomosing river deposits: palaeoenvironmental control on coal quality and distribution, Northern Karoo Basin

    Energy Technology Data Exchange (ETDEWEB)

    Cairncross, B

    1980-01-01

    Borehole data from an area close to the northern margin of the Karoo Basin 110 m thick coal reveal a bearing succession of the Vryheid Formation overlying Dwyka tillite. The lowermost sediments reflect processes of deglaciation with a complex array of glaciolacustrine, glaciofluvial and alluvial-outwash fan deposits. Above this paraglacial milieu, tundra-type peat bogs developed in inactive areas and account for the two thick basal coal seams (No. 1 and 2 seams). During accumulation of peat which was later to form the extensive No. 2 coal seam, active clastic sedimentation was confined to laterally restricted river channels which incised into the underlying peat. Lateral migration was inhibited by vegetation stabilized river banks and channel deposits are characterized by vertically accreted upward-fining cycles. Channel fill consists of coarse-grinder bedload sediment deposited in anastomosing streams. Flood episodes are marked by widespread, but thin (< 1 m), shale zones that intercalate with the channel sandstones. Both sandstone and shale units are completely enveloped by No. 2 coal seams. This clastic parting influences No. 2 coal seam distribution and ash content. 23 references

  2. Origin of an unusual heavy oil from the Baiyinchagan depression, Erlian basin, northern China

    Energy Technology Data Exchange (ETDEWEB)

    Haiping Huang [China University of Geosciences, Beijing (China); University of Newcastle, Newcastle upon Tyne (United Kingdom). School of Civil Engineering and Geosciences; Guangxi Jin [China University of Geosciences, Beijing (China); Exploration and Development Institute, Puyang (China); Changsong Lin; Yabin Zheng [China University of Geosciences, Beijing (China)

    2003-01-01

    A detailed organic geochemical analysis of six oil samples from the Baiyinchagan depression in the Erlian basin, Northern China, was carried out in order to evaluate their origin. The oils are reservoired at a very shallow depth (223-560 m subsurface) and their chemical and physical properties vary greatly, ranging from normal to extremely heavy oil. The preservation of non-biodegraded oil in such a shallow reservoir is possibly related with palaeo-pasteurization of the reservoir before uplift. Maturity difference is not the primary control on the chemical and physical properties of the oils and there is considerable geochemical evidence to suggest the additional influence of in-reservoir/post-accumulation processes such as biodegradation, water-washing and (possibly) evaporation. Whereas some oils appear to be less affected, others are moderately biodegraded up to level 4 on the [Peters and Moldowan, 1993] scale, with sterane distributions largely unaffected and 25-norhopanes undetected. Contrary to classical biodegradation, the unusual heavy oil shows little evidence of biodegradation from aliphatic components. Water-washing is suggested to be the primary process leading to its formation since the severe alteration of soluble aromatic hydrocarbons is observed. In addition, since the oils have been uplifted significantly after accumulation, evaporation and/or leakage to modify oil compositions cannot be ruled out. (author)

  3. Cross-fault pressure depletion, Zechstein carbonate reservoir, Weser-Ems area, Northern German Gas Basin

    Energy Technology Data Exchange (ETDEWEB)

    Corona, F.V.; Brauckmann, F.; Beckmann, H.; Gobi, A.; Grassmann, S.; Neble, J.; Roettgen, K. [ExxonMobil Production Deutschland GmbH (EMPG), Hannover (Germany)

    2013-08-01

    A cross-fault pressure depletion study in Upper Permian Zechstein Ca2 carbonate reservoir was undertaken in the Weser-Ems area of the Northern German Gas Basin. The primary objectives are to develop a practical workflow to define cross-fault pressures scenarios for Zechstein Ca2 reservoir drillwells, to determine the key factors of cross-fault pressure behavior in this platform carbonate reservoir, and to translate the observed cross-fault pressure depletion to fault transmissibility for reservoir simulation models. Analysis of Zechstein Ca2 cross-fault pressures indicates that most Zechstein-cutting faults appear to act as fluid-flow baffles with some local occurrences of fault seal. Moreover, there appears to be distinct cross-fault baffling or pressure depletion trends that may be related to the extent of the separating fault or fault system, degree of reservoir flow-path tortuosity, and quality of reservoir juxtaposition. Based on the above observations, a three-part workflow was developed consisting of (1) careful interpretation and mapping of faults and fault networks, (2) analysis of reservoir juxtaposition and reservoir juxtaposition quality, and (3) application of the observed cross-fault pressure depletion trends. This approach is field-analog based, is practical, and is being used currently to provide reliable and supportable pressure prediction scenarios for subsequent Zechstein fault-bounded drill-well opportunities.

  4. Paleoenvironmental reconstruction and evolution of an Upper Cretaceous lacustrine-fluvial-deltaic sequence in the Parecis Basin, Brazil

    Science.gov (United States)

    Rubert, Rogerio R.; Mizusaki, Ana Maria Pimentel; Martinelli, Agustín G.; Urban, Camile

    2017-12-01

    The Cretaceous in the Brazilian Platform records events of magmatism, tectonism and sedimentation coupled to the Gondwana breakup. Some of these events are registered as sedimentary sequences in interior basins, such as in the Cretaceous sequence of the Alto Xingu Sub-basin, Parecis Basin, Central Brazil. This article proposes the faciologic characterization and paleoenvironmental reconstruction of the Cretaceous sequence of the eastern portion of the Parecis Basin and its relation with some reactivated structures as, for instance, the Serra Formosa Arch. Based on both data from outcrops and core drillings a paleoenvironmental and evolutionary reconstruction of the sequence is herein presented. The base of the studied section is characterized by chemical and low energy clastic sedimentation of Lake Bottom and Shoreline, in a context of fast initial subsidence and low sedimentation rate. As the subsidence process decreased, a deltaic progradation became dominant with deposition in a prodelta environment, followed by a deltaic front and deltaic plain interbedded with fluvial plain, and aeolian deposition completing the sequence. The inferred Coniacian-Santonian age is based on vertebrate (fishes and notosuchians) and ostracod fossils with regional chrono-correlates in the Adamantina (Bauru Group), Capacete (Sanfranciscana Basin), and Bajo de la Carpa (Neuquén Group, in Argentina) formations. The formation of a Coniacian depocenter in the Alto Xingu Sub-basin is associated to the Turonian-Coniacian reactivation event in the Peruvian Orogenic Phase of the Andean Orogeny, with the transference of stresses to interplate setting, reactivating Proterozoic structures of the basement.

  5. Precipitation thresholds for triggering floods in Corgo hydrographic basin (Northern Portugal)

    Science.gov (United States)

    Santos, Monica; Fragoso, Marcelo

    2016-04-01

    The precipitation is a major cause of natural hazards and is therefore related to the flood events (Borga et al., 2011; Gaál et al., 2014; Wilhelmi & Morss, 2013). The severity of a precipitation event and their potential damage is dependent on the total amount of rain but also on the intensity and duration event (Gaál et al., 2014). In this work, it was established thresholds based on critical combinations: amount / duration of flood events with daily rainfall data for Corgo hydrographic basin, in northern Portugal. In Corgo basin are recorded 31 floods events between 1865 and 2011 (Santos et al., 2015; Zêzere et al., 2014). We determined the minimum, maximum and pre-warning thresholds that define the boundaries so that an event may occur. Additionally, we applied these thresholds to different flood events occurred in the past in the study basin. The results show that the ratio between the flood events and precipitation events that occur above the minimum threshold has relatively low probability of a flood happen. These results may be related to the reduced number of floods events (only those that caused damage reported by the media and produced some type of damage). The maximum threshold is not useful for floods forecasting, since the majority of true positives are below this limit. The retrospective analysis of the thresholds defined suggests that the minimum and pre warning thresholds are well adjusted. The application of rainfall thresholds contribute to minimize possible situations of pre-crisis or immediate crisis, reducing the consequences and the resources involved in emergency response of flood events. References Borga, M., Anagnostou, E. N., Blöschl, G., & Creutin, J. D. (2011). Flash flood forecasting, warning and risk management: the HYDRATE project. Environmental Science & Policy, 14(7), 834-844. doi: 10.1016/j.envsci.2011.05.017 Gaál, L., Molnar, P., & Szolgay, J. (2014). Selection of intense rainfall events based on intensity thresholds and

  6. Source of sulphur in the Ebro Basin (Northern Spain). Tertiary nonmarine evaporite deposits as evidenced by sulphur isotopes

    International Nuclear Information System (INIS)

    Birnbaum, S.J.; Coleman, D.

    1979-01-01

    The Ebro Basin is an intermontane basin, located in northern Spain, filled with Tertiary (largely Oligocene and Miocene) elastic and chemical deposits. Sulphur isotopes are utilized to determine the source of sulphur in the sulphate deposits (predominantly gypsum with accessory thenardite, mirabolite and epsomite). Data obtained from Tertiary gypsum rocks produce a range of delta 34 S values from +9.16% to + 14.02% with a mean of +13.61%. Data obtained from Triassic gypsum rocks (in source area) produce a range from +13.73% to +15.14%, with a mean of +14.66%. Values for Tertiary marine water range from +18% to +24%. These data indicate a nonmarine origin for sulpur within the Tertiary sulphate rocks. The contribution of Triassic sulphur to the groundwater system, plus varying degrees of dilution by isotopically lighter (atmospheric and sulphide) sulphur, best explains the isotopic ratios observed in the Tertiary Basin deposits. (Auth.)

  7. Oral health and feeding frequency of preschool children in a city in northern Brazil

    Directory of Open Access Journals (Sweden)

    Piero Maia Fernandes

    2014-03-01

    Oral health and healthy eating habits are related to socioeconomic and cultural conditions of the population and imply the biopsychosocial health of the individual. This study investigated the oral health and feeding frequency of children attending a daycare in the municipality of Ananindeua, Pará State, northern Brazil. This was a cross-sectional study, quantitative and qualitative, descriptive, involving the examination of the oral cavity of children and questionnaires to parents, caregivers and those responsible for the daycare. Forty-seven children aged one to six years participated in this study; most were girls (57.5%. The daycare had no specific place for tooth brushing that was performed only once daily, without flossing. It was reported by parents that 48.94% of children have never visited a dentist. On examination of the oral cavity we observed carious lesion (51.10%, dental calculus (42.55%, fluorosis (10.64% and gingivitis (2.13%. It was found that the children had 3 or more meals and had the habit of consuming cariogenic foods such as soft drinks, candy and/or gum, even not being provided by the daycare. Most of the children had at least one decayed tooth, and the daycare offered a healthy diet, but the children had the habit of eating cariogenic foods.

  8. Evolution of the Planetary Boundary Layer on the northern coast of Brazil during the CHUVA campaign

    Science.gov (United States)

    Ramos, Diogo Nunes da Silva; Fernandez, Julio Pablo Reyes; Fisch, Gilberto

    2018-05-01

    This study aims to characterize the wind and thermodynamic structure of the Planetary Boundary Layer (PBL) on the northern coast of Brazil (NCB) via the CHUVA datasets. Three synoptic conditions were present in the NCB region between March 1 and 25, 2010: a dry period, the Upper Tropospheric Cyclonic Vortex (UTCV) and the Intertropical Convergence Zone (ITCZ). Nighttime precipitation accounted for 78% of the total precipitation observed in the month, mainly during the ITCZ. In general, the surface meteorological fields were few changed by intense weather events due to proximity to the ocean and the predominant contribution of the northeasterly trade winds. There was also a weak sea breeze signal that maintained the horizontal moisture flow in the studied area. On dry days, the PBL depth was higher, drier, and warmer, resulting in stronger winds below 500 m. Moreover, trends throughout the period suggest that PBLs are near-neutral below 500 m. However, the wind variability was intensified by up to 20% due to downdrafts and higher wind shears during the deep convection mechanisms derived by UTCV. Furthermore, ITCZ mixed rainfall cooled the PBL at approximately 2 K, making it very stable according to the Richardson number classification adopted. The observed temporal and spatial scale represent challenges to the physical parameterizations used to improve numerical weather prediction models over tropical coastal areas.

  9. Forewarning system for controlling Yellow Sigatoka in Northern Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Sara de Almeida Rios

    2013-09-01

    Full Text Available This trial aimed to evaluate the Biological Forewarning System (BFS for controlling Yellow Sigatoka in Northern Minas Gerais, Brazil. It was carried out in the town of Nova Porteirinha. One tested 7 treatments, using 6 gross sum (GS values (1,000; 1,300; 1,600; 1,900; 2,200, and 2,500 and the systematic disease control every 15 days. The treatments were distributed into 7 plots (120 plants/plot with ‘Prata-Anã’ and 10 plants from each plot were weekly evaluated with regard to leaf emission rate and disease incidence on the leaves 2, 3 and 4. The more advanced lesion stages and their intensity were used to calculate the gross sum, which aided in decision-making for chemical control. One collected data on production and firmness, pH, and acidity analysis of fruits. For the GS 2,500 treatment, taking into account 2-year evaluation, there was a reduction from 12 to 3 applications, i.e. 75% less fungicide was applied, without loss in productivity. Therefore, one suggests, taking into account the conditions of Nova Porteirinha, the application of BFS for chemical control of Yellow Sigatoka, using the GS value of 2,500 as an indicator of the correct time to perform pulverization.

  10. Digital model of the seabed geomorphology of southern-central Espirito Santo basin and northern Campos basin; Modelo digital da geomorfologia do fundo oceanico do centro-sul da bacia do Espirito Santo e norte da bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Schreiner, Simone; Souza, Mariana Beatriz Ferraz Mendonca de; Migliorelli, Joana Paiva Robalo [Petroleo Brasileiro S. A. (PETROBRAS), Rio de Janeiro, RJ (Brazil). Unidade de Servicos de Exploracao e Producao], Emails: schreiner@petrobras.com.br, mbfms.fototerra@petrobras.com.br, joanamigli.fototerra@petrobras.com.br

    2009-05-15

    That communication brings the result of a bathymetric mosaic of converted in a digital model of the ocean topography, consisting of 17 seismic projects 3D, besides 17 multibeam bathymetry surveys of South-Central Espirito Santo Basin and Northern Campos Basin.

  11. Geoelectrical characterization by joint inversion of VES/TEM in Paraná basin, Brazil

    Science.gov (United States)

    Bortolozo, C. A.; Couto, M. A.; Almeida, E. R.; Porsani, J. L.; Santos, F. M.

    2012-12-01

    For many years electrical (DC) and transient electromagnetic (TEM) soundings have been used in a great number of environmental, hydrological and mining exploration studies. The data of both methods are interpreted usually by individual 1D models resulting in many cases in ambiguous models. This can be explained by how the two different methodologies sample the subsurface. The vertical electrical sounding (VES) is good on marking very resistive structures, while the transient electromagnetic sounding (TEM) is very sensitive to map conductive structures. Another characteristic is that VES is more sensitive to shallow structures, while TEM soundings can reach deeper structures. A Matlab program for joint inversion of VES and TEM soundings, by using CRS algorithm was developed aiming explore the best of the both methods. Initially, the algorithm was tested with synthetic data and after it was used to invert experimental data from Paraná sedimentary basin. We present the results of a re-interpretation of 46 VES/TEM soundings data set acquired in Bebedouro region in São Paulo State - Brazil. The previous interpretation was based in geoelectrical models obtained by single inversion of the VES and TEM soundings. In this work we present the results with single inversion of VES and TEM sounding inverted by the Curupira Program and a new interpretation based in the joint inversion of both methodologies. The goal is increase the accuracy in determining the underground structures. As a result a new geoelectrical model of the region is obtained.

  12. A fossil loricariid catfish (Siluriformes: Loricarioidea from the Taubaté Basin, eastern Brazil

    Directory of Open Access Journals (Sweden)

    Maria Claudia Malabarba

    Full Text Available A new loricariid catfish is described from the Tremembé Formation (Late Oligocene to Early Miocene sediments of the Taubaté Basin in eastern São Paulo State, Brazil. Taubateia paraiba, new genus and species, is based on a single specimen preserved as a ventral-side impression of an articulated partial neurocranium, dorsal elements of the pectoral girdle and anterior vertebrae. The fossil is identified as belonging to family Loricariidae based on obvious overall similarity and the presence of diagnostic derived characters such as: odontodes, dorsal margin of metapterygoid contacting lateral ethmoid, presence of mesethmoid disk (condyle, and compound pterotic-supracleithrum bone. Also, as in most loricariids, the ossified transcapular (Baudelot's ligament plus basiocciptal lateral process form a prominent transverse wall at the occiput. Other derived characters preserved in Taubateia are synapomorphies at different levels within Loricariidae, including a wide and low parasphenoid, form of pterotic-supracleithrum, shape and position of the mesethmoid disk, a triangular lateral ethmoid with expanded posterolateral corner and a rounded and low ridge articulating with the metapterygoid, and a pointed distal margin of transverse process of the Weberian compound centrum. The derived characters recognized in this fossil are a distinctive combination for diagnosing a new genus and species but not for its unambiguous placements in any of the currently recognized loricariid subfamilies.

  13. Energetic aspects and opportunities for reusing water on offshore platforms in Campos Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Victor Magalhães Duarte

    2017-09-01

    Full Text Available In the drilling and production of oil at sea, a large quantity of potable water used is most commonly transported to oil platforms using offshore supply vessels (OSVs. Sea water desalination is used as well, but only in a few oil platforms. To minimize energy consumption, water supply options were studied. The desalination of seawater and the reusing of streams of grey water and black water were evaluated and compared with the characteristics of the current supply via OSVs. In both desalination and OSV water supply options an electrolytic wastewater treatment plant is used. The objective of this study was to analyze the current situation regarding water supply on offshore platforms located in the Campos Basin, Rio de Janeiro, Brazil, and to propose measures to take advantage of opportunities to reuse water and reduce energy expenditure. Two alternative scenarios were developed that involved the reuse of water that comes from the effluent of a biological wastewater treatment plant (WWTP. Information on the logistics of supplying water to platforms was obtained through direct consultation with companies and sources in the literature. The results show that annual energy consumption (uptake, treatment, transportation, use and waste water treatment of water on offshore platforms is currently 1.89 GWh, and that a reduction of 1.8 GWh of the energy consumed can be achieved using advanced reuse treatments. Energy consumption in the water reuse treatment is more competitive than those of transport by OSVs or seawater desalination.

  14. Seasonality of macroalgal communities in a subtropical drainage basin in Paraná state, southern Brazil.

    Science.gov (United States)

    Branco, C C Z; Krupek, R A; Peres, C K

    2008-11-01

    Seasonal dynamics of macroalgal communities was analyzed monthly by samplings in three stream segments of the Pedras River Basin, mid-south region of Paraná State, southern Brazil, from April 2004 to March 2005. The seasonal fluctuations in macroalgal species richness and abundance were correlated with selected environmental variables. In general, the seasonal distribution patterns of these communities were distinct from those reported from other tropical and temperate regions, with higher macroalgal richness and abundance observed from late spring to late fall. Multiple linear regression analysis revealed that the stream variable most closely related with the temporal distribution pattern observed was temperature, which had a very similar seasonal pattern to the biological parameters. On the other hand, the floristic composition was quite diverse in the streams sampled. Among the 25 taxa identified, only two were common to the three streams whereas 15 were restricted to a single sampling site. These data indicate that, although temperature seems to be an effective relationship with global temporal pattern, particular characteristics of each stream can strongly influence the seasonal tendencies in local scale. The results of Detrended Correspondence Analysis (DCA) and Cluster Analysis corroborated this observation.

  15. Deep-water Drilliinae, Cochlespirinae and Oenopotinae (Mollusca: Gastropoda: Turridae from the Campos Basin, southeast Brazil

    Directory of Open Access Journals (Sweden)

    Raquel Medeiros Andrade Figueira

    2010-08-01

    Full Text Available Samples of a soft-bottom community from the continental slope of Campos Basin, off southeast Brazil, were obtained between 2001 and 2003 by the Research Vessel “Astro-Garoupa” with a 0.25 m2 box corer or by dredging with a Charcot dredge. A total of 177 samples were taken at depths ranging from 700 to 1950 m. Mollusks were present at all of the stations and among Gastropoda the Turridae showed the highest diversity. Within the family Cochlespirinae we found: Leucosyrinx tenoceras (Dall, 1889, L. verrillii (Dall, 1881, expanding the known distribution of the latter species farther south, and L.? subgrundifera (Dall, 1888, which is the first record of this species for the South Atlantic and the shallowest depth at which it has ever been found. Within the family Drilliinae we found Splendrillia centimata (Dall, 1889, also the first record of this species for the South Atlantic and its shallowest depth. Within the subfamily Oenopotinae we describe here three new species in the genus Oenopota Mörch, 1852: O. seraphina n. sp., O. diabula n. sp. and O. carioca n. sp.

  16. [Work-related accidents on oil drilling platforms in the Campos Basin, Rio de Janeiro, Brazil].

    Science.gov (United States)

    Freitas, C M; Souza, C A; Machado, J M; Porto, M F

    2001-01-01

    The offshore oil industry is characterized by complex systems in relation to technology and organization of work. Working conditions are hazardous, resulting in accidents and even occasional full-scale catastrophes. This article is the result of a study on work-related accidents in the offshore platforms in the Campos Basin, Rio de Janeiro State. The primary objective was to provide technical back-up for both workers' representative organizations and public authorities. As a methodology, we attempt to go beyond the immediate causes of accidents and emphasize underlying causes related to organizational and managerial aspects. The sources were used in such a way as to permit classification in relation to the type of incident, technological system, operation, and immediate and underlying causes. The results show the aggravation of safety conditions and the immediate need for public authorities and the offshore oil industry in Brazil to change the methods used to investigate accidents in order to identify the main causes in the organizational and managerial structure of companies.

  17. Seasonality of macroalgal communities in a subtropical drainage basin in Paraná state, southern Brazil

    Directory of Open Access Journals (Sweden)

    CCZ. Branco

    Full Text Available Seasonal dynamics of macroalgal communities was analyzed monthly by samplings in three stream segments of the Pedras River Basin, mid-south region of Paraná State, southern Brazil, from April 2004 to March 2005. The seasonal fluctuations in macroalgal species richness and abundance were correlated with selected environmental variables. In general, the seasonal distribution patterns of these communities were distinct from those reported from other tropical and temperate regions, with higher macroalgal richness and abundance observed from late spring to late fall. Multiple linear regression analysis revealed that the stream variable most closely related with the temporal distribution pattern observed was temperature, which had a very similar seasonal pattern to the biological parameters. On the other hand, the floristic composition was quite diverse in the streams sampled. Among the 25 taxa identified, only two were common to the three streams whereas 15 were restricted to a single sampling site. These data indicate that, although temperature seems to be an effective relationship with global temporal pattern, particular characteristics of each stream can strongly influence the seasonal tendencies in local scale. The results of Detrended Correspondence Analysis (DCA and Cluster Analysis corroborated this observation.

  18. STRATIGRAPHIC EVOLUTION, PALEOENVIRONMENTS AND HYDROCARBON POTENTIALS OF THE BENUE/DAHOMEY BASINS, NIGERIAN AND POTIGUAR/CEARA BASINS, NE BRAZIL

    International Nuclear Information System (INIS)

    Akande, S.O; Adekeye, O.A.; Oj, O.J; Erdtmann, B.D.; Koutsokous, E.I.

    2004-01-01

    The stratigraphy, facies relationship and paleoenvironment of selected West African and the Brazillian rift basins permit the recognition of at least two major petroleum systems apart from the prolific Niger Delta petroleum system. The Lower Cretaceous fluivio-lacustrine petroleum system and Upper Cretaceous to Lower Tertiary, marine dominated petroleum system. Our combined studies of the stratigraphic, structural framework, paleoenvironment and time-space relationships of the petroleum systems in the Benue/Dahomey and the Potiguar/Ceara basins indicated that rifting and subsequent drifting during the opening of the South Atlantic controlled subsidence, sediment deposition and facies associations in individual basins. Whereas in the Potiguar/Ceara basins, the best developed source rocks are within the Neomacin-Aptian fluvio- lacustrine sequence of the Pendencia and Alagamar Formations which generated reserved hydrocarbon in the Acu Formation, empirical evidence for this petroleum system in the contiguous Benue/Dahomey basins are only based on the geochemical characteristics of the lower parts of the Bima Formation and the Abeokuta Group. In contrast, the Upper Cretaceous-Lower Tertiary marine petroleum system, which is constrained by poor development of reservoirs in the Potiguar/Ceara basin is productive in the Benue/Dahomey basins where source rocks, reservoir and sealing facies occur at this interval. Considering the recent hydrocarbon discoveries of the East Niger basin, the Doba (southern Chad), the Muglad basin (southern Sudan) sourced from the fluvio-lacustrine rift sequences, we suggest that this petroleum system needs more detailed exploration and has some potentials in the Benue/Dahomey frontier basins

  19. 3D Architecture and evolution of the Po Plain-Northern Adriatic Foreland basin during Plio-Pleistocene time

    Science.gov (United States)

    Amadori, Chiara; Toscani, Giovanni; Ghielmi, Manlio; Maesano, Francesco Emanuele; D'Ambrogi, Chiara; Lombardi, Stefano; Milanesi, Riccardo; Panara, Yuri; Di Giulio, Andrea

    2017-04-01

    The Pliocene-Pleistocene tectonic and sedimentary evolution of the eastern Po Plain and northern Adriatic Foreland Basin (PPAF) (extended ca. 35,000 km2) was the consequence of severe Northern Apennine compressional activity and climate-driven eustatic changes. According with the 2D seismic interpretation, facies analysis and sequence stratigraphy approach by Ghielmi et al. (2013 and references therein), these tectono-eustatic phases generated six basin-scale unconformities referred as Base Pliocene (PL1), Intra-Zanclean (PL2), Intra-Piacenzian (PL3), Gelasian (PL4), Base Calabrian (PS1) and Late Calabrian (PS2). We present a basin-wide detailed 3D model of the PPAF region, derived from the interpretation of these unconformities in a dense network of seismic lines (ca. 6,000 km) correlated with more than 200 well stratigraphies (courtesy of ENI E&P). The initial 3D time-model has been time-to-depth converted using the 3D velocity model created with Vel-IO 3D, a tool for 3D depth conversions and then validated and integrated with depth domain dataset from bibliography and well log. Resultant isobath and isopach maps are produced to inspect step-by-step the basin paleogeographic evolution; it occurred through alternating stages of simple and fragmented foredeeps. Changes in the basin geometry through time, from the inner sector located in the Emilia-Romagna Apennines to the outermost region (Veneto and northern Adriatic Sea), were marked by repeated phases of outward migration of two large deep depocenters located in front of Emilia arcs on the west, and in front of Ferrara-Romagna thrusts on the east. During late Pliocene-early Pleistocene, the inner side of the Emilia-Romagna arcs evolved into an elongated deep thrust-top basin due to a strong foredeep fragmentation then, an overall tectono-stratigraphic analysis shows also a decreasing trend of tectonic intensity of the Northern Apennine since Pleistocene until present.

  20. Taxonomic revision of the fossil pulmonate mollusks of Itaboraí Basin (Paleocene, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Brincalepe Salvador

    2013-01-01

    Full Text Available The limestones of Itaboraí Basin (Middle Paleocene, Rio de Janeiro, Brazil, harbor a rich fossil molluscan fauna consisting exclusively of pulmonate snails, both terrestrial and freshwater. An extensive taxonomic revision of this paleofauna is conducted here. A new genus, Cortana, is described as well as two new species, Eoborus fusiforme and Gastrocopta itaboraiensis. The revised classification is as follows: Austrodiscus lopesi (Charopidae; Biomphalaria itaboraiensis (Planorbidae; "Brachypodella" britoi (Urocoptidae; Brasilennea arethusae, Brasilennea guttula, Brasilennea minor (Cerionidae; Bulimulus fazendicus, Bulimulus trindadeae, Cortana carvalhoi, Cyclodontina coelhoi, Itaborahia lamegoi, Leiostracus ferreirai, Plagiodontes aff. dentatus (Orthalicidae; Cecilioides sommeri (Ferussaciidae; Eoborus rotundus, Eoborus sanctijosephi, Eoborus fusiforme (Strophocheilidae; Gastrocopta mezzalirai, Gastrocopta itaboraiensis (Gastrocoptidae; Temesa magalhaesi (Clausiliidae. The species Strobilopsis mauryae was considered a synonym of Brasilennea arethusae; Bulimulus sommeri a synonym of Itaborahia lamegoi; and Vorticifex fluminensis a synonym of Eoborus sanctijosephi. Itaboraí Basin has the most ancient records of the families Orthalicidae, Gastrocoptidae, Ferussaciidae and Strophocheilidae. Moreover, the basin's records of Charopidae, Clausiliidae, Cerionidae, and Urocoptidae are among the most ancient in the world and, among these, those of Cerionidae, Clausiliidae and Urocoptidae deserve special attention since they are greatly removed from these families' current distribution. Additionally, Itaboraí has the most ancient records for the genera Austrodiscus, Brachypodella, Bulimulus, Cecilioides, Cyclodontina, Eoborus, Gastrocopta, Leiostracus, Plagiodontes and Temesa. There are three endemic genera in the basin: Brasilennea, Cortana and Itaborahia. Further discussion on paleobiogeography and evolution of this paleofauna is also provided.Os calc

  1. Establishment of a metallogenetic prospecting model of a pilot area in the Resende Basin - RJ, Brazil, within it's geomorphic aspects

    International Nuclear Information System (INIS)

    Bidone, E.D.; Perrin, P.; Rocha, J.A. da

    1984-01-01

    The Resende Basin lies between the Mantiqueira Mountain range which rises up to 2800m in the alcaline massif of Itatiaia - Passa Quatro in the North, and the Serra do Mar Mountain range in the South. The basin is the most casterly of a series of elongate Tertiary sedimentary basins that stretch SW to NE between Sao Paulo and Barra Mansa in the state of Rio de Janeiro, Brazil (44 0 to 47 0 West). Considering: -The economic potential represented by source rocks for the basin sediments; -the known capacity of sediments to concentrate metals when weathering, transport and deposition conditions are favorable, a geochemical analysis was done to determine; -favorable sites of uranium and thorium concentrations; -the evolution of depositional environments through integration of sedimentalogical, mineralogical, and geochemical data in order that the metallogenetic analysis promotes more efficient prospecting. The results permit a better understanding of the sedimentological and geochemical setting of Tertiary sediments in the region, as well as establish a method of rapid, inexpensive and efficient prospection that can be used in other basins of this type. (Author) [pt

  2. Denan Depression controlled by northeast-directed Olongbulak Thrust Zone in northeastern Qaidam basin: Implications for growth of northern Tibetan Plateau

    Science.gov (United States)

    Yu, Xiangjiang; Guo, Zhaojie; Zhang, Qiquan; Cheng, Xiang; Du, Wei; Wang, Zhendong; Bian, Qing

    2017-10-01

    The Denan Depression is a unique depression in the northeastern Qaidam basin, with a maximum Cenozoic sedimentary thickness of 5 km. Detailed field work, interpretation of seismic profiles and analyzation of well data were conducted to define the Cenozoic tectonic evolution of the northeastern Qaidam basin. All geological evidences indicate that the Denan Depression is controlled by the northeast-directed Olongbulak Thrust at its southern boundary. The Denan Depression grew in concert with the development of the northeast-directed Olongbulak Thrust at least since it began to accept the Xiaganchaigou Formation, supporting the early Cenozoic growth of the northern Tibetan Plateau. Surface and subsurface data both point to enhanced tectonic activity since the Quaternary in the northeastern Qaidam basin, leading to a more individual Denan Depression relative to the main Qaidam basin. The northern boundary of the Denan Depression is a passive boundary, and no foreland developed at the northern slope of the Denan Depression.

  3. Aerosol emissions from forest and grassland burnings in the southern amazon basin and central Brazil

    Science.gov (United States)

    Leslie, Alistair C. D.

    1981-03-01

    Forest and grassland clearing by means of prescribed fires in tropical areas of the world may be responsible for large inputs of fine particulates to the global atmosphere besides being a major source of trace gases. The major continents on which extensive biomass burning takes place are Africa and South America. Such agricultural practices of burning have been employed throughout man's existence, but the importance and significance of such burning relative to anthropogenic industrial emissions to the atmosphere has not until extremely recently been seriously studied. In August-September 1979 project "Brushfire 1979" took place based in Brasília, Brazil. The Air Quality Division of the National Center for Atmospheric Research made ground level and aircraft measurements of trace gases (e.g. CO 2, CO, CH 4, N 2O, H 2, CH 3Cl, COS, NO, NO 2, O 3) and Florida State University sampled ground level aerosol emissions from grass and forest burnings. Aerosols were sampled using plastic 7-stage single orifice cascade impactors and FSU type linear and circular "streakers". Long term sampling was made of regional background for total particulates (8 μmad). Short term sampling within grass or forest fires was made using impactors incorporated into portable kits containing 4 miniature 12-18 V dc Brailsford pumps and a disposable dry cell power pack. Sampling times of 5-15 min were found optimal under these conditions. Grass fires were sampled in the savannah area northeast of Brasília and forest fires in the state of Mato Grosso on the southern edge of the dryland forest of the Amazon basin. Residual ash samples were collected. All of the samples were analyzed at Florida State University using PIXE for 15-20 elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb and Sr. Computer reduction of the X-ray spectra was made using the "HEXB" program. One of the prominent features found was the large flux of small particles (<2.0 μm) from both fire

  4. The fish fauna in tropical rivers: The case of the Sorocaba river basin, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Welber Senteio Smith

    2003-09-01

    Full Text Available A survey was carried out on the fish species in the Sorocaba River basin, the main tributary of the left margin of the Tietê River, located in the State of São Paulo, Brazil. The species were collected with gill nets. After identification of the specimens, their relative abundance, weight and standard length were determined. Up to the present moment there are not any studies that focus this subject in this hydrographic basin. Fifty-three species, distributed in eighteen families and six orders were collected. Characiformes were represented by twenty-eight species, Siluriformes by seventeen species, the Gymnotiformes by three species, Perciformes and Cyprinodontiformes by two species, and the Synbranchiformes by one species. Among the collected species there were two exotic. The most abundant species were Astyanax fasciatus and Hypostomus ancistroides. In relation to total weight the most representative species were Hoplias malabaricus and Hypostomus ancistroides. Cyprinus carpio, Prochilodus lineatus, Schizodon nasutus and Hoplias malabaricus were the most representative species in relation to average weight. Largest standard length were recorded for Sternopygus macrurus, Steindachnerina insculpta, Eigenmannia aff. virescens and Cyprinus carpioSe realizó un análisis de las especies de peces de la cuenca del Río Sorocaba, el principal tributario de la margen izquierda del Río Tietê, localizado en el estado de Sao Paulo, Brasil. Las especies fueron recolectadas con redes agalleras. Luego de la identificación de los especímenes, fue determinada su abundancia relativa, peso, y longitud estandar. Hasta el presente, no hay ningún otro estudio que analice estos aspectos en dicha cuenca hidrográfica. Fueron recolectados 55 especies, distribuidas en 18 familias y 6 ordenes. Los Characiformes estuvieron representados por 28 especies, Siluriformes por 17 especies, Gymnotiformes por 3 especies, Perciformes y Cyprinodontiformes por 2 especies, y

  5. Stress state variations among the clay and limestone formations of the molasse basin of Northern Switzerland

    International Nuclear Information System (INIS)

    Vietor, Tim; Mueller, Herwig; Frieg, Bernd; Klee, Gerd

    2012-01-01

    Document available in extended abstract form only. Full text of publication follows: The design of geological repositories for radioactive waste responds to the requirements of technical feasibility and long-term safety in the context of a specific geological setting. An important aspect of the geological setting is the primary stress field. To a large extent the stress state controls repository induced effects such as the excavation damage zone and the associated potential changes in the waste isolation properties of the host rock. Therefore the measurement of the stress state receives some attention where the site selection for geological repositories focuses onto relatively weak host rocks such as clay-stones and marly shales that tend to develop a significant excavation damage zone. Measurements of the minimum stress magnitudes in a recently drilled geothermal well in the Molasse Basin of northern Switzerland have yielded a stress profile reaching from 592 m to 1455 m depth. It straddles several rock units and includes the top of the crystalline basement. The sedimentary sequence consists of Marine limestones, shales and marls unconformably covered by Tertiary rocks of the Molasse. In other parts of the basin the evaporitic rocks of the Triassic Muschelkalk formation at the base of the sedimentary layer served as a regional detachment and enabled thin skinned thrusting and the formation of the Jura Fold and Thrust Belt in the Late Miocene. The stress measurements have been performed in the open hole by Mini-frac tests. The method uses a double packer system to isolate a one meter long interval of the borehole that is then pressurized at high injection rates up to the breakdown of the formation. Repeated pressurization of the interval allows to determine the stress that acts on the newly created fracture. The total injected volume during such a test is in the range of a few litres and the size of the fracture that extends from the borehole normal to the minimum

  6. Equilibrium and Disequilibrium of River Basins: Effects on Stream Captures in Serra do Mar and Serra da Mantiqueira, Brazil

    Science.gov (United States)

    DA Silva, L. M.

    2015-12-01

    Landscapes are mainly driven by river processes that control the dynamic reorganization of networks. Discovering and identifying whether river basins are in geometric equilibrium or disequilibrium requires an analysis of water divides, channels that shift laterally or expand upstream and river captures. Issues specifically discussed include the variation of drainage area change and erosion rates of the basins. In southeastern Brazil there are two main escarpments with extensive geomorphic surfaces: Serra do Mar and Serra da Mantiqueira Mountains. These landscapes are constituted of Neoproterozoic and early Paleozoic rocks, presenting steep escarpments with low-elevation coastal plains and higher elevation interior plateaus. To identify whether river basins and river profiles are in equilibrium or disequilibrium in Serra do Mar and Serra da Mantiqueira Mountains, we used the proxy (χ), evaluating the effect of drainage area change and erosion rates. We selected basins that drain both sides of these two main escarpments (oceanic and continental sides) and have denudation rates derived from pre-existing cosmogenic isotopes data (Rio de Janeiro, Paraná and Minas Gerais). Despite being an ancient and tectonically stable landscape, part of the coastal plain of Serra do Mar Mountain in Rio de Janeiro and Paraná is in geometric disequilibrium, with water divides moving in the direction of higher χ values. To achieve equilibrium, some basins located in the continental side are retracting and disappearing, losing area to the coastal basins. On the contrary, there are some adjacent sub-basins that are close to equilibrium, without strong contrasts in χ values. The same pattern was observed in Serra da Mantiqueira (Minas Gerais state), with stream captures and river network reorganization in its main rivers. The initial results suggest a strong contrast between erosion rates in the continental and the oceanic portions of the escarpments.

  7. Conncomitant bovine viral diarrhea, mycotoxicosis, and seneciosis in cattle from northern Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Selwyn Arligton Headley

    2014-10-01

    Full Text Available This study investigated the causes of mortality in cattle from northern Paraná, southern Brazil, during which 9.5% (23/242 of Nellore cows died after clinical manifestations of uncoordinated gait, fever, transient bloody diarrhea, dyspnea, and lateral decumbency. All cattle were maintained on poor pastures, and ingested moldy silage and sprouts of Senecio brasiliensis. Serum samples (n=17 were collected for virus neutralizing (VN antibodies assays against bovine viral diarrhea virus (BVDV and bovine herpesvirus 1 (BoHV-1. Three cows were necropsied; fragment of tissue samples collected during necropsy from two cows were used in polymerase chain reaction (PCR and reverse transcription- PCR assays to identify BoHV-1 and BVDV; blood samples (n=6 were obtained for hematological and biochemical analyses. Significant gross findings of all cows included increased liver consistency, intestinal bleeding, and pulmonary hemorrhage. Histopathology revealed hepatic fibrosis, hemorrhagic enteritis, renal tubular necrosis, pulmonary hemorrhage, and widespread vasculitis. All serum samples contained VN antibodies against BoHV-1, but only four of these reacted positively to BVDV. The RTPCR assays amplified specific amplicons of the untranslated region of BVDV from tissues samples of both animals; direct sequencing and sequence analyses demonstrated that these sequences clustered within the BVDV subgenotype 1d; all PCRs were negative for BoHV-1. Toxicological analyses of the moldy silage demonstrated elevated concentrations of ochratoxin (75.94 ?g/kg. Laboratory evaluations revealed renal and hepatic dysfunctions. These findings confirmed the combined actions of BVDV-1d infection and toxicosis by mycotoxin and S. brasiliensis in cattle mortality at this farm.

  8. Soil quality indicators in a rhodic kandiudult under different uses in northern Parana, Brazil

    Directory of Open Access Journals (Sweden)

    Biana Harumi Kuwano

    2014-02-01

    Full Text Available Sustainable use of soil, maintaining or improving its quality, is one of the goals of diversification in farmlands. From this point of view, bioindicators associated with C, N and P cycling can be used in assessments of land-use effects on soil quality. The aim of this study was to investigate chemical, microbiological and biochemical properties of soil associated with C, N and P under different land uses in a farm property with diversified activity in northern Parana, Brazil. Seven areas under different land uses were assessed: fragment of native Atlantic Forest; growing of peach-palm (Bactrys gasipaes; sugarcane ratoon (Saccharum officinarum recently harvested, under renewal; growing of coffee (Coffea arabica intercropped with tree species; recent reforestation (1 year with native tree species, previously under annual crops; annual crops under no-tillage, rye (Cecale cereale; secondary forest, regenerated after abandonment (for 20 years of an avocado (Persea americana orchard. The soil under coffee, recent reforestation and secondary forest showed higher concentrations of organic carbon, but microbial biomass and enzyme activities were higher in soils under native forest and secondary forest, which also showed the lowest metabolic coefficient, followed by the peach-palm area. The lowest content of water-dispersible clay was found in the soil under native forest, differing from soils under sugarcane and secondary forest. Soil cover and soil use affected total organic C contents and soil enzyme and microbial activities, such that more intensive agricultural uses had deeper impacts on the indicators assessed. Calculation of the mean soil quality index showed that the secondary forest was closest to the fragment of native forest, followed by the peach-palm area, coffee-growing area, annual crop area, the area of recent reforestation and the sugarcane ratoon area.

  9. Analysis of longitudinal data of beef cattle raised on pasture from northern Brazil using nonlinear models.

    Science.gov (United States)

    Lopes, Fernando B; da Silva, Marcelo C; Marques, Ednira G; McManus, Concepta M

    2012-12-01

    This study was undertaken to aim of estimating the genetic parameters and trends for asymptotic weight (A) and maturity rate (k) of Nellore cattle from northern Brazil. The data set was made available by the Brazilian Association of Zebu Breeders and collected between the years of 1997 and 2007. The Von Bertalanffy, Brody, Gompertz, and logistic nonlinear models were fitted by the Gauss-Newton method to weight-age data of 45,895 animals collected quarterly of the birth to 750 days old. The curve parameters were analyzed using the procedures GLM and CORR. The estimation of (co)variance components and genetic parameters was obtained using the MTDFREML software. The estimated heritability coefficients were 0.21 ± 0.013 and 0.25 ± 0.014 for asymptotic weight and maturity rate, respectively. This indicates that selection for any trait shall results in genetic progress in the herd. The genetic correlation between A and k was negative (-0.57 ± 0.03) and indicated that animals selected for high maturity rate shall result in low asymptotic weight. The Von Bertalanffy function is adequate to establish the mean growth patterns and to predict the adult weight of Nellore cattle. This model is more accurate in predicting the birth weight of these animals and has better overall fit. The prediction of adult weight using nonlinear functions can be accurate when growth curve parameters and their (co)variance components are estimated jointly. The model used in this study can be applied to the prediction of mature weight in herds where a portion of the animals are culled before they reach the adult age.

  10. Chagas disease ecoepidemiology and environmental changes in northern Minas Gerais state, Brazil.

    Science.gov (United States)

    Vianna, Elisa Neves; Souza E Guimarães, Ricardo José de Paula; Souza, Christian Rezende; Gorla, David; Diotaiuti, Liléia

    2017-11-01

    Triatoma sordida and Triatoma pseudomaculata are frequently captured triatomine species in the Brazilian savannah and caatinga biomes, respectively, and in Brazilian domiciles. This study identified eco-epidemiological changes in Chagas disease in northern Minas Gerais state, Brazil, and considered the influence of environmental shifts and both natural and anthropogenic effects. Domicile infestation and Trypanosoma cruzi infection rates were obtained from triatomines and sylvatic reservoirs during the following two time periods: the 1980s and 2007/2008. Entomological and climatic data with land cover classification derived from satellite imagery were integrated into a geographic information system (GIS), which was applied for atmospheric correction, segmentation, image classification, and mapping and to analyse data obtained in the field. Climatic data were analysed and compared to land cover classifications. A comparison of current data with data obtained in the 1980's showed that T. sordida colonised domiciliary areas in both periods, and that T. pseudomaculata did not colonise these areas. There was a tendency toward a reduction in T. cruzi infection rates in sylvatic reservoirs, and of triatomines captured in both households and in the sylvatic environment. T. sordida populations have reduced in the sylvatic environment, while T. pseudomaculata showed an expanding trend in the region compared to counts observed in the 1980's in the sylvatic environment. This may be related to high deforestation rates as well as gradual increases in land surface temperature (LST) and temperatures along the years. Our results suggest a geographical expansion of species into new biomes as a result of anthropogenic and climatic changes that directly interfere with the reproductive and infection processes of vectors.

  11. Chagas disease ecoepidemiology and environmental changes in northern Minas Gerais state, Brazil

    Directory of Open Access Journals (Sweden)

    Elisa Neves Vianna

    Full Text Available BACKGROUND Triatoma sordida and Triatoma pseudomaculata are frequently captured triatomine species in the Brazilian savannah and caatinga biomes, respectively, and in Brazilian domiciles. OBJECTIVES This study identified eco-epidemiological changes in Chagas disease in northern Minas Gerais state, Brazil, and considered the influence of environmental shifts and both natural and anthropogenic effects. METHODS Domicile infestation and Trypanosoma cruzi infection rates were obtained from triatomines and sylvatic reservoirs during the following two time periods: the 1980s and 2007/2008. Entomological and climatic data with land cover classification derived from satellite imagery were integrated into a geographic information system (GIS, which was applied for atmospheric correction, segmentation, image classification, and mapping and to analyse data obtained in the field. Climatic data were analysed and compared to land cover classifications. RESULTS A comparison of current data with data obtained in the 1980's showed that T. sordida colonised domiciliary areas in both periods, and that T. pseudomaculata did not colonise these areas. There was a tendency toward a reduction in T. cruzi infection rates in sylvatic reservoirs, and of triatomines captured in both households and in the sylvatic environment. T. sordida populations have reduced in the sylvatic environment, while T. pseudomaculata showed an expanding trend in the region compared to counts observed in the 1980's in the sylvatic environment. This may be related to high deforestation rates as well as gradual increases in land surface temperature (LST and temperatures along the years. MAIN CONCLUSIONS Our results suggest a geographical expansion of species into new biomes as a result of anthropogenic and climatic changes that directly interfere with the reproductive and infection processes of vectors.

  12. Genesis of textural contrasts in subsurface soil horizons in the Northern Pantanal-Brazil

    Directory of Open Access Journals (Sweden)

    Alexandre Ferreira do Nascimento

    2013-10-01

    Full Text Available The Pantanal region can be characterized as a quaternary floodplain with predominant sedimentation in the form of alluvial fans. In the geomorphologic and sedimentary evolution, the avulsion process is inherent to this depositional system and its dynamics, together with surface water floods, influence soil sedimentation on this plain. The knowledge and differentiation of these two events can contribute to a better understanding of the variability of soil properties and distribution under the influence of these sedimentation processes. Therefore, this study investigated the genesis of soils in the Northern Pantanal with textural contrasts in deeper horizons and their relationship with the depositional system dynamics. We analyzed four soil profiles in the region of Barão de Melgaço, Mato Grosso State, Brazil (RPPN SESC Pantanal. Two profiles were sampled near the Rio Cuiabá (AP1 and AP4 and two near the Rio São Lourenço (AP10 and AP11. In AP11, the horizons contrast in particle size between the profile basis and the surface. In AP1, AP4 and AP10, the horizons overlaying the sand layer have similar particle size properties, mainly in terms of sand distribution. In the first case, floods (surface water seem to have originated the horizons and layers with contrasting texture. In the second case, avulsion is the most pronounced process. Therefore, the two modes can form soils with contrasting texture that are discriminable by soil morphology, based on the distinct features associated to the specific sedimentation processes.

  13. Middle and late Badenian palaeoenvironments in the northern Vienna Basin and their potential link to the Badenian Salinity Crisis

    Science.gov (United States)

    Harzhauser, Mathias; Grunert, Patrick; Mandic, Oleg; Lukeneder, Petra; Gallardo, Ángela García; Neubauer, Thomas A.; Carnevale, Giorgio; Landau, Bernard M.; Sauer, Roman; Strauss, Philipp

    2018-04-01

    Hydrocarbon exploration in the Bernhardsthal and Bernhardsthal-Sued oil fields documents an up to 2000 m thick succession of middle and upper Badenian deposits in this part of the northern Vienna Basin (Austria). Based on palaeontological analyses of core-samples, well-log data and seismic surveys we propose an integrated stratigraphy and describe the depositional environments. As the middle/late Badenian boundary is correlated with the Langhian/Serravallian boundary, the cores capture the crucial phase of the Middle Miocene Climate Transition. The middle Badenian starts with a major transgression leading to outer neritic to upper bathyal conditions in the northern Vienna Basin, indicated by Bathysiphon-assemblages and glass-sponges. A strong palaeo-relief and rapid synsedimentary subsidence accentuated sedimentation during this phase. The middle/late Badenian boundary coincides with a major drop of relative sea level by about 200 m, resulting in a rapid shift from deeper marine depositional environments to coastal and freshwater swamps. In coeval marine settings, a more than 100 m thick unit of anhydrite-bearing clay formed. This is the first evidence of evaporite precipitation during the Badenian Salinity Crisis in the Vienna Basin. Shallow lagoonal environments with diverse and fully marine mollusc and fish assemblages were established during the subsequent late Badenian re-flooding. In composition, the mollusc fauna differs considerably from older ones and is characterized by the sudden appearance of species with eastern Paratethyan affinities.

  14. Natural radionuclides in major aquifer systems of the Parana sedimentary basin, Brazil

    International Nuclear Information System (INIS)

    Bonotto, Daniel Marcos

    2011-01-01

    This paper describes the natural radioactivity of groundwater occurring in sedimentary (Bauru and Guarani) and fractured rock (Serra Geral) aquifer systems in the Parana sedimentary basin, South America that is extensively used for drinking purposes, among others. The measurements of gross alpha and gross beta radioactivity as well the activity concentration of the natural dissolved radionuclides 40 K, 238 U, 234 U, 226 Ra, 222 Rn, 210 Po and 210 Pb were held in 80 tubular wells drilled in 21 municipalities located at Sao Paulo State and its border with Mato Grosso do Sul State in Brazil. Most of the gross alpha radioactivity data were below 1 mBq/L, whereas values exceeding the gross beta radioactivity detection limit of 30 mBq/L were found. The radioelement solubility in the studied systems varied according to the sequence radon>radium>other radionuclides and the higher porosity of sandstones relatively to basalts and diabases could justify the enhanced presence of dissolved radon in the porous aquifer. The implications of the data obtained in terms of standards established for defining the drinking water quality have also been discussed. The population-weighted average activity concentration for these radionuclides was compared to the guideline value of 0.1 mSv/yr for the total effective dose and discussed in terms of the choice of the dose conversion factors. - Highlights: → Integration of distinct radiometric data acquired in groundwaters. → Radiation dose in important hydrological resources in South America. → Contribution of 226 Ra for the more accentuated radiation dose in aquifers. → Dose factors for Rn and generation of values exceeding the maximum of 0.1 mSv/yr.

  15. 2.5D Modeling of TEM Data Applied to Hidrogeological Studies in PARANÁ Basin, Brazil

    Science.gov (United States)

    Bortolozo, C. A.; Porsani, J. L.; Santos, F. M.

    2013-12-01

    The transient electromagnetic method (TEM) is used all over the world and has shown great potential in hydrological, hazardous waste site characterization, mineral exploration, general geological mapping, and geophysical reconnaissance. However, the behavior of TEM fields are very complex and is not yet fully understood. Forward modeling is one of the most common and effective methods to understand the physical behavior and significance of the electromagnetics responses of a TEM sounding. Until now, there are a limited number of solutions for the 2D forward problem for TEM. More rare are the descriptions of a three-component response of a 3D source over 2D earth, which is the so-called 2.5D. The 2.5D approach is more realistic than the conventional 2D source previous used, once normally the source cannot be realistic represented for a 2D approximation (normally source are square loops). At present the 2.5D model represents the only way of interpreting TEM data in terms of a complex earth, due to the prohibitive amount of computer time and storage required for a full 3D model. In this work we developed a TEM modeling program for understanding the different responses and how the magnetic and electric fields, produced by loop sources at air-earth interface, behave in different geoelectrical distributions. The models used in the examples are proposed focusing hydrogeological studies, once the main objective of this work is for detecting different kinds of aquifers in Paraná sedimentary basin, in São Paulo State - Brazil. The program was developed in MATLAB, a widespread language very common in the scientific community.

  16. Growth ring analysis of fossil coniferous woods from early cretaceous of Araripe Basin (Brazil

    Directory of Open Access Journals (Sweden)

    Etiene F. Pires

    2011-06-01

    Full Text Available Growth ring analysis on silicified coniferous woods from the Missão Velha Formation (Araripe Basin - Brazil has yielded important information about periodicity of wood production during the Early Cretaceous in the equatorial belt. Despite warm temperatures, dendrological data indicate that the climate was characterized by cyclical alternation of dry and rainy periods influenced by cyclical precipitations, typical of tropical wet and dry or savanna climate. The abundance of false growth rings can be attributed to both occasional droughts and arthropod damage. The present climate data agree with palaeoclimatic models that inferred summer-wet biomes for the Late Jurassic/Early Cretaceous boundary in the southern equatorial belt.A partir de análise de anéis de crescimento em lenhos de coníferas silicificadas provenientes da Formação Missão Velha(Bacia do Araripe - Brasil, obteve-se importantes informações a respeito da periodicidade de produção lenhosa duranteo início do Cretáceo, na região do equador. Apesar das estimativas de temperatura apresentarem-se elevadas, os dados dendrológicos indicam que o clima foi caracterizado pela alternância cíclica de períodos secos e chuvosos, influenciado por precipitações periódicas, típico das condições atuais de climatropical úmido e seco ou savana. A abundância de falsosanéis de crescimento pode ser atribuída tanto a secas ocasionais quanto a danos causados por artrópodes. Os dados paleoclimáticos aqui obtidos corroboram com modelos paleoclimáticos que inferem a ocorrência de um bioma de verões úmidos para o limite Neojurássico/Eocretáceo ao sul do equador.

  17. Natural radionuclides in major aquifer systems of the Parana sedimentary basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, Daniel Marcos, E-mail: danielbonotto@yahoo.com.br [Departamento de Petrologia e Metalogenia, IGCE-Instituto de Geociencias e Ciencias Exatas, UNESP-Universidade Estadual Paulista Julio de Mesquita Filho, Av. 24-A, No. 1515 - CP 178, CEP 13506-900-Rio Claro, SP (Brazil)

    2011-10-15

    This paper describes the natural radioactivity of groundwater occurring in sedimentary (Bauru and Guarani) and fractured rock (Serra Geral) aquifer systems in the Parana sedimentary basin, South America that is extensively used for drinking purposes, among others. The measurements of gross alpha and gross beta radioactivity as well the activity concentration of the natural dissolved radionuclides {sup 40}K, {sup 238}U, {sup 234}U, {sup 226}Ra, {sup 222}Rn, {sup 210}Po and {sup 210}Pb were held in 80 tubular wells drilled in 21 municipalities located at Sao Paulo State and its border with Mato Grosso do Sul State in Brazil. Most of the gross alpha radioactivity data were below 1 mBq/L, whereas values exceeding the gross beta radioactivity detection limit of 30 mBq/L were found. The radioelement solubility in the studied systems varied according to the sequence radon>radium>other radionuclides and the higher porosity of sandstones relatively to basalts and diabases could justify the enhanced presence of dissolved radon in the porous aquifer. The implications of the data obtained in terms of standards established for defining the drinking water quality have also been discussed. The population-weighted average activity concentration for these radionuclides was compared to the guideline value of 0.1 mSv/yr for the total effective dose and discussed in terms of the choice of the dose conversion factors. - Highlights: > Integration of distinct radiometric data acquired in groundwaters. > Radiation dose in important hydrological resources in South America. > Contribution of {sup 226}Ra for the more accentuated radiation dose in aquifers. > Dose factors for Rn and generation of values exceeding the maximum of 0.1 mSv/yr.

  18. Depositional Record of the Bagua Basin, Northern Peru: Implications for Climate and Tectonic Evolution of Tropical South America

    Science.gov (United States)

    Moreno, F.; George, S. W. M.; Williams, L. A.; Horton, B. K.; Garzione, C. N.

    2015-12-01

    The Andes Mountains exert critical controls on the climate, hydrology, and biodiversity of South America. The Bagua Basin, a low elevation (400-600 m) intermontane basin in northern Peru, offers a unique opportunity to study the ecological, climatic, and structural evolution of the western topographic boundary of the Amazonian foreland. Situated between the Marañon fold-thrust belt of the Western Cordillera and basement block uplifts of the Eastern Cordillera, the Bagua region contains a protracted, semi-continuous record of Triassic through Pleistocene sedimentation. Whereas Triassic-Cretaceous marine deposits were potentially related to extension and regional thermal subsidence, a Paleocene-Eocene shift to shallow marine and fluvial systems marks the onset of foreland basin conditions. Oligocene-Miocene sedimentation corresponds to a braided-meandering fluvial system with exceptional development of paleosols. In this study, we use new detrital zircon U-Pb geochronologic and oxygen stable isotopic datasets to establish a chronology of pre-Andean and Andean processes within the Bagua Basin. Detrital zircon geochronology provides constraints on when the Western and Eastern cordilleras shed sediments into the basin. Syndepositional zircons within Eocene, Oligocene and Miocene strata provide key age control for a previously poorly constrained depositional chronology. Preliminary results suggest a dramatic provenance shift in which Paleocene deposits contain almost exclusively cratonic populations (500-1600 Ma) whereas Eocene deposits show a mix of syndepositional zircons from the magmatic arc, recycled Mesozoic zircons, and cratonic zircon populations. Oxygen stable isotopes (δ18O) of carbonate nodules from Neogene paleosols will help elucidate when the Eastern Cordillera became an orographic barrier intercepting moisture from the Amazon basin to the east. Together, these records will help uncover the history of tectonics and climate interaction in tropical South

  19. Bryophyte and pteridophyte spores and other palynomorphs in quaternary marine sediments from Campos Basin, southeastern Brazil: Core BU-91-GL-05

    Directory of Open Access Journals (Sweden)

    Aline Gonçalves de Freitas

    2015-06-01

    Full Text Available This paper presents morphological descriptions and ecological data of cryptogam spores and other non-pollen palynomorphs from Quaternary sediments of Campos Basin, Rio de Janeiro, SE Brazil. The ages were derived from biostratigraphy of planktonic foraminifers and two radiocarbon dates, and suggest that sediment deposition started in the last 140,000 years BP. Thirty different types of palynomorphs were identified, described, and photographed: two bryophyte spores (sensu lato; 21 pteridophyte spores; four freshwater microalgae; onePseudoschizaea; and two microfungi. Some of the identified spores (Sphagnum, Blechnum, Cyatheaceae, Dennstaedtiaceae, Lycopodiella, Microgramma, Polypodium, Acrostichum, Pityrogramma, and Lygodium are related to the modern flora found on the northern coast of Rio de Janeiro State, at the Restinga of Jurubatiba, from vegetation types such as shrub swamp/coastal swamp formation, seasonally flooded forest, Clusia and Ericaceae woods, and disturbed vegetation. The freshwater microalgae and the microfungi are also presently recorded from the coastal lagoons of this region. The high spore concentration in slope sediments reflects the intense terrigenous influx, caused by a relative low sealevel during glacial stages. Palynological analysis suggests the presence of taxa from flooded forests and humid areas in the coastal plain during glacial and interglacial stages of the Late Pleistocene.

  20. Palynological and sedimentary analysis of the Igarapé Ipiranga and Querru 1 outcrops of the Itapecuru Formation (Lower Cretaceous, Parnaíba Basin), Brazil

    Science.gov (United States)

    Ferreira, Neila N.; Ferreira, Elizabete P.; Ramos, Renato R. C.; Carvalho, Ismar S.

    2016-03-01

    The siliciclastic sediments of the Itapecuru Formation occur in a large area of the Parnaíba Basin and its deposits crop out along the Itapecuru River, in Maranhão State, northern Brazil. The palynological analysis of the Igarapé Ipiranga and Querru 1 outcrops strata yields a rich and diversified data. The presence of index-palynofloras in assemblages allows the identification of the Complicatisaccus cearensis Zone, of Late Aptian-Early Albian age. Terrestrial palynomorphs are abundant in the assemblages, being represented by bryophytes and pteridophytes, especially perisporate trilete spores (Crybelosporites and Perotrilites), and gymnosperms and angiosperms (Afropollis and Elaterosporites). The composition of palynological assemblages suggests the presence of moist soils for both outcrops. Acritarchs were recovered in the Querru 1 outcrop, which suggest a marine setting supporting a tidal flat environment indicated by facies associations. Furthermore, reworked Paleozoic palynomorphs were observed in the Querru 1 outcrop. The microflora from Igarapé Ipiranga outcrop suggests terrestrial environment corroborating with floodplain environment indicated by facies association.

  1. Salt anticlines in the Castile-Salado evaporite sequence, northern Delaware Basin, New Mexico

    International Nuclear Information System (INIS)

    Anderson, R.Y.; Powers, D.W.

    1977-01-01

    Anticlines are more common around basin margin but are present in basin-center areas. Both Halite I and Halite II may have flowed but Halite I was movement more extensive. Depressions associated with anticlines may be due to either flowage or subsequent dissolution. Association with brine flows is common. Anticline probably was formed with mid-Cenozoic uplift and tilting of basin and with adjustments around reef margin

  2. A new species of Astyanax (Characiformes: Characidae) from Dolina Água Milagrosa, Rio Paraguai basin, Mato Grosso, Brazil.

    Science.gov (United States)

    da Graça, W J; Oliveira, C A M; Lima, F C T; da Silva, H P; Fernandes, I M

    2017-10-01

    A new species of Astyanax is described from the upper Rio Paraguai basin, Mato Grosso State, Brazil. The new species can be distinguished from congeners by having the body intensely yellowish in life (v. silvery, reddish or lightly yellow) and by morphometric and meristics traits. Astyanax dolinae n. sp. cannot be assigned to any of the Astyanax species complex currently recognized for the genus. It is only known from the Dolina Água Milagrosa, a karstic sinkhole lake, entirely fed by groundwater, surrounded by Cerrado, the savannah-like vegetation of central South America. © 2017 The Fisheries Society of the British Isles.

  3. Fish, Ribeirão do Feijão Basin, São Carlos, São Paulo, Brazil.

    Directory of Open Access Journals (Sweden)

    Silva-Souza, A. T.

    2008-01-01

    Full Text Available The Ribeirão do Feijão Basin is the main water supplier for the municipality of São Carlos, in the state of SãoPaulo, Brazil. Field work was carried out from February to November 2005, using sieves, casting nets, and drag nets. Atotal of 7,286 specimens of fish were collected, belonging to 30 species, 13 families and six orders. The richest orderwas Characiformes with 14 species, followed by Siluriformes with seven.

  4. Evaluation and prediction of oil biodegradation: a novel approach integrating geochemical and basin modeling techniques in offshore Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Baudino, Roger [YPF S.A. (Argentina); Santos, Glauce Figueiredo dos; Losilla, Carlos; Cabrera, Ricardo; Loncarich, Ariel; Gavarrino, Alejandro [RepsolYPF do Brasil, Sao Paulo, SP (Brazil)

    2008-07-01

    Oil fields accounting for a large portion of the world reserves are severely affected by biological degradation. In Brazil, giant fields of the Campos Basin are producing biodegraded oils with widely variable fluid characteristics (10 to 40 deg API) and no apparent logical distribution nor predictability. Modern geochemical techniques allow defining the level of biodegradation. When original (non-degraded) oil samples and other with varying degradation level are available it might be possible to define a distribution trend and to relate it to present day geological factors such as temperature and reservoir geometry. However, other critical factors must be taken into account. But most of all, it is fundamental to have a vision in time of their evolution. This can only be achieved through 3D Basin Models coupled with modern visualization tools. The multi-disciplinary work-flow described here integrates three-dimensional numerical simulations with modern geochemical analyses. (author)

  5. Tectonic overview map of Northern Switzerland and correlation of aquifer-seal pairs within the molasse basin

    Energy Technology Data Exchange (ETDEWEB)

    Naef, H.

    2010-07-01

    This short report for the Swiss Federal Office of Energy (SFOE) is one of a series of appendices dealing with the potential for geological sequestration of carbon dioxide in Switzerland. This report provides a graphical overview of the situation in Northern Switzerland and correlates aquifer-seal pairs within the molasse basin. The tectonic overview is based on published tectonic summary maps from Swisstopo and the Swiss National Cooperative for the Disposal of Radioactive Wastes (NAGRA). It shows the known large, near-surface structures that are relevant to CO{sub 2} sequestration. A second map shows the correlation of Aquifer-Seal pairs in the molasse basin, based on data from eight deep drillings, illustrating the lengths and thicknesses of the aquifer-seal formations evaluated for CO{sub 2} sequestration.

  6. Cheatgrass percent cover change: Comparing recent estimates to climate change − Driven predictions in the Northern Great Basin

    Science.gov (United States)

    Boyte, Stephen P.; Wylie, Bruce K.; Major, Donald J.

    2016-01-01

    Cheatgrass (Bromus tectorum L.) is a highly invasive species in the Northern Great Basin that helps decrease fire return intervals. Fire fragments the shrub steppe and reduces its capacity to provide forage for livestock and wildlife and habitat critical to sagebrush obligates. Of particular interest is the greater sage grouse (Centrocercus urophasianus), an obligate whose populations have declined so severely due, in part, to increases in cheatgrass and fires that it was considered for inclusion as an endangered species. Remote sensing technologies and satellite archives help scientists monitor terrestrial vegetation globally, including cheatgrass in the Northern Great Basin. Along with geospatial analysis and advanced spatial modeling, these data and technologies can identify areas susceptible to increased cheatgrass cover and compare these with greater sage grouse priority areas for conservation (PAC). Future climate models forecast a warmer and wetter climate for the Northern Great Basin, which likely will force changing cheatgrass dynamics. Therefore, we examine potential climate-caused changes to cheatgrass. Our results indicate that future cheatgrass percent cover will remain stable over more than 80% of the study area when compared with recent estimates, and higher overall cheatgrass cover will occur with slightly more spatial variability. The land area projected to increase or decrease in cheatgrass cover equals 18% and 1%, respectively, making an increase in fire disturbances in greater sage grouse habitat likely. Relative susceptibility measures, created by integrating cheatgrass percent cover and temporal standard deviation datasets, show that potential increases in future cheatgrass cover match future projections. This discovery indicates that some greater sage grouse PACs for conservation could be at heightened risk of fire disturbance. Multiple factors will affect future cheatgrass cover including changes in precipitation timing and totals and

  7. Prevalence of HCV infection and associated factors among illicit drug users in Breves, State of Pará, northern Brazil

    OpenAIRE

    Pacheco,Suzy Danielly Barbosa; Silva-Oliveira,Gláucia Caroline; Maradei-Pereira,Luciana Maria Cunha; Crescente,José Ângelo Barletta; Lemos,José Alexandre Rodrigues de; Oliveira-Filho,Aldemir Branco de

    2014-01-01

    Introduction: Illicit drug users (DUs) are vulnerable to hepatitis C virus (HCV) infection. The shared use of illicit drugs is the main method of HCV transmission. Methods: A cross-sectional study was conducted in Breves, in northern Brazil. We surveyed 187 DUs to determine the prevalence of and factors associated with HCV infection. Results: The prevalence of anti-HCV antibodies was 36.9%, and the prevalence of hepatitis C virus-ribonucleic acid (HCV-RNA) was 31%. Hepatitis C virus infec...

  8. Crustal structure beneath the Paleozoic Parnaíba Basin revealed by airborne gravity and magnetic data, Brazil

    Science.gov (United States)

    de Castroa, David L.; Fuck, Reinhardt A.; Phillips, Jeffrey D.; Vidotti, Roberta M.; Bezerra, Francisco H. R.; Dantas, Elton L.

    2014-01-01

    The Parnaíba Basin is a large Paleozoic syneclise in northeastern Brazil underlain by Precambrian crystalline basement, which comprises a complex lithostructural and tectonic framework formed during the Neoproterozoic–Eopaleozoic Brasiliano–Pan African orogenic collage. A sag basin up to 3.5 km thick and 1000 km long formed after the collage. The lithologic composition, structure, and role in the basin evolution of the underlying basement are the focus of this study. Airborne gravity and magnetic data were modeled to reveal the general crustal structure underneath the Parnaíba Basin. Results indicate that gravity and magnetic signatures delineate the main boundaries and structural trends of three cratonic areas and surrounding Neoproterozoic fold belts in the basement. Triangular-shaped basement inliers are geophysically defined in the central region of this continental-scale Neoproterozoic convergence zone. A 3-D gravity inversion constrained by seismological data reveals that basement inliers exhibit a 36–40.5 km deep crustal root, with borders defined by a high-density and thinner crust. Forward modeling of gravity and magnetic data indicates that lateral boundaries between crustal units are limited by Brasiliano shear zones, representing lithospheric sutures of the Amazonian and São Francisco Cratons, Tocantins Province and Parnaíba Block. In addition, coincident residual gravity, residual magnetic, and pseudo-gravity lows indicate two complex systems of Eopaleozoic rifts related to the initial phase of the sag deposition, which follow basement trends in several directions.

  9. SEDIMENTATION AND BASIN-FILL HISTORY OF THE PLIOCENE SUCCESSION EXPOSED IN THE NORTHERN SIENA-RADICOFANI BASIN (TUSCANY, ITALY: A SEQUENCE-STRATIGRAPHIC APPROACH

    Directory of Open Access Journals (Sweden)

    IVAN MARTINI

    2017-08-01

    Full Text Available Basin-margin paralic deposits are sensitive indicators of relative sea-level changes and typically show complex stratigraphic architectures that only a facies-based sequence-stratigraphic approach, supported by detailed biostratigraphic data, can help unravel, thus providing constraints for the tectono-stratigraphic reconstructions of ancient basins. This paper presents a detailed facies analysis of Pliocene strata exposed in a marginal key-area of the northern Siena-Radicofani Basin (Tuscany, Italy, which is used as a ground for a new sequence-stratigraphic scheme of the studied area. The study reveals a more complex sedimentary history than that inferred from the recent geological maps produced as part of the Regional Cartographic Project (CARG, which are based on lithostratigraphic principles. Specifically, four sequences (S1 to S4, in upward stratigraphic order have been recognised, each bounded by erosional unconformities and deposited within the Zanclean-early Gelasian time span. Each sequence typically comprises fluvial to open marine facies, with deposits of different sequences that show striking lithological similarities.The architecture and internal variability shown by the studied depositional sequences are typical of low-accommodation basin-margin settings, that shows: i a poorly-developed to missing record of the falling-stage systems tract; ii a lowstand system tract predominantly made of fluvio-deltaic deposits; iii a highstand system tract with substantial thickness variation between different sequences due to erosional processes associated with the overlying unconformity; iv a highly variable transgressive system tract, ranging from elementary to parasequential organization.

  10. Past, present and future formation of groundwater resources in northern part of Baltic Artesian Basin

    Science.gov (United States)

    Marandi, A.; Vallner, L.; Vaikmae, R.; Raidla, V.

    2012-04-01

    Cambrian-Vendian Aquifer System (CVAS) is the deepest confined aquifer system used for water consumption in northern part of Baltic Artesian Basin (BAB). A regional groundwater flow and transport model (Visual Modflow) was used to investigate the paleohydrogeological scientific and contemporary management problems of CVAS. The model covers the territory of Estonia and its close surrounding, all together 88,000 km2 and includes all main aquifers and aquitards from ground surface to as low as the impermeable part of the crystalline basement. Three-dimensional distribution of groundwater heads, flow directions, velocities, and rates as well as transport and budget characteristics were simulated by the model. Water composition was changed significantly during the last glaciations.Strongly depleted O and H stable isotope composition, absence of 3H and low radiocarbon concentration are the main indicators of glacial origin of groundwater in the Cambrian-Vendian aquifer in northern Estonia. The noble gas analyses allowed concluding, that palaeorecharge took place at temperatures around the freezing point. While in North Estonia, most of water was changed by glacial melt water, high salinity water is till preserved in Southern part of Estonia.First results of modeling suggest that during the intrusion period lasting 7.3-9.3 ka the front of glacial thaw water movement had southeast direction and reachedto 180-220 kmfrom CVAS outcrop in Baltic Sea. Confining layer of CVAS is cut through by deep buried valleys in several places in North Estonia making possible for modern precipitation to infiltrate into aquifer system in present day. In case of natural conditions, the water pressure of CVAS is few meters above sea level and most of valleys act as discharge areas for aquifers system. Two regional depression ones have formed in North Estonia as a result of groundwater use from CVAS. Water consumption changes the natural groundwater gradient, flow direction and thereforerecharge

  11. Bottom currents and sediment waves on a shallow carbonate shelf, Northern Carnarvon Basin, Australia

    Science.gov (United States)

    Belde, Johannes; Reuning, Lars; Back, Stefan

    2017-04-01

    The modern seafloor of the Australian Northwest Shelf between Exmouth and Dampier was analyzed for large scale sedimentary bedforms on 3D seismic reflection data. The Carnarvon MegaSurvey of Petroleum Geo-Services (PGS), a merged dataset of multiple industrial 3D seismic reflection surveys with a total size of 49,717 km2, offers an extensive view of the continental shelf, slope and rise of the Northern Carnarvon Basin. Over the shelf two fields of large scale sediment waves were observed in water depths between 55-130 m, where the seafloor may be influenced by different processes including internal waves, tides and storms. Based on the dimensions and orientations of the sediment waves the dominant direction and approximate strength of local bottom currents could be estimated. Information on local sediment grain-size distribution was provided by the auSEABED database allowing a classification of the observed sediment waves into sand- or mudwaves. The first sediment wave field is positioned northwest of the Montebello Islands where the shelf is comparatively narrow and local sediment is mainly sand-sized. It most likely formed by increased bottom currents induced by the diversion of tidal flows around the islands. The second sediment wave field is located north of the Serrurier and Bessieres Islands within a local seafloor depression. Local sediments are poorly sorted, containing significant amounts of mud and gravel in addition to the mainly sand-sized grains. The coarser sediment fraction could have been reworked to sandwaves by cyclone-induced bottom currents. Alternatively, the finer sediment fraction could form mudwaves shaped by less energetic along-slope oriented currents in the topographic depression. The sediment waves consist partially of carbonate grains such as ooids and peloids that formed in shallow water during initial stages of the post glacial sea-level rise. These stranded carbonate grains thus formed in a different environment than the sediment

  12. Review of the Upper Jurassic-Lower Cretaceous stratigraphy in Western Cameros basin, Northern Spain

    DEFF Research Database (Denmark)

    Vidal, Maria del Pilar Clemente

    2010-01-01

    The Upper Jurassic-Lower Cretaceous stratigraphy of the Cameros basin has been reviewed. In Western Cameros the stratigraphic sections are condensed but they have a parallel development with the basin depocentre and the same groups have been identified. The Tera Group consists of two formations: ...

  13. Structure of the Wagner Basin in the Northern Gulf of California From Interpretation of Seismic Reflexion Data

    Science.gov (United States)

    Gonzalez, M.; Aguilar, C.; Martin, A.

    2007-05-01

    The northern Gulf of California straddles the transition in the style of deformation along the Pacific-North America plate boundary, from distributed deformation in the Upper Delfin and Wagner basins to localized dextral shear along the Cerro Prieto transform fault. Processing and interpretation of industry seismic data adquired by Petroleos Mexicanos (PEMEX) allow us to map the main fault structures and depocenters in the Wagner basin and to unravel the way strain is transferred northward into the Cerro Prieto fault system. Seismic data records from 0.5 to 5 TWTT. Data stacking and time-migration were performed using semblance coefficient method. Subsidence in the Wagner basin is controlled by two large N-S trending sub-parallel faults that intersect the NNW-trending Cerro Prieto transform fault. The Wagner fault bounds the eastern margin of the basin for more than 75 km. This fault dips ~50° to the west (up to 2 seconds) with distinctive reflectors displaced more than 1 km across the fault zone. The strata define a fanning pattern towards the Wagner fault. Northward the Wagner fault intersects the Cerro Prieto fault at 130° on map view and one depocenter of the Wagner basin bends to the NW adjacent to the Cerro Prieto fault zone. The eastern boundary of the modern depocenter is the Consag fault, which extends over 100 km in a N-S direction with an average dip of ~50° (up to 2s) to the east. The northern segment of the Consag fault bends 25° and intersects the Cerro Prieto fault zone at an angle of 110° on map view. The acoustic basement was not imaged in the northwest, but the stratigraphic succession increases its thickness towards the depocenter of the Wagner basin. Another important structure is El Chinero fault, which runs parallel to the Consag fault along 60 km and possibly intersects the Cerro Prieto fault to the north beneath the delta of the Colorado River. El Chinero fault dips at low-angle (~30°) to the east and has a vertical offset of about 0

  14. Fishing activity in Northern Rio de Janeiro State (Brazil and its relation with small cetaceans

    Directory of Open Access Journals (Sweden)

    Ana Paula Madeira Di Beneditto

    1998-01-01

    Full Text Available Research on fishing activity at Atafona village, in Northern Rio de Janeiro, Brazil (21°35'S, was carried out between 1987-96 for the purpose of relating it to the accidental capture of small cetaceans and of estimating the relationship between fishing activity and the diet of small cetaceans. Data on fishing operations were obtained at the cold storage plants management, from interviews with fishermen and personal observations. The most representative fishing resources were Xyphopenaeus kroyeri, Micropogonias furnieri, Carcharhinus plumbeus, C. acronotus,and Rhizoprionodon porosus. Gillnets are responsible for the accidental capture of small cetaceans in the region, mainly Pontoporia blainvillei and Sotalia fluviatilis (marine form. Four types of gillnets that are used on the region ("minjuada", "sarda", "caçoá" and "pescadinha" were dangerous to these species because they are placed in their preferred habitat. There is no competition between fishermen and small cetaceans due to the selection in the capture of commercialized fishesInvestigação sobre a atividade pesqueira na localidade de Atafona, Norte do Rio de Janeiro, Brasil (21º25`S, foi conduzida entre 1987-96 com o objetivo de relacioná-la com a captura acidental e a dieta dos pequenos cetáceos. Dados sobre as operações pesqueiras foram obtidos na administração dos entrepostos de pesca, através de entrevistas com pescadores e observações pessoais. Os recursos pesqueiros mais representativos foram Xyphopenaeus kroyeri, Micropogonias furnieri, Carcharhinus plumbeus, C. acronotus, and Rhizoprionodon porosus. As redes de espera são responsáveis pela captura acidental de pequenos cetáceos na região, principalmente de Pontoporia blainvillei e Sotalia fluviatilis (forma marinha. Quatro tipos de redes de espera que são usadas na região ("minjuada", "sarda", "caçoá" and "pescadinha" foram mais perigosas para essas espécies pois são colocadas no seu hábitat preferencial

  15. Physical activity and sedentary lifestyle among children from private and public schools in Northern Brazil.

    Science.gov (United States)

    Oliveira, Thiara Castro de; Silva, Antônio Augusto Moura da; Santos, Cristiane de Jesus Nunes dos; Silva, Josenilde Sousa e; Conceição, Sueli Ismael Oliveira da

    2010-12-01

    To analyze factors associated with physical activity and the mean time spent in some sedentary activities among school-aged children. A cross-sectional study was carried out in a random sample of 592 schoolchildren aged nine to 16 years in 2005, in São Luís, Northern Brazil. Data were collected by means of a 24-Hour Physical Activity Recall Questionnaire, concerning demographic and socioeconomic variables, physical activities practiced and time spent in certain sedentary activities. Physical activities were classified according to their metabolic equivalents (MET), and a physical activity index was estimated for each child. Sedentary lifestyle was estimated based on time spent watching television, playing videogames and on the computer/internet. Chi square test was used to compare proportions. Linear regression analysis was used to establish associations. Estimates were adjusted for the effect of the sampling design. The mean of the physical activity index was 605.73 MET-min/day (SD = 509.45). School children that were male (coefficient=134.57; 95%CI 50.77; 218.37), from public schools (coefficient.= 94.08; 95%CI 12.54; 175.62 and in the 5th to 7th grade (coefficient.=95.01; 95%CI 8.10;181.92 presented higher indices than females, children from private schools and in the 8th to the 9th grade (p<0.05). On average, students spent 2.66 hours/day in sedentary activities. Time spent in sedentary activities was significantly lower for children aged nine to 11 years (coefficient.= -0.49 hr/day; 95%CI -0.88; -0.10) and in lower socioeconomic classes (coefficient.=-0.87; 95%CI -1.45;-0.30). Domestic chores (59.43%) and walking to school (58.43%) were the most common physical activities. Being female, in private schools and in the 8th to 9th grade were factors associated with lower levels of physical activity. Younger schoolchildren and those from low economic classes spent less time engaged in sedentary activities.

  16. Metal and trace element sediment assessment from Guarapiranga reservoir, Alto Tiete Basin, Sao Paulo, SP, Brazil

    International Nuclear Information System (INIS)

    Guimaraes, Guilherme Moura

    2011-01-01

    The Guarapiranga Reservoir, located in Sao Paulo metropolitan region, Brazil, is responsible for supplying about 20% of the entire population's water needs of this region or approximately 3.7 million people. However, this system has shown significant degradation in water quality, due to untreated domestic sewage and industrial effluents. In this study sediment samples were collected at five points along the reservoir and total concentration of some major (Fe, K and Na), trace (As, Ba, Br, Co, Cr, Cs, Hf, Hg, Rb, Sb, Sc, Ta, Tb, Th, U, V and Zn) and rare earth (Ce, Eu, La, Lu, Nd, Sm, Tb and Yb) elements were determined by instrumental neutron activation analysis (INAA). By inductively coupled plasma optical emission spectrometry (ICP OES) the concentrations of Al, Ba, Be, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Ti, V e Zn were determined after digestion procedure following US EPA 3051 methodology. The concentrations of metals Cd and Pb were determined by graphite furnace atomic absorption spectrometry (GFAAS) and total Hg by cold vapor atomic absorption spectrometry (CVAAS). Methodology validation according to precision and accuracy was performed by reference materials analyses for the three different analytical techniques used. Multielemental results obtained by INAA were compared to NASC (North American Shale Composite), Upper Continental Crust (UCC) and soil from Guarapiranga park values. The Enrichment Factor (EF) and Geo accumulation Index (Igeo) were also evaluated for these data. Metal concentration results by ICP OES and AAS in the samples were compared to the TEL and PEL oriented values established by the Canadian Council of Ministers of the Environment and also adopted by CETESB (Environmental Protection Agency of the Sao Paulo State). The results were also compared to regional reference values (VRR) of limnic sediments from the Alto Tiete Basin. From these data an assessment of metal and trace element accumulated in the sediments from the

  17. Geophysical evidence of pre-sag rifting and post-rifting fault reactivation in the Parnaíba basin, Brazil

    OpenAIRE

    de Castro, David Lopes; Bezerra, Francisco Hilário; Fuck, Reinhardt Adolfo; Vidotti, Roberta Mary

    2016-01-01

    This study investigated the rifting mechanism that preceded the prolonged subsidence of the Paleozoic Parnaíba basin in Brazil and shed light on the tectonic evolution of this large cratonic basin in the South American platform. From the analysis of aeromagnetic, aerogravity, seismic reflection and borehole data, we concluded the following: (1) large pseudo-gravity and gravity lows mimic graben structures but are associated with linear supracrustal strips in the basement. (2...

  18. Saghro Group in the Ougnat Massif (Morocco), an evidence for a continuous Cadomian basin along the northern West African Craton

    Science.gov (United States)

    Michard, André; Soulaimani, Abderrahmane; Ouanaimi, Hassan; Raddi, Youssef; Aït Brahim, Lahsen; Rjimati, Ech-Cherki; Baidder, Lahssen; Saddiqi, Omar

    2017-03-01

    The Saghro Group (SG) is a folded, low-grade volcano-sedimentary series up to 8 km thick that crops out within and to the north of the Pan-African suture zone in the central and eastern Anti-Atlas. Here we describe the SG of the Ougnat inliers that are exposed in the easternmost Anti-Atlas beneath the unconformable, Late Ediacaran Ouarzazate Group (OZG) volcanic rocks. The Ougnat SG mostly consists of volcaniclastic greywackes accumulated in a peritidal-to-shallow basin. The basin infilling was deformed by NNE-trending, mostly upright folds with axial-planar slaty cleavage and low-grade metamorphism. The deformed SG rocks were intruded by the ∼550 Ma Mellab hypovolcanic granodiorite. The latter also crosscuts the lowest OZG rocks that are dated to 574-571 Ma in the western Saghro region. The SG rocks that form the Siroua and Saghro inliers have an oldest age of 620-610 Ma and were folded at ∼610-580 Ma at the onset of the Cadomian orogenic events. We show that the SG rocks are similar to the ;Série verte; (SV) rocks that are exposed in the Ougarta and western Hoggar east of the Pan-African suture. We infer that the SG and SV rocks accumulated in a same, continuous basin that was bounding the West African Craton to the north and the east. This strongly subsiding basin formed close to a volcanic arc and was folded during the last Pan-African synmetamorphic events. Fold orientation and age of folding differ however along the edge of the West African Craton. The orogenic greywackes that form the remnants of the SG-SV basin thus constitute a precious record of the diachronic Cadomian event s.l. along the West African Craton northern margin.

  19. Hydrological application of the INCA model with varying spatial resolution and nitrogen dynamics in a northern river basin

    Directory of Open Access Journals (Sweden)

    K. Rankinen

    2002-01-01

    Full Text Available As a first step in applying the Integrated Nitrogen model for CAtchments (INCA to the Simojoki river basin (3160 km2, this paper focuses on calibration of the hydrological part of the model and nitrogen (N dynamics in the river during the 1980s and 1990s. The model application utilised the GIS land-use and forest classification of Finland together with a recent forest inventory based on remote sensing. In the INCA model, the Hydrologically Effective Rainfall (HER is used to drive the water flow and N fluxes through the catchment system. HER was derived from the Watershed Simulation and Forecast System (WSFS. The basic component of the WSFS is a conceptual hydrological model which simulates runoff using precipitation, potential evapotranspiration and temperature data as inputs. Spatially uniform, lumped input data were calculated for the whole river basin and spatially semi-distributed input data were calculated for each of the nine sub-basins. When comparing discharges simulated by the INCA model with observed values, a better fit was obtained with the semi-distributed data than with the spatially uniform data (R2 0.78 v. 0.70 at Hosionkoski and 0.88 v. 0.78 at the river outlet. The timing of flow peaks was simulated rather well with both approaches, although the semi-distributed input data gave a more realistic simulation of low flow periods and the magnitude of spring flow peaks. The river basin has a relatively closed N cycle with low input and output fluxes of inorganic N. During 1982-2000, the average total N flux to the sea was 715 tonnes yr–1, of which 6% was NH4-N, 14% NO3-N, and 80% organic N. Annual variation in river flow and the concentrations of major N fractions in river water, and factors affecting this variation are discussed. Keywords: northern river basin, nitrogen, forest management, hydrology, dynamic modelling, semi-distributed modelling

  20. Gas hydrate formation and accumulation potential in the Qiangtang Basin, northern Tibet, China

    International Nuclear Information System (INIS)

    Fu, Xiugen; Wang, Jian; Tan, Fuwen; Feng, Xinglei; Wang, Dong; He, Jianglin

    2013-01-01

    Highlights: • Qiangtang Basin is the biggest residual petroleum-bearing basin in Tibet Plateau. • The Late Triassic Tumen Gela Formation is the most important gas source rock. • Seventy-one potential anticline structural traps have been found. • A favorable geothermal condition for gas hydrate formation. • A large number of mud volcanoes were discovered in the basin. - Abstract: The Qiangtang Basin is the biggest residual petroleum-bearing basin in the Qinghai–Tibet Plateau, and is also an area of continuous permafrost in southwest China with strong similarities to other known gas-hydrate-bearing regions. Permafrost thickness is typically 60–180 m; average surface temperature ranges from −0.2 to −4.0 °C, and the geothermal gradient is about 2.64 °C/100 m. In the basin, the Late Triassic Tumen Gela Formation is the most important gas source rock for gas, and there are 34.3 × 10 8 t of gas resources in the Tumen Gela Formation hydrocarbon system. Seventy-one potential anticline structural traps have been found nowadays covering an area of more than 30 km 2 for each individual one, five of them are connected with the gas source by faults. Recently, a large number of mud volcanoes were discovered in the central Qiangtang Basin, which could be indicative of the formation of potential gas hydrate. The North Qiangtang depression should be delineated as the main targets for the purpose of gas hydrate exploration

  1. Geographic, geologic, and hydrologic summaries of intermontane basins of the northern Rocky Mountains, Montana

    Science.gov (United States)

    Kendy, Eloise; Tresch, R.E.

    1996-01-01

    This report combines a literature review with new information to provide summaries of the geography, geology, and hydrology of each of 32 intermontane basins in western Montana. The summary of each intermontane basin includes concise descriptions of topography, areal extent, altitude, climate, 1990 population, land and water use, geology, surface water, aquifer hydraulic characteristics, ground-water flow, and ground-water quality. If present, geothermal features are described. Average annual and monthly temperature and precipitation are reported from one National Weather Service station in each basin. Streamflow data, including the drainage area, period of record, and average, minimum, and maximum historical streamflow, are reported for all active and discontinued USGS streamflow-gaging stations in each basin. Monitoring-well data, including the well depth, aquifer, period of record, and minimum and maximum historical water levels, are reported for all long-term USGS monitoring wells in each basin. Brief descriptions of geologic, geophysical, and potentiometric- surface maps available for each basin also are included. The summary for each basin also includes a bibliography of hydrogeologic literature. When used alone or in conjunction with regional RASA reports, this report provides a practical starting point for site-specific hydrogeologic investigations.

  2. Diet and potential feeding overlap between Trichiurus lepturus (Osteichthyes: Perciformes and Pontoporia blainvillei (Mammalia: Cetacea in Northern Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Vanessa T. Bittar

    2009-06-01

    Full Text Available This study describes the diet and assesses potential overlap in the feeding habits of Trichiurus lepturus Linnaeus, 1758 and Pontoporia blainvilleiGervais & D'Orbigny, 1844 in northern Rio de Janeiro, southeastern Brazil. Fishes were numerically dominant in both diets, followed by cephalopods for P. blainvillei and crustaceans for T. lepturus. Both predators move along similar coastal feeding areas in northern Rio de Janeiro, but our results indicate differences in their resource exploitation, what allows for their coexistence.

  3. Hydrogeology, groundwater levels, and generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system, 2010–14, in the northern Green River structural basin

    Science.gov (United States)

    Bartos, Timothy T.; Hallberg, Laura L.; Eddy-Miller, Cheryl

    2015-07-14

    In cooperation with the Bureau of Land Management, groundwater levels in wells located in the northern Green River Basin in Wyoming, an area of ongoing energy development, were measured by the U.S. Geological Survey from 2010 to 2014. The wells were completed in the uppermost aquifers of the Green River Basin lower Tertiary aquifer system, which is a complex regional aquifer system that provides water to most wells in the area. Except for near perennial streams, groundwater-level altitudes in most aquifers generally decreased with increasing depth, indicating a general downward potential for groundwater movement in the study area. Drilled depth of the wells was observed as a useful indicator of depth to groundwater such that deeper wells typically had a greater depth to groundwater. Comparison of a subset of wells included in this study that had historical groundwater levels that were measured during the 1960s and 1970s and again between 2012 and 2014 indicated that, overall, most of the wells showed a net decline in groundwater levels.

  4. Raft tectonics in northern Campos Basin; Tectonica de jangada (raft tectonics) na area norte da Bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Marilia R. de [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacases, RJ (Brazil)]|[PETROBRAS, Macae, RJ (Brazil). Unidade de Negocio da Bacia de Campos; Fugita, Adhemar M. [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Programa de Recursos Humanos da ANP

    2004-07-01

    In the northern area of Campos Basin salt gliding/spreading processes promoted the break-up and transport of Cretaceous and Tertiary rocks overlying the evaporites. This process is known as raft tectonics, and it represents the most extreme form of thin-skinned extension above the salt decollement surface. Three distinct geotectonic domains were recognized that formed in response to the raft tectonics. The first one, confined to the shallower shelf portion of the basin, is characterized by minor extension (pre-raft domain), probably because of small salt thickness and low gradient. In the second domain (or disorganized rafts domain), located in distal platformal and slope areas, seismic sections show the occurrence of blocks or rafts with angular shapes, sometimes imbricated and frequently discontinuous. In the third domain, or domain of organized rafts, located in bacinal region, seismic sections show a more continuous raft pattern, often folded because of salt compression in the distal portions of the basin. The main purposes of this work is to characterize these three tectonic domains distinguished by raft tectonics, as well as their importance in hydrocarbon accumulations in calcarenites. (author)

  5. Geologic implications of large-scale trends in well-log response, northern Green River Basin, Wyoming

    International Nuclear Information System (INIS)

    Prensky, S.E.

    1986-01-01

    Well-log response in lower Tertiary and Upper Cretaceous rocks in the northern Green River basin, Wyoming, is examined. Digitally recorded well-log data for selected wells located throughout the basin were processed by computer and displayed as highly compressed depth-scale plots for examining large-scale geologic trends. Stratigraphic units, formed under similar depositional conditions, are distinguishable by differing patterns on these plots. In particular, a strong lithologic contrast between Tertiary and underlying Upper Cretaceous non-marine clastic rocks is revealed and correlated through the study area. Laboratory analysis combined with gamma-ray spectrometry log data show that potassium feldspars in the arkosic Tertiary sandstones cause the contrast. The nature and extent of overpressuring has been examined. Data shift on shale conductivity and shale acoustic transit-time plots, previously ascribed to changes in pore pressure, correspond to stratigraphic changes and not necessarily with changes in pore pressure as indicated by drilling-mud weights. Gulf Coast well-log techniques for detecting overpressuring are unreliable and ineffectual in this basin, which has experienced significantly different geologic depositional and tectonic conditions

  6. Hydrological Responses to Changes in the Rainfall Regime are Less Pronounced in Forested Basins: an Analysis of Southern Brazil, 1975-2010

    Science.gov (United States)

    Chagas, V. B. P.; Chaffe, P. L. B.

    2017-12-01

    It is unknown to what extent the hydrological responses to changes in the rainfall regime vary across forested and non-forested landscapes. Southern Brazil is approximately 570000 km² and was naturally covered mostly by tropical and subtropical forests. In the last century, a large proportion of forests were replaced by agricultural activities. The rainfall regime has also changed substantially in the last decades. The annual rainfall, number and magnitude of extreme events, and number of non-rainy days have increased in most of the area. In this study, we investigated the changes in the regime of 142 streamflow gauges and 674 rainfall gauges in Southern Brazil, from 1975 to 2010. The changes in the regime were analyzed for forested basins (i.e., with more than 50% forest coverage) and non-forested basins (i.e., with less than 20% forest coverage). The area of the river basins ranged from 100 to 60000 km². We analyzed a total of six signatures that represent the regime, including annual averages, seasonality, floods, and droughts. The statistical trends of the signatures were calculated using the Mann-Kendall test and the Sen's slope. The results showed that the majority of basins with opposing signal trends for mean annual streamflow and rainfall are non-forested basins (i.e., basins with higher anthropogenic impacts). Forested basins had a lower correlation between trends in the streamflow and rainfall trends for the seasonality and the average duration of drought events. There was a lower variability in the annual maximum 1-day streamflow trends in the forested basins. Additionally, despite a decrease in the 31-day rainfall minima and an increase in the seasonality, in forested basins the 7-day streamflow minima increases were substantially larger than in non-forested basins. In summary, the forested basins were less responsive to the changes in the precipitation 1-day maxima, seasonality, number of dry days, and 31-day minima.

  7. Genetic structure of lake whitefish, Coregonus clupeaformis, populations in the northern main basin of Lake Huron

    Science.gov (United States)

    Stott, Wendylee; Ebener, Mark P.; Mohr, Lloyd; Schaeffer, Jeff; Roseman, Edward F.; Harford, William J.; Johnson, James E.; Fietsch, Cherie-Lee

    2012-01-01

    Genetic analysis of spawning lake whitefish (Coregonus clupeaformis) from six sites in the main basin of Lake Huron was conducted to determine population structure. Samples from fisheryindependent assessment surveys in the northwest main basin were analyzed to determine the relative contributions of lake whitefish genetic populations. Genetic population structure was identified using data from seven microsatellite DNA loci. One population was identified at Manitoulin Island, one to two were observed in the east-central main basin (Fishing Island and Douglas Point), and one to two populations were found in the northwest (Thunder Bay and Duncan Bay). The genetic identity of collections from Duncan Bay and Thunder Bay was not consistent among methods used to analyze population structure. Low genetic distances suggested that they comprised one population, but genic differences indicated that they may constitute separate populations. Simulated data indicated that the genetic origins of samples from a mixed-fishery could be accurately identified, but accuracy could be improved by incorporating additional microsatellite loci. Mixture analysis and individual assignment tests performed on mixed-stock samples collected from the western main basin suggested that genetic populations from the east-central main basin contributed less than those from the western main basin and that the proportional contribution of each baseline population was similar in each assessment sample. Analysis of additional microsatellite DNA loci may be useful to help improve the precision of the estimates, thus increasing our ability to manage and protect this valuable resource.

  8. Using SIMGRO for drought analysis – as demonstrated for the Taquari Basin, Brazil

    NARCIS (Netherlands)

    Querner, E.P.; Lanen, van H.A.J.

    2010-01-01

    Tools were developed and tested to quantify space–time development of droughts at the river basin scale. The spatial development of a hydrological drought in river basins brings different challenges to describe drought characteristics, such as: area in a drought and areal expressions for onset,

  9. Magnetotelluric and aeromagnetic investigations for assessment of groundwater resources in Parnaiba basin in Piaui State of North-East Brazil

    Science.gov (United States)

    Chandrasekhar, E.; Fontes, Sergio L.; Flexor, Jean M.; Rajaram, Mita; Anand, S. P.

    2009-06-01

    In an attempt to locate the presence of possible groundwater resource regions in the semi-arid North-East Brazil, an integrated survey including aeromagnetic and magnetotelluric (MT) studies have been undertaken in the Guaribas region and only MT survey in the Caracol region. In the Guaribas region the aeromagnetic data, its analytic signal and Euler solutions reveal several subsurface small-scale faults and intrusives that are conducive to be potential groundwater resource regions. A total of about 22 broad-band magnetotelluric (MT) soundings in the period range of 0.006-300 s along two profiles on the marginal arcs of the intra-cratonic sedimentary Parnaíba basin in North-East Brazil have been made across the regional geological strike, the Senador Pompeu Lineament (SPL). SPL trends N40°E and marks a basement high reflecting an irregularity in the original basin geometry. While one of the MT profiles traverses across the SPL, the other lies only in the aeromagnetically surveyed sedimentary region. Two-dimensional inversion of MT data of both profiles shows that the sedimentary basin is conductive (100-150 Ω m) and shows as a thin graben with an average thickness of about 2-3 km beneath both profiles. The basin is located to be at shallow depths (from surface to about 500 m). Based on the facts that the study region falls on sedimentary region having low-to-very low permeability and also in accordance with the subsurface lithology around the study region, the mapped sedimentary basin largely manifests the zone of potential sedimentary aquifer having moderate resistivity of 50-250 Ω m and is located at relatively shallow depths. The identified aquifer zone is believed to have links with the Parnaiba River flowing at a distance of about 300 km NW from the study region. We discuss interpretation of our results of MT and aeromagnetic data sets in the light of hydrological features of the study region.

  10. Late-Miocene thrust fault-related folding in the northern Tibetan Plateau: Insight from paleomagnetic and structural analyses of the Kumkol basin

    Science.gov (United States)

    Lu, Haijian; Fu, Bihong; Shi, Pilong; Xue, Guoliang; Li, Haibing

    2018-05-01

    Constraints on the timing and style of the Tibetan Plateau growth help spur new understanding of the tectonic evolution of the northern Tibetan Plateau and its relation to the India-Asia continental collision. In this regard, records of tectonic deformation with accurate ages are urgently needed, especially in regions without relevant studies. The Kumkol basin, located between two major intermontane basins (the Hoh Xil and Qaidam basins), may hold clues to how these major basins evolve during the Cenozoic. However, little has been known about the exact ages of the strata and tectonic deformation of the basin. Herein, detailed paleomagnetic and structural studies are conducted on the southern Baiquanhe section in the central Kumkol basin, northern Tibetan Plateau. The magnetostratigraphic study indicates that the southern Baiquanhe section spans a time interval of 8.2-4.2 Ma. Well-preserved growth strata date to 7.5 Ma, providing evidence for a significant thrust fault-related folding. This thrust-related folding has also been identified in the Tian Shan foreland and in the northern Tibetan Plateau, most likely implying a pulsed basinward deformation during the late Miocene.

  11. Structural and geological analysis of the northern Pescadero basin: preliminary results based on the analysis of 2D multichannel seismic reflection profiles

    Science.gov (United States)

    Spelz, R. M.; Ramirez-Zerpa, N. A.; Gonzalez-Fernandez, A.; Yarbuh, I.; Contreras, J.

    2017-12-01

    The Pacific-North America plate boundary along the Gulf of California is characterized by an array of right-stepping, right-lateral, transform faults connecting a series of pull-apart basins distributed along the gulf axis. Altogether, these structures accommodate an oblique-divergent component of deformation characterizing the modern tectonic regime along the gulf. The northern Pescadero complex, in the southern Gulf of California, is one of the deepest and probably least studied transtensional fault-termination basins in the gulf. The complex is bounded to the north and south by Atl and Farallon transform faults, respectively, and consists of two asymmetric, rhomboidal-shaped, basins with a series of intrabasinal high-angle normal faults and ramps connecting their depocenters. In this study we present preliminary results derived from the processing and analysis of 400 km of seismic reflection profiles, collected in 2006 onboard the R/V Francisco de Ulloa in northern Pescadero, providing new insights into the geology and internal structure of the basin. Northern Pescadero is a deep and narrow basin characterized by a maximum sedimentary infill of 1 km, and depths to the basin floor exceeding 3500 m. Deformation is chiefly accommodated by an array of self-parallel half-graben structures that appear to grow towards the northern flank of the basin. Faults-scarps located farther from the deformation axis appear to be more degraded, suggesting a progressively younger age of the half-grabens near the basin's depocenter. Another important feature revealed in the seismic images is the lack of sediments on top of the crystalline basement that floors the narrow central portion of the basin. In this area the reflectors at the basin's floor show a pronounced increase in amplitude and coherence, indicating the emplacement of magmatic extrusions. Likewise, in those areas with the greater sediment infill, the occurrence of high-amplitude reflectors, located 150 m below the

  12. Biological and genetic characterization of Cryptosporidium spp. and Giardia duodenalis isolates from five hydrographical basins in northern Portugal.

    Science.gov (United States)

    Almeida, André; Moreira, Maria João; Soares, Sónia; de Lurdes Delgado, Maria; Figueiredo, João; Magalhães, Elisabete Silva; Castro, António; Viana Da Costa, Alexandra; Correia da Costa, José Manuel

    2010-06-01

    To understand the situation of water contamination with Cryptosporidium spp. and Giardia spp. in the northern region of Portugal, we have established a long-term program aimed at pinpointing the sources of surface water and environmental contamination, working with the water-supply industry. Here, we describe the results obtained with raw water samples collected in rivers of the 5 hydrographical basins. A total of 283 samples were analyzed using the Method 1623 EPA, USA. Genetic characterization was performed by PCR and sequencing of genes 18S rRNA of Cryptosporidium spp. and beta-giardin of Giardia spp. Infectious stages of the protozoa were detected in 72.8% (206 of 283) of the water samples, with 15.2% (43 of 283) positive for Giardia duodenalis cysts, 9.5% (27 of 283) positive for Cryptosporidium spp. oocysts, and 48.1% (136 of 283) samples positive for both parasites. The most common zoonotic species found were G. duodenalis assemblages A-I, A-II, B, and E genotypes, and Cryptosporidium parvum, Cryptosporidium andersoni, Cryptosporidium hominis, and Cryptosporidium muris. These results suggest that cryptosporidiosis and giardiasis are important public health issues in northern Portugal. To the authors' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in raw water samples in the northern region of Portugal.

  13. Sedimentologic and paleoclimatic reconstructions of carbonate factory evolution in the Alborz Basin (northern Iran) indicate a global response to Early Carboniferous (Tournaisian) glaciations

    Science.gov (United States)

    Sardar Abadi, Mehrdad; Kulagina, Elena I.; Voeten, Dennis F. A. E.; Boulvain, Frédéric; Da Silva, Anne-Christine

    2017-03-01

    The Lower Carboniferous Mobarak Formation records the development of a storm-sensitive pervasive carbonate factory on the southern Paleo-Tethyan passive margin following the opening of the Paleo-Tethys Ocean into the Alborz Basin along the northern margin of Gondwana. Its depositional facies encompass inner ramp peritidal environments, peloidal to crinoidal shoals, storm to fair-weather influenced mid-ramps, proximal to distal shell beds and low energy outer ramps. Sedimentological analyses and foraminiferal biostratigraphy reveal four events affecting carbonate platform evolution in the Alborz Basin during the Lower Carboniferous: (1) A transgression following global temperature rise in the Early Tournaisian (middle Hastarian) caused the formation of thick-bedded argillaceous limestones. This interval correlates with Early Tournaisian nodular to argillaceous limestones in the Moravia Basin (Lisen Formation, Czech Republic), the Dinant Basin (Pont d'Arcole Formation, Belgium), and at the Rhenish Slate Mountains (Lower Alum shale, Germany). (2) Late Hastarian-early Ivorian glaciations previously identified in Southern Gondwana but had not yet recognized in Northern Gondwana were recorded through a sequence boundary. (3) During the Late Tournaisian-Early Visean?, a differential block faulting regime along the basin's margin caused uplift of the westernmost parts of the Alborz Basin and resulted in subsidence in the eastern part of the central basin. This tectonically controlled shift in depositional regime caused vast sub-aerial exposure and brecciation preserved in the top of the Mobarak Formation in the western portion of the Central Alborz Basin. (4) Tectonic activity coinciding with a progressive, multiphase sea level drop caused indirectly by the Viséan and Serpukhovian glaciations phases ultimately led to the stagnation of the carbonate factory. Paleothermometry proxies, the presence of foraminiferal taxa with a northern Paleo-Tethyan affinity and evidence for

  14. Crop water parameters of irrigated wine and table grapes to support water productivity analysis in the Sao Francisco river basin, Brazil

    NARCIS (Netherlands)

    Castro Teixeira, de A.H.; Bastiaanssen, W.G.M.; Bassoi, L.H.

    2007-01-01

    Energy and water balance parameters were measured in two commercial vineyards in the semiarid region of the São Francisco river basin, Brazil. Actual evapotranspiration (ET) was acquired with the Bowen ratio surface energy balance method. The ratio of the latent heat flux to the available energy, or

  15. Effects of plant cover on the macrofauna of Spartina marshes in northern Brazil

    Directory of Open Access Journals (Sweden)

    Cesar França Braga

    2009-12-01

    Full Text Available Data on macrofauna density and diversity, and the height and density of Spartina brasiliensis, were obtained from salt marsh beds of a tropical estuary in northern Brazil. Sampling was carried out at four distinct times of the year, during the wet and dry seasons and in the transition periods between these. Sampling was also carried out in salt marshes of three size classes, small, medium and large. Variables were analyzed in relation to time of year and salt marsh size class. Overall, 46 taxa were found, with polychaetes, isopods and the gastropod Neritina virginea dominating the fauna. Macrofauna density and diversity were positively correlated with culm density, indicating a possible role in protection from predation. All the three variables were higher during the transitional periods between the wet and dry seasons and seasonal changes in rainfall, salinity and light availability may influence mortality, food availability and settlement of the macrofauna. There was no effect of salt marsh size on either the macrofauna or the vegetation.Dados sobre a densidade e diversidade da macrofauna em relação à altura e densidade de Spartina brasiliensis foram obtidos em bancos de marismas em um estuário tropical no norte do Brasil. A amostragem foi realizada quatro vezes durante um ano, nas estações chuvosa, seca e nos períodos de transição entre estas. A amostragem foi realizada em marismas de três classes de tamanho: pequeno, médio e grande. As variáveis foram analisadas em relação às estações do ano e das classes de tamanho das marismas. Um total de 46 táxons foram encontrados, com os poliquetos, isopodos e o gastropódo Neritina virginea dominando a fauna, resultados similares a estudos realizados em marismas no sul do Brasil. A densidade e a diversidade da macrofauna foram correlacionadas positivamente com a densidade de colmos da vegetação, indicando um possível papel da vegetação em proteção contra predação. Todas as

  16. Capture fishery in northern Todos os Santos Bay, tropical southwestern Atlantic, Brazil

    Directory of Open Access Journals (Sweden)

    Lucy Satiko Hashimoto Soares

    2011-03-01

    Full Text Available Information on marine and estuarine capture fishery activity in northern Todos os Santos Bay, northeastern Brazil, based on daily data collected between September 2003 and June 2005 is presented. Small-scale artisanal fishery in this area includes the use of traditional vessels both nonmotorized and motorized for locomotion, being carried out mainly by canoe or on foot, and involves many different kinds of gear, including gillnet, hook and line, seine nets, and traps. A total of 113 taxa were grouped into 77 resources, including 88 fish, 10 crustaceans, and 15 mollusks. Data on nominal catches of fish, crustaceans and mollusks are presented by month and location. A total of 345.2 tonnes of fishery resources were produced (285.4 tonnes of fish, 39.2 tonnes of fresh invertebrates, and 20.6 tonnes of processed invertebrates. Temporal variation in the fish catch was associated with the life cycle of the species or with the hydrographic conditions. The first-sale value of this catch amounted to around US$ 615,000.00, fishes representing 71.3% of it. A table of the average price of each fishery resource is presented. The results produced in this study may be considered a reference for future monitoring programs of fishery resources in the area.Informações sobre a atividade pesqueira extrativa da região norte da Baía de Todos os Santos, Bahia, nordeste do Brasil são apresentadas, baseadas em coleta diária de dados, realizada entre setembro de 2003 e junho de 2005. Trata-se de uma atividade extrativa artesanal, na qual são utilizadas embarcações tradicionais para o deslocamento ao local da extração. Em cada pescaria foram utilizadas várias artes, tais como rede de espera, linha e anzol, rede de cerco, armadilhas. Foram identificadas 113 categorias taxonômicas de peixes (88, crustáceos (10 e moluscos (15, arranjadas em 77 tipos de pescados comercializados. A produção total no período foi de 345,2 t (285.4 t de peixes, 39,2 t de

  17. Provenance of Miocene Hinterland Basins in Ecuador: Implications for the Growth of Topographic Barriers in the Northern Andes

    Science.gov (United States)

    George, S. W. M.; Horton, B. K.; Vallejo, C.; Nogales, V.

    2017-12-01

    Establishment of the Eastern Cordillera of Ecuador as an Andean topographic barrier caused significant drainage reorganization, perhaps even as dramatic as the reversal of the Amazon River. Cenozoic growth of this barrier coincided with substantial increases in speciation rates in Andean and Amazonian environments. Situated in the Interandean Depression between the Eastern Cordillera and Western Cordillera of Ecuador, a series of well-preserved Miocene intermontane basins offer a unique opportunity to constrain the along-strike development of the flanking north-trending cordilleras as drainage divides in the Northern Andes. Here were provide detrital zircon U-Pb geochronological results for 17 samples from Ecuadorian hinterland basins (Cuenca, Giron-Santa Isabel, Nabón, Loja, and Vilcabamba), supplemented with measured sections in the Cuenca Basin, to provide insights on orogenic development of the cordilleras of Ecuador during the Miocene. In addition, we characterize the age distributions of basement units to more precisely determine sediment routing patterns through time. Detrital zircon geochronological data yields regional upsection trends throughout Miocene stratigraphic sections marked by: (1) middle Miocene deposits containing a strong syndepositional age peak, with a complementary Eocene-Oligocene peak in varying abundances, and subsidiary low-intensity Paleozoic-Proterozoic age peaks; and (2a) upper Miocene deposits maintaining similar trends to that of the middle Miocene, or (2b) upper Miocene deposits showing a dramatic shutoff of most Cenozoic populations and a switch to Paleozoic-Proterozoic sources, as seen in the Nabón and Loja basins. Syndepositional signatures reflect derivation from the magmatic arc, while varying inputs of Eocene-Oligocene zircons were derived from the Eocene-Oligocene volcanic rocks that comprise the effective basement of much of the Interandean Depression. The late Miocene shift to Paleozoic-Proterozoic sources observed in

  18. Paleoenvironmental changes and influence on Operculodinium centrocarpum during the Quaternary in the Campos Basin, southwestern Brazil

    Science.gov (United States)

    Santos, Alessandra; de Araujo Carvalho, Marcelo; de Oliveira, Antônio Donizeti; Mendonça Filho, João Graciano

    2017-12-01

    The purpose of this paper is to document the changes observed in the Quaternary dinoflagellate assemblages from 80 core samples from the Campos Basin. The Interglacial (Subzone X1), Glacial (Subzones Y5 to Y2), Last Glacial Maximum (Subzone Y1) and Post-Glacial (Zone Z) intervals were identified. High abundance of Operculodinium centrocarpum suggests the warm, high salinity and nutrient-poor water conditions dominated the upper water column of the Campos Basin. The climate and oceanic current dynamic of the continental slope of the Campos Basin appears to has been a significant controlling factor in the distribution of dinocysts, particularly of O. centrocarpum, during the Pleistocene/Holocene transition.

  19. A new species of Microglanis (Siluriformes: Pseudopimelodidae from upper rio Paraná basin, Brazil

    Directory of Open Access Journals (Sweden)

    Oscar Akio Shibatta

    Full Text Available Microglanis garavelloi, new species, collected in tributaries of rio Paranapanema and rio Tietê, is the first species of the genus described from upper rio Paraná basin. The new species can be distinguished from other species of Microglanis on morphometric characters, color pattern, caudal-fin shape, pectoral-spine morphology and lateral line development. Characters used specifically to distinguish M. garavelloi from M. cottoides (laguna dos Patos and rio Uruguay basins and M. parahybae (rio Paraíba do Sul basin include morphometrics, color pattern and pectoral-spine serration.

  20. Mercury in sediments from shelf and continental slope at Campos Basin near Rio de Janeiro, Brazil

    Science.gov (United States)

    Araujo, Beatriz; Hintelmann, Holger; Dimock, Brian; Gomes de Almeida, Marcelo; Falcão, Ana Paula; de Rezende, Carlos Eduardo

    2016-04-01

    Mercury (Hg) is a global pollutant due to its ability to undergo long-range transport from source regions to remote parts of the world, and its ubiquitous presence in aquatic ecosystems. The Hg isotope ratios could be an effective tool for tracing the sources and process of Hg in the environment. This study aimed to establish the distribution of mercury in surface sediments of three transects (25- 3000m water depth) in continental shelf and slope in Campos Basin-RJ-Brazil, using the Hg isotopes to understand the geochemical processes relating to Hg cycling that occur in a subtropical coastal environment. The study area was divided into three transects: A (located to the south and close to a upwelling area), D (located opposite the mouth of the Paraiba do Sul River) and I (located north near the top of Vitória-ES). Sampling isobaths were 25, 50, 75, 100, 150, 400, 700, 1000, 1300, 1900, 2500 and 3000m. The Total Hg, MMHg and Hg stable isotopes were determined based on EPA Method 1631, EPA method 1630 and Foucher and Hintelmann (2006), respectively. The silt/clay ranged from 0.05 to 95%, and the organic carbon (OC) from 0.07 to 1.43 % for all transects. THg and MMHg concentrations in the shelf were 11.9 ± 7.2 (1.7- 22.2) ng.g-1 and 0.15 ± 0.12 (0.02 - 0.40) ng.g-1; in the slope 30.3 ± 9.2 (11.6 - 51.6) ng.g-1 and 0.13 ± 0.06 (0.03 -0.29) ng.g-1 , respectively. The δ202Hg and Δ199Hg varied from -0.32 to -1.85 ‰ (-0.79 ± 0.44‰) and -0.41 to 0.09 ‰ (-0.03 ± 0.12 ‰) for all transects, respectively. The delta values between both regions are significantly different, the shelf region showed δ202Hg from -0.59 to -2.19 ‰ (mean: -1.52 ±0.65) and Δ199Hg from - 0.53 to 0.08 ‰ (mean: -0.27 ±0.55) and the slope region were observed δ202Hg values from -0.32 to -1.82 ‰ (mean: -0.73 ±0.39 ‰ n=18) and gΔ199Hg from -0.23 to 0.09‰ (mean: -0.02 ±0.08‰ n=5). The slope appears to be enriched with heavier isotopes compared to the shelf, however, in the

  1. Geomorphological and morphometric analysis of the river basin of Salsa, south coast of the state of Paraiba / Brazil

    International Nuclear Information System (INIS)

    Barbosa, M.E.; Nascimento, J.; Furrier, M.

    2010-01-01

    This paper aims to extend the knowledge on the geomorphology of the river basin of Salsa , located in the municipality of Conde, State of Paraíba / Brazil . The research was to develop guiding object thematic maps related to morphometric aspects of the basin such as fluvial hierarchy , hypsometric and slope . After obtaining the morphometric data can assess the likely tectonic influences on the morphology of this basin. Literature searches , acquisition and analysis of cartographic data (satellite imagery , topographic and thematic maps), where with the help of software SPRING 5:03 , were made the thematic maps of the basin : For this research, the following milestones have been met. In addition, there have been two topographic profiles of the area through which it was possible to further analyze the geomorphological aspects and clinográficos watershed. Already in possession of the first results of this research it was observed with the analysis of charts and topographic profiles the high level of dissection Barriers Training and dissection of this discrepancy between the left and right margins . Barriers in Education, was observed indicative of tectonics from setbacks headwater quite different slots and obsequente towards the River Salsa (SN), which is discordant from the direction of the main waterways and Training Barriers own inclination is that WE . These findings are important because the geomorphological analysis of litoestatigráfica unit is of paramount importance for the understanding of the mechanisms governing the morphology of the northeast coast, mainly in relation to the mechanisms that govern the morphology of watersheds coast of Paraiba

  2. Geochemical behavior of radionuclides and heavy metals in soils from Corumbatai River basin (SP), Brazil

    International Nuclear Information System (INIS)

    Conceicao, Fabiano Tomazini da

    2004-01-01

    The purpose of this research was to study the geochemical behavior of radionuclides and heavy metals in soils of agricultural use at Corumbatai River basin (SP). The natural concentration and variability in sedimentary rocks at Corumbatai river basin follow the trend Ca > Mg > K > Na, with the concentration of heavy metals and radionuclides. The distribution of exposure rate in soils shows the occurrence of higher values towards south of the Corumbatai river basin, region where are applied phosphate fertilizers, amendments and 'vinhaca' in sugar cane crops. Heavy metals and radionuclides incorporated in phosphate fertilizers and amendments are annually added during the fertilization process in the sugar cane crops, but if they are utilized in accordance with the recommended rate, they do not rise the concentration levels in soils up to hazards levels. Thus, they are lower transferred from soils to sugar cane at Corumbatai river basin, not offering hazard to the ecosystem and animal or human health. (author)

  3. An integrated geological and geophysical study of the Parnaíba cratonic basin, North-East Brazil

    Science.gov (United States)

    Tozer, B.; Watts, A. B.; Daly, M.

    2015-12-01

    Cratonic basins are characterized by their sub-circular shape, long-lived (>100 Myr) subsidence, shallow marine/terrestrial sediments that young towards the center of the basin and exhibit little internal deformation, and thick seismic lithosphere. Despite the recognition of >30 world-wide, the paucity of geological and geophysical data over these basins means their origin remains enigmatic. In order to address this problem, we have used a recently acquired 1400 km long seismic reflection profile recorded to 20 s TWTT, field observations and well logs, gravity and magnetic data acquired at 1 km intervals, and five wide-angle refection/refraction receiver gathers recorded at offsets up to 100 km, to constrain the origin of the Parnaíba basin, North-East Brazil. We find a depth to pre-Paleozoic basement and Moho of ~ 3.5 and ~ 40 - 42 km respectively beneath the basin center. A prominent mid-crustal reflection (MCR) can be tracked laterally for ~ 300 km at depths between 17 - 25 km and a low-fold wide-angle receiver gather stack shows that the crust below the MCR is characterized by a ~ 4 s TWTT package of anastomosing reflections. Gravity modelling suggests that the MCR represents the upper surface of a high density (+0.14 kg m-3) lower crustal body, which is probably of magmatic origin. Backstripping of biostratigraphic data from wells in the center of the basin show an exponentially decreasing subsidence. We show that although cooling of a thick (180 km) lithosphere following prolonged rifting (~ 65 Myr) can provide a good fit to the tectonic subsidence curves, process-oriented gravity and flexure modelling suggest that other processes must be important, as rifting does not account for the observed gravity anomaly and predicts too thin a crust (~ 34 km). The thicker than expected crust suggests warping due, for example, to far-field stresses or basal tractions. Another possibility, which is compatible with existing geophysical data, is a dense magmatic intrusion

  4. Drought propagation in the Paraná Basin, Brazil: from rainfall deficits to impacts on reservoir storage

    Science.gov (United States)

    Melo, D. D.; Wendland, E.

    2017-12-01

    The sensibility and resilience of hydrologic systems to climate changes are crucial for estimating potential impacts of droughts, responsible for major economic and human losses globally. Understanding how droughts propagate is a key element to develop a predictive understanding for future management and mitigation strategies. In this context, this study investigated the drought propagation in the Paraná Basin (PB), Southeast Brazil, a major hydroelectricity producing region with 32 % (60 million people) of the country's population. Reservoir storage (RESS), river discharge (Q) and rainfall (P) data were used to assess the linkages between meteorological and hydrological droughts, characterized by the Standard Precipitation Index (SPI) and Streamflow Drought Index (SDI), respectively. The data are from 37 sub-basins within the PB, consisting of contributing areas of 37 reservoirs (250 km3 of stored water) within the PB for the period between 1995 and 2015. The response time (RT) of the hydrologic system to droughts, given as the time lag between P, Q and RESS, was quantified using a non-parametric statistical method that combines cumulative sums and Bootstrap resampling technique. Based on our results, the RTs of the hydrologic system of the PB varies from 0 to 6 months, depending on a number of aspects: lithology, topography, dam operation, etc. Linkages between SPI and SDI indicated that the anthropogenic control (dam operation) plays an important role in buffering drought impacts to downstream sub-basins: SDI decreased from upstream to downstream despite similar SPI values over the whole area. Comparisons between sub-basins, with variable drainage sizes (5,000 - 50,000 km2), confirmed the benefice of upstream reservoirs in reducing hydrological droughts. For example, the RT for a 4,800 km2 basin was 6 months between P and Q and 9 months between Q and RESS, under anthropogenic control. Conversely, the RT to precipitation for a reservoir subjected to natural

  5. Integrated modeling of water quantity and quality in the Araguari River basin, Brazil

    OpenAIRE

    Salla, Marcio Ricardo; Paredes-Arquiola, Javier; Solera, Abel; Álvarez, Joaquín Andreu; Pereira, Carlos Eugênio; Alamy Filho, José Eduardo; De Oliveira, André Luiz

    2014-01-01

    The Araguari River basin has a huge water resource potential. However, population and industrial growth have generated numerous private and collective conflicts of interest in the multiple uses of water, resulting in the need for integrated management of water quantity and quality at the basin scale. This study used the AQUATOOL Decision Support System. The water balance performed by the SIMGES module for the period of October 2006 to September 2011 provided a good representation of the reali...

  6. Contribution of the institutions in the Northern region of Brazil to the development of plant cultivars and their impact on agriculture

    Directory of Open Access Journals (Sweden)

    Aparecida das Graças Claret de Souza

    2012-12-01

    Full Text Available This paper describes the development of breeding programs in northern Brazil and their main impacts on agriculture. Their contribution to the breeding of the species palm oil, acai fruit, cacao, cupuaçu, guarana, tomato, camu-camu, cocona, peach palm, and rubber was laid out in detail. Advances in breeding programs of institutions such as Embrapa, Ceplac, Inpa, and Universities require investments in infrastructure and in human and financial resources to ensure continuity and efficiency in economic, social and environmental gains. The improvement of native species, the main focus of the breeding programs of the institutions in the Northern region of Brazil, is a form of exploiting the Amazonian biodiversity for the benefit of society. Therefore, policies to foster research institutions should be a subject of deliberation and action of the scientific and technological community in Brazil.

  7. Tectonic-stratigraphic evolution of Cumuruxatiba Basin - Brazil; Evolucao tectono-estratigrafica da Bacia de Cumuruxatiba

    Energy Technology Data Exchange (ETDEWEB)

    Lobato, Gustavo; Fernandes, Flavio L.; Silva, Eric Zagotto; Ferreira Neto, Walter Dias [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Modelagem Multidisciplinar de Bacias Sedimentares; Ribeiro, Juliana [Agencia Nacional do Petroleo, Gas Natural e Biocombustiveis (ANP), Brasilia, DF (Brazil)

    2008-07-01

    In recent years, the exploratory interest on Cumuruxatiba Basin has been inconstant, with modest discoveries of oil. Aiming to deepen the geological knowledge of the basin and in order to attract the interest of oil companies, the ANP (National Agency of Petroleum, Natural Gas and Biofuels) signed contract with COPPE/UFRJ for carrying out an analysis basin project. The project was developed by the Basin Analysis Multidisciplinary Modeling Laboratory (Lab2M/UFRJ) in the period 2006/2007, and was with the main objective outline the main structural and seismo-stratigraphic features of the basin, and in an integrated and multidisciplinary way, build a model of its sedimentation and tectono-stratigraphic evolution. This paper presents the results of the regional seismic mapping, aided by well and potential methods data. The stratigraphic succession the basin has been divided into genetic units (UN-B, UN-C e UN-D) corresponding to second order depositional sequences, they are: UN-B, corresponding by a rift and sag-rift siliciclastic deposits, plus the Aptian evaporitic deposits; UN-C, characterized by carbonatic deposits, and shelf related sediments; and UN-D, corresponding by a final transgressive (siliciclastic) - regressive (mix) cycle, between Cenomanian and actual days. (author)

  8. Stratigraphy of the Roraima Supergroup along the Brazil-Guyana border in the Guiana shield, Northern Amazonian Craton - results of the Brazil-Guyana Geology and Geodiversity Mapping Project

    Directory of Open Access Journals (Sweden)

    Nelson Joaquim Reis

    Full Text Available ABSTRACT: The Geological and Geodiversity Mapping binational program along the Brazil-Guyana border zone allowed reviewing and integrating the stratigraphy and nomenclature of the Roraima Supergroup along the Pakaraima Sedimentary Block present in northeastern Brazil and western Guyana. The area mapped corresponds to a buffer zone of approximately 25 km in width on both sides of the border, of a region extending along the Maú-Ireng River between Mount Roraima (the triple-border region and Mutum Village in Brazil and Monkey Mountain in Guyana. The south border of the Roraima basin is overlain exclusively by effusive and volcaniclastic rocks of the Surumu Group of Brazil and its correlated equivalent the Burro-Burro Group of Guyana.

  9. Asymmetrical cross-current turbidite facies tract in a structurally-confined mini-basin (Priabonian-Rupelian, Ranzano Sandstone, northern Apennines, Italy)

    NARCIS (Netherlands)

    Tinterri, R.; Laporta, M.; Ogata, K.

    2017-01-01

    This work discusses the stratigraphy and facies analysis of the Ranzano Sandstone, in the northern Apennines (Italy), a confined low-efficiency turbidite system deposited in a series of small piggy-back basins, which show strong analogies with intraslope minibasins commonly observed in divergent

  10. National Account Energy Alliance Final Report for the Basin Electric Project at Northern Border Pipeline Company's Compressor Station #7, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    Sweetzer, Richard [Exergy Partners Corp.; Leslie, Neil [Gas Technology Institute

    2008-02-01

    A field research test and verification project was conducted at the recovered energy generation plant at Northern Border Pipeline Company Compressor Station #7 (CS#7) near St. Anthony. Recovered energy generation plant equipment was supplied and installed by ORMAT Technologies, Inc. Basin Electric is purchasing the electricity under a purchase power agreement with an ORMAT subsidiary, which owns and operates the plant.

  11. Influence of urbanization on the original vegetation cover in urban river basin: case study in Campinas/SP, Brazil

    Science.gov (United States)

    Leite Silva, Alessandra; Márcia Longo, Regina

    2017-04-01

    ABSTRACT: In most Brazilian municipalities, urban development was not based on adequate planning; one of the consequences was the reduction of the original vegetation, limiting the forest formations to scarce and isolated fragments. In Campinas, São Paulo, Brazil, the vegetation fragmentation was mainly related to the expeditions and to the cycles of sugar cane and coffee. In this way, the present study aims to identify, quantify and evaluate the remaining arboreal vegetation spatial distribution in the Anhumas River Basin - Campinas/SP, Brazil. This study was developed with the aid of GIS software and field visits in order to construct a diagnosis of these areas and subsidize future actions required and to discuss the influence of urbanization on the original vegetation cover. The area was initially occupied by the Atlantic Forest (semi-deciduous forest) and drains one of the oldest urban occupation areas in the municipality; according to researchers, based on the water and geomorphological conditions of the basin, it can be subdivided into high, medium and low course. With a total area of 156,514 km2, only 16.74% are classified as green areas; where just 1.07% and 6.17% of total area represents forests and reforestation areas, respectively. The remaining green areas consists of: wetlands close to water bodies, but with no presence of trees and shrubs (area of 0.12% of the basin); urban green space, including parks and squares (2.19%); and natural field, constituted by natural non-arboreous vegetation (7.18%). In a scenario like this, a characteristic situation is the forest fragmentation; this process results in native vegetation remnants, isolated and more susceptible to external interference, coming from, for example, the proximity to agricultural areas or others land uses. The ecological knowledge of the remnants and their correct management can not only make it possible to diagnose current problems and to estimate future influences, but also to point out the

  12. Tometes camunani (Characiformes: Serrasalmidae, a new species of phytophagous fish from the Guiana Shield, rio Trombetas basin, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo C. Andrade

    Full Text Available A new species of Serrasalmidae, Tometes camunani, is described from the upper drainages of the rio Trombetas basin, Pará State, Brazil. The new species is distinguished from its congeners by having neurocranium with a slight concavity at the level of the frontal bone (vs. concavity absent, dorsal profile of neurocranium straight. It can be further distinguished from its congeners by having teeth with central cusp taller and acute (vs. central cusp shorter and with rounded edge in T. trilobatus, a terminal mouth (vs. upturned mouth in T. lebaili, and 12-26 prepelvic spines (vs. 0-9 in T. makue. The new species is strictly rheophilic like other species of Tometes, and occurs exclusively in the rapids of shield rivers, complex and fragile biotopes that are threatened by anthropogenic activities. An identification key to the species of the Myleus group is provided

  13. Two new species of the Hypostomus cochliodon group (Siluriformes: Loricariidae from the rio Negro basin in Brazil

    Directory of Open Access Journals (Sweden)

    Pedro Hollanda Carvalho

    Full Text Available Two new species of Hypostomus are described from the middle and upper rio Negro in Brazil. They are assigned to the Hypostomus cochliodon group (sensu Armbruster, 2003 by possessing few spoon-shaped teeth, and dentary angle averaging less than 80º. Hypostomus kopeyaka is described from the rio Tiquié, a tributary of the rio Uaupés, upper rio Negro basin, presents a unique color pattern among the Hypostomus species belonging to the Hypostomus cochliodon group, consisting of conspicuously horizontally elongated, closely-set black spots over the entire dorsal and lateral surfaces of the body. Hypostomus weberi is described from the middle rio Negro and can be distinguished from all remaining Hypostomus species belonging to the Hypostomus cochliodon group by possessing a unique color pattern consisting in large, rounded, widelyspaced black spots over body and fins.

  14. Oligosarcus jacuiensis (Characiformes: Characidae, a new species from the Uruguay and Jacuí River basins, southern Brazil

    Directory of Open Access Journals (Sweden)

    Naércio Aquino Menezes

    Full Text Available The new species herein described, collected in the Jacuí and Uruguay River basins, Rio Grande do Sul, Brazil, can be distinguished from the already known species of the genus, but Oligosarcus jenynsii, O. perdido, O. acutirostris, O. solitarius and O. hepsetus, by the number of perforated lateral line scales. It shares with the first two species the absence of a premaxillary foramen, present in the last three species and differs from O. jenynsii by having a smaller orbital diameter and the tip of the pectoral fin failing to reach the pelvic-fin origin, and from O. perdido by the presence of more horizontal scale rows around the caudal peduncle.

  15. Prevalence of HCV infection and associated factors among illicit drug users in Breves, State of Pará, northern Brazil.

    Science.gov (United States)

    Pacheco, Suzy Danielly Barbosa; Silva-Oliveira, Gláucia Caroline; Maradei-Pereira, Luciana Maria Cunha; Crescente, José Ângelo Barletta; Lemos, José Alexandre Rodrigues de; Oliveira-Filho, Aldemir Branco de

    2014-01-01

    Illicit drug users (DUs) are vulnerable to hepatitis C virus (HCV) infection. The shared use of illicit drugs is the main method of HCV transmission. A cross-sectional study was conducted in Breves, in northern Brazil. We surveyed 187 DUs to determine the prevalence of and factors associated with HCV infection. The prevalence of anti-HCV antibodies was 36.9%, and the prevalence of hepatitis C virus-ribonucleic acid (HCV-RNA) was 31%. Hepatitis C virus infection was associated with tattoos, intravenous drug use, shared use of equipment for drug use, drug use for longer than 3 years, and daily drug use. Strategies for preventing and controlling HCV transmission should be implemented among DUs.

  16. Prevalence of HCV infection and associated factors among illicit drug users in Breves, State of Pará, northern Brazil

    Directory of Open Access Journals (Sweden)

    Suzy Danielly Barbosa Pacheco

    2014-06-01

    Full Text Available Introduction: Illicit drug users (DUs are vulnerable to hepatitis C virus (HCV infection. The shared use of illicit drugs is the main method of HCV transmission. Methods: A cross-sectional study was conducted in Breves, in northern Brazil. We surveyed 187 DUs to determine the prevalence of and factors associated with HCV infection. Results: The prevalence of anti-HCV antibodies was 36.9%, and the prevalence of hepatitis C virus-ribonucleic acid (HCV-RNA was 31%. Hepatitis C virus infection was associated with tattoos, intravenous drug use, shared use of equipment for drug use, drug use for longer than 3 years, and daily drug use. Conclusions: Strategies for preventing and controlling HCV transmission should be implemented among DUs.

  17. Evaluation of uranium anomalies in the Hylas zone and northern Richmond basin, east-central Virginia

    International Nuclear Information System (INIS)

    Baillieul, T.A.; Dexter, J.J.

    1982-01-01

    Conclusions from this study are: (1) Radon values in ground water from the Hylas Zone and the adjacent Richmomd Basin are anomalous and may indicate nearby uranium-enriched source rocks. (2) Pegmatites, protomylonitic granite, and the Petersburg Granite can be good sources of uranium for ground water. The pegmatites described in this report appear to be the best source rocks because of uranium values ranging from 82 to 235 ppM eU and corresponding low values of Th as well (average Th/U = 0.18). The protomylonitic granite has an average Th/U ratio of 0.5. Ground-water samples (ranging from 70 to 270 ppB uranium) from southwest Richmond are believed to have originated from a major ground-water system at the contact of the Petersburg Granite and overlying coastal plain sediments. Thus, the Petersburg Granite may be considered a possible source of uranium available to ground water entering the Richmond Basin. (3) The Richmond Basin could host uranium deposits of the sandstone class. As mentioned above, there appears to be an adequate supply of uranium in rocks surrounding the basin. The basin environment is presently classified as unevaluated. Further work is warranted on the basis of this study. (4) Pegmatites in the Hylas Zone could be favorable for the occurrence of uranium deposits of the pegmatitic class. However, it is not known how the uranium occurs in the pegmatites, and only pegmatites exposed in the Boscobel quarry were examined. Therefore, this environment remains unevaluated. 3 figures, 4 tables

  18. Deformation bands in porous sandstone: case study in basins of northeast Brazil; Bandas de deformacao em arenitos porosos: estudo de casos em bacias do nordeste do Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Talles Souza [PETROBRAS, RN (Brazil). Interpretacao e Avaliacao de bacias da Costa Leste do Brasil E and P. Gerencia de Interpretacao], e-mail: tallesferreira@petrobras.com.br; Silva, Fernando Cesar Alves da [Universidade Federal do Rio Grande do Norte (UFRN). Dept. de Geologia Programa de Pos-Graduacao em Geodinamica e Geofisica (Brazil)], e-mail: fernando@geologia.ufrn.br

    2010-05-15

    The meso and microscopic scale sandstone characterizations of the deformation bands of three sedimentary basins in northeastern Brazil; the Potiguar and Sergipe-Alagoas basins (Brazilian Atlantic Margin) and the Tucano Basin (aborted rift basin) were compared for their similarities and differences. Deformation bands are structures commonly developed in porous sandstones that make up the main reservoir-rock in siliciclastic petroleum systems. These structures influence the permo-porous properties and consequently the migration pathway into a sandstone reservoir. To understand their formation process and development has been the focus of a great number of articles in recent petroleum geology literature. This study highlights the similarities and the differences in the features and deformation mechanisms that provoked the development of deformation bands in the damage zones of major faults in three different sedimentary basins. In terms of basin tectonics, the deformation bands' formation and geometric arrangements are associated with major structures. In the case of the Acu Formation, a correlation was observed with the dextral Afonso Bezerra fault system, whereas in the Sergipe-Alagoas Basin the normal dextral strike-slip faults can be associated with the faulting of the boarder basin. In the Tucano Basin case, the deformation basins are related to the Jeremoabo transpressional fault, a major structure a few kilometers to the north. This study applies structural geology tools to better understand the geometric arrangement and growing mechanisms of deformation bands in different lithological and tectonic settings. Although the deformation bands present a similar aspect in a macroscopic view, the interplay between depositional and mineralogical parameters of the host rock, as well as the basin's burial and tectonic history resulted in the development of different sandstone deformation bands in three northeastern brazilian basins. (author)

  19. The zooplankton biodiversity of some freshwater environments in Parnaíba basin (Piauí, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    JDN. Paranhos

    Full Text Available The plankton fauna of the state of Piauí, Northeastern Brazil, especially in the Parnaíba basin, is still poorly known; the results of most studies of the subject have not been published and can only be found in grey literature (unpublished scientific works, such as course completion work and consulting reports. Thus, this paper presents data from samples taken recently from different water bodies in Piauí and represents the second study to be published on the region's zooplankton since the pioneering work of Spandl (1926. A total of 38 species were recorded, including 23 new occurrences of rotifers, 10 of cladocerans and 2 of copepods for the state of Piauí. The greatest richness was observed for the rotifers, of which the genus Brachionus must be highlighted, especially at the Joana reservoir. Among the crustaceans, the greatest richness was observed at the Bezerra reservoir, where cladocerans of the genus Bosmina were prominent. The rotifers Brachionus havanaensis Rousselet, 1911 and Filinia longiseta (Ehrenberg, 1834; the cladocerans Diaphanosoma spinulosum Herbst, 1967 and Moina micrura Kurz, 1874; and the copepods Notodiaptomus cearensis Wright, 1936 and Thermocyclops decipiens Kiefer, 1927 occurred in all or in most environments in which the respective groups were studied. The results presented here expand the taxonomic list of zooplankton for the state of Piauí, including a total fauna of 30 species of rotifers, 15 of cladocerans and 3 of copepods. The zooplankton richness was considered low in the studied reservoirs compared to other freshwater ecosystems from Northeastern Brazil; however, the few studies developed in the Parnaíba basin suggest that the diversity for these organisms should be higher.

  20. Occurrence of female sexual hormones in the Iguazu river basin, Curitiba, Paraná State, Brazil

    Directory of Open Access Journals (Sweden)

    Karina Scurupa Machado

    2014-02-01

    Full Text Available Female sexual hormones have attracted the attention of the scientific community due to the effects that they cause by interfering in the endocrine system. Many contemporary studies have sought to monitor some of the main female sexual hormones in surface waters in Brazil. Current article evaluates the presence of 17β-estradiol, 17α-ethinylestradiol, estrone and progesterone in the surface waters of Curitibaand the surrounding metropolitan area in the state of Paraná, Brazil, by high-performance liquid chromatography (HPLC, performed at 7 different sites. The study revealed that a range of concentrations between 0.07 and 13.45 µg L-1 of female sexual hormones was extant; higher values than these were found in other regions ofBrazil and in other countries. Higher concentrations have been attributed to the region´s sanitation due to large sewage amounts. Sewage discharge has also been confirmed by results of limnological parameters.

  1. Gravity anomalies and flexure of the lithosphere at the Middle Amazon Basin, Brazil

    Science.gov (United States)

    Nunn, Jeffrey A.; Aires, Jose R.

    1988-01-01

    The Middle Amazon Basin is a large Paleozoic sedimentary basin on the Amazonian craton in South America. It contains up to 7 km of mainly shallow water sediments. A chain of Bouguer gravity highs of approximately +40 to +90 mGals transects the basin roughly coincident with the axis of maximum thickness of sediment. The gravity highs are flanked on either side by gravity lows of approximately -40 mGals. The observed gravity anomalies can be explained by a steeply sided zone of high density in the lower crust varying in width from 100 to 200 km wide. Within this region, the continental crust has been intruded/replaced by more dense material to more than half its original thickness of 45-50 km. The much wider sedimentary basin results from regional compensation of the subsurface load and the subsequent load of accumulated sediments by flexure of the lithosphere. The observed geometry of the basin is consistent with an elastic lithosphere model with a mechanical thickness of 15-20 km. Although this value is lower than expected for a stable cratonic region of Early Proterozoic age, it is within the accepted range of effective elastic thicknesses for the earth. Rapid subsidence during the late Paleozoic may be evidence of a second tectonic event or lithospheric relaxation which could lower the effective mechanical thickness of the lithosphere. The high-density zone in the lower crust, as delineated by gravity and flexural modeling, has a complex sinuous geometry which is narrow and south of the axis of maximum sediment thickness on the east and west margins and wide and offset to the north in the center of the basin. The linear trough geometry of the basin itself is a result of smoothing by regional compensation of the load in the lower crust.

  2. Characterization of hepatitis B virus infection in illicit drug users in the Marajó Archipelago, northern Brazil.

    Science.gov (United States)

    Andrade, Andréia P; Pacheco, Suzy D B; Silva, Fabricio Q; Pinheiro, Luiz M L; Castro, Jairo A A; Amaral, Carlos E M; Hermes, Renata B; Fischer, Benedikt; Pinho, João R R; Lemos, José Alexandre R; Oliveira-Filho, Aldemir B

    2017-01-01

    South America is considered to have a low prevalence of hepatitis B virus (HBV) infection, although areas with a relatively high prevalence have been identified in northern Brazil. Few epidemiological studies of populations at risk of HBV infection are available for this region. Given this, in the present study, we investigated the prevalence of HBV and the factors associated with infection among illicit drug users (DUs) in the Marajó Archipelago, northern Brazil. In this cross-sectional study, we collected samples and epidemiological information from DUs in 11 municipalities of the Marajó Archipelago. The diagnosis was established by ELISA and real-time PCR; and genotyping was done by multiplex real-time PCR. Statistical modeling was based on simple and multiple logistical regressions with the Hosmer-Lemeshow test. The mean age of the 466 DUs was 28.4 years, and most were male. The most-consumed illicit drugs were crack cocaine and marijuana. In all, 171 DUs were exposed to HBV, with genotypes A, D and F being identified. The factors associated with higher frequencies of HBV infection were (i) male gender, (ii) age above 35 years, (iii) anti-HIV positivity, (iv) tattoos, (v) the use of injected drugs, (vi) the use of illicit drugs for more than 3 years, (vii) sexual relations without protection, (viii) sexual relations with another DU, and (ix) more than 10 sexual partners in the past 24 months. In summary, this study provides important insights into the dynamics of HBV infection among DUs in the Marajó Archipelago. We hope that these findings will contribute to the development of strategies, actions and public health policies aimed at preventing and controlling this viral infection more effectively.

  3. An integrated quantitative basin analysis study of the northern part of the Arctic national Wildlife Refuge, Northeastern Alaska

    Science.gov (United States)

    Yu, Z.; Lerche, Ian

    1992-06-01

    An integrated basin analysis was conducted using one- and two-dimensional quantitative dynamic models (1-D and 2-D) in the northern part of the Arctic National Wildlife Refuge (ANWR), Northeastern Alaska. Exploratory well data have been used in the reconstructions of: (1) geohistory including basement subsidence, sediment deposition, change of porosity and compaction, permeability, fluid pressure and fluid flow with time and depth; (2) thermal history including heat flux evolution with time, temperature change with time and depth, and thermal maturation history; and (3) hydrocarbon generation history including the change in the amount of hydrocarbons generated with time and depth, and determining the time and depth of peak hydrocarbon generation. 1-D and 2-D basin modeling codes were used with selected wells, and also with a 18 km section, west of ANWR, with five well controls. It is concluded that: (1) the main source rock west of ANWR area matured first about 40-30 Ma ago in the south and gradually to the north about 10-8 Ma ago on the coastal plain; (2) the modeled erosion thickness at Beli Unit-1 location, northeastern Brooks Range, was 1500-3000 m and at least 3000 m at Canning River Unit B-1; and (3) an overpressure zone within the Hue shale and the lowest part of the Canning Formation caused by rapid Tertiary deposition retained porosity, increased the temperature and speeded hydrocarbon generation in the lower part of the coastal plain.

  4. Flood-tracking chart for the Withlacoochee and Little River Basins in south-central Georgia and northern Florida

    Science.gov (United States)

    Gotvald, Anthony J.; McCallum, Brian E.; Painter, Jaime A.

    2014-01-01

    The U.S. Geological Survey (USGS), in cooperation with other Federal, State, and local agencies, operates a flood-monitoring system in the Withlacoochee and Little River Basins. This system is a network of automated river stage stations (ten are shown on page 2 of this publication) that transmit stage data through satellite telemetry to the USGS in Atlanta, Georgia and the National Weather Service (NWS) in Peachtree City, Georgia. During floods, the public and emergency response agencies use this information to make decisions about road closures, evacuations, and other public safety issues. This Withlacoochee and Little River Basins flood-tracking chart can be used by local citizens and emergency response personnel to record the latest river stage and predicted flood-crest information along the Withlacoochee River, Little River, and Okapilco Creek in south-central Georgia and northern Florida. By comparing the current stage (water-surface level above a datum) and predicted flood crest to the recorded peak stages of previous floods, emergency response personnel and residents can make informed decisions concerning the threat to life and property.

  5. Extraction and Validation of Geomorphological Features from EU-DEM in The Vicinity of the Mygdonia Basin, Northern Greece

    Science.gov (United States)

    Mouratidis, Antonios; Karadimou, Georgia; Ampatzidis, Dimitrios

    2017-12-01

    The European Union Digital Elevation Model (EU-DEM) is a relatively new, hybrid elevation product, principally based on SRTM DEM and ASTER GDEM data, but also on publically available Russian topographic maps for regions north of 60° N. More specifically, EU-DEM is a Digital Surface Model (DSM) over Europe from the Global Monitoring for Environment and Security (GMES) Reference Data Access (RDA) project - a realisation of the Copernicus (former GMES) programme, managed by the European Commission/DG Enterprise and Industry. Even if EU-DEM is indeed more reliable in terms of elevation accuracy than its constituents, it ought to be noted that it is not representative of the original elevation measurements, but is rather a secondary (mathematical) product. Therefore, for specific applications, such as those of geomorphological interest, artefacts may be induced. To this end, the purpose of this paper is to investigate the performance of EU-DEM for geomorphological applications and compare it against other available datasets, i.e. topographic maps and (almost) global DEMs such as SRTM, ASTER-GDEM and WorldDEM™. This initial investigation is carried out in Central Macedonia, Northern Greece, in the vicinity of the Mygdonia basin, which corresponds to an area of particular interest for several geoscience applications. This area has also been serving as a test site for the systematic validation of DEMs for more than a decade. Consequently, extensive elevation datasets and experience have been accumulated over the years, rendering the evaluation of new elevation products a coherent and useful exercise on a local to regional scale. In this context, relief classification, drainage basin delineation, slope and slope aspect, as well as extraction and classification of drainage network are performed and validated among the aforementioned elevation sources. The achieved results focus on qualitative and quantitative aspects of automatic geomorphological feature extraction from

  6. Dinosaur ichnofauna of the Upper Jurassic/Lower Cretaceous of the Paraná Basin (Brazil and Uruguay)

    Science.gov (United States)

    Francischini, H.; Dentzien–Dias, P. C.; Fernandes, M. A.; Schultz, C. L.

    2015-11-01

    Upper Jurassic and Lower Cretaceous sedimentary layers are represented in the Brazilian Paraná Basin by the fluvio-aeolian Guará Formation and the Botucatu Formation palaeoerg, respectively, overlapped by the volcanic Serra Geral Formation. In Uruguay, the corresponding sedimentary units are named Batoví and Rivera Members (both from the Tacuarembó Formation), and the lava flows constitute the Arapey Formation (also in Paraná Basin). Despite the lack of body fossils in the mentioned Brazilian formations, Guará/Batoví dinosaur fauna is composed of theropod, ornithopod and wide-gauge sauropod tracks and isolated footprints, as well as theropod teeth. In turn, the Botucatu/Rivera dinosaur fauna is represented by theropod and ornithopod ichnofossils smaller than those from the underlying units. The analysis of these dinosaur ichnological records and comparisons with other global Mesozoic ichnofauna indicates that there is a size reduction in dinosaur fauna in the more arid Botucatu/Rivera environment, which is dominated by aeolian dunes. The absence of sauropod trackways in the Botucatu Sandstone fits with the increasingly arid conditions because it is difficult for heavy animals to walk on sandy dunes, as well as to obtain the required amount of food resources. This comparison between the Upper Jurassic and Lower Cretaceous dinosaur fauna in south Brazil and Uruguay demonstrates the influence of aridization on the size of animals occupying each habitat.

  7. Disentangling the influences of habitat structure and limnological predictors on stream fish communities of a coastal basin, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Fabio Cop Ferreira

    Full Text Available In stream environments habitat structure and limnological factors interact regulating patterns of energy and material transfer and affecting fish communities. In the coastal basins of Southeastern Brazil, limnological and structural characteristics differ between clear and blackwaters streams. The former have a diversity of substrate types, higher water velocities, and lower water conductivity, while the latter have sandy substrate, tea-colored and acidic waters, and low water velocities. In this study, we verified the relative importance of habitat structure and limnological variables in predicting patterns of variation in stream fish communities. Eight first to third order streams were sampled in the coastal plain of Itanhaém River basin. We captured 34 fish species and verified that community structure was influenced by physical habitat and limnology, being the former more important. A fraction of the variation could not be totally decomposed, and it was assigned to the joint influence of limnology and habitat structure. Some species that were restricted to blackwater streams, may have physiological and behavioral adaptations to deal with the lower pH levels. When we examined only the clearwater streams, all the explained variation in fish community composition was assigned to structural factors, which express specific preferences for different types of habitats.

  8. GROUNDWATER QUALITY EVALUATION OF PERMANENT PRESERVATION AREAS (GUARANI AQUIFER SYSTEM - GAS, RIO PARDO HYDROGRAPHICAL BASIN, RS, BRAZIL

    Directory of Open Access Journals (Sweden)

    Adilson Ben da Costa

    2010-06-01

    Full Text Available The aim of this research was to evaluate the quality of groundwater in areas of permanent preservation (Guarani Aquifer System – GAS in the Rio Pardo Hydrographical Basin, RS, Brazil, using physical, chemical and microbiological variables, based on resolution no. 396/2008 of the National Council on the Environment - CONAMA. Nine sampling points were distributed throughout the basin, where groundwater was classified as the major ions through the Piper diagram. The results indicated that most of the wells evaluated were classified in Class 4, accounting for water uses less restrictive. However, it should be considered that the aquifers are characterize by different geological conditions, having intrinsical physical, chemical and biological variables with hydrogeochemical variations, requiring that their quality levels are often based on these characteristics, as noted in diagram Piper, where the samples P1, P2, P3, P5 and P9 were classified as calcium bicarbonate, the waters of the points P4, P6, P7 as sodium bicarbonate and P8 as sulfated. It was found that the quality of water from wells with depths less than 6 m are becoming more vulnerable due to anthropogenic activities, as showing by the concentration of nitrate, total and thermotolerant coliforms, while the quality of water from deeper wells basically depends on their hydrogeological and hydrogeochemical characteristics based on the concentration of sodium and sulfate variables. However, they also showed contamination by human activities, mainly by the nitrate variable.

  9. Seasonal study of contamination by metal in water and sediment in a sub-basin in the southeast of Brazil

    Directory of Open Access Journals (Sweden)

    WAC. Chiba

    Full Text Available The spatial and temporal occurrence of heavy metals (Al, Cd, Pb, Zn, Cr, Co, Cu, Fe, Mn and Ni in water and sediment samples was investigated in a sub-basin in the southeast of Brazil (São Carlos, SP. All samples were analysed using the USEPA adapted metal method and processed in an atomic absorption spectrophotometer. The discriminant analysis demonstrated that there are significant seasonal differences of metal distribution in the water data, but there are no differences to sediment. The basin studied has high levels of contamination by toxic metals in superficial water and sediment. The superficial water, in the rainy season, presented high levels of Cr, Ni, Pb and Cd, while in the dry season it presented high levels of Zn and Ni. The Principal Component Analysis demonstrated that the season has a huge influence on the levels, types and distribution of metals found in water. The source of contamination was probably diffuse, due to products such as batteries and fluorescent lamps, whose dump discharge can contaminate the bodies of water in the region in the rainy season. Due to fires from the harvest of sugar cane, high levels of Zn were found into the environment, in the dry season.

  10. Corridors of crestal and radial faults linking salt diapirs in the Espírito Santo Basin, SE Brazil

    Science.gov (United States)

    Mattos, Nathalia H.; Alves, Tiago M.

    2018-03-01

    This work uses high-quality 3D seismic data to assess the geometry of fault families around salt diapirs in SE Brazil (Espírito Santo Basin). It aims at evaluating the timings of fault growth, and suggests the generation of corridors for fluid migration linking discrete salt diapirs. Three salt diapirs, one salt ridge, and five fault families were identified based on their geometry and relative locations. Displacement-length (D-x) plots, Throw-depth (T-z) data and structural maps indicate that faults consist of multiple segments that were reactivated by dip-linkage following a preferential NE-SW direction. This style of reactivation and linkage is distinct from other sectors of the Espírito Santo Basin where the preferential mode of reactivation is by upwards vertical propagation. Reactivation of faults above a Mid-Eocene unconformity is also scarce in the study area. Conversely, two halokinetic episodes dated as Cretaceous and Paleogene are interpreted below a Mid-Eocene unconformity. This work is important as it recognises the juxtaposition of permeable strata across faults as marking the generation of fault corridors linking adjacent salt structures. In such a setting, fault modelling shows that fluid will migrate towards the shallower salt structures along the fault corridors first identified in this work.

  11. Deep-water Mangeliinae, Taraninae and Clathurellinae (Mollusca: Gastropoda: Conoidea: Turridae from the Campos Basin, southeast Brazil

    Directory of Open Access Journals (Sweden)

    Raquel Medeiros Andrade Figueira

    2010-11-01

    Full Text Available During the program “Environmental Characterization of the Campos Basin, RJ, Brazil”, from 2001 to 2003, samples were taken of soft bottoms from the continental slope of Campos Basin (off southeast Brazil by the Research Vessel “Astro-Garoupa” with a 0.25 m2 box corer or by dredging with a Charcot dredge; 117 stations with depths from 700 to 1950 m were sampled. There were molluscs in all samples, and among Gastropoda the Turridae showed the highest diversity. Here we present the results obtained for the subfamilies Mangeliinae, Taraninae and Clathurellinae. Two species were found within Mangeliinae: Benthomangelia cf. macra (Watson, 1881 and Benthomangelia enceladus n. sp. Within Taraninae only one undescribed species was found: Taranis tanata n. sp. Within Clathurellinae we found four species: Corinnaeturris leucomata (Dall, 1881, recorded for the first time in the South Atlantic; Corinnaeturris rhysa (Watson, 1881, extending its described depth range; Corinnaeturris angularis n. sp., Typhlomangelia nivalis (Lovén, 1846, expanding its known distribution farther south; and Drilliola pulchella (Verrill, 1880. The type material of Drilliola loprestiana (Calcara, 1841, previously considered lost, has been located and is illustrated here. Drilliola crispata (Cristofori and Jan, 1832 is considered to be a nomen dubium.

  12. Fish, lower Ivinhema River basin streams, state of Mato Grosso do Sul, Brazil.

    Directory of Open Access Journals (Sweden)

    Súarez, Y. R.

    2008-01-01

    Full Text Available The Ivinhema River basin is one of the main tributaries of the western portion of Paraná River. However,few data are available on the fish communities of its streams. Monthly samples were made in seven streams of the lowerportion of the basin, in the state of Mato Grosso do Sul, using a rectangular sieve 1.2 x 0.8 m, with 2 mm mesh size.Forty-six fish species were found in these streams. The richness estimated according to the bootstrap procedure was 50species. At least two of the captured species were not previously recorded for the upper Paraná basin, indicating theneed of new sampling effort in this region.

  13. Soil map, area and volume calculations in Orrmyrberget catchment basin at Gideaa, Northern Sweden

    International Nuclear Information System (INIS)

    Ittner, T.; Tammela, P.T.; Gustafsson, E.

    1991-06-01

    Fallout studies in the Gideaa study site after the Chernobyl fallout in 1986, has come to the point that a more exact surface mapping of the studied catchment basin is needed. This surface mapping is mainly made for area calculations of different soil types within the study site. The mapping focus on the surface, as the study concerns fallout redistribution and it is extended to also include materials down to a depth of 0.5 meter. Volume calculations are made for the various soil materials within the top 0.5 m. These volume and area calculations will then be used in the modelling of the migration and redistribution of the fallout radionuclides within the studied catchment basin. (au)

  14. Description of a new species of Microglanis (Siluriformes: Pseudopimelodidae from the Amazon basin, Amazonas State, Brazil

    Directory of Open Access Journals (Sweden)

    Lucas Ribeiro Jarduli

    Full Text Available The first species of Microglanis from the rio Amazonas, Amazonas State, Brazil is described. This species differs from all congeners by the forked caudal fin, and color pattern of the supraoccipital region consisting of two elliptical and juxtaposed pale spots, besides a combination of morphometrics characters.

  15. Actual stage of organic geochemical knowledge from Campos and Espirito Santo basins, Brazil

    International Nuclear Information System (INIS)

    Gaglianone, P.C.; Trindade, L.A.F.

    1987-01-01

    Campos and Espirito Santo basins display several similar geochemical aspects. The microbial and other degradation processes caused changes in the composition of the oils in the reservoir rocks. The oils are biodegraded in different degrees, with the reservoir temperature developing an important role in the control of the biodegradation process. The migration pathway model is similar for Campos and Espirito Santo basins, involving the upward secondary migration through a window in the evaporitic seals. The oils passed to the marine sequence where migration and accumulation were controlled by faults, regional unconformities and by reservoirs. The geochemical correlation of oils are realized by gaseous and liquid chromatography analysis, carbon isotopes and biolabelled compounds. (author)

  16. Uranium prospecting in Cerro Partido Region-Encruzilhada do Sul Basin-RS, Brazil

    International Nuclear Information System (INIS)

    Fraenkel, M.O.

    1974-01-01

    The Cerro Partido residual basin is a shallow (85 meters) and small (25km 2 ) sedimentary basin, a remainder of the erosive cicle, enclosed in the pre-cambrian granitic rocks of the Rio Grande do Sul Shield. Grades of 0.2 + U 3 O 8 were found in its upper-paleozoic sandstones and shales drilles for uranium. The small size and thicknesses of these concentrations prevent their economic mining. However, the different levels of the shield exposed by tectonics, the intrusive granitic, riolitic and syenitic rocks, the anomalous uranium contents in sedimentary and crystalline rocks recommend further investigations on the shield area

  17. Carbonate and lignite cycles in the Ptolemais Basin: Orbital control and suborbital variability (Late Neogene, northern Greece)

    Science.gov (United States)

    Weber, M. E.; Tougiannidis, N.; Ricken, W.; Rolf, C.; Kleineder, M.; Bertram, N.; Antoniadis, P.

    2009-04-01

    We recently commenced a project to investigate deep drillings as well as outcrops in the Ptolemais Basin, northern Greece, for paleoenvironmental and paleoclimate change. Specific attention is paid to mining sites Achlada, Vevi, Vegora, Amynteon, North Field, South Field, and Lava. The sediment archive comprises Upper Miocene to Quaternary continental lake deposits (up to 800 m thick) with an extended Lower Pliocene section. The Upper Miocene sections are composed of diatomaceous mud and gray marls. Pliocene lake sediments commence with the Kyrio member (lignite/grey marl), followed by the Theodoxus member (beige marl/lignite), and the Notio member (marl with intercalated sand /lignite). The limnic deposits show striking rhythmic bedding of (mostly) carbonates and lignites, reflecting orbital-induced humidity and temperature changes in this small NW-SE elongated continental basin. First, we retrieved chronometric information by determining magnetic polarity changes on three sites as independent stratigraphic ground-truth in combination with palynological evidence and published data. Then we conducted a number of high-resolution (1 - 6 cm increment), non-destructive measurements to obtain paleoclimate proxies: photospectrometry (colors L, a, b), magnetic susceptibility, and natural gamma. Accordingly, we achieved a multi-proxy insight into paleoclimate and paleoenvironmental evolution at unprecedented temporal resolution (up to a few decades!) over long time series and at a number of key sites. Using the newly-developed ESALab software, we conducted spectral and evolutionary spectral analysis to evaluate the cyclo-stratigraphic development. As for orbital variability, spectral power is concentrated on precession, hemi-precession, and eccentricity, with only minor impact of orbital tilt. We used this information to increase the temporal resolution of our age models by tuning as many precession (insolation) maxima as possible to carbonate minima (lignite maxima

  18. Hydrogeochemical studies of historical mining areas in the Humboldt River basin and adjacent areas, northern Nevada

    Science.gov (United States)

    Nash, J. Thomas

    2005-01-01

    The study area comprises the Humboldt River Basin and adjacent areas, with emphasis on mining areas relatively close to the Humboldt River. The basin comprises about 16,840 mi2 or 10,800,000 acres. The mineral resources of the Humboldt Basin have been investigated by many scientists over the past 100 years, but only recently has our knowledge of regional geology and mine geology been applied to the understanding and evaluation of mining effects on water and environmental quality. The investigations reported here apply some of the techniques and perspectives developed in the Abandoned Mine Lands Initiative (AMLI) of the U.S. Geological Survey (USGS), a program of integrated geological-hydrological-biological-chemical studies underway in the Upper Animas River watershed in Colorado and the Boulder River watershed in, Montana. The goal of my studies of sites and districts is to determine the character of mining-related contamination that is actively or potentially a threat to water quality and to estimate the potential for natural attenuation of that contamination. These geology-based studies and recommendations differ in matters of emphasis and data collection from the biology-based assessments that are the cornerstone of environmental regulations.

  19. Evaporite dissolution relevant to the WIPP site, northern Delaware Basin, southeastern New Mexico

    International Nuclear Information System (INIS)

    Lambert, S.J.

    1982-01-01

    Evaluation of the threat of natural dissolution of host evaporites to the integrity of the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico has taken into consideration (1) the volume of missing rock salt, (2) the occurrence (or not) of characteristic dissolution brines, (3) geomorphic features, some of which are unrelated to dissolution, and (4) the time intervals over which dissolution may have been active. Even under the assumption that all missing halite was originally present and has been removed by dissolution, there is no evidence of active preferential removal of the lower Salado Formation halite by any geologically reasonable process. The geologic record contains evidence of dissolution in the Triassic and Jurassic; to constrain all removal of basinal halite to the late Cenozoic yields an unrealistically high rate of removal. Application to the lower Salado of a stratabound mechanism known to be active in Nash Draw, a near-surface feature within the Basin, allows a minimum survival time of 2,500,000 years to be predicted for the subsurface facility for storage of radioactive waste at WIPP. This calculation is based on an analysis of all known dissolution features in the Delaware Basin, and takes into account the wetter (pluvial) climate during the past 600,000 years. 2 figures, 1 table

  20. Tectonic-stratigraphic evolution of mini-basins and salt provinces of Espirito Santo Basin-Brazil; Analise da evolucao tectono sedimentar de mini-bacias e provincias de sal da Bacia do Espirito Santo

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Neto, Walter Dias; Fernandes, Flavio Luis [Petroleum Geoscience Technology Ltda. (PGT), Rio de Janeiro, RJ (Brazil); Mohriak, Webster [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The Espirito Santo Basin integrates the group of basins along the eastern Brazilian continental margin. It is located between 18 deg and 21 deg S, encompassing an area of approximately 220,000 km{sup 2}, onshore and offshore the Espirito Santo State. Its geological limit with the Campos Basin to the south is defined by a Precambrian basement high (Vitoria Arch), and its northern limit with the Mucuri Basin is defined by a geopolitical limit. The study of salt tectonics processes in the Espirito Santo Basin allowed the deformational analysis and interpretation of the chronological evolution of the mini-basins developed between salt diapirs. We observe an intrinsic relationship between halokinesis and creation of subsidence troughs that may be important for trapping hydrocarbon reservoirs, and consequently form oil and gas accumulations in this portion of the basin. This geodynamics evolution of these structures is marked by a strong linkage between salt movement and coeval sedimentation in the interdomal basins, forming structures and stratigraphic traps that may constitute important aspects for the petroleum geology. (author)

  1. Geochronologic study of sediments deposition of two lakes from the Rio Negro basin, Amazonas State, Brazil

    International Nuclear Information System (INIS)

    Gomes, Ana Carla F.; Mozeto, Antonio A.; Cazotti, Raul I.; Nascimento Filho, Virgilio F.; Taddei, Maria Helena

    2000-01-01

    Since 1963 the radionuclide 210 Pb became an important tool for dating (geochronology) recent sediments (up to 120 years). In this work the sedimentary geochronology of two lakes from the Negro River Basin was determined, using different radiochemical separation methods for 210 Pb and 226 Ra. (author)

  2. Miocene fish faunas from the northwestern Amazonia basin (Colombia, Peru, Brazil) with evidence of marine incursions

    NARCIS (Netherlands)

    Monsch, KA

    1998-01-01

    New evidence indicates marine influences during the Miocene in the northwestern Amazonia basin. This is the first major survey of the ichthyofauna from this area in the Miocene. Fossil fish remains from taxa such as the Dasyatoidea, Myliobatoidea, Characiformes, Siluriformes and Sciaenidae are

  3. The Research of Tectonic Framework and the Fault Activity in Large Detachment Basin System on Northern Margin of South China Sea

    Science.gov (United States)

    Pan, L., Sr.; Ren, J.

    2017-12-01

    The South China Sea (SCS) is one of the largest marginal sea on southeast Asia continental margin, developed Paleogene extension-rifting continental margin system which is rare in the world and preserving many deformed characterizes of this kind system. With the investigation of the SCS, guiding by the development of tectonics and geo-physics, especially the development of tectonics and the high quality seismic data based on the development of geo-physics, people gradually accept that the northern margin of the SCS has some detachment basin characterizes. After researching the northern margin of the SCS, we come up with lithosphere profiles across the shelf, slope and deep sea basin in the northeast of the SCS to confirm the tectonic style of ocean-continental transition and the property of the detachment fault. Furthermore, we describe the outline of large detachment basins at northern SCS. Based on the large number of high-quality 2D and 3D deep seismic profile(TWT,10s), drilling and logging data, combined with domestic and international relevant researches, using basin dynamics and tectono-stratigraphy theory, techniques and methods of geology and geophysics, qualitative and quantitative, we describe the formation of the detachment basin and calculate the fault activity rate, stretching factor and settlement. According to the research, we propose that there is a giant and complete detachment basin system in the northern SCS and suggest three conclusions. First of all, the detachment basin system can be divided into three domains: proximal domain covering the Yangjiang Sag, Shenhu uplift and part of Shunde Sag, necking zone covering part of the Shunde Sag and Heshan Sag, distal domain covering most part of Heshan Sag. Second, the difference of the stretching factor is observed along the three domains of the detachment basin system. The factor of the proximal domain is the minimum among them. On the other side, the distal domain is the maximum among them. This

  4. Reinterpretation of the tectonics and formation of the Pernambuco Plateau Basin, NE Brazil.

    Science.gov (United States)

    Hoggett, Murray; Jones, Stephen M.; Dunkley Jones, Tom; Reston, Timothy; Barbosa, Antonio; Biondo, Vanessa; Mort, Haydon P.

    2017-04-01

    The continental margin from Alagoas to Natal represents arguably the most frontier region for exploration on the Brazillian margin. High quality seismic data was not collected in the region for many decades as it was believed that only a few kilometers of sediment existed, and thus there was no exploration potential. Here we present the results of work done as part of an IODP virtual site survey. The work has resulted in a total reinterpretation of the basin structure and tectonics, including finding sediment filled half grabens holding up to 8km thick stratigraphic sections. The two deepest grabens likely represent rift jumps during breakup, which may imply different age sediments in the different grabens. The basin is also found to contain a sizable salt accumulation, previously uninterpreted due to hard overlying carbonates hampering seismic imaging. This salt can be seen to have been highly mobile in the past, and has developed into kilometer scale diapirs flanked by typical rollover anticlines. For the first time we show the basin has all the elements needed for a working petroleum system, with the exception a source rock - which cannot be speculated on further as the basin is undrilled. However source rock sequences are present in the Alagoas basin to the south, and recent released seep data show evidence for both biogeneic and thermogenic seeps over the plateau basin, which could also signal source rock presence. We present seismic and potential fields data, including forward potential fields models and seismically derived crustal stretching and thinning estimates, to show that the half grabens terminate abruptly at the latitude of the Pernambuco Shear Zone, a major crustal scale Precambrian shear zone. Onshore boreholes, well away from the deep seismically imaged half grabens offshore, find crystalline basement to drop away rapidly across the shearzone, revealing a third graben to terminate at the shear zone. We interpret this as that the preexisting

  5. The intraplate Maranhão earthquake of 2017 January 3, northern Brazil: evidence for uniform regional stresses along the Brazilian equatorial margin

    Science.gov (United States)

    Dias, Fábio L.; Assumpção, M.; Bianchi, Marcelo B.; Barros, Lucas V.; Carvalho, Juraci M.

    2018-04-01

    Lithospheric stresses in intraplate regions can be characterized by many different wavelengths. In some areas, stresses vary over short distances of less than ˜100 km, but in other regions uniform stresses can be recognized for more than ˜1000 km or so. However, not all intraplate regions are well sampled with stress measurements to allow a good characterization of the lithospheric stresses. On 2017 January 3, a magnitude mb 4 earthquake occurred near the equatorial coast of the Maranhão State, an aseismic area of northern Brazil. Despite the few permanent stations in northern Brazil, a well-constrained strike-slip mechanism was obtained from regional moment-tensor inversion. A detailed analysis of the backazimuths of aftershocks recorded by the closest station (˜40 km away) allowed the identification of the fault plane to be the NNW-SSE trending nodal plane. An estimate of the rupture length, about 2 km, was also possible. The strike-slip mechanism has coast-parallel P axis and coast-perpendicular T axis, in agreement with most of the focal mechanisms found further to the east. The coast parallel P axis is also similar to the SHmax orientations from breakouts measurements further along the coast. The Maranhão earthquake fills an important gap of stress indicators in northern Brazil and suggests that the intraplate stress field is uniform along the 2000 km long northern coast.

  6. Provenance analysis and tectonic setting of the Neoproterozoic sediments within the Taoudeni Basin, Northern Mauritania

    Science.gov (United States)

    Nicoll, Graeme; Straathof, Gijs; Tait, Jenny; Lo, Khalidou; Ousmane, N'diaye; El Moctar Dahmada, Mohamed; Berndt, Jasper; Key, Roger

    2010-05-01

    We have dated over 800 detrital zircon grains from the Neoproterozoic sediments within the Taoudeni Basin of Mauritania on the West African craton. This sequence of sediments preserves a relatively condensed mixed continental and marine succession as well as Neoproterozoic glacial and glacially influenced deposits. The underlying Archaean and Birimian basement of the West African craton is exposed on the Reguibat shield in the north, and on the Leo shield in the south although smaller inliers occur scattered along the Bassaride and Mauritanide belts, as well as in the core of the Anti-Atlas belt. The large West African craton is totally surrounded by Pan-African fold belts. Sedimentation within the Taoudeni basin started around 1000Ma and lasted until the end of the Carboniferous. The basin is 1000-1500 km in diameter and the sedimentary pile is on average 3000 m thick. All dated zircons in the stratigraphically lowest Char and Atar Groups are older than ~1800Ma. These groups show a strong input of 2950 and 2075Ma ages, indicating sourcing from the local underlying granitic and gneissic basement. These basal sediments also include a large input from a rare 2475Ma source. Samples from the upper Assebet El Hassiane Group contain numerous zircons of 2000-900Ma. While the Neoproterozoic Marinoan glaciogenic "Triad" Jbeliat Group and stratigraphically above formations show a large range of 3200-595Ma ages. We have also undertaken a detailed Carbon isotope profile study through the carbonates which cap the Glacial Jbeliat Group. The upper part of the Jbeliat cap carbonate displays a distinct and pronounced rise from -4.3 to +3.8 13C, followed by the final demise of carbonate productivity. This positive trend is consistent with the upper part of the globally extensive Ghaub/Nantuo/Marinoan cap carbonate sequences. This world-wide sequence is characterized by composite negative-to-positive trends up section and so this isotope stratigraphy along with the zircon data helps

  7. Origin of hexavalent chromium in groundwater: The example of Sarigkiol Basin, Northern Greece.

    Science.gov (United States)

    Kazakis, N; Kantiranis, N; Kalaitzidou, K; Kaprara, E; Mitrakas, M; Frei, R; Vargemezis, G; Tsourlos, P; Zouboulis, A; Filippidis, A

    2017-09-01

    Hexavalent chromium constitutes a serious deterioration factor for the groundwater quality of several regions around the world. High concentrations of this contaminant have been also reported in the groundwater of the Sarigkiol hydrological basin (near Kozani city, NW Greece). Specific interest was paid to this particular study area due to the co-existence here of two important factors both expected to contribute to Cr(VI) presence and groundwater pollution; namely the area's exposed ophiolitic rocks and its substantial fly ash deposits originating from the local lignite burning power plant. Accordingly, detailed geochemical, mineralogical, hydro-chemical, geophysical and hydrogeological studies were performed on the rocks, soils, sediments and water resources of this basin. Cr(VI) concentrations varied in the different aquifers, with the highest concentration (up to 120μgL -1 ) recorded in the groundwater of the unconfined porous aquifer situated near the temporary fly ash disposal site. Recharge of the porous aquifer is related mainly to precipitation infiltration and occasional surface run-off. Nevertheless, a hydraulic connection between the porous and neighboring karst aquifers could not be delineated. Therefore, the presence of Cr(VI) in the groundwater of this area is thought to originate from both the ophiolitic rock weathering products in the soils, and the local leaching of Cr(VI) from the diffused fly ash located in the area surrounding the lignite power plant. This conclusion was corroborated by factor analysis, and the strongly positively fractionated Cr isotopes (δ 53 Cr up to 0.83‰) recorded in groundwater, an ash leachate, and the bulk fly ash. An anthropogenic source of Cr(VI) that possibly influences groundwater quality is especially apparent in the eastern part of the Sarigkiol basin. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Evaluation of different methods to estimate daily reference evapotranspiration in ungauged basins in Southern Brazil

    Science.gov (United States)

    Ribeiro Fontoura, Jessica; Allasia, Daniel; Herbstrith Froemming, Gabriel; Freitas Ferreira, Pedro; Tassi, Rutineia

    2016-04-01

    Evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Due to the higher information requirements of the Penman-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. This is especially important in Brazil, where the monitoring of meteorological data is precarious. In this study were compared different methods for estimating evapotranspiration for Rio Grande do Sul, the Southernmost State of Brazil, aiming to suggest alternatives to the recommended method (Penman-Monteith-FAO 56) for estimate daily reference evapotranspiration (ETo) when meteorological data is missing or not available. The input dataset included daily and hourly-observed data from conventional and automatic weather stations respectively maintained by the National Weather Institute of Brazil (INMET) from the period of 1 January 2007 to 31 January 2010. Dataset included maximum temperature (Tmax, °C), minimum temperature (Tmin, °C), mean relative humidity (%), wind speed at 2 m height (u2, m s-1), daily solar radiation (Rs, MJ m- 2) and atmospheric pressure (kPa) that were grouped at daily time-step. Was tested the Food and Agriculture Organization of the United Nations (FAO) Penman-Monteith method (PM) at its full form, against PM assuming missing several variables not normally available in Brazil in order to calculate daily reference ETo. Missing variables were estimated as suggested in FAO56 publication or from climatological means. Furthermore, PM was also compared against the following simplified empirical methods: Hargreaves-Samani, Priestley-Taylor, Mccloud, McGuiness-Bordne, Romanenko, Radiation-Temperature, Tanner-Pelton. The statistical analysis indicates that even if just Tmin and Tmax are available, it is better to use PM estimating missing variables from syntetic data than

  9. Quantitative analysis of the tectonic subsidence in the Potiguar Basin (NE Brazil)

    Science.gov (United States)

    Lopes, Juliana A. G.; de Castro, David L.; Bertotti, Giovanni

    2018-06-01

    The Potiguar Basin, located in the Brazilian Equatorial Margin, evolved from a complex rifting process implemented during the Atlantic Ocean opening in the Jurassic/Cretaceous. Different driving mechanisms were responsible for the onset of an aborted onshore rift and an offshore rift that initiated crustal rupture and the formation of a continental transform margin. Therefore, we applied the backstripping method to quantify the tectonic subsidence during the rift and post-rift phases of Potiguar Basin formation and to analyze the spatial variation of subsidence during the two successive and distinct tectonic events responsible for the basin evolution. The parameters required to apply this methodology were extracted from 2D seismic lines and exploratory well data. The tectonic subsidence curves present periods with moderate subsidence rates (up to 300 m/My), which correspond to the evolution of the onshore Potiguar Rift (∼141 to 128 Ma). From 128-118 Ma, the tectonic subsidence curves show no subsidence in the onshore Potiguar Basin, whereas subsidence occurred at high rates (over 300 m/My) in the offshore rift. The post-rift phase began ca. 118 Ma (Aptian), when the tectonic subsidence drastically slowed to less than 35 m/My, probably related to thermal relaxation. The tectonic subsidence rates in the various sectors of the Potiguar Rift, during the different rift phases, indicate that more intense faulting occurred in the southern portion of the onshore rift, along the main border faults, and in the southeastern portion of the offshore rift. During the post-rift phase, the tectonic subsidence rates increased from the onshore portion towards the offshore portion until the continental slope. The highest rates of post-rift subsidence (up to 35 m/My) are concentrated in the central region of the offshore portion and may be related to lithospheric processes related to the continental crust rupture and oceanic seafloor spreading. The variation in subsidence rates and

  10. Soil loss prediction in Guaraíra river experimental basin, Paraíba, Brazil based on two erosion simulation models

    Directory of Open Access Journals (Sweden)

    Jorge Flávio Cazé B. da Costa Silva

    2007-12-01

    Full Text Available In this study, two hydrological models to estimate soil losses and sediment yield due to sheet and channel erosion, at the basin outlet, are applied to Guaraíra River Experimental Basin, located in Paraíba State, northeastern Brazil. The soil erosion models are (a the classical Universal Soil Loss Equation (USLE, which is used to simulate annual and monthly soil losses; and (b Kineros model, which is used to simulate the sediment yield within the basin. Kineros model is a physically-based distributed model that uses a cascade of planes and channels to represent the basin and to describe the processes of interception, infiltration, surface runoff and erosion within the basin. The USLE is computed using land use, soil erodibility, topographic digital maps, as well as observed rainfall data. It was found that Guaraíra river experimental basin has a low potential for soil losses; however, specific areas which are susceptible to the erosion process in the basin could be detected by the modeling techniques coupled to a GIS (Geographic Information System.

  11. Climate and Streamflow Reconstruction on the São Francisco Basin, Brazil, Using Tree-Ring Data

    Science.gov (United States)

    Pereira, G. D. A.; Barbosa, A. C. M. C.; Granato-Souza, D.; Stahle, D. W.; Torbenson, M.; dos Santos, R. M.; Rodrigues Alves Delfino Barbosa, J. P.

    2017-12-01

    The São Francisco River crosses the most drought-prone region of Brazil and regional economic dynamics are dependent on the water availability in the basin. The seasonally dry forests are widely distributed in the basin, where Cedrela fissilis Vell (cedro) are frequently found. This semi-arid region provides a favorable setting where the deciduous cedro trees form well-defined semi-ring porous annual rings that can be exactly crossdated and used to build climate sensitive chronologies. Therefore, we have developed chronologies of cedro from seasonally dry forest fragments of three sites located in the middle-sector of the São Francisco River basin and south limit of the Brazilian Drought Polygon. The samples were analyzed according to standard procedures: sample preparation, ring count, crossdating and measurement of the tree rings. Dating quality was tested using the computer program COFECHA and ring-width time series where detrended and standardized to produce the final index chronology using the ARSTAN program. The results show that crossdating within and among trees from different sites demonstrate the potential to expand the spatial sampling. The tree-ring chronologies are sensitive with wet season precipitation totals (October - March), and can explain approximately 40% of the variance (1961-2015). Significant correlation was also observed with total annual discharge of the Rio São Francisco River measured at Barra (r=0.48; 1961-2015). However, the correlation disapears after 1993 (r=0.64 for 1961-1993, but r=-0.004 for 1994-2015) and we suspect that the stream gage at Barra has been impacted by human activity. Tree-ring chronologies can provide important information on climate and streamflow variability of São Francisco River, where hydrological records are often short and discontinuous. This chronology is now being extended with 150-yr old trees from the region and may be used to reconstruct climate and streamflow records back to the pre

  12. Water-quality assessment of the Central Arizona Basins, Arizona and northern Mexico; environmental setting and overview of water quality

    Science.gov (United States)

    Cordy, Gail E.; Rees, Julie A.; Edmonds, Robert J.; Gebler, Joseph B.; Wirt, Laurie; Gellenbeck, Dorinda J.; Anning, David W.

    1998-01-01

    The Central Arizona Basins study area in central and southern Arizona and northern Mexico is one of 60 study units that are part of the U.S. Geological Survey's National Water-Quality Assessment program. The purpose of this report is to describe the physical, chemical, and environmental characteristics that may affect water quality in the Central Arizona Basins study area and present an overview of water quality. Covering 34,700 square miles, the study area is characterized by generally north to northwestward-trending mountain ranges separated by broad, gently sloping alluvial valleys. Most of the perennial rivers and streams are in the northern part of the study area. Rivers and streams in the south are predominantly intermittent or ephemeral and flow in response to precipitation such as summer thunderstorms. Effluent-dependent streams do provide perennial flow in some reaches. The major aquifers in the study area are in the basin-fill deposits that may be as much as 12,000 feet thick. The 1990 population in the study area was about 3.45 million, and about 61 percent of the total was in Maricopa County (Phoenix and surrounding cities). Extensive population growth over the past decade has resulted in a twofold increase in urban land areas and increased municipal water use; however, agriculture remains the major water use. Seventy-three percent of all water with drawn in the study area during 1990 was used for agricultural purposes. The largest rivers in the study area-the Gila, Salt, and Verde-are perennial near their headwaters but become intermittent downstream because of impoundments and artificial diversions. As a result, the Central Arizona Basins study area is unique compared to less arid basins because the mean surface-water outflow is only 528 cubic feet per second from a total drainage area of 49,650 square miles. Peak flows in the northern part of the study area are the result of snowmelt runoff; whereas, summer thunderstorms account for the peak flows in

  13. Assessment of undiscovered conventional oil and gas resources, onshore Claiborne Group, United Statespart of the northern Gulf of Mexico Basin

    Science.gov (United States)

    Hackley, P.C.; Ewing, T.E.

    2010-01-01

    The middle Eocene Claiborne Group was assessed for undiscovered conventional hydrocarbon resources using established U.S. Geological Survey assessment methodology. This work was conducted as part of a 2007 assessment of Paleogene-Neogene strata of the northern Gulf of Mexico Basin, including the United States onshore and state waters (Dubiel et al., 2007). The assessed area is within the Upper Jurassic-CretaceousTertiary composite total petroleum system, which was defined for the assessment. Source rocks for Claiborne oil accumulations are interpreted to be organic-rich, downdip, shaley facies of the Wilcox Group and the Sparta Sand of the Claiborne Group; gas accumulations may have originated from multiple sources, including the Jurassic Smackover Formation and the Haynesville and Bossier shales, the Cretaceous Eagle Ford and Pearsall (?) formations, and the Paleogene Wilcox Group and Sparta Sand. Hydrocarbon generation in the basin started prior to deposition of Claiborne sediments and is currently ongoing. Primary reservoir sandstones in the Claiborne Group include, from oldest to youngest, the Queen City Sand, Cook Mountain Formation, Sparta Sand, Yegua Formation, and the laterally equivalent Cockfield Formation. A geologic model, supported by spatial analysis of petroleum geology data, including discovered reservoir depths, thicknesses, temperatures, porosities, permeabilities, and pressures, was used to divide the Claiborne Group into seven assessment units (AUs) with three distinctive structural and depositional settings. The three structural and depositional settings are (1) stable shelf, (2) expanded fault zone, and (3) slope and basin floor; the seven AUs are (1) lower Claiborne stable-shelf gas and oil, (2) lower Claiborne expanded fault-zone gas, (3) lower Claiborne slope and basin-floor gas, (4) lower Claiborne Cane River, (5) upper Claiborne stable-shelf gas and oil, (6) upper Claiborne expanded fault-zone gas, and (7) upper Claiborne slope and basin

  14. Hydrochemistry of the Parauari-Maues Acu river basin (Amazon region, Brazil)

    International Nuclear Information System (INIS)

    Bringel, S.R.B.

    1980-08-01

    The chemical composition of the Parauari-Maues Acu basin is studied through the determination of pH, calcium, magnesium, iron, chloride, sodium, potassium, zinc, copper and manganese. Four expeditions were made and samples were collected in 16 different points of the main course. Chemical analysis of the rivers waters shows seasonal flutuations of the concentrations of the elements in the main river as well as in the main afluents like Nambi river, Amana river and Urupadi river. (Author) [pt

  15. The Neo-Alagoas in the Ceara, Araripe and Potiguar basins (Brazil): stratigraphic and paleoecologycal caracterization

    International Nuclear Information System (INIS)

    Hashimoto, A.T.; Appi, C.J.; Soldan, A.L.; Cerqueira, J.R.

    1987-01-01

    The stratigraphic analysis of the Alagoas Stage (local stage) in Ceara Basin allows the investigated interval to be divided into two parts, with distictive tectono-sedimentary and paleobiological features. The lower part shows non-marine environmental character and the upper part, informally named Aptian-Albian transition, contains marine organisms in certain levels. These records would represent the first phases of a primitive equatorial Atlantic Ocean in the area. The Trairi Beds at the top of the continental section were deposited in an environmental complex which includes a marginal sabkha, reflecting cyclical conditions of extreme aridity or humidity. Similar events have ocurred in the Potiguar Basin with the Ponta do Tubarao Beds and in Araripe Basin with the deposition of thinny calcareous and shale layers, here informally named ''Batateria Beds''. These environmental conditions provided an excellent setting for preservation of organic matter due to cyclical anoxic processes. The observation that the organic extracts from shales of all these strata are similar supports the hypothesis of correspondence of these events. (author) [pt

  16. Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    E Bianchi

    Full Text Available Some water bodies in the Sinos River Basin (SRB have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio, using bioassays in fish and cell culture. Samples of surface water were collected and evaluated in vitro using the Astyanax jacuhiensis fish species (micronucleus test and comet assay and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT. The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio when compared to the upper section of the basin (Santo Antônio da Patrulha. The results indicate contamination by genotoxic substances starting in the middle section of the SRB.

  17. Conodont color alteration index and upper Paleozoic thermal history of the Amazonas Basin, Brazil

    Science.gov (United States)

    Cardoso, Cassiane Negreiros; Sanz-López, Javier; Blanco-Ferrera, Silvia; Lemos, Valesca Brasil; Scomazzon, Ana Karina

    2015-12-01

    The conodont color alteration index (CAI) was determined in elements from core samples of the Frasnian Barreirinha Formation (one well) and of the Pennsylvanian-Permian Tapajós Group (twenty three wells and one limestone quarry) in the Amazonas Basin. The thermal history of the basin is analyzed using the CAI value distribution represented in maps and stratigraphic sections through correlation schemes, and in conjunction with previously published data. The pattern of palaeotemperatures for CAI values of 1.5-3 is coincident with organic matter maturation under a sedimentary overburden providing diagenetic conditions in the oil/gas window. Locally, conodonts show metamorphism (CAI value of 6-7) in relation to the intrusion of diabase bodies in beds including high geothermal gradient evaporites. Microtextural alteration on the surface conodonts commonly shows several types of overgrowth microtextures developed in diagenetic conditions. Locally, recrystallization in conodonts with a high CAI value is congruent with contact metamorphism in relation to Mesozoic intrusions. The CAI values of 1.5 or 2 observed close to the surface in several areas of the basin may be interpreted in relation to a high thermal palaeogradient derived from the magmatic episode or/and to the local denudation of the upper part of the Paleozoic succession prior to this thermal event.

  18. Post-rift magmatism in the Pearl River Mouth Basin, northern South China Sea

    Science.gov (United States)

    Xu, H.; Zhao, F.; Xia, S.; Sun, J.; Fan, C.

    2017-12-01

    Multi-beam, 2D seismic reflection and borehole data reveal that post-rift magmatism are widespread in the northern margin of South China Sea. A large-scale volcanic complex was identified at water depths of 500 to 3000 m, covering an area of ca. 8000 km2. This volcanic complex includes seamounts, igneous sills, dykes and intruded volcanic bodies. Combining data from exploration wells BY7-1 and BY2 with published seismic stratigraphic data, we can highlight multiple extrusive events from the Early Oligocene to Early Miocene, reflecting progressive continental breakup in the South China Sea. Most intruded magma through the continental crust also uplifted sediments up to the T6 unconformity. Given the evidence in this work that Early Miocene magmatic bodies were developed above or along faults, we suggest that post-rift magmatism in the northern margin of the South China Sea was largely controlled by the faults. Reactivation events in the faults are suggested to have generated preferential vertical pathways for the ascent of magma within a context of progressive continental breakup and thinned continental crust, as the South China Sea was being formed.

  19. A new pale-spotted species of Hypostomus Lacépède (Siluriformes: Loricariidae from the rio Tocantins and rio Xingu basins in central Brazil

    Directory of Open Access Journals (Sweden)

    Cláudio H. Zawadzki

    Full Text Available A new species of the genus Hypostomus Lacépède (Siluriformes, Loricariidae from rio Tocantins and rio Xingu basins in central Brazil, is described. The new species is distinguished from its congeners by a unique combination of pale blotches over a darker background on head, body and fins, and conspicuous keels on head, predorsal region and lateral plates. Comments on the pale-spotted species of Hypostomus are provided.

  20. Studying Petrophysical and Geomechanical Properties of Utica Point-Pleasant Shale and its Variations Across the Northern Appalachian Basin

    Science.gov (United States)

    Raziperchikolaee, S.; Kelley, M. E.; Burchwell, A.

    2017-12-01

    Understanding petrophysical and geomechanical parameters of shale formations and their variations across the basin are necessary to optimize the design of a hydraulic fracturing program aimed at enhancing long term oil/gas production from unconventional wells. Dipole sonic logging data (compressional-wave and shear-wave slowness) from multiple wells across the study area, coupled with formation bulk density log data, were used to calculate dynamic elastic parameters, including shear modulus, bulk modulus, Poisson's ratio, and Young's modulus for the shale formations. The individual-well data were aggregated into a single histogram for each parameter to gain an understanding of the variation in the properties (including brittleness) of the Utica Point-Pleasant formations across the entire study area. A crossplot of the compressional velocity and bulk density and a crossplot between the compressional velocity, the shear velocity, and depth of the measurement were used for a high level petrophysical characterization of the Utica Point-Pleasant. Detailed interpretation of drilling induced fractures recorded in image logs, and an analysis of shear wave anisotropy using multi-receiver sonic logs were also performed. Orientation of drilling induced fractures was measured to determine the maximum horizontal stress azimuth. Also, an analysis of shear wave anisotropy to predict stress anisotropy around the wellbore was performed to determine the direction of maximum horizontal stress. Our study shows how the detailed interpretation of borehole breakouts, drilling induced fractures, and sonic wave data can be used to reduce uncertainty and produce a better hydraulic fracturing design in the Utica Point Pleasant formations across the northern Appalachian Basin region of Ohio.

  1. Hydrogeochemistry of co-occurring geogenic arsenic, fluoride and iodine in groundwater at Datong Basin, northern China

    Energy Technology Data Exchange (ETDEWEB)

    Pi, Kunfu; Wang, Yanxin, E-mail: yx.wang@cug.edu.cn; Xie, Xianjun, E-mail: xjxie@cug.edu.cn; Su, Chunli; Ma, Teng; Li, Junxia; Liu, Yaqing

    2015-12-30

    Highlights: • Co-mobilization of As, F and I was identified at Datong Basin. • Both As and I are released via reductive dissolution of Fe minerals. • Some amounts of As and I may be sequestered by FeS precipitates. • Intensive evaporation promotes retention of As but mobilization of F and I. - Abstract: Abnormal levels of co-occurring arsenic (As), fluorine (F) and iodine (I) in groundwater at Datong Basin, northern China are geochemically unique. Hydrochemical, {sup 18}O and {sup 2}H characteristics of groundwater were analyzed to elucidate their mobilization processes. Aqueous As, F and I ranged from 5.6 to 2680 μg/L, 0.40 to 3.32 mg/L and 10.1 to 186 μg/L, respectively. High As, F and I groundwater was characterized by moderately alkaline, high HCO{sub 3}{sup −}, Fe(II), HS{sup −} and DOC concentrations with H{sub 3}AsO{sub 3}, F{sup −} and I{sup −} as the dominant species. The plots of δ{sup 18}O values and Cl/Br ratios versus Cl{sup −} concentration demonstrate build-up of more oxidizing conditions and precipitation of carbonate minerals induced by vertical recharge and intensive evaporation facilitate As retention to Fe (hydr) oxides, but enhance F and I mobilization from host minerals. Under reducing conditions, As and I can be simultaneously released via reductive dissolution of Fe (hydr) oxides and reduction of As(V) and I(V) while F migration may be retarded due to effects of dissolution-precipitation equilibria between carbonate minerals and fluorite. With the prevalence of sulfate-reducing condition and lowering of HCO{sub 3}{sup −} concentration, As and I may be sequestered by Fe(II) sulfides and F is retained to fluorite and on clay mineral surfaces.

  2. Evaluation of high-resolution satellite precipitation products with surface rain gauge observations from Laohahe Basin in northern China

    Directory of Open Access Journals (Sweden)

    Shan-hu Jiang

    2010-12-01

    Full Text Available Three high-resolution satellite precipitation products, the Tropical Rainfall Measuring Mission (TRMM standard precipitation products 3B42V6 and 3B42RT and the Climate Precipitation Center's (CPC morphing technique precipitation product (CMORPH, were evaluated against surface rain gauge observations from the Laohahe Basin in northern China. Widely used statistical validation indices and categorical statistics were adopted. The evaluations were performed at multiple time scales, ranging from daily to yearly, for the years from 2003 to 2008. The results show that all three satellite precipitation products perform very well in detecting the occurrence of precipitation events, but there are some different biases in the amount of precipitation. 3B42V6, which has a bias of 21%, fits best with the surface rain gauge observations at both daily and monthly scales, while the biases of 3B42RT and CMORPH, with values of 81% and 67%, respectively, are much higher than a normal receivable threshold. The quality of the satellite precipitation products also shows monthly and yearly variation: 3B42RT has a large positive bias in the cold season from September to April, while CMORPH has a large positive bias in the warm season from May to August, and they all attained their best values in 2006 (with 10%, 50%, and −5% biases for 3B42V6, 3B42RT, and CMORPH, respectively. Our evaluation shows that, for the Laohahe Basin, 3B42V6 has the best correspondence with the surface observations, and CMORPH performs much better than 3B42RT. The large errors of 3B42RT and CMORPH remind us of the need for new improvements to satellite precipitation retrieval algorithms or feasible bias adjusting methods.

  3. Local climate change induced by groundwater overexploitation in a high Andean arid watershed, Laguna Lagunillas basin, northern Chile

    Science.gov (United States)

    Scheihing, Konstantin; Tröger, Uwe

    2018-05-01

    The Laguna Lagunillas basin in the arid Andes of northern Chile exhibits a shallow aquifer and is exposed to extreme air temperature variations from 20 to -25 °C. Between 1991 and 2012, groundwater levels in the Pampa Lagunillas aquifer fell from near-surface to 15 m below ground level (bgl) due to severe overexploitation. In the same period, local mean monthly minimum temperatures started a declining trend, dropping by 3-8 °C relative to a nearby reference station. Meanwhile, mean monthly maximum summer temperatures shifted abruptly upwards by 2.7 °C on average in around 1996. The observed air temperature downturns and upturns are in accordance with detected anomalies in land-surface temperature imagery. Two major factors may be causing the local climate change. One is related to a water-table decline below the evaporative energy potential extinction depth of 2 m bgl, which causes an up-heating of the bare soil surface and, in turn, influences the lower atmosphere. At the same time, the removal of near-surface groundwater reduces the thermal conductivity of the upper sedimentary layer, which consequently diminishes the heat exchange between the aquifer (constant heat source of 10 °C) and the lower atmosphere during nights, leading to a severe dropping of minimum air temperatures. The observed critical water-level drawdown was 2-3 m bgl. Future and existing water-production projects in arid high Andean basins with shallow groundwater should avoid a decline of near-surface groundwater below 2 m bgl and take groundwater-climate interactions into account when identifying and monitoring potential environmental impacts.

  4. Hydrogeochemistry of co-occurring geogenic arsenic, fluoride and iodine in groundwater at Datong Basin, northern China

    International Nuclear Information System (INIS)

    Pi, Kunfu; Wang, Yanxin; Xie, Xianjun; Su, Chunli; Ma, Teng; Li, Junxia; Liu, Yaqing

    2015-01-01

    Highlights: • Co-mobilization of As, F and I was identified at Datong Basin. • Both As and I are released via reductive dissolution of Fe minerals. • Some amounts of As and I may be sequestered by FeS precipitates. • Intensive evaporation promotes retention of As but mobilization of F and I. - Abstract: Abnormal levels of co-occurring arsenic (As), fluorine (F) and iodine (I) in groundwater at Datong Basin, northern China are geochemically unique. Hydrochemical, "1"8O and "2H characteristics of groundwater were analyzed to elucidate their mobilization processes. Aqueous As, F and I ranged from 5.6 to 2680 μg/L, 0.40 to 3.32 mg/L and 10.1 to 186 μg/L, respectively. High As, F and I groundwater was characterized by moderately alkaline, high HCO_3"−, Fe(II), HS"− and DOC concentrations with H_3AsO_3, F"− and I"− as the dominant species. The plots of δ"1"8O values and Cl/Br ratios versus Cl"− concentration demonstrate build-up of more oxidizing conditions and precipitation of carbonate minerals induced by vertical recharge and intensive evaporation facilitate As retention to Fe (hydr) oxides, but enhance F and I mobilization from host minerals. Under reducing conditions, As and I can be simultaneously released via reductive dissolution of Fe (hydr) oxides and reduction of As(V) and I(V) while F migration may be retarded due to effects of dissolution-precipitation equilibria between carbonate minerals and fluorite. With the prevalence of sulfate-reducing condition and lowering of HCO_3"− concentration, As and I may be sequestered by Fe(II) sulfides and F is retained to fluorite and on clay mineral surfaces.

  5. Seismic reflection-based evidence of a transfer zone between the Wagner and Consag basins: implications for defining the structural geometry of the northern Gulf of California

    Science.gov (United States)

    González-Escobar, Mario; Suárez-Vidal, Francisco; Hernández-Pérez, José Antonio; Martín-Barajas, Arturo

    2010-12-01

    This study examines the structural characteristics of the northern Gulf of California by processing and interpreting ca. 415 km of two-dimensional multi-channel seismic reflection lines (data property of Petróleos Mexicanos PEMEX) collected in the vicinity of the border between the Wagner and Consag basins. The two basins appear to be a link between the Delfín Superior Basin to the south, and the Cerro Prieto Basin to the north in the Mexicali-Imperial Valley along the Pacific-North America plate boundary. The seismic data are consistent with existing knowledge of four main structures (master faults) in the region, i.e., the Percebo, Santa María, Consag Sur, and Wagner Sur faults. The Wagner and Consag basins are delimited to the east by the Wagner Sur Fault, and to the west by the Consag Sur Fault. The Percebo Fault borders the western margin of the modern Wagner Basin depocenter, and is oriented N10°W, dipping (on average) ˜40° to the northeast. The trace of the Santa María Fault located in the Wagner Basin strikes N19°W, dipping ˜40° to the west. The Consag Sur Fault is oriented N14°W, and dips ˜42° to the east over a distance of 21 km. To the east of the study area, the Wagner Sur Fault almost parallels the Consag Sur Fault over a distance of ˜86 km, and is oriented N10°W with an average dip of 59° to the east. Moreover, the data provide new evidence that the Wagner Fault is discontinuous between the two basins, and that its structure is more complex than previously reported. A structural high separates the northern Consag Basin from the southern Wagner Basin, comprising several secondary faults oriented NE oblique to the main faults of N-S direction. These could represent a zone of accommodation, or transfer zone, where extension could be transferred from the Wagner to the Consag Basin, or vice versa. This area shows no acoustic basement and/or intrusive body, which is consistent with existing gravimetric and magnetic data for the region.

  6. Intestinal parasites in a quilombola community of the Northern State of Espírito Santo, Brazil

    Directory of Open Access Journals (Sweden)

    Schayra Minine Damazio

    2013-06-01

    Full Text Available The aim of this study was to determine the occurrence of intestinal parasites in a quilombola community from the northern Espírito Santo, Brazil. Descendants of slaves who arrived in Brazil in the sixteenth century, this population settled in the municipality of São Mateus in 1858. Fresh fecal samples from 82 individuals who agreed to participate in the study were collected between August 2009 and July 2010, and immediately sent to the Clinical Laboratory of the Centro Universitário Norte do Espírito Santo of the Universidade Federal do Espírito Santo for analysis. Out of all the participants, 36 (43.9% were male and 46 (56.1% were female, whose ages ranged from six to 85 years. The study of the occurrence of intestinal parasites indicated that 35 individuals (42.7% were infected with at least one intestinal parasite. Among helminths, the most frequent were hookworms, with a rate of 14.6%. With regard to protozoa, Entamoeba coli, Entamoeba histolytica/Entamoeba dispar and Endolimax nana stood out, with frequencies of 23.2%, 8.5% and 4.9%, respectively. The occurrence of biparasitism was observed in 13 of the 82 subjects, accounting for 15.8%, and no cases of multiple parasitic infections were observed. It was concluded that the reduction of cases of intestinal diseases due to parasites will only be achieved with the improvement of basic sanitation and quality of life of quilombola populations.

  7. Fine-grained suspended sediment source identification for the Kharaa River basin, northern Mongolia

    Science.gov (United States)

    Rode, Michael; Theuring, Philipp; Collins, Adrian L.

    2015-04-01

    Fine sediment inputs into river systems can be a major source of nutrients and heavy metals and have a strong impact on the water quality and ecosystem functions of rivers and lakes, including those in semiarid regions. However, little is known to date about the spatial distribution of sediment sources in most large scale river basins in Central Asia. Accordingly, a sediment source fingerprinting technique was used to assess the spatial sources of fine-grained (source discrimination with geochemical composite fingerprints based on a new Genetic Algorithm (GA)-driven Discriminant Function Analysis, the Kruskal-Wallis H-test and Principal Component Analysis. The composite fingerprints were subsequently used for numerical mass balance modelling with uncertainty analysis. The contributions of the individual sub-catchment spatial sediment sources varied from 6.4% (the headwater sub-catchment of Sugnugur Gol) to 36.2% (the Kharaa II sub-catchment in the middle reaches of the study basin) with the pattern generally showing higher contributions from the sub-catchments in the middle, rather than the upstream, portions of the study area. The importance of riverbank erosion was shown to increase from upstream to midstream tributaries. The source tracing procedure provides results in reasonable accordance with previous findings in the study region and demonstrates the general applicability and associated uncertainties of an approach for fine-grained sediment source investigation in large scale semi-arid catchments. The combined application of source fingerprinting and catchment modelling approaches can be used to assess whether tracing estimates are credible and in combination such approaches provide a basis for making sediment source apportionment more compelling to catchment stakeholders and managers.

  8. Penicillium excelsum sp. nov from the Brazil Nut Tree Ecosystem in the Amazon Basin'.

    Science.gov (United States)

    Taniwaki, Marta Hiromi; Pitt, John I; Iamanaka, Beatriz T; Massi, Fernanda P; Fungaro, Maria Helena P; Frisvad, Jens C

    2015-01-01

    A new Penicillium species, P. excelsum, is described here using morphological characters, extrolite and partial sequence data from the ITS, β-tubulin and calmodulin genes. It was isolated repeatedly using samples of nut shells and flowers from the brazil nut tree, Bertolletia excelsa, as well as bees and ants from the tree ecosystem in the Amazon rainforest. The species produces andrastin A, curvulic acid, penicillic acid and xanthoepocin, and has unique partial β-tubulin and calmodulin gene sequences. The holotype of P. excelsum is CCT 7772, while ITAL 7572 and IBT 31516 are cultures derived from the holotype.

  9. Norovirus diversity in diarrheic children from an African-descendant settlement in Belém, Northern Brazil.

    Directory of Open Access Journals (Sweden)

    Glicélia Cruz Aragão

    Full Text Available Norovirus (NoV, sapovirus (SaV and human astrovirus (HAstV are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola". The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA and reverse transcription-polymerase chain reaction (RT-PCR to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81, followed by SaV (2.5%-2/81 and HAstV (1.2%-1/81. Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1 and the D region of the capsid (ORF2. The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%, GII-6 (3-25%, GII-7 (2-16.7%, GII-17 (1-8.3% and GI-2 (1-8.3%, as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant, GII-6 (3-25%, GII-17 (2-16.7% and GII-20 (1-8.3%. One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20. This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.

  10. Increasing organic C and N fluxes from a northern Boreal river basin - monitoring and modelling suggest climate related controls

    Science.gov (United States)

    Lepistö, A.; Futter, M.; Kortelainen, P.

    2012-04-01

    Increasing trends in total organic carbon (TOC) concentrations in lakes and streams across northern Europe and North America have been reported. Various hypotheses including enhanced decomposition of organic soils, changes in hydrology and flow paths, decreased acid deposition and land use changes have been put forward to explain the widespread occurrence of this phenomenon. Both observational and modelling studies are needed to identify the most important drivers and relevant processes controlling observed trends in TOC concentrations. Typically, TOC concentrations in Finnish rivers and lakes are high. The Simojoki river basin (3160 km2) is located in the northern Boreal zone of Finland and experiences low, declining sulphate deposition and limited other human impacts. Forest harvest, land drainage and ditch maintenance are the main land management activities in the catchment. Long-term changes (30-40 years) and seasonal trends of total organic nitrogen (TON) and carbon (TOC) concentrations and fluxes in the Simojoki river system were studied. Concentrations of TOC and TON increased particularly during high flows. TOC concentrations are slowly but continuously increasing, fluctuating between droughts and wet periods. The highest concentrations were detected in 1998-2000 during a period of very high flows, after the drought period 1994-1997. Trends in concentrations of TOC and TON in Simojoki were not linked to declines in sulphate deposition but were more related to trends in climate and hydrology. The autumn season is particularly sensitive to climate change impacts. The INCA-C model was applied to simulate TOC dynamics in the catchment. Model results showed that climate change driven patterns in runoff and soil moisture and soil temperature were more important than temporal patterns of sulphate deposition and land management in controlling surface water TOC concentrations. The possible factors behind changes of TOC and TON concentrations and increasing fluxes to

  11. The evolution of Neoproterozoic magmatism in Southernmost Brazil: shoshonitic, high-K tholeiitic and silica-saturated, sodic alkaline volcanism in post-collisional basins

    Directory of Open Access Journals (Sweden)

    Sommer Carlos A.

    2006-01-01

    Full Text Available The Neoproterozoic shoshonitic and mildly alkaline bimodal volcanism of Southernmost Brazil is represented by rock assemblages associated to sedimentary successions, deposited in strike-slip basins formed at the post-collisional stages of the Brasilian/Pan-African orogenic cycle. The best-preserved volcano sedimentary associations occur in the Camaquã and Campo Alegre Basins, respectively in the Sul-riograndense and Catarinense Shields and are outside the main shear belts or overlying the unaffected basement areas. These basins are characterized by alternation of volcanic cycles and siliciclastic sedimentation developed dominantly on a continental setting under subaerial conditions. This volcanism and the coeval plutonism evolved from high-K tholeiitic and calc-alkaline to shoshonitic and ended with a silica-saturated sodic alkaline magmatism, and its evolution were developed during at least 60 Ma. The compositional variation and evolution of post-collisional magmatism in southern Brazil are interpreted as the result mainly of melting of a heterogeneous mantle source, which includes garnet-phlogopite-bearing peridotites, veined-peridotites with abundant hydrated phases, such as amphibole, apatite and phlogopite, and eventually with the addition of an asthenospheric component. The subduction-related metasomatic character of post-collisional magmatism mantle sources in southern Brazil is put in evidence by Nb-negative anomalies and isotope features typical of EM1 sources.

  12. Chemical elements in soils of riverside areas of the Piracicaba river basin, São Paulo, Brazil

    International Nuclear Information System (INIS)

    França, Elvis J.; Lira, Marcelo B.G.; Paiva, José D.S.; Fernandes, Elisabete A. de N.; Fonseca, Felipe Y.; Rodrigues, Vanessa S.; Cavalca, Isabel P.O.; Camilli, Leandro

    2017-01-01

    The monitoring of the soil quality of the Piracicaba River Basin, located in the State of São Paulo, is of extreme environmental importance, as it ensures the functionality of the basin ecosystems and environmental protection. However, there are few studies focused on the concentration of chemical elements in soils of environmental protection zones of highly populated riverside regions. In view of the above, this work aims to determine the concentration of chemical elements in the soils located on the banks of the Piracicaba River by the Instrumental Neutronic Activation Analysis - INAA. Soil samples were collected in the 0-5 cm, 5-10 cm and 10-15 cm profiles. Subsequently, the samples were dried in an oven at 80 deg C and comminuted with the aid of mortar and pistil. 250 mg portions were transferred to polyethylene capsules and irradiated in 10 13 cm -2 .s -1 neutron flux for 4 hours at the IEA-R1 Nuclear Research Reactor of the Nuclear and Energy Research Institute -IPEN / SP, Brazil. The determination of the chemical elements was conducted by the k0-INAA method from the Quantu program. Comparing the results obtained with the soil values of an untouched area of Atlantic Forest - Carlos Botelho State Park, the maximum values obtained of As (29 mg / kg) and Zn (185 mg / kg) were about 5 times greater. However, concentrations of terrigenous elements such as Fe and Sc were also high in some cases, indicating that there is also a contribution of the source material (rocks) to the high concentrations observed in the riverside soils

  13. Occurrence, behavior and distribution of high levels of uranium in shallow groundwater at Datong basin, northern China

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ya; Wang, Yanxin, E-mail: yx.wang@cug.edu.cn; Xie, Xianjun

    2014-02-01

    Geochemical investigations of uranium (U) occurrence in the environments were conducted at Datong basin of northern China. The results suggest that U contents were generally < 1 mg/kg for the igneous and metamorphic rocks, typically 2–5 mg/kg for the Carboniferous and Permian sedimentary rocks and around 3 mg/kg for sediments and topsoil, respectively. U in the Quaternary aquifer sediments may be primarily associated with carnotite from the Carboniferous and Permian coal-bearing clastic rocks around the basin. Shallow groundwater had U concentrations of < 0.02–288 μg/L (average 24 μg/L), with 24% of the investigated boreholes above the WHO provisional guideline of 30 μg/L for U in drinking water. Average U concentration for surface water was 5.8 μg/L. In oxidizing waters, uranyl (UO{sub 2}{sup 2+}) species is dominant and strongly adsorbed onto iron (hydro)xides, while it would be preferentially complexed with carbonate in the alkaline groundwater, forming highly soluble uranyl-carbonate complexes at Datong. Under reducing conditions, uranous (U(IV)) species is ready to precipitate or bind to organic matter, therefore having a low mobility. At the study area, high U groundwater (> 30 μg/L) occurs at the alluvial plains due to intermediate redox and enhanced alkaline conditions. The abnormally high levels of U in groundwater (> 100 μg/L) are locally found at the west alluvial plains. By contrast, U co-precipitation with secondary carbonate minerals like Ca{sub 2}UO{sub 2}(CO{sub 3}){sub 3} in the dominant Ca–Mg–Na–HCO{sub 3} type groundwater may prevail at the east alluvial plains. Besides, bedrocks such as Carboniferous and Permian sedimentary rocks, especially the coal-bearing strata which have higher U contents at the west mountain areas may also account for the abnormally high levels of U in groundwater. - Highlights: • High U groundwater occurs at the alluvial plains of Datong basin. • Redox state, complexation and adsorption are responsible

  14. Morphology, sedimentary features and evolution of a large palaeo submarine canyon in Qiongdongnan basin, Northern South China Sea

    Science.gov (United States)

    Li, Xiangquan; Fairweather, Luke; Wu, Shiguo; Ren, Jianye; Zhang, Hongjie; Quan, Xiayun; Jiang, Tao; Zhang, Cheng; Su, Ming; He, Yunlong; Wang, Dawei

    2013-01-01

    The large Miocene-aged palaeo canyon that extents through the Qiongdongnan basin (QDNB) and Yinggehai basin (YGHB) of Northern South China Sea has been of considerable interest both economically and scientifically over the past decade. Stemmed from this, significant research has been employed into understanding the mechanism for its existence, incision, and sedimentary fill, yet debate remains. In the first case the canyon itself is actually quite anomalous. Alone from the size (over 570 km in length and more than 8 km in width (Yuan et al., 2009)), which is considerably more than most ancient deep-water channels (REFS), the canyon's sedimentary fill is also distinctly different. Some explanations have been given to explain the canyon's origin and existence, these include increased sediment supply from the Red River which is genetically linked to uplift of the Tibetan Plateau, lowstand turbidite and mass-transport activity, reactivation and dextral displacement of the Red River Fault zone inducing erosive gravity-flows, regional tilt of the QDNB and YGHB, paleo-seafloor morphology and seal-level fluctuations. With the application of new data obtained from interpretations of a large number of 2D seismic profiles, core and well log data, and tectonic and sedimentary analysis this contribution aims to: (1) Present models to explain the Canyon's sedimentary fill and basin plain deposits, which provided significant understanding of processes pre-, syn- and post-incision and; (2) review the plausibility and likelihood of each of the controlling mechanisms, hoping to shed light on this controversial aspect. We conclude that the final erosive event that shaped the canyon is dated at 5.5 Ma. The Canyon's unusual fill is a product of variation in the interaction between turbidity currents and MTD that blocked the canyon's axis, and the reduction in gravity flow energy through time; and therefore the complete succession represents one major erosive and cut event at 5.5 Ma and

  15. Did Oligocene crustal thickening precede basin development in northern Thailand? A geochronological reassessment of Doi Inthanon and Doi Suthep

    Science.gov (United States)

    Gardiner, Nicholas J.; Roberts, Nick M. W.; Morley, Christopher K.; Searle, Michael P.; Whitehouse, Martin J.

    2016-01-01

    The Doi Inthanon and Doi Suthep metamorphic core complexes in northern Thailand are comprised of amphibolite-grade migmatitic gneisses mantled by lower-grade mylonites and metasedimentary sequences, thought to represent Cordilleran-style core complexes exhumed through the mobilization of a low-angle detachment fault. Previous studies have interpreted two metamorphic events (Late Triassic and Late Cretaceous), followed by ductile extension between the late Eocene and late Oligocene, a model which infers movement on the detachment at ca. 40 Ma, and which culminates in a rapid unroofing of the complexes in the early Miocene. The Chiang Mai Basin, the largest such Cenozoic Basin in the region, lies immediately to the east. Its development is related to the extension observed at Doi Inthanon and Doi Suthep, however it is not definitively dated, and models for its development have difficulty reconciling Miocene cooling ages with Eocene detachment movement. Here we present new in-situ LA-ICP-MS and SIMS U-Pb age data of zircon and monazite grains from gneiss and leucogranite samples taken from Doi Inthanon and Doi Suthep. Our new zircon data exhibit an older age range of 221-210 Ma, with younger ages of ca. 72 Ma, and 32-26 Ma. Our monazite data imply an older age cluster at 83-67 Ma, and a younger age cluster of 34-24 Ma. While our data support the view of Indosinian basement being reworked in the Cretaceous, they also indicate a late Eocene-Oligocene tectonothermal event, resulting in prograde metamorphism and anatexis. We suggest that this later event is related to localized transpressional thickening associated with sinistral movement on the Mae Ping Fault, coupled with thickening at the restraining bend of the Mae Yuan Fault to the immediate west of Doi Inthanon. Further, this upper Oligocene age limit from our zircon and monazite data would imply a younger Miocene constraint on movement of the detachment, which, when combined with the previously recorded Miocene

  16. Environmental pollution in Piracicaba Basin, Minas Gerais state, 'steel valley', Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Marluce Teixeira Andrade; Veado, Maria Adelaide R.V. [Centro Universitario do Leste de Minas Gerais (UNILESTE-MG), Coronel Fabriciano, MG (Brazil)]. E-mails: mariavasc@unilestemg.br; marluce.queiroz@yahoo.com.br; Menezes, Maria Angela de B.C.; Amaral, Maria Angela [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: menezes@cdtn.br

    2007-07-01

    Total heavy metal and trace elements concentrations were evaluated in smelting waste areas, in Piracicaba River, Minas Gerais, Brazil. The studies samples were surface water, border sediment, and fish muscle (Acara - Geophagus Brasiliensis). Elevated concentrations were found in Acara muscle fish As (1.3 - 1.8 {mu}g g{sup -1}), Hg (0.7 - 1.84 {mu}g g{sup -1}), Cr (0.7 - 4.1 {mu}g g{sup -1}), Zn ( 43 - 76 {mu}g g{sup -1}); in sediment Fe (81996 - 461147 {mu}g g{sup -1}), Cr (126 - 447 {mu}g g{sup -1}), Co ( 540 - 1016 {mu}g g{sup -1}), Th (7.9 - 50 {mu}g g{sup -1}). For the water samples the similar high heavy metal concentrations of Al, As, Cr, Fe, and Zn in all sampling sites were above the maximum limits permitted by Brazilian Environmental Council. The high level of heavy metals can affect the aquatic and cattle animals and human health. To conclusion the region studied in Piracicaba River in Minas Gerais State, Brazil, is not in agreement with the environmental parameters for 'water class 3' according to Resolution by Brazilian Environmental Standards (CONAMA). An urgent program of measures for assessment and monitoring is necessary in this River. (author)

  17. Pockmark asymmetry and seafloor currents in the Santos Basin offshore Brazil

    Science.gov (United States)

    Schattner, U.; Lazar, M.; Souza, L. A. P.; ten Brink, Uri S.; Mahiques, M. M.

    2016-01-01

    Pockmarks form by gas/fluid expulsion into the ocean and are preserved under conditions of negligible sedimentation. Ideally, they are circular at the seafloor and symmetrical in profile. Elliptical pockmarks are more enigmatic. They are associated with seafloor currents while asymmetry is connected to sedimentation patterns. This study examines these associations through morphological analysis of new multibeam data collected across the Santos continental slope offshore Brazil in 2011 (353–865 mbsl). Of 984 pockmarks, 78% are both elliptical and asymmetric. Geometric criteria divide the pockmarks into three depth ranges that correlate with a transition between two currents: the Brazil Current transfers Tropical Water and South Atlantic Central Water southwestwards while the Intermediate Western Boundary Current transfers Antarctic Intermediate Water northeastwards. It is suggested that the velocity of seafloor currents and their persistence dictate pockmark ellipticity, orientation and profile asymmetry. Fast currents (>20 cm/s) are capable of maintaining pockmark flank steepness close to the angle of repose. These morphological expressions present direct evidence for an edge effect of the South Atlantic Subtropical Gyre and, in general, provide a correlation between pockmark geometry and seafloor currents that can be applied at other locations worldwide.

  18. Soil erosion determination in an watershed from Northern Parana (Brazil) using 137Cs

    International Nuclear Information System (INIS)

    Andrello, Avacir Casanova; Appoloni, Carlos Roberto; Guimaraes, Maria de Fatima

    2004-01-01

    The objective of this work was study the soil losses or gains in a watershed in the municipal district of Ca mbe, P R, Brazil using 137 Cs as marker for the determination of soil redistributions. A transect sampling was used to evaluate the influence of different tillage on soil erosion. One point, located in a forest area was sampled and analyzed to determine the reference inventory of cesium-137 deposited by fallout. The average value of the reference inventory was 292 Bq m -2 . The cesium-137 inventory of the transect samples varied from 80 Bq m -2 to 403 Bq m -2 . The sampling points in pasture presented soil losses. The sampling points in coffee plantation did not present losses or gains. The sampling points in soybean cultivated areas presented soil losses. (author)

  19. Evidence for the co-circulation of dengue virus type 3 genotypes III and V in the Northern region of Brazil during the 2002-2004 epidemics

    Directory of Open Access Journals (Sweden)

    Meri Bordignon Nogueira

    2008-08-01

    Full Text Available The reintroduction of dengue virus type 3 (DENV-3 in Brazil in 2000 and its subsequent spread throughout the country was associated with genotype III viruses, the only DENV-3 genotype isolated in Brazil prior to 2002. We report here the co-circulation of two different DENV-3 genotypes in patients living in the Northern region of Brazil during the 2002-2004 epidemics. Complete genomic sequences of viral RNA were determined from these epidemics, and viruses belonging to genotypes V (Southeast Asia/South Pacific and III were identified. This recent co-circulation of different DENV-3 genotypes in South America may have implications for pathological and epidemiological dynamics.

  20. Results of the marine biota monitoring during drilling activity on Campos Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Petta, Claudia Brigagao de; Bastos, Fabio; Danielski, Monica; Ferreira, Mariana; Gama, Mariana; Coelho, Ana Paula Athanazio; Maia, Decio [Aecom do Brasil Ltda, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    The Environmental Monitoring Project (PMA) aims to report environmental changes arising from drilling activity, in relation to the marine fauna. This project can also help in the monitoring of accidental spills. Since the professionals spend six hours of the day monitoring the ocean around the rigs, they can locate and identify oil stains, notify the responsible onboard, and also help in the monitoring of the oil stain. Such Project has been developed onboard a drilling unit working in Campos Basin. The results presented here were collected during the drilling activity in Bijupira and Salema fields, by Shell Brasil Petroleo Ltda, from July 13th to October 8th, 2011.

  1. Soil gamma ray spectrometry of the Buquira river basin, SP, Brazil

    International Nuclear Information System (INIS)

    Rivera, Alice

    2002-12-01

    Natural radioactivity found in rocks and its evaluation been frequently used for studies of environmental geochemistry, particularly those of detection and control of pollutants and the consequent changes in environment after antropic interferences. In this work natural radioactivity in forty nine soil samples in the basin of Buquira river, at the Northeast region of Sao Paulo State, has been analysed and measured with a Ge-HP gamma ray spectrometer. A table with the most relevant results found in rocks is shown and discussed. (author)

  2. Freshwater gastropods in the Northern littoral mesoregion of Espírito Santo, Brazil

    Directory of Open Access Journals (Sweden)

    Marco Antônio Andrade de Souza

    2017-09-01

    Full Text Available Studies on the distribution of molluscs in Brazilhave been conducted since the beginning of the twentieth and the knowledge of the species distributed in the country represent important findings, which contribute to the understanding of human diseases and those of veterinary importance, transmitted by them. In order to verify the distribution of freshwater gastropods in Espírito Santo, a malacological surveywas carried out in nine municipalities that comprise the Northern mesoregion of the State, between January 2010 and February 2015. Initially the water collections occurring in the municipality were verified and the lotic systems at different levels of use and conservation were determined. Molluscs were collected monthly using a hand net adapted to a stick steel. An individual sample effort of 30 minutes was applied, by scanning, at about ten meters in each one of the selected habitats. A total of 6,000 specimens were collected, represented by genera Melanoides, Drepanotrema, Physa, Biomphalaria and Pomacea. Among the molluscs, some specimens were positive for flatworm larvae of medical and veterinary importance. The results contributed to the knowledge of the current distribution of freshwater gastropods in the Northern region of Espírito Santo whose the only record for the region dates back to 1983.

  3. Chemical, mineralogical and ceramic properties of clays from Northern Santa Catarina, Brazil

    International Nuclear Information System (INIS)

    Correia, S.L.; Bloot, E.L.; Folgueras, M.V.; Hotza, D.

    2009-01-01

    Clay materials crop out in the northern Santa Catarina mining district were investigated in order to assess their potential in the ceramic industry. Four different clays (A, B, C and D) were selected. Their chemical composition was obtained by Xray fluorescence and their mineralogy by X-ray diffraction, coupled with numerical rational analysis. Their thermal behaviour was studied by differential thermal analysis. Technological testing consisted in a simulation of the industrial processing performed at a laboratory scale. The test pieces were obtained by pressing and fired in the range of 850-1200 deg C. In each case their technological properties were studied. The main mineralogical phases detected were kaolinite, quartz and mica. Hematite and feldspars may be present in the clays. The clays show two groups of particle sizes almost equally frequent in the range of 1 to 60 μm. The northern Santa Catarina clays are suitable for the production of bricks and earthenware in the 900- 1100 deg C range. (author)

  4. (Plio-)Pleistocene alluvial-lacustrine basin infill evolution in a strike-slip active zone (Northern Andes, Western-Central Cordilleras, Colombia)

    OpenAIRE

    SUTER, F.; NEUWERTH, R.; GORIN, G.; GUZMÁN, C.

    2009-01-01

    The (Plio)-Pleistocene Zarzal Formation was deposited in the Cauca Depression and Quindío-Risaralda Basin between the Western and Central Cordilleras (Northern Andes). This area is structurally located on the transcurrent Romeral Fault System (RFS). Because of the interaction between the Nazca plate and the Chocó-Panamá block (an active indenter), the RFS strike-slip component changes direction around the study zone (dextral in the south, senestral in the north). Zarzal sediments are the olde...

  5. Growth of the Zagros Fold-Thrust Belt and Foreland Basin, Northern Iraq, Kurdistan

    Science.gov (United States)

    Koshnaw, Renas; Horton, Brian; Stockli, Daniel; Barber, Douglas; Ghalib, Hafidh; Dara, Rebwar

    2016-04-01

    The Zagros orogenic belt in the Middle Eastern segment of the Alpine-Himalayan system is among the youngest seismically active continental collision zones on Earth. However, due to diachronous and incremental collision, the precise ages and kinematics of shortening and deposition remain poorly understood. The Kurdistan region of the Zagros fold-thrust belt and foreland basin contains well-preserved Neogene wedge-top and foredeep deposits that include clastic nonmarine fill of the Upper Fars, Lower Bakhtiari, and Upper Bakhtiari Formations. These deposits record significant information about orogenic growth, fold-thrust dynamics, and advance of the deformation front. Thermochronologic and geochronologic data from thrust sheets and stratigraphic archives combined with local earthquake data provide a unique opportunity to address the linkages between surface and subsurface geologic relationships. This research seeks to constrain the timing and geometry of exhumation and deformation by addressing two key questions: (1) Did the northwestern Zagros fold-thrust belt evolve from initial thin-skinned shortening to later thick-skinned deformation or vice-versa? (2) Did the fold-thrust belt advance steadily under critical/supercritical wedge conditions involving in-sequence thrusting or propagate intermittently under subcritical conditions with out-of-sequence deformation? From north to south, apatite (U-Th)/He ages from the Main Zagros Thrust, the Mountain Front Flexure (MFF), and additional frontal thrusts suggest rapid exhumation by ~10 Ma, ~5 Ma, and ~8 Ma respectively. Field observations and seismic sections indicate progressive tilting and development of growth strata within the Lower Bakhtiari Formation adjacent to the frontal thrusts and within the Upper Bakhtiari Formation near the MFF. In the Kurdistan region of Iraq, a regional balanced cross section constrained by new thermochronometric results, proprietary seismic reflection profiles, and earthquake hypocenters

  6. Role of sulfur redox cycling on arsenic mobilization in aquifers of Datong Basin, northern China

    International Nuclear Information System (INIS)

    Pi, Kunfu; Wang, Yanxin; Xie, Xianjun; Ma, Teng; Su, Chunli; Liu, Yaqing

    2017-01-01

    Sulfur redox cycling potentially exerts important influences on arsenic (As) fate in shallow groundwater systems. Hydrochemical and sediment geochemical analysis combined with thermodynamic modeling study were conducted at Datong Basin to elaborate the effects of sulfur redox cycling on As speciation and mobilization under a strongly reducing environment. Dissolved As and sulfide concentration in 32 groundwater samples with depths of 19–40 m below the land surface varied from 8 to 2700 μg/L and from <5 to 490 μg/L, respectively, while dissolved Fe(II) was relatively low ranging from <20 to 280 μg/L. The apparent co-increase in dissolved sulfide and As concentration, especially for samples with As content larger than 500 μg/L, indicates that sulfidogenesis may significantly contribute to the mobilization of As via sulfide-induced reduction of both As-bearing Fe(III) oxide minerals and As(V). Thermodynamic calculations indicate that groundwater As might be also thiolated in the presence of high-level sulfide, particularly to a large extent for As(V) speciation, instead of sequestration by As-sulfide precipitates. Results of sequential extraction and scanning electron microscopy array on sediments indicate the presence of Fe(II) sulfide mineral phases and an appreciable amount of co-existent As in the sediments, suggesting the precipitation of Fe(II) sulfides can restrict the build-up of dissolved Fe(II) and sequester As from groundwater, but not strongly enough, thereby lowering down As to a moderate level of about 500 μg/L. Thus, redox processes involving As, S and Fe species under sulfidic conditions as observed in Datong Basin not only facilitate the enrichment of As(III) species and As(V) potentially existing as thiolated species, but also the depletion of Fe(II) concentration in groundwater due to Fe(II) sulfide formation. - Highlights: • Effects of sulfur redox cycling on As enrichment were clarified in Datong. • Co-increase in aqueous As and

  7. Crustal structure of an exhumed IntraCONtinental Sag (ICONS): the Mekele Basin in Northern Ethiopia.

    Science.gov (United States)

    Alemu, T. B.; Abdelsalam, M. G.

    2017-12-01

    The Mekele Sedimentary Basin (MSB) in Ethiopia is a Paleozoic-Mesozoic IntraCONtinental Sag (ICONS) exposed due to Cenozoic domal and rift flank uplift associated with the Afar mantle plume and Afar Depression (AD). ICONS are formed over stable lithosphere, and in contrast to rift and foreland basins, show circular-elliptical shape in map view, saucer shaped in cross section, and concentric gravity minima. Surface geological features of the MSB have been shown to exhibit geologic characteristics similar to those of other ICONS. We used the World Gravity Map (WGM 2012) data to investigate subsurface-crustal structure of the MSB. We also used 2D power spectrum analysis and inversion of the gravity field to estimate the Moho depth. Our results show the Bouguer anomalies of the WGM 2012 ranges between 130 mGal and - 110 mGal with the highest values within the AD. Despite the effect of the AD on the gravity anomalies, the MSB is characterized by the presence of gravity low anomaly that reaches in places -110 mGal, especially in its western part. The Moho depth estimates, from both spectral analysis and inversion of the gravity data, is between 36 and 40 km depth over most of the western and southern margins of the MSB. However, as the AD is approached, in the eastern margins of the MSB, crustal thickness estimates are highly affected by the anomalously thin and magmatic segment of the AD, and the Moho depth range between 30 and 25 km. Our results are consistent with that of seismic studies in areas far from the MSB, but within the Northwestern Ethiopian Plateau where the MSB is located. Those studies have reported an abrupt decrease in Moho depth from 40 km beneath the Northwestern plateau, to 20 km in the adjacent AD. Though the MSB is small (100 kmX100 km) compared to other ICONS, and affected by the neighboring AD, it is characterized by elliptical gravity minima and a relatively thicker crust that gradually thickens away from the rift. In addition, seismic imaging

  8. Urbanization and runoff in the Tucunduba hydrographic basin, Belém, PA, Brazil

    Directory of Open Access Journals (Sweden)

    Nelson Wellausen Dias

    2012-08-01

    Full Text Available The present work investigated the runoff resulting from urban sprawl in the area of Tucunduba basin, in Belem, in the period between 1972 and 2006, which is characterized by a urbanization process started in the 1960s by low income population without adequate infrastructure services. Urbanization modifies the soil surface interfering on the ground phase of the hydrological cycle, inasmuch as it reduces the area of infiltration, increases runoff, and the runoff coefficient. A geographic database with land use and land cover map layers extracted from orthophotos acquired in 1972, 1977, and 1998 and a SPOT satellite image acquired in 2006 were used. Digital maps and analysis of the urbanization processes were supported by tools available in ArcGIS™ software package. To estimate the infiltration potential (S and effective rainfall (Pe, as a function of rainfall duration equal to the maximum time of concentration of the water in the basin, Curve Number methodology proposed by the Natural Resources Conservation Service (NRCS was applied. Rainfall estimates were calculated using the maximum rain equation for the city of Belém, with return times specified at 2, 5, 10, 15, 20, 25, 50, 100, and 200 years. The results showed an increase in areas of high and medium population density (urban and reduced area of low population density (secondary forest growth for the years of 1972, 1977, 1998, and 2006, that generated a higher effective precipitation value and, therefore, a higher effective runoff coefficient value (C.

  9. DEVELOPING SUSTAINABILITY INDICATORS FOR WATER RESOURCES MANAGEMENT IN TIETÊ-JACARÉ BASIN, BRAZIL

    Directory of Open Access Journals (Sweden)

    Michele de Almeida Corrêa

    2013-06-01

    Full Text Available This paper describes a tool to assist in developing water resources management, focusing on the sustainability concept, by a Basin Committee. This tool consists of a Set of Sustainability Indicators for Water Resources Management denominated CISGRH, which was identified by a conceptual and empirical review to meet the specific needs of the study herein - the Basin Committee of Tietê-Jacaré Rivers (CBH-TJ. The framework of CISGRH came about through consecutive consultation processes. In the first consultation the priority problems were identified for the study objectives, listing some possible management sustainability indicators. These preliminary indicators were also submitted to academic specialists and technicians working in CBH-TJ for a new consultation process. After these consultation stages, the CISGRH analysis and structuring were introduced. To verify the indicators’ adaptation and to compose a group as proposed by the study, these were classified according to specific sustainability principles for water resources management. The objective of the CISGRH implementation is to diagnose current conditions of water resources and its management, as well as to evaluate future conditions evidenced by tendencies and interventions undertaken by the committee.

  10. DEVELOPING SUSTAINABILITY INDICATORS FOR WATER RESOURCES MANAGEMENT IN TIETÊ-JACARÉ BASIN, BRAZIL

    Directory of Open Access Journals (Sweden)

    Michele de Almeida Corrêa

    2013-01-01

    Full Text Available This paper describes a tool to assist in developing water resources management, focusing on the sustainability concept, by a Basin Committee. This tool consists of a set of sustainability indicators for water resources management denominated CISGRH, which was identified by a conceptual and empirical review to meet the specific needs of the study herein - the basin committee of Tietê-J acaré Rivers (CBH-TJ. The framework of CISGRH came about through consecutive consultation processes. In the first consultation, the priority problems were identified for the study objectives, listing some possible management sustainability indicators. These preliminary indicators were also submitted to academic specialists and technicians working in CBH-TJ for a new consultation process. After these consultation stages, the CISGRH analysis and structuring were introduced. To verify the indicators’ adaptation and to compose a group as proposed by the study, these were classified according to specific sustainability principles for water resources management. The objective of the CISGRH implementation is to diagnose current conditions of water resources and its management, as well as to evaluate future conditions evidenced by tendencies and interventions undertaken by the committee.

  11. Biodiversity and community structure of zooplankton in the Sub-basin of Rio Poxim, Sergipe, Brazil

    Directory of Open Access Journals (Sweden)

    Eliane Maria de Souza Nogueira

    2011-08-01

    Full Text Available The zooplankton of aquatic environments is composed mostly of protozoans, rotifers, cladocerans and copepods, which play an important role in the food chain, transferring mass and energy from primary producers to higher trophic levels. This work was prepared with the objective of contributing to the knowledge of zooplankton biodiversity that occurs in the Sub-basin of Rio Poxim. Water samples were taken at monthly intervals at four sampling stations located along the sub-basin in the period August 2009 to July 2010. To obtain the zooplankton community, 100 L of water were filtered on nylon net with an aperture of 50 mm. Were identified 72 taxa distributed in the following taxonomic categories Rotifera, Protozoa, Porifera, Nematoda, Anellida, Cladocera, Copepoda, Ostracoda, Isopoda and Insecta. In terms of species richness, the phylum Rotifera followed by the Protoctista were the most relevant with forty and fifteen taxa, respectively. The most representative taxa in numerical terms were Arcella vulgaris, Notholca sp. Rotary sp. and nematodes. Regarding the community diversity index, the community was characterized as low diversity, but the taxa were distributed evenly in all monitoring points.

  12. Cytogenetic analysis in Thoracocharax stellatus (Kner, 1858 (Characiformes, Gasteropelecidae from Paraguay River Basin, Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Edson Silva

    2012-09-01

    Full Text Available Thoracocharax stellatus (Characiformes, Gasteropelecidae is a small Neotropical species of fish, widely distributed in several rivers of South America. Evidence for karyotype heteromorphysm in populations from different geographical regions has been reported for this species. In this way, populations of T. stellatus from the Paraguay River basin were cytogenetically characterized and the results were compared with other studies performed in the same species but from different basins. The results showed a diploid number of 2n = 54 for T. stellatus, with chromosomes arranged in 6 metacentric (m, 6 submetacentric (sm, 2 subtelocentric (st and 40 acrocentric (a, for both sexes, with a simple Nucleolus Organiser Region (NOR system reported by the techniques of silver nitrate impregnation and fluorescent in situ hybridisation (FISH using 18S rDNA sequences as probe. The distribution of constitutive heterochromatin, observed by the C-band technique and Chromomycin A3 staining showed great similarity among the analyzed populations and consists mainly of discrete blocks in the pericentromeric and telomeric regions of most chromosomes. The presence of female heterogamety was also observed indicating a ZZ/ZW system with W chromosome almost totally heterochromatic. The results also show cytogenetic diversity of the group and are useful to understand the mechanisms of karyotype evolution of the family.

  13. A new species of Hisonotus (Siluriformes, Loricariidae from rio São Francisco basin, Brazil

    Directory of Open Access Journals (Sweden)

    Fábio Roxo

    2015-04-01

    Full Text Available A new species of Hisonotus is described from the rio São Francisco basin. The new species can be distinguished from congeners by having (1 a unique coloration pattern of caudal fin with one black spot extending from its origin to the ventral lobe and two dark spots at the end of the lobe’s rays; (2 odontodes forming longitudinally aligned rows on head and trunk; (3 a functional V-shaped spinelet; (4 a single rostral plate at the tip of the snout; (5 by lacking contrasting dark geometric spots on the anterodorsal region of the body; (6 a lower caudal-peduncle depth; and (7 lower counts of the lateral median plates and (8 higher premaxillary and dentary teeth. The new species is the second described species of the genus Hisonotus in the rio São Francisco basin. It was found inhabiting the marginal vegetation of the rio São Francisco and three of its tributary, rio das Velhas, rio Paraopeba and rio Formoso.

  14. Stable isotope record of Eemian seasonal temperature from MIS 5e tufa stromatolite; Somme Basin, Northern France

    Science.gov (United States)

    Dabkowski, J.; Andrews, J.; Antoine, P.; Marca-Bell, A.

    2013-03-01

    In many modern to sub-fossil deposits tufa formations, very well crystallised deposits called stromatolites are preserved. These are often strongly laminated deposits, the laminae linked to seasonal climatic and environmental variations. Where found in fossil tufas such deposits have huge potential as high resolution archives of Pleistocene climate. One of the first investigations of this type has been performed on a 2.5 cm-radius stromatolite from the Eemian sequence of Caours (Somme Basin, Northern France), where precise observations in thin section have been combined with intra-lamina δ18O and δ13C analyses. Independent interpretations of petrographical and geochemical data are strongly coherent and demonstrate a clear seasonal signal. Moreover, as δ18O is temperature dependent, we have quantified likely maximum water temperature variations between summer and winter at Caours. A small mismatch between the δ18O derived temperature values and the typical modern range is observed, which may reflect a real difference between modern and Eemian temperature seasonality. This study supports previous investigations performed on a laminated tufa from central Greece and clearly confirms the potential of tufa stromatolites as records of seasonal climatic information and for the quantification of riverine water temperature variations.

  15. Geohydrology of the northern Louisiana salt-dome basin pertinent to the storage of radioactive wastes; a progress report

    Science.gov (United States)

    Hosman, R.L.

    1978-01-01

    Salt domes in northern Louisiana are being considered as possible storage sites for nuclear wastes. The domes are in an area that received regional sedimentation through early Tertiary (Eocene) time with lesser amounts of Quaternary deposits. The Cretaceous-Tertiary accumulation is a few thousand feet thick; the major sands are regional aquifers that extend far beyond the boundaries of the salt-dome basin. Because of multiple aquifers, structural deformation, and variations in the hydraulic characteristics of cap rock, the ground-water hydrology around a salt dome may be highly complex. The Sparta Sand is the most productive and heavily used regional aquifer. It is either penetrated by or overlies most of the domes. A fluid entering the Sparta flow system would move toward one of the pumping centers, all at or near municipalities that pump from the Sparta. Movement could be toward surface drainage where local geologic and hydrologic conditions permit leakage to the surface or to a surficial aquifer. (Woodard-USGS)

  16. Late Quaternary evolution of the Rotoaira Basin, northern Tongariro ring plain, New Zealand

    International Nuclear Information System (INIS)

    Lecointre, J.A.; Neall, V.E.; Wallace, R.C.; Elliot, M.B.; Sparks, R.J.

    2004-01-01

    The last 100,000 yr record of volcaniclastic sedimentation in the Rotoaira Basin reflects the critical role played by tectonic and eruptive activity that led to: (1) the catastrophic emplacement of Te Whaiau Formation (60-55 ka); (2) major episodes of effusive activity (c. 30 ka and c. 15 ka); and (3) syn- and post-eruptive lahar aggradation on the shores of Lake Rotoaira. Stratigraphic unconformities, fluvial and aeolian reworking, and subsequent volcanogenic sedimentation indicate that climate change driven periods of erosion contributed significantly to the evolution of the landscape during the late Quaternary. Waters that accumulated in a newly expanded graben formed Lake Rotoaira. An attempt to core through the sediments on the lake's floor revealed a >6.5 m thick mantling of Taupo ignimbrite, restricting chronostratigraphic sampling to the last 1.85 ka. Lake Rotoaira pollen profiles record: (1) the destruction of the indigenous forest by the Taupo ignimbrite eruption; (2) the following period of vegetation recovery (c. 300 yr); and (3) periods of human occupation of the lakeshores (bracken spores and Pinus pollen) in the younger sediments. Coarse sand generated by the 1995-96 tephra-producing Ruapehu eruptions also contributed to the recent lake sedimentation. (author). 59 refs., 9 figs., 1 tab

  17. 26Al/10Be burial dating of Xujiayao-Houjiayao site in Nihewan Basin, northern China.

    Directory of Open Access Journals (Sweden)

    Hua Tu

    Full Text Available The Xujiayao-Houjiayao site in Nihewan Basin is among the most important Paleolithic sites in China for having provided a rich collection of hominin and mammalian fossils and lithic artifacts. Based on biostratigraphical correlation and exploratory results from a variety of dating methods, the site has been widely accepted as early Upper Pleistocene in time. However, more recent paleomagnetic analyses assigned a much older age of ∼500 ka (thousand years. This paper reports the application of 26Al/10Be burial dating as an independent check. Two quartz samples from a lower cultural horizon give a weighted mean age of 0.24 ± 0.05 Ma (million years, 1σ. The site is thus younger than 340 ka at 95% confidence, which is at variance with the previous paleomagnetic results. On the other hand, our result suggests an age of older than 140 ka for the site's lower cultural deposits, which is consistent with recent post-infrared infrared stimulated luminescence (pIR-IRSL dating at 160-220 ka.

  18. Molecular analysis reveals the diversity of Hepatozoon species naturally infecting domestic dogs in a northern region of Brazil.

    Science.gov (United States)

    Gomes, Laise de Azevedo; Moraes, Pablo Henrique Gonçalves; do Nascimento, Luciana de Cássia Silva; O'Dwyer, Lucia Helena; Nunes, Márcio Roberto Teixeira; Rossi, Adriana Dos Reis Ponce; Aguiar, Délia Cristina Figueira; Gonçalves, Evonnildo Costa

    2016-10-01

    This study aimed to optimize molecular methods for detecting DNA of Hepatozoon spp. as well as identify the phylogenetic relationships of Hepatozoon strains naturally infecting domestic dogs in Belém, Pará, northern Brazil. Blood samples were collected from 138 dogs, and screened for Hepatozoon spp. using a new nested PCR assay. Positive samples were subjected to genetic characterization based on amplification and sequencing of approximately 670bp of the Hepatozoon spp. 18S rRNA. Of the positive dogs, four shared the haplotype Belém 01, one dog presented the haplotype Belém 02 and two dogs shared the haplotype Belém 03. A Bayesian inference indicates that haplotypes Belém 01 and Belém 02 are phylogenetically related to H. canis, while Belém 03 is related to H. americanum. Overall, based on the first molecular evidence of H. americanum in Brazilian domestic dogs, the proposed protocol may improve the epidemiological investigation of canine hepatozoonosis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Infection by Neospora caninum in dairy cattle belonging to family farmers in the northern region of Brazil.

    Science.gov (United States)

    Boas, Ricardo Vilas; Pacheco, Thábata dos Anjos; Melo, Andréia Lima Tomé; de Oliveira, Anderson Castro Soares; de Aguiar, Daniel Moura; Pacheco, Richard de Campos

    2015-01-01

    Neosporosis is considered a major cause of abortion among cattle worldwide. The aim of this study was to investigate the prevalence of anti-Neospora caninum antibodies in dairy cattle and correlate them with possible risk factors on 63 small farms (family farms) in the municipality of Ji-Paraná, the main milk-producing region of the state of Rondônia, northern Brazil. For this purpose, 621 serum samples were collected from cows and were evaluated by means of the indirect fluorescence antibody test (IFAT). The overall herd prevalence of N. caninum antibodies among the farms (38/63; 60.31%) showed that N. caninum are widespread among the dairy herds in this region, despite only infecting a small proportion of animals (66/621, 10.62%). Occurrences of abortion and birth of weak calves were the only variables that showed as risk factors for the presence of N. caninum. The result from the spatial lag model strongly indicated that birth of weak calves and presence of N. caninum are occurring on farms that are located close to each other, indicating aggregation of disease occurrence.

  20. Identification and phylogenetic inferences on stocks of sharks affected by the fishing industry off the Northern coast of Brazil

    Directory of Open Access Journals (Sweden)

    Luis Fernando da Silva Rodrigues-Filho

    2009-01-01

    Full Text Available The ongoing decline in abundance and diversity of shark stocks, primarily due to uncontrolled fishery exploitation, is a worldwide problem. An additional problem for the development of conservation and management programmes is the identification of species diversity within a given area, given the morphological similarities among shark species, and the typical disembarkation of processed carcasses which are almost impossible to differentiate. The main aim of the present study was to identify those shark species being exploited off northern Brazil, by using the 12S-16S molecular marker. For this, DNA sequences were obtained from 122 specimens collected on the docks and the fish market in Bragança, in the Brazilian state of Pará. We identified at least 11 species. Three-quarters of the specimens collected were either Carcharhinus porosus or Rhizoprionodon sp, while a notable absence was the daggernose shark, Isogomphodon oxyrhyncus, previously one of the most common species in local catches. The study emphasises the value of molecular techniques for the identification of cryptic shark species, and the potential of the 12S-16S marker as a tool for phylogenetic inferences in a study of elasmobranchs.

  1. Structure of parasites community in Chaetobranchopsis orbicularis (Cichlidae), a host from the Amazon River system in northern Brazil.

    Science.gov (United States)

    Tavares-Dias, Marcos; Oliveira, Marcos Sidney Brito

    2017-08-01

    The aim of this paper was to investigate the component communities of parasites in Chaetobranchopsis orbicularis from a tributary of the Amazon River system, in Northern Brazil. In 32 fish examined, 902,551 parasites were collected, including Ichthyophthirius multifiliis, Piscinoodinium pillulare, Sciadicleithrum geophagi, Posthodiplostomum sp., Clinostomum marginatum, Echinorhynchus paranensis, Neoechinorhynchus pterodoridis, and Dolops longicauda. I. multifiliis was the dominant and abundant parasite species. The ectoparasites presented aggregate dispersion, but the endoparasites showed random dispersion pattern. Mean species richness was 4.0 ± 1.5 parasites, mean Brillouin diversity (HB) was 0.33 ± 0.28, mean evenness was 0.15 ± 0.13, and Berger-Parker dominance (d) was 0.85 ± 0.17. The species richness of parasites and HB were positively correlated with the length of hosts. There was positive correlation between the abundance of P. pillulare and length and weight, between the abundance of I. multifiliis and weight, as well as between the abundance of E. paranensis and N. pterodoridis and the length of hosts. Body condition of the hosts was not affected by moderate parasitism. The low diversity of endoparasites indicates that C. orbicularis is a host with low position in the food web. This is the first record of all these parasites for C. orbicularis.

  2. [Use of illicit drugs and critical perspectives of drug users' relatives and acquaintances in Northern Rio de Janeiro City, Brazil].

    Science.gov (United States)

    Vargens, Octavio Muniz da Costa; Brands, Bruna; Adlaf, Edward; Giesbrecht, Norman; Simich, Laura; Wright, Maria da Gloria Miotto

    2009-01-01

    This article presents the partial results of a multicenter, qualitative study, which involved seven Latin-American countries and Canada. The results presented refer to Northern Rio de Janeiro (city), Brazil. The objective of the study was to describe the perspective of relatives/acquaintances of illicit drug users about protective and risk factors, prevention initiatives, treatment services, and legal aspects regarding illicit drugs. Interviews were performed with 99 individuals, who reported being affected by their relationship with an illicit drug user (relative or acquaintance), approaching their perspectives regarding the key-domains. Most participants were women (73.7%); relatives who used drugs were mostly men (78.2%); the most consumed drug was marijuana (77.8%). The highlighted protective factor was having recreational-sports activities in the community (88.9%), and the risk factor was curiosity for trying something new (94.4%). The main treatment services were Church Groups (51.5%), and participants stated that laws should be more punitive (82.8%). In conclusion, this information is essential to fight against drug use/abuse, showing that there is a need for actions that consider different perspectives at different levels.

  3. Tectonic evolution of the Qumran Basin from high-resolution 3.5-kHz seismic profiles and its implication for the evolution of the northern Dead Sea Basin

    Science.gov (United States)

    Lubberts, Ronald K.; Ben-Avraham, Zvi

    2002-02-01

    The Dead Sea Basin is a morphotectonic depression along the Dead Sea Transform. Its structure can be described as a deep rhomb-graben (pull-apart) flanked by two block-faulted marginal zones. We have studied the recent tectonic structure of the northwestern margin of the Dead Sea Basin in the area where the northern strike-slip master fault enters the basin and approaches the western marginal zone (Western Boundary Fault). For this purpose, we have analyzed 3.5-kHz seismic reflection profiles obtained from the northwestern corner of the Dead Sea. The seismic profiles give insight into the recent tectonic deformation of the northwestern margin of the Dead Sea Basin. A series of 11 seismic profiles are presented and described. Although several deformation features can be explained in terms of gravity tectonics, it is suggested that the occurrence of strike-slip in this part of the Dead Sea Basin is most likely. Seismic sections reveal a narrow zone of intensely deformed strata. This zone gradually merges into a zone marked by a newly discovered tectonic depression, the Qumran Basin. It is speculated that both structural zones originate from strike-slip along right-bending faults that splay-off from the Jordan Fault, the strike-slip master fault that delimits the active Dead Sea rhomb-graben on the west. Fault interaction between the strike-slip master fault and the normal faults bounding the transform valley seems the most plausible explanation for the origin of the right-bending splays. We suggest that the observed southward widening of the Dead Sea Basin possibly results from the successive formation of secondary right-bending splays to the north, as the active depocenter of the Dead Sea Basin migrates northward with time.

  4. The influence of oceanic basins on drought and ecosystem dynamics in Northeast Brazil

    International Nuclear Information System (INIS)

    Pereira, Marcos Paulo Santos; Justino, Flavio; Malhado, Ana Claudia Mendes; Barbosa, Humberto; Marengo, José

    2014-01-01

    The 2012 drought in Northeast Brazil was the harshest in decades, with potentially significant impacts on the vegetation of the unique semi-arid caatinga biome and on local livelihoods. Here, we use a coupled climate–vegetation model (CCM3-IBIS) to: (1) investigate the role of the Pacific and Atlantic oceans in the 2012 drought, and; (2) evaluate the response of the caatinga vegetation to the 2012 climate extreme. Our results indicate that anomalous sea surface temperatures (SSTs) in the Atlantic Ocean were the primary factor forcing the 2012 drought, with Pacific Ocean SST having a larger role in sustaining typical climatic conditions in the region. The drought strongly influenced net primary production in the caatinga, causing a reduction in annual net ecosystem exchange indicating a reduction in amount of CO 2 released to the atmosphere. (letter)

  5. Changes in Bottom Water Physical Properties Above the Mid-Atlantic Ridge Flank in the Brazil Basin

    Science.gov (United States)

    Zhao, Jian; Thurnherr, Andreas M.

    2018-01-01

    Warming of abyssal waters in recent decades has been widely documented around the global ocean. Here repeat hydrographic data collected in 1997 and 2014 near a deep fracture zone canyon in the eastern Brazil Basin are used to quantify the long-term change. Significant changes are found in the Antarctic Bottom Water (AABW) within the canyon. The AABW in 2014 was warmer (0.08 ± 0.06°C), saltier (0.01 ± 0.005), and less dense (0.005 ± 0.004 kg m-3) than in 1997. In contrast, the change in the North Atlantic Deep Water has complicated spatial structure and is almost indistinguishable from zero at 95% confidence. The resulting divergence in vertical displacement of the isopycnals modifies the local density stratification. At its peak, the local squared buoyancy frequency (N2) near the canyon is reduced by about 20% from 1997 to 2014. Similar reduction is found in the basinwide averaged profiles over the Mid-Atlantic Ridge flank along 25°W in years 1989, 2005, and 2014. The observed changes in density stratification have important implications for internal tide generation and dissipation.

  6. Development of cataclastic foliation in deformation bands in feldspar-rich conglomerates of the Rio do Peixe Basin, NE Brazil

    Science.gov (United States)

    Nicchio, Matheus A.; Nogueira, Francisco C. C.; Balsamo, Fabrizio; Souza, Jorge A. B.; Carvalho, Bruno R. B. M.; Bezerra, Francisco H. R.

    2018-02-01

    In this work we describe the deformation mechanisms and processes that occurred during the evolution of cataclastic deformation bands developed in the feldspar-rich conglomerates of the Rio do Peixe Basin, NE Brazil. We studied bands with different deformation intensities, ranging from single cm-thick tabular bands to more evolved clustering zones. The chemical identification of cataclastic material within deformation bands was performed using compositional mapping in SEM images, EDX and XRD analyses. Deformation processes were identified by microstructural analysis and by the quantification of comminution intensity, performed using digital image processing. The deformation bands are internally non homogeneous and developed during five evolutionary stages: (1) moderate grain size reduction, grain rotation and grain border comminution; (2) intense grain size reduction with preferential feldspar fragmentation; (3) formation of subparallel C-type slip zones; (4) formation of S-type structures, generating S-C-like fabric; and (5) formation of C‧-type slip zones, generating well-developed foliation that resembles S-C-C‧-type structures in a ductile environment. Such deformation fabric is mostly imparted by the preferential alignment of intensely comminuted feldspar fragments along thin slip zones developed within deformation bands. These processes were purely mechanical (i.e., grain crushing and reorientation). No clays or fluids were involved in such processes.

  7. Sedimentation rates in Atibaia River basin, São Paulo State, Brazil, using 210Pb as geochronometer.

    Science.gov (United States)

    Sabaris, T P P; Bonotto, D M

    2011-01-01

    The constant initial concentration (CIC) of unsupported/excess (210)Pb model was successfully used to assess (210)Pb data of nine sediment cores from Atibaia River basin, São Paulo State, Brazil. The (210)Pb-based apparent sediment mass accumulation rates ranged from 47.7 to 782.4 mg/cm(2)yr, whereas the average linear sedimentation rates between 0.16 and 1.32 cm/yr, which are compatible with the calculated sediment mass fluxes, i.e. a higher sediment mass accumulation rate yielded a higher linear sedimentation rate. The higher long-term based accumulation rate tended to be found in topographically softer regions. This occurs because the sediments are preferentially transported in topographically steeper regions instead of being deposited. Anthropic activities like deforestation possibly interfered with the natural/normal sedimentation processes, which increased in accordance with modifications on the channel drainage. The radionuclide geochronology as described in this paper allows determination of sedimentation rates that are compatible with values estimated elsewhere. The adoption of an appropriate factor generated from previous laboratory experiments resulted in a successful correction for the (222)Rn-loss from the sediments, bringing the estimate of the parent-supported (in-situ produced) (210)Pb to reliable values required by the CIC model. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Irradiation of quartz grains - a new method of sedimentological analysis applied to Permian - Carboniferous arenites in the Maranhao Basin - Brazil

    International Nuclear Information System (INIS)

    Carmo Faria Junior, L.E. do

    1980-01-01

    The quartz grains of sediments and sedimentary rocks change their colour in variable intensity to smoky-quartz by X-ray irradiation, Co 60 or in reactors, dependent on their temperature of cristallization. The quantity of quartz grains which were stained and which were not stained after being irradiated are related to rock types from the source areas. This method was applied for selected sandstones of different stratigraphical levels of the Permian-Carboniferous in the Maranhao Basin of Brazil. Studeis on heavy minerals of these sandstones have been done before. The heavy mineral associations of the Permian Pedra de Fogo Formation corroborate the results of the analysis of quartz grains which indicate a predominance of the metamorphic rocks in the source area. However, the heavy mineral parageneses of the Carboniferous Piaui Formation are different. This may be because the frequency of those heavy minerals depend directly on the stage of the weathering of the sandstones. It should be mentioned that heavy minerals occur in paleozoic sediments only in a small quantity, sometimes below 1% of the rock constitution. The irradiation analysis, which is applied for the predominant mineral in sandstones, appears to be most reliable. It is used here as the basis for the interpretations presented. (Author) [pt

  9. The aquatic environment as a reservoir of Vibrio cholerae O1 in hydrographic basins of the state of Pernambuco, Brazil.

    Science.gov (United States)

    Mendes-Marques, Carina Lucena; Silveira Filho, Vladimir da Mota; da Costa, Ana Paula Rocha; Nunes, Mariana de Lira; da Silva Filho, Sandoval Vieira; Figueirôa, Ângela Cristina Torres de Araújo; Hofer, Ernesto; de Almeida, Alzira Maria Paiva; Leal, Nilma Cintra

    2013-01-01

    After the worldwide cholera epidemic in 1993, permanent environmental monitoring of hydrographic basins was established in Pernambuco, Brazil, where cholera is endemic. After a quiescent period, 4 rfbN (serogroup O1) positive water samples that were culture negative were detected by multiplex single-tube nested PCR (MSTNPCR); 2 of these were also ctxA (cholera toxin) positive. From May to June 2012, 30 V. cholerae O1 isolates were obtained by culturing samples. These isolates were analyzed for the presence of virulence genes by PCR, intergenic spacer region 16S-23S PCR (ISR-PCR), and pulsed field gel electrophoresis (PFGE). The isolates were positive for the rfbN gene and negative for the assessed pathogenic genes and were classified into 2 groups by ISR and the same profile by PFGE. Close genetic similarity was observed between them (2012) and environmental strains from 2004 to 2005, indicating the permanence of endemic V. cholerae O1 in the region.

  10. The Aquatic Environment as a Reservoir of Vibrio cholerae O1 in Hydrographic Basins of the State of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Carina Lucena Mendes-Marques

    2013-01-01

    Full Text Available After the worldwide cholera epidemic in 1993, permanent environmental monitoring of hydrographic basins was established in Pernambuco, Brazil, where cholera is endemic. After a quiescent period, 4 rfbN (serogroup O1 positive water samples that were culture negative were detected by multiplex single-tube nested PCR (MSTNPCR; 2 of these were also ctxA (cholera toxin positive. From May to June 2012, 30 V. cholerae O1 isolates were obtained by culturing samples. These isolates were analyzed for the presence of virulence genes by PCR, intergenic spacer region 16S-23S PCR (ISR-PCR, and pulsed field gel electrophoresis (PFGE. The isolates were positive for the rfbN gene and negative for the assessed pathogenic genes and were classified into 2 groups by ISR and the same profile by PFGE. Close genetic similarity was observed between them (2012 and environmental strains from 2004 to 2005, indicating the permanence of endemic V. cholerae O1 in the region.

  11. A seroprevalence and descriptive epidemiological study of malaria among Indian tribes of the Amazon basin of Brazil.

    Science.gov (United States)

    de Arruda, M E; Aragaki, C; Gagliardi, F; Haile, R W

    1996-04-01

    Data on the seroprevalences of Plasmodium falciparum, P. vivax, and P. malariae in four isolated Indian tribes of the Amazon basin in Brazil, as determined by IFAT, were re-analysed. Age-, sex- and tribe-specific geometric mean antibody titres and externally standardized prevalence ratios were calculated for each parasite species. Correlation coefficients and prevalence odds ratios were also calculated for multiple infections with different combinations of the three Plasmodium species. Titres of all but one of the antibodies studied were similar in males and females; titres of antibodies to the blood stages of P. malariae were slightly higher in females than in males. Titres of antibodies to all three Plasmodium species increased with subject age, and this age effect was not confounded by sex or tribal differences. There were striking differences between tribes, with the Parakana tribe having relatively low titres of antibodies against P. falciparum and P. malariae; these tribal effects were not confounded by sex or age differences between tribes. The results indicate that conditions conductive to the transmission of P. malariae exist in this region of the Amazon. The potential for zoonotic transmission of P. brasilianum, a parasite of monkeys which is morphologically similar to P. malarie, and the generally high rates of seropositivity to all three species of Plasmodium indicate that control measures which are adequate and applicable to the region studied need to be developed.

  12. Analyses of infrequent (quasi-decadal) large groundwater recharge events in the northern Great Basin: Their importance for groundwater availability, use, and management

    Science.gov (United States)

    Masbruch, Melissa D.; Rumsey, Christine; Gangopadhyay, Subhrendu; Susong, David D.; Pruitt, Tom

    2016-01-01

    There has been a considerable amount of research linking climatic variability to hydrologic responses in the western United States. Although much effort has been spent to assess and predict changes in surface water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on characterizing and quantifying the effects of large, multiyear, quasi-decadal groundwater recharge events in the northern Utah portion of the Great Basin for the period 1960–2013. Annual groundwater level data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified with a frequency of about 11–13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single recharge event ranged from about 115 to 205 Mm3. Extrapolating these amounts over the entire northern Great Basin indicates that a single large quasi-decadal recharge event could result in billions of cubic meters of groundwater storage. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for long-term groundwater management.

  13. Assessment of River Habitat Quality in the Hai River Basin, Northern China

    Directory of Open Access Journals (Sweden)

    Yuekui Ding

    2015-09-01

    Full Text Available We applied a river habitat quality (RHQ assessment method to the Hai River Basin (HRB; an important economic centre in China; to obtain baseline information for water quality improvement; river rehabilitation; and watershed management. The results of the assessment showed that the river habitat in the HRB is seriously degraded. Specifically; 42.41% of the sites; accounting for a river length of 3.31 × 104 km; were designated poor and bad. Habitat in the plain areas is seriously deteriorated; and nearly 50% of the sites; accounting for a river length of 1.65 × 104 km; had either poor or bad habitats. River habitat degradation was attributable to the limited width of the riparian zone (≤5 m; lower coverage of riparian vegetation (≤40%; artificial land use patterns (public and industrial land; frequent occurrence of farming on the river banks and high volumes of solid waste (nearly 10 m3; single flow channels; and rare aquatic plants (≤1 category. At the regional scale; intensive artificial land use types caused by urbanization had a significant impact on the RHQ in the HRB. RHQ was significantly and negatively correlated with farmland (r = 1.000; p < 0.01 and urban land (r = 0.998; p < 0.05; and was significantly and positively correlated with grassland and woodland (r = 1.000; p < 0.01. Intensive artificial land use; created through urbanization processes; has led to a loss of the riparian zone and its native vegetation; and has disrupted the lateral connectivity of the rivers. The degradation of the already essentially black rivers is exacerbated by poor longitudinal connectivity (index of connectivity is 2.08–16.56; caused by reservoirs and sluices. For river habitat rehabilitation to be successful; land use patterns need to be changed and reservoirs and sluices will have to be regulated.

  14. Geological and geochronological evidence for the effect of Paleogene and Miocene uplift of the Northern Ordos Basin on the formation of the Dongsheng uranium district, China

    Science.gov (United States)

    Zhang, Chuang; Yi, Chao; Dong, Qian; Cai, Yu-Qi; Liu, Hong-Xu

    2018-02-01

    The Dongsheng uranium district, located in the northern part of the Ordos Basin, contains the largest known sandstone-hosted uranium deposit in China. This district contains (from west to east) the Daying, Nalinggou, and Dongsheng uranium deposits that host tens of thousands of metric tonnes of estimated recoverable uranium resources at an average grade of 0.05% U. These uranium orebodies are generally hosted by the lower member of the Zhiluo Formation and are dominantly roll or tabular in shape. The uranium deposits in this district formed during two stages of mineralization (as evidenced by U-Pb dating) that occurred at 65-60 and 25 Ma. Both stages generated coffinite, pitchblende, anatase, pyrite, and quartz, with or without sericite, chlorite, calcite, fluorite, and hematite. The post-Late Cretaceous uplift of the Northern Ordos Basin exposed the northern margins of the Zhiluo Formation within the Hetao depression at 65-60 Ma, introducing groundwater into the formation and generating the first stage of uranium mineralization. The Oligocene (∼25 Ma) uplift of this northern margin exposed either the entirety of the southern flank of the Hetao depression or only the clastic sedimentary part of this region, causing a second gravitational influx of groundwater into the Zhiluo Formation and forming the second stage of uranium mineralization.

  15. A new species of Moenkhausia Eigenmann (Characiformes: Characidae from the rio Xingu basin, Brazil

    Directory of Open Access Journals (Sweden)

    Manoela M. F. Marinho

    Full Text Available A new species of Moenkhausia from the upper rio Xingu basin is described. Moenkhausia eurystaenia is distinguished from all congeners, except M. heikoi and M. phaeonota, by the presence of a dark, broad longitudinal stripe from the opercle to the end of caudal peduncle. The new species is distinguished from M. heikoi mainly by having 18-21 branched anal-fin rays (vs. 24-26 and the absence of a round blotch at the end of the caudal peduncle (vs. present. Moenkhausia eurystaenia can be distinguished from M. phaeonota mainly by the anterior portion of longitudinal band darker at horizontal septum (vs. darker below horizontal septum, the deep dark pigmentation along horizontal septum extending anteriorly up to humeral region (vs. extending up to vertical through pelvic-fin origin, number of vertebrae 34 (vs. 36-37, and others additional measurements.

  16. Spectroscopic Analysis of a Theropod Dinosaur (Reptilia, Archosauria from the Ipubi Formation, Araripe Basin, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    João Hermínio da Silva

    2013-01-01

    Full Text Available The Araripe Sedimentary Basin is known by the excellence of its fossils, regarding the preservation, diversity, and quantity. Here, we present a spectroscopic analysis using several experimental techniques (X-ray energy dispersion spectroscopy, Fourier-transform infrared spectroscopy as well as X-ray diffraction and thermogravimetric analysis applied in small fragments of bones from the posterior members of a theropod dinosaur. The results agree regarding the different composition of the stone matrix and the fossilized bone, indicating a partial substitution of the material by elements present in the depositional environment. However, differently from what is believed to occur, there is evidence that pyritization is not the only mechanism of fossilization for a specimen of Ipubi formation, but calcification, additionally, plays an important role in the fossil production of this Formation.

  17. Flora and phytosociology of an area of Restinga along the northern Coast of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Christiano Marcelino Menezes

    2012-03-01

    Full Text Available Areas of restinga are geologically recent environments. The species that inhabit this type of ecosystem are typical of adjacent areas, such as rain forest, tabuleiro forest and caatinga, and form a diverse community of trees, shrubs and erect and prostrate herbs. The goal of this work was to evaluate the vegetation in an area of restinga located along Praia do Forte, in the state of Bahia, Brazil. Four 200m transects where made within five plots of 100m2 each, and 1,640 individuals within 68 species were collected. High species diversity was found in transects 1 and 2 (H´ = 3.882 and 3 and 4 (H´ = 3.835. The most representative families were Myrtaceae, Rubiaceae and Malpighiaceae. Based on the species composition, a significant difference (p < 0.001 was found between the sampled areas, and the findings show that there are two distinct plant communities in this region, Mata deRestinga and Restinga em Moitas.

  18. Two new endangered species of Anomaloglossus (Anura: Aromobatidae) from Roraima State, northern Brazil.

    Science.gov (United States)

    Fouquet, Antoine; Souza, Sergio Marques; Nunes, Pedro M Sales; Kok, Philippe J R; Curcio, Felipe Franco; De Carvalho, Celso Morato; Grant, Taran; Rodrigues, Miguel Trefaut

    2015-03-05

    We describe two new species of Anomaloglossus from Roraima State, Brazil, that are likely endemic to single mountains currently isolated among lowland forest and savanna ecosystems. The first species, Anomaloglossus tepequem sp. nov. was collected in 1986 and 1992 along a single stream at >500 m elevation on a tepui-like mountain named Tepequém, but was not detected during recent investigations. It is mainly diagnosed from other Anomaloglossus species by its well developed foot webbing, immaculate cream abdomen colouration and small body size (males: 18.2-20.1 mm, females: 21.7-24.5). The second species, Anomaloglossus apiau sp. nov. was found along several streams between 500 and 1400 m elevation on Serra do Apiaú, and is mainly diagnosed from congeners by its weakly webbed feet, males with swollen third finger and ventrolateral stripe formed by white dots, and its advertisement call; a long trill (up to almost 40 s) consisting of pairs of very short pulses. The discovery of these two apparently microendemic species suggests that additional Anomaloglossus species remain to be described in the Guiana Shield. Both species should be considered critically endangered given their seemingly reduced range size, association with highland habitat, and the anthropogenic pressure they currently face.

  19. Associated factors of overweight in adolescents from public schools in Northern Minas Gerais State, Brazil.

    Science.gov (United States)

    de Pinho, Lucinéia; Botelho, Ana Cristina de C; Caldeira, Antônio Prates

    2014-06-01

    In order to support plans and actions that combat the local increasing overweight and obesity prevalence in adolescents, the factors associated to weight excess in public school students from Montes Claros, MG, Southeast Brazil, were studied. Cross-sectional study with a sample of adolescents from the public schools of the city. The nutritional status was evaluated and an inquiry was carried out in the schools to determine food consumption and practice of physical activities. Factors associated to weight excess were assessed by bivariate analysis followed by logistic regression. Weight excess prevalence was detected in 18.5% of the 535 adolescents evaluated. The factors associated to weight excess were: per capita income above half minimum wage (OR 1.99; 95%CI 1.01-3.93), candy consumption above two daily portions (OR 1.94; 95%CI 1.13-3.32) and absence of sport activity during leisure time (OR 2.54; 95%CI 1.15-5.59). The proportion of weight excess in adolescents from public schools is relevant and associated with socioeconomic condition of the family, bad eating habits and sedentary life.

  20. Genetic variability of populations of Nyssomyia neivai in the Northern State of Paraná, Brazil

    Science.gov (United States)

    Gasparotto, Jaqueline de Carvalho; da Costa-Ribeiro, Magda Clara Vieira; Thomaz-Soccol, Vanete; Liebel, Sandra Mara Rodrigues da Silva; Neitzke-Abreu, Herintha Coeto; Reinhold-Castro, Kárin Rosi; Cristovão, Edilson Colhera; Teodoro, Ueslei

    2017-01-01

    ABSTRACT The genetic study of sandfly populations needs to be further explored given the importance of these insects for public health. Were sequenced the NDH4 mitochondrial gene from populations of Nyssomyia neivai from Doutor Camargo, Lobato, Japira, and Porto Rico, municipalities in the State of Paraná, Brazil, to understand the genetic structure and gene flow. Eighty specimens of Ny. Neivai were sequenced, 20 from each municipality, and 269 base pairs were obtained. A total of 27 haplotypes and 28 polymorphic sites were found, along with a haplotypic diversity of 0.80696 and a nucleotide diversity of 0.00567. Haplotype H5, with 33 specimens, was the most common among the four populations. Only haplotypes H5 and H7 were present in all four populations. The population from Doutor Camargo showed the highest genetic diversity, and only this population shared haplotypes with those from the other municipalities. The highest number of haplotypes was sheared with Lobato which also had the highest number of unique haplotypes. This probably occurred because of constant anthropic changes that happened in the environment during the first half of the twentieth century, mainly after 1998. There was no significant correlation between genetic and geographical distances regarding these populations. However, the highest genetic and geographical distances, and the lowest gene flow were observed between Japira and Porto Rico. Geographical distance is a possible barrier between these municipalities through the blocking of haplotype sharing. PMID:28380111

  1. Genetic variability of populations of Nyssomyia neivai in the Northern State of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Jaqueline de Carvalho Gasparotto

    Full Text Available ABSTRACT The genetic study of sandfly populations needs to be further explored given the importance of these insects for public health. Were sequenced the NDH4 mitochondrial gene from populations of Nyssomyia neivai from Doutor Camargo, Lobato, Japira, and Porto Rico, municipalities in the State of Paraná, Brazil, to understand the genetic structure and gene flow. Eighty specimens of Ny. Neivai were sequenced, 20 from each municipality, and 269 base pairs were obtained. A total of 27 haplotypes and 28 polymorphic sites were found, along with a haplotypic diversity of 0.80696 and a nucleotide diversity of 0.00567. Haplotype H5, with 33 specimens, was the most common among the four populations. Only haplotypes H5 and H7 were present in all four populations. The population from Doutor Camargo showed the highest genetic diversity, and only this population shared haplotypes with those from the other municipalities. The highest number of haplotypes was sheared with Lobato which also had the highest number of unique haplotypes. This probably occurred because of constant anthropic changes that happened in the environment during the first half of the twentieth century, mainly after 1998. There was no significant correlation between genetic and geographical distances regarding these populations. However, the highest genetic and geographical distances, and the lowest gene flow were observed between Japira and Porto Rico. Geographical distance is a possible barrier between these municipalities through the blocking of haplotype sharing.

  2. Water isotopic characterization of hypersaline formation of a petroleum field Reconcavo basin, Brazil

    International Nuclear Information System (INIS)

    Teles, Danilo Ribeiro de Sa; Azevedo, Antonio Expedito Gomes de

    2010-01-01

    Formation water is the water present in reservoir rock pores, produced together with petroleum. Usually it is hyper saline with concentrations that can be higher than 250 g/l of dissolved solids. The concentration of the dissolved elements and the isotopic composition of the water and of some of the dissolved elements can be excellent tracers to study the dynamic of underground fluid flux, the mixing of distinct sources and the origin of salinization of these waters. This work reports the isotopic composition (δ 2 H , δ 18 O) and electrical conductivity (EC) of formation waters from 10 wells of a petroleum field of the Reconcavo Basin, looking for their evolution, interaction with the minerals and rocks and reservoir interconnection. The samples have electric conductivity ranging from 84 to 137 mS/cm, with conductivity increasing with depth of production zone. It is observed an enrichment of deuterium and oxygen-18 with the depth of production zone, probably due to water-rock interactions that were probably increased by higher temperatures of the deeper levels and longer residence times. The samples from the production zone between 1450 to 1520 m, drained by 7 of the 10 wells sampled, show a small range in isotopic composition and in electric conductivity, indicating homogeneity in this level of the reservoir. In the shallow level of 450 m the values of δ 2 H , δ 18 O and EC are lower, with isotopic composition similar to the oceanic water, possibly representing the original water that entered the reservoir during the sedimentation of the basin. (author)

  3. Dealing with variability in water availability: the case of the Verde Grande River basin, Brazil

    Directory of Open Access Journals (Sweden)

    B. Collischonn

    2014-09-01

    Full Text Available This paper presents a water resources management strategy developed by the Brazilian National Water Agency (ANA to cope with the conflicts between water users in the Verde Grande River basin, located at the southern border of the Brazilian semi-arid region. The basin is dominated by water-demanding fruit irrigation agriculture, which has grown significantly and without adequate water use control, over the last 30 years. The current water demand for irrigation exceeds water availability (understood as a 95 % percentile of the flow duration curve in a ratio of three to one, meaning that downstream water users are experiencing more frequent water shortages than upstream ones. The management strategy implemented in 2008 has the objective of equalizing risk for all water users and consists of a set of rules designed to restrict water withdrawals according to current river water level (indicative of water availability and water demand. Under that rule, larger farmers have proportionally larger reductions in water use, preserving small subsistence irrigators. Moreover, dry season streamflow is forecasted at strategic points by the end of every rainy season, providing evaluation of shortage risk. Thus, water users are informed about the forecasts and corresponding restrictions well in advance, allowing for anticipated planning of irrigated areas and practices. In order to enforce restriction rules, water meters were installed in all larger water users and inefficient farmers were obligated to improve their irrigation systems’ performance. Finally, increases in irrigated area are only allowed in the case of annual crops and during months of higher water availability (November to June. The strategy differs from convectional approached based only on water use priority and has been successful in dealing with natural variability of water availability, allowing more water to be used in wet years and managing risk in an isonomic manner during dry years.

  4. Sedimentary provenance in the southern sector of the São Francisco Basin, SE Brazil

    Directory of Open Access Journals (Sweden)

    Gustavo Macedo de Paula-Santos

    Full Text Available ABSTRACT: We present new Sm-Nd, U-Pb and Hf isotope geochronological data for the siliciclastic rocks in the southern sector of the São Francisco Basin. An abrupt change in the Sm-Nd data is observed from the Carrancas Formation’s oligomitic conglomerates (TDM ages between 2.7 and 3.3 Ga; εNd(550 Ma values between -25.09 and -17.98, its finer facies, and the finer facies of the the Moema Laminite (TDM ages from 1.4 to 2.1 Ga; εNd(550 Ma values between -9.46 and -5.59. No further significant changes in the Sm-Nd data occur farther upwards in the Bambuí Group (Sm-Nd TDM ages within the 1.3-2.0 Ga interval; εNd(550 Ma values from -9.53 to -4.09, showing a lack of reorganization in the source areas throughout the deposition of the basin. This is yet another argument to dismiss an unconformity within the Bambuí Group. The presence of the index fossil Cloudina sp. in the lower Sete Lagoas Formation makes the glaciation probably Late Ediacaran in age. U-Pb ages for detrital zircons of the Bambuí Group range from the Archean to the early Ediacaran, but the current data is insufficient to distinguish between the contribution from sources in the Brasília and Araçuaí belts.

  5. 210Pb and compositional data of sediments from Rondonian lakes, Madeira River basin, Brazil

    International Nuclear Information System (INIS)

    Bonotto, Daniel Marcos; Vergotti, Marcelo

    2015-01-01

    Gold exploration has been intensive in Brazilian Amazon over the last 40 years, where the use of mercury as an amalgam has caused abnormal Hg concentrations in water bodies. Special attention has been directed to Madeira River due to fact it is a major tributary of Amazon River and that since 1986, gold exploration has been officially permitted along a 350 km sector of the river. The 210 Pb method has been used to date sediments taken from nine lakes situated in Madeira River basin, Rondônia State, and to verify where anthropogenic Hg might exist due to gold exploitation in Madeira River. Activity profiles of excess 210 Pb determined in the sediment cores provided a means to evaluate the sedimentation rates using a Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) of unsupported/excess 210 Pb models. A significant relationship was found between the CF:CS sedimentation rates and the mean values of the CRS sedimentation rates (Pearson correlation coefficient r=0.59). Chemical data were also determined in the sediments for identifying possible relationships with Hg occurring in the area. Significant values were found in statistical correlation tests realized among the Hg, major oxides and Total Organic Carbon (TOC) content in the sediments. The TOC increased in the sediment cores accompanied by a loss on ignition (LOI) increment, whereas silica decreased following a specific surface area raising associated to the TOC increase. The CRS model always provided ages within the permitted range of the 210 Pb-method in the studied lakes, whereas the CF:CS model predicted two values above 140 years. - Highlights: • Gold mining activities. • Madeira River basin at Amazon area. • Pb-210 chronological method. • Models for evaluating sedimentation rates

  6. Structure and Stratigraphy of the Rift Basins in the Northern Gulf of California: Results from Analysis of Seismic Reflection and Borehole Data.

    Science.gov (United States)

    Martín, A.; González, M.; Helenes, J.; García, J.; Aragón, M.; Carreño, A.

    2008-12-01

    The northern Gulf of California contains two parallel, north-south trending rift basin systems separated by a basement-high. The interpretation of several exploration wells, and ~4500 km of seismic reflection data from PEMEX (Mexican national oil company) indicate that the tectonically active basins to the west (Wagner- Consag and Upper Delfin basins) may have initiated synchronously with the now abandoned Tiburón- Tepoca-Altar basins to the east in the Sonora margin. In both basin systems the lower sequence (A) is marine mudstone-siltstone, has parallel reflectors and a largely uniform thickness that reaches up to1.5 km, and gradually pinches out toward the lateral margins. This suggests that the unit was deposited prior to their segmentation by transtensional faulting. Marine microfossils from borehole samples from sequence A in the Tiburón and Consag basins indicates middle Miocene (>11.2 Ma) proto-Gulf conditions. Sequence B conformably overlies sequence A, and is characterized by up to 2 km growth strata with a fanning geometry that show a clear genetic relationship to the major transtensional faults that control the segmentation of the two basin systems. Sequence C in the Tiburón and Tepoca basins is comparatively thin (<800 m) and includes several unconformities, but is much less affected by faulting. In contrast, sequence C in the active Wagner, Consag and Upper Delfin basin is a much thicker (up to 2 km) growth sequence with abundant volcanic intrusions. Marked variations in sequence C in the different basin systems clearly demonstrate a major westward shift of deformation and subsidence at this time. The modern depocenter in Wagner-Consag basins is controlled by the Consag and Wagner faults, which trend parallel to the north ~20 km apart, and show opposite normal offset. These two faults merge at an oblique angle (70°-50°, respectively) into the Cerro Prieto transform fault to the north and likely accommodate an important amount of dextral shear. To

  7. Litho stratigraphy of precambrian rocks in middle Xingu river basin -Altamira, Para state, Brazil

    International Nuclear Information System (INIS)

    Santos, M.V. dos; Sousa Filho, E.E. dos; Tassinari, C.C.G.

    1988-01-01

    The basement rocks from the Xingu river is divided into five litho stratigraphic units. They are broadly characterized by domains of ortho and para gneisses, volcano-sedimentary sequences, migmatites and by syntectonic and latetectonic granitoids. In addition acid to intermediate volcanics (Iriri formation) and several sub-volcanic granitic plutons (Maloquinha suite) also occur within the investigated area, as well as basic intrusions and minor arenous sediments covers, slightly metamorphosed. Geochronological studies carried out on the basement rocks and on the volcanics demonstrates an geologic evolution restricted to the trans Amazonian cycle (2.1 - 1.9 Ga). Sr isotopic evolution (high initial 87 Sr/ 86 Sr ratios) suggest that strong reworking of crustal material occurred at this time, in association with the tectonic evolution of the Maroni-Itacaiunas mobile belt related to the lower proterozoic, which borders the northern and northerneast part of the Archean central Amazonian province. (author)

  8. Concentrations and isotope ratios of mercury in sediments from shelf and continental slope at Campos Basin near Rio de Janeiro, Brazil.

    Science.gov (United States)

    Araujo, Beatriz Ferreira; Hintelmann, Holger; Dimock, Brian; Almeida, Marcelo Gomes; Rezende, Carlos Eduardo

    2017-07-01

    Mercury (Hg) may originate from both anthropogenic and natural sources. The measurement of spatial and temporal variations of Hg isotope ratios in sediments may enable source identification and tracking of environmental processes. In this study we establish the distribution of mercury concentrations and mercury isotope ratios in surface sediments of three transects along the continental shelf and slope in Campos Basin-RJ-Brazil. The shelf showed on average lower total Hg concentrations (9.2 ± 5.3 ng g -1 ) than the slope (24.6 ± 8.8 ng g -1 ). MMHg average concentrations of shelf 0.15 ± 0.12 ng g -1 and slope 0.13 ± 0.06 ng g -1 were not significantly different. Distinct differences in Hg isotope ratio signatures were observed, suggesting that the two regions were impacted by different sources of Hg. The shelf showed more negative δ 202 Hg and Δ 199 Hg values ranging from -0.59 to -2.19‰ and from -0.76 to 0.08‰, respectively. In contrast, the slope exhibited δ 202 Hg values from -0.29 to -1.82‰ and Δ 199 Hg values from -0.23 to 0.09‰. Mercury found on the shelf, especially along the "D" and "I" transects, is depleted in heavy isotopes resulting in more negative δ 202 Hg compared to the slope. Isotope ratios observed in the "D" and "I" shelf region are similar to Hg ratios commonly associated with plants and vegetation and very comparable to those detected in the estuary and adjoining mangrove forest, which suggests that Hg exported from rivers may be the dominating source of Hg in near coastal regions along the northern part of the shelf. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. A high 87Sr 86Sr mantle source for low alkali tholeiite, northern Great Basin

    Science.gov (United States)

    Mark, R.K.; Lee, Hu C.; Bowman, H.R.; Asaro, F.; McKee, E.H.; Coats, R.R.

    1975-01-01

    Olivine tholeiites, the youngest Tertiary units (about 8-11 m.y. old) at five widely spaced localities in northeastern Nevada, are geologically related to the basalts of the Snake River Plain, Idaho, to the north and are similar in major element and alkali chemistry to mid-ocean ridge basalts (MORB) and island arc tholeiites. The measured K (1250-3350 ppm), Rb (1??9-6??2 ppm) and Sr (140-240 ppm) concentrations overlap the range reported for MORB. Three of the five samples have low, unfractionated rare earth element (REE) patterns, the other two show moderate light-REE enrichment. Barium concentration is high and variable (100-780 ppm) and does not correlate with the other LIL elements. The rocks have 87Sr/86Sr = 0??7052-0??7076, considerably higher than MORB (~0??702-0??703). These samples are chemically distinct (i.e. less alkalic) from the olivine tholeiites from the adjacent Snake River Plain, but their Sr isotopic compositions are similar. They contain Sr that is distinctly more radiogenic than the basalts from the adjacent Great Basin. About 10 b.y. would be required for the mean measured Rb/Sr (~ 0??02) of these samples to generate, in a closed system, the radiogenic Sr they contain. The low alkali content of these basalts makes crustal contamination an unlikely mechanism. If the magma is uncontaminated, the time-averaged Rb/Sr of the source material must have been ~0??04. A significant decrease in Rb/Sr of the source material (a factor 2??) thus most probably occurred in the relatively recent (1??09 yr) past. Such a decrease of Rb/Sr in the mantle could accompany alkali depletion produced by an episode of partial melting and magma extraction. In contrast, low 87Sr 86Sr ratios indicate that the source material of the mid-ocean ridge basalts may have been depleted early in the Earth's history. ?? 1975.

  10. PERFORMANCE OF ‘TUXPAN VALENCIA’ SWEET ORANGE GRAFTED ONTO 14 ROOTSTOCKS IN NORTHERN BAHIA, BRAZIL

    Directory of Open Access Journals (Sweden)

    NATIANA DE OLIVEIRA FRANÇA

    Full Text Available ABSTRACT In the State of Bahia, Brazil, the citrus industry is located on the north coast with the prevalence of the combination ‘Pera’ sweet orange on ‘Rangpur’ lime. Scion-rootstock diversification may contribute to the increase of yield and the extension of harvest season, as long as to decrease the risk associated to abiotic and biotic stresses. Therefore, the performance of ‘Tuxpan Valencia’ sweet orange grafted onto 14 rootstocks was evaluated in Rio Real – BA. Planting was performed in 2006 under rainfed cultivation on cohesive ultisol and tree spacing of 6.0 m x 4.0 m. Tree size, yield and fruit quality were evaluated in the period of 2010-2014, in addition to tree survival at nine years old and drought tolerance in the field based on leaf wilting. In the evaluated conditions, ‘Sunki Tropical’ and ‘Sunki Maravilha’ mandarins led to the highest scion canopy volume. The highest accumulated yield in five harvests was recorded on ‘Santa Cruz Rangpur’ lime, ‘Volkamer’ lemon, ‘Riverside’ and ‘Indio’ citrandarins, ‘Sunki Tropical’ mandarin and the hybrid TSKC x (LCR x TR – 001. ‘Riverside’ and TSKFL x CTSW – 049 induced higher yield efficiency on the canopy. The rootstocks did not influence the tree survival nine years after planting except for lower survival of TSKFL x CTSW – 049. Drought tolerance was not affected either. Regarding to the fruit quality of ‘Tuxpan Valencia’, the rootstocks influenced the juice content, soluble solids and technological index with the citrandarins, ‘Santa Cruz Rangpur’ lime, ‘Volkamer’ lemon and ‘Sunki Tropical’ mandarin presenting higher performance in general.

  11. Effects of seasonality on drosophilids (Insecta, Diptera) in the northern part of the Atlantic Forest, Brazil.

    Science.gov (United States)

    Coutinho-Silva, R D; Montes, M A; Oliveira, G F; de Carvalho-Neto, F G; Rohde, C; Garcia, A C L

    2017-10-01

    Seasonality is an important aspect associated with population dynamic and structure of tropical insect assemblages. This study evaluated the effects of seasonality on abundance, richness, diversity and composition of an insect group, drosophilids, including species native to the Neotropical region and exotic ones. Three preserved fragments of the northern Atlantic Forest were surveyed, where temperatures are above 20 °C throughout the year and rainfall regimes define two seasons (dry and rainy). As opposed to other studies about arthropods in tropical regions, we observed that abundance of drosophilids was significantly higher in the dry season, possibly due to biological aspects and the colonization strategy adopted by the exotic species in these environments. Contrarily to abundance, we did not observe a seasonal pattern for richness. As for other parts of the Atlantic Forest, the most representative Neotropical species (Drosophila willistoni, D. sturtevanti, D. paulistorum and D. prosaltans) were significantly more abundant in the rainy season. Among the most abundant exotic species, D. malerkotliana, Zaprionus indianus and Scaptodrosophila latifasciaeformis were more importantly represented the dry season, while D. simulans was more abundant in the rainy period. The seasonality patterns exhibited by the most abundant species were compared to findings published in other studies. Our results indicate that exotic species were significantly more abundant in the dry season, while native ones exhibited an opposite pattern.

  12. Tetrapod tracks in Permo–Triassic eolian beds of southern Brazil (Paraná Basin

    Directory of Open Access Journals (Sweden)

    Heitor Francischini

    2018-05-01

    Full Text Available Tetrapod tracks in eolianites are widespread in the fossil record since the late Paleozoic. Among these ichnofaunas, the ichnogenus Chelichnus is the most representative of the Permian tetrapod ichnological record of eolian deposits of Europe, North America and South America, where the Chelichnus Ichnofacies often occurs. In this contribution, we describe five sets of tracks (one of which is preserved in cross-section, representing the first occurrence of Dicynodontipus and Chelichnus in the “Pirambóia Formation” of southern Brazil. This unit represents a humid desert in southwestern Pangea and its lower and upper contacts lead us to consider its age as Lopingian–Induan. The five sets of tracks studied were compared with several ichnotaxa and body fossils with appendicular elements preserved, allowing us to attribute these tracks to dicynodonts and other indeterminate therapsids. Even though the “Pirambóia Formation” track record is sparse and sub-optimally preserved, it is an important key to better understand the occupation of arid environments by tetrapods across the Permo–Triassic boundary.

  13. A New Species of Tiger Pleco Panaqolus (Siluriformes: Loricariidae from the Xingu Basin, Brazil.

    Directory of Open Access Journals (Sweden)

    Christian Andreas Cramer

    Full Text Available Panaqolus tankei is described from the Xingu River, Brazil. The new species is diagnosed from P. albomaculatus, P. dentex, P. nix, P. nocturnus, and P. koko by its color pattern consisting of dark and light diagonal bars on the body and bands on the fins (vs. body and fins without bars or bands; from P. albivermis, P. maccus, and P. purusiensis by the width of the dark bars being more or less the same of the light bars (vs. dark bars at least two or three times wider than light bars and from P. changae by the absence of vermiculation on the head (vs. vermiculation present on head. The new species differs from P. gnomus by the orientation of the bars from posterodorsal to anteroventral direction (vs. anterodorsal to posteroventral direction, and from P. claustellifer by the orientation of the bands in the dorsal fin that are not parallel to the margin (vs. parallel to the margin. The barcoding region (COI was sequenced for the new species, sequences were deposited in GenBank and were compared with congeners from other drainages. With regard to the current construction of a hydroelectric power plant (a so-called mega dam in the Xingu River, herewith we increase knowledge of the river Xingu's ichthyofauna and, thus improve the assessment of the impacts of that construction on the river.

  14. Stratigraphic and sedimentary evidences for development of Aptian intrashelf basin in the structural Zagros zone, northern Fars Platform

    Directory of Open Access Journals (Sweden)

    Neda Khoshfam

    2016-12-01

    Therefore despite previous visions, the Fars platform was not a monolith shallow platform. In addition, except Kazhdumi intrashelf basin, there were other deep and local intrashelf basins which were developed within the Fars platform.

  15. Neogene vegetation development in the Amazon Basin: evidence from marine well-2, Foz do Amazonas (Brazil)

    Science.gov (United States)

    Bogota-Angel, Raul; Chemale Junior, Farid; Davila, Roberto; Soares, Emilson; Pinto, Ricardo; Do Carmo, Dermeval; Hoorn, Carina

    2014-05-01

    Origen and development of the highly diverse Amazon tropical forest has mostly been inferred from continental sites. However, sediment records in the marine Foz do Amazonas Basin can provide important information to better understand the influence of the Andes uplift and climate change on its plant biomes evolution since the Neogene. Sediment analyses of samples from BP-Petrobras well 1 and 2, drilled in the Amazon Fan, allowed to infer the onset of the transcontinental Amazon river and the fan phase during the middle to late Miocene (c. 10.5 Ma). As part of the CLIMAMAZON research programme we performed pollen analysis on the 10.5 to 0.4 Ma time interval. 76 ditch cutting samples of the upper 4165 m sediments of well 2 permitted us to infer changes in floral composition in the Amazon Basin. The palynological spectra across this interval (nannofossil based age model) include pollen, fern spores, dinocysts and foram lignings. When possible pollen and fern spores were grouped in four vegetation types: estuarine, tropical, mountain forest and high mountain open treeless vegetation. Pollen is generally corroded and reflects the effects of sediment transportation while reworked material is also common. Good pollen producers such as Poaceae, Asteraceae and Cyperaceae are common and reflect indistinctive vegetation types particularly those associated to riverine systems. Rhizophora/Zonocostites spp. indicate "close-distance" mangrove development. Tropical forest biomes are represented by pollen that resemble Moraceae-Urticaceae, Melastomataceae-Combretaceae, Sapotaceae, Alchornea, Euphorbiaceae, Rubiaceae, Bignoniaceae, Mauritia and Arecaceae. Myrica, and particularly sporadic occurrences of fossil fern spores like Lophosoria, and Cyathea suggest the development of a moist Andean forest in areas above 1000 m. First indicators of high altitudes appear in the last part of late Miocene with taxa associated to current Valeriana and particularly Polylepis, a neotropical taxon

  16. Determining the source and genetic fingerprint of natural gases using noble gas geochemistry: a northern Appalachian Basin case study

    Science.gov (United States)

    Hunt, Andrew G.; Darrah, Thomas H.; Poreda, Robert J.

    2012-01-01

    Silurian and Devonian natural gas reservoirs present within New York state represent an example of unconventional gas accumulations within the northern Appalachian Basin. These unconventional energy resources, previously thought to be noneconomically viable, have come into play following advances in drilling (i.e., horizontal drilling) and extraction (i.e., hydraulic fracturing) capabilities. Therefore, efforts to understand these and other domestic and global natural gas reserves have recently increased. The suspicion of fugitive mass migration issues within current Appalachian production fields has catalyzed the need to develop a greater understanding of the genetic grouping (source) and migrational history of natural gases in this area. We introduce new noble gas data in the context of published hydrocarbon carbon (C1,C2+) (13C) data to explore the genesis of thermogenic gases in the Appalachian Basin. This study includes natural gases from two distinct genetic groups: group 1, Upper Devonian (Marcellus shale and Canadaway Group) gases generated in situ, characterized by early mature (13C[C1  C2][13C113C2]: –9), isotopically light methane, with low (4He) (average, 1  103 cc/cc) elevated 4He/40Ar and 21Ne/40Ar (where the asterisk denotes excess radiogenic or nucleogenic production beyond the atmospheric ratio), and a variable, atmospherically (air-saturated–water) derived noble gas component; and group 2, a migratory natural gas that emanated from Lower Ordovician source rocks (i.e., most likely, Middle Ordovician Trenton or Black River group) that is currently hosted primarily in Lower Silurian sands (i.e., Medina or Clinton group) characterized by isotopically heavy, mature methane (13C[C1 – C2] [13C113C2]: 3), with high (4He) (average, 1.85  103 cc/cc) 4He/40Ar and 21Ne/40Ar near crustal production levels and elevated crustal noble gas content (enriched 4He,21Ne, 40Ar). Because the release of each crustal noble gas (i.e., He, Ne, Ar

  17. Tectonic and climatic controls on continental depositional facies in the Karoo Basin of northern Natal, South Africa

    Science.gov (United States)

    Turner, Brian R.

    1986-02-01

    The eastern Karoo Basin, South Africa, contains a thick sequence of terrigenous clastic sediments comprising a meanderbelt facies, braided channel facies divided into coarse and fine subfacies, fluviolacustrine facies and aeolian facies. Depositional trends and changes in fluvial style reflect a progressive increase in aridity of the climate under stable tectonic conditions, interrupted by two phases of source area tectonism and the development of fine and coarse clastic wedges of the braided channel subfacies; the latter signifying a short interlude of cool, wet conditions. The fine braided channel subfacies occurs in the upper part of the meanderbelt facies, which was deposited by ephemeral, meandering mixed-load streams of variable discharge and sinuosity, under dry, semi-arid climatic conditions. These deposited complex, internally discordant channel sands and well-developed levee deposits. Following deposition of the coarse braided channel subfacies semi-arid conditions returned and fluvial deposition was dominated by ephemeral, straight to slightly sinuous mixed load streams characterised by simple channel sand bodies. As the aridity of the climate increased, the streams became more localised and carried an increasing proportion of fines. Interbedded with and overlying the fluvial deposits is a mudstone-dominated lacustrine sequence grading up into aeolian sands suggesting a playa lake-type situation. The general absence of evaporites from these sediments is attributed to the fresh nature of the lake waters, as evidenced by the freshwater aquatic organisms and clay-mineral suite, the lack of adequate inflow for solute accumulation and the removal of dust impregnated by salts from the surface of the dry lake bed during the dry season by superheated, upward-spiralling columns of air. Broadly similar environments to the fluvio-lacustrine and aeolian facies sequence are to be found in the Lake Eyre Basin of central Australia and the Okavango "delta" of northern

  18. Growth Normal Faulting at the Western Edge of the Metropolitan Taipei Basin since the Last Glacial Maximum, Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Chih-Tung Chen

    2010-01-01

    Full Text Available Growth strata analysis is an useful tool in understanding kinematics and the evolution of active faults as well as the close relationship between sedimentation and tectonics. Here we present the Shanchiao Fault as a case study which is an active normal fault responsible for the formation of the 700-m-thick late Quaternary deposits in Taipei Basin at the northern tip of the Taiwan mountain belt. We compiled a sedimentary record, particularly the depositional facies and their dated ages, at three boreholes (SCF-1, SCF-2 and WK-1, from west to east along the Wuku Profile that traverses the Shanchiao Fault at its central segment. By incorporating the global sea level change curve, we find that thickness changes of sediments and changes of depositional environments in the Wuku area are in a good agreement with a rapid sea level rise since the Last Glacial Maximum (LGM of about 23 ka. Combining depositional facies changes and their ages with their thickness, we are able to introduce a simple back-stripping method to reconstruct the evolution of growing strata across the Shanchiao Fault since the LGM. We then estimate the vertical tectonic slip rate since 23 ka, which exhibits 2.2 mm yr-1 between SCF-2 and WK-1 and 1.1 mm yr-1 between SCF-1 and SCF-2. We also obtain the Holocene tectonic subsidence rate of 2.3 mm yr-1 at WK-1 and 0.9 mm yr-1 at SCF-2 since 8.4 ka. We thus conclude that the fault zone consists of a high-angle main fault to the east between SCF-2 and WK-1 and a western lower-angle branch fault between SCF-1 and SCF-2, resembling a tulip structure developed under sinistral transtensional tectonism. We find that a short period of 600-yr time span in 9 - 8.4 ka shows important tectonic subsidence of 7.4 and 3.3 m for the main and branch fault, respectively, consistent with possible earthquake events proposed by previous studies during that time. A correlation between geomorphology and subsurface geology in the Shanchiao Fault zone shows

  19. Hydro-Economic Modeling with Minimum Data Requirements: An Application to the São Francisco River Basin, Brazil

    Science.gov (United States)

    Torres, M.; Maneta, M.; Vosti, S.; Wallender, W.; Howitt, R.

    2008-12-01

    Policymakers have been charged with the efficient, equitable, and sustainable use of water resources of the São Francisco River Basin (SFRB), Brazil, and also with the promotion of economic growth and the reduction of poverty within the basin. To date, policymakers lack scientific evidence on the potential consequences for growth, poverty alleviation or environmental sustainability of alternative uses of water resources. To address these key knowledge gaps, we have linked a hydrologic and an economic model of agriculture to investigate how economic decisions affect available water, and vice versa. More specifically, the models are used to predict the effects of the application of Brazilian federal surface water use policies on farmer's net revenues and on the hydrologic system. The Economic Model of Agriculture. A spatially explicit, farm-level model capable of accommodating a broad array of farm sizes and farm/farmer characteristics is developed and used to predict the effects of alternative water policies and neighbors' water use patterns on crop mix choice. A production function comprised of seven categories of non-water-related inputs used in agriculture (land, fertilizers, pesticides, seeds, hired labor, family labor and machinery) and four water-related inputs used in agriculture (applied water, irrigation labor, irrigation capital and energy) is estimated. The parameters emerging from this estimated production function are then introduced into a non-linear, net revenue maximization positive mathematical programming algorithm that is used for simulations. The Hydrological Model. MIKE Basin, a semi-distributed hydrology model, is used to calculate water budgets for the SFRB. MIKE Basin calculates discharge at selected nodes by accumulating runoff down the river network; it simulates reservoirs using stage-area-storage and downstream release rule curves. The data used to run the model are discharge to calculate local runoff, precipitation, reference ET, crop

  20. The integration of gravity, magnetic and seismic data in delineating the sedimentary basins of northern Sinai and deducing their structural controls

    Science.gov (United States)

    Selim, El Sayed Ibrahim

    2016-01-01

    The Sinai Peninsula is a part of the Sinai sub-plate that located between the southeast Nubian-Arabian shield and the southeastern Mediterranean northward. The main objectives of this investigation are to deduce the main sedimentary basin and its subdivisions, identify the subsurface structural framework that affects the study area and determine the thickness of sedimentary cover of the basement surface. The total intensity magnetic map, Bouguer gravity map and seismic data were used to achieve the study aims. Structural interpretation of the gravity and magnetic data were done by applying advanced processing techniques. These techniques include; Reduce to the pole (RTP), Power spectrum, Tile derivative and Analytical Signal techniques were applied on gravity and magnetic data. Two dimensional gravity and magnetic modeling and interpretation of seismic sections were done to determine the thickness of sedimentary cover of the study area. The integration of our interpretation suggests that, the northern Sinai area consists of elongated troughs that contain many high structural trends. Four major structural trends have been identified, that, reflecting the influence of district regional tectonic movements. These trends are: (1) NE-SW trend; (2) NNW-SSE trend; (3) ENE-WSW trend and (4) WNW-ESE trend. There are also many minor trends, E-W, NW-SE and N-S structural trends. The main sedimentary basin of North Sinai is divided into four sub-basins; (1) Northern Maghara; (2) Northeastern Sinai; (3) Northwestern Sinai and (4) Central Sinai basin. The sedimentary cover ranges between 2 km and 7 km in the northern part of the study area.

  1. REPTILE SPECIES COMPOSITION IN THE MIDDLE GURGUÉIA AND COMPARISON WITH INVENTORIES IN THE EASTERN PARNAÍBA RIVER BASIN, STATE OF PIAUÍ, BRAZIL

    Directory of Open Access Journals (Sweden)

    CLÁUDIA RENATA MADELLA-AURICCHIO

    Full Text Available ABSTRACT The reptile diversity of the Middle Gurguéia River Basin in southern Piauí, Brazil, is little known. The rapid expansion of agriculture in the region is converting the Cerrado and Caatinga into large farming areas, which threatens biodiversity and hastens its loss. In this study, 68 specimens of reptiles from a university collection were examined, comprising 29 species: ten lizards, one amphisbaenian, 15 snakes, two turtles and one crocodilian. They were collected from five locations in the Middle Gurguéia Basin, a region not previously evaluated for reptiles. The most abundant species is a member of Tropidurus. Comparison with eight other areas in the eastern Parnaíba Basin indicated that the diversity of reptiles in the Middle Gurguéia is similar to that in other Caatinga-Cerrado ecotone areas. The reptile assemblage in the eastern Parnaíba Basin comprises 100 species of reptiles: 39 lizards, five amphisbaenians, 50 snakes, four chelonians and two crocodilians. This study expanded the known distributions of some reptiles and recorded the first occurrence of Helicops leopardinus (Schlegel, 1837 for Piauí. A cluster analysis showed that the reptile composition concords with the habitat where species were found, i.e. Cerrado, Caatinga or ecotone. Studies that associate habitat structure with each species are essential to propose efficient strategies for reptile management and conservation for the entire Parnaíba River Basin, mostly in areas that are not yet protected.

  2. First record of Annonaceae wood for the Neogene of South America, Amazon Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Emilio Alberto Amaral Soares

    Full Text Available ABSTRACT: The relief of the regions of Manaus and Itacoatiara, Central Amazon, is supported by Neogene siliciclastic rocks, bounded at the base and top by lateritic paleosols and covered by quaternary sedimentary deposits from the Solimões-Amazon river system. This unit is informally assigned to the Novo Remanso Formation, consists of usually reddish and ferruginized sandstones, conglomerates and pelites, with few identified fossil records, a fact that has hindered its stratigraphic position, and the paleoenvironmental reconstruction of the last phase of the Amazon Basin settling. This study describes, for the first time, the occurrence of fossil wood in outcroppings of the left bank of the Amazon River, where anatomical and morphological data has enabled its characterization to the species level. Thus, the data marks the record of the Annonaceae in South America, as well as the depositional processes related to incorporation of organic material in the sandy layer and the fossilization processes that allowed its preservation. In an unprecedented way, this study has described Duguetiaxylon amazonicum nov. gen and sp. and provided information on the anatomical and systematic character, as well as data on plant-insect interaction, and a better understanding of the family.

  3. Marine controlled source electromagnetic (mCSEM) detects hydrocarbon reservoirs in the Santos Basin - Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Buonora, Marco Polo Pereira; Rodrigues, Luiz Felipe [PETROBRAS, Rio de Janeiro, RJ (Brazil); Zerilli, Andrea; Labruzzo, Tiziano [WesternGeco, Houston, TX (United States)

    2008-07-01

    In recent years marine Controlled Source Electromagnetic (mCSEM) has driven the attention of an increasing number of operators due to its sensitivity to map resistive structures, such as hydrocarbon reservoirs beneath the ocean floor and successful case histories have been reported. The Santos basin mCSEM survey was performed as part of a technical co-operation project between PETROBRAS and Schlumberger to assess the integration of selected deep reading electromagnetic technologies into the full cycle of oil field exploration and development. The survey design was based on an in-depth sensitivity study, built on known reservoirs parameters, such as thickness, lateral extent, overburden and resistivities derived from seismic and well data. In this context, the mCSEM data were acquired to calibrate the technology over the area's known reservoirs, quantify the resistivity anomalies associated with those reservoirs, with the expectation that new prospective locations could be found. We show that the mCSEM response of the known reservoirs yields signatures that can be clearly imaged and accurately quantified and there are evident correlations between the mCSEM anomalies and the reservoirs. (author)

  4. Endocrine disruptors in water filters used in the Rio dos Sinos Basin region, Southern Brazil

    Directory of Open Access Journals (Sweden)

    CM Furtado

    Full Text Available The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were analysed. Using the developed methodology, it was possible to detect and comparatively quantify selected EDCs in all studied samples, which indicates the presence of these contaminants in drinking water from different sources.

  5. Late quaternary dynamics in the Madeira river basin, southern Amazonia (Brazil, as revealed by paleomorphological analysis

    Directory of Open Access Journals (Sweden)

    Ericson H. Hayakawa

    2015-03-01

    Full Text Available Ancient drainage systems are being increasingly documented in the Amazon basin and their characterization is crucial for reconstructing fluvial evolution in this area. Fluvial morphologies, including elongate belts, are well preserved along the Madeira River. Digital Elevation Model from the Shuttle Radar Topography Mission favored the detection of these features even where they are covered by dense rainforest. These paleomorphologies are attributed to the shifting position of past tributaries of the Madeira River through avulsions. These radial paleodrainage networks produced fan-shaped morphologies that resemble distributary megafans. Distinguishing avulsive tributary systems from distributary megafans in the sedimentary record is challenging. Madeira´s paleodrainage reveals the superposition of tributary channels formed by multiple avulsions within a given time period, rather than downstream bifurcation of coexisting channels. Channel avulsion in this Amazonian area during the late Quaternary is related to tectonics due to features as: (i straight lineaments coincident with fault directions; (ii northeastward tilting of the terrain with Quaternary strata; and (iii several drainage anomalies, including frequent orthogonal drainage inflections. These characteristics altogether lead to propose that the radial paleodrainage present at the Madeira River margin results from successive avulsions of tributary channels over time due to tectonics.

  6. Rescaled range analysis of streamflow records in the São Francisco River Basin, Brazil

    Science.gov (United States)

    Araujo, Marcelo Vitor Oliveira; Celeste, Alcigeimes B.

    2018-01-01

    Hydrological time series are sometimes found to have a distinctive behavior known as long-term persistence, in which subsequent values depend on each other even under very large time scales. This implies multiyear consecutive droughts or floods. Typical models used to generate synthetic hydrological scenarios, widely used in the planning and management of water resources, fail to preserve this kind of persistence in the generated data and therefore may have a major impact on projects whose design lives span for long periods of time. This study deals with the evaluation of long-term persistence in streamflow records by means of the rescaled range analysis proposed by British engineer Harold E. Hurst, who first observed the phenomenon in the mid-twentieth century. In this paper, Hurst's procedure is enhanced by a strategy based on statistical hypothesis testing. The case study comprises the six main hydroelectric power plants located in the São Francisco River Basin, part of the Brazilian National Grid. Historical time series of inflows to the major reservoirs of the system are investigated and 5/6 sites show significant persistence, with values for the so-called Hurst exponent near or greater than 0.7, i.e., around 40% above the value 0.5 that represents a white noise process, suggesting that decision makers should take long-term persistence into consideration when conducting water resources planning and management studies in the region.

  7. Measurement and modeling of wind waves at the northern coast of Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    José Henrique G. M. Alves

    2001-01-01

    Full Text Available Directional measurements of wind-wave spectra made during the year of 1996 are used in a preliminary investigation of the wind-wave climate and its transformation at the São Francisco do Sul island, northern coast of the Santa Catarina state. Four major sea states and associated meteorological conditions are identified through analyses of joint distributions of observed wave parameters. Transformations of these main sea-state patterns due to refraction and shoaling are investigated through a numerical modeling approach that allows the reconstruction of the wave field within extensive coastal areas, using single point measurements of the wave spectrum in shallow waters. Cross-validation of measured and reconstructed spectra at the study site yield consistent results, suggesting that the proposed methodology works well for the São Francisco do Sul coast.Medições do espectro direcional de ondas geradas pelo vento realizadas em 1996 são utilizadas em uma investigação preliminar do clima de ondas no litoral norte de Santa Catarina, Brasil. Quatro estados de mar predominantes são identificados, em conjunto com os padrões meteorológicos associados a sua ocorrência, através de análises estatísticas. As transformações desses quatro estados de mar devido a refraçâo e empinamento são investigadas através de modelos numéricos, que permitem obter estimativas do campo de ondas em áreas extensas a partir de medições pontuais feitas em águas rasas. Comparações entre espectros medidos e modelados produzem resultados consistentes, sugerindo que a metodologia proposta é válida para a costa de São Francisco do Sul.

  8. High-Resolution Subsurface Imaging and Stratigraphy of Quaternary Deposits, Marapanim Estuary, Northern Brazil

    Science.gov (United States)

    Silva, C. A.; Souza Filho, P. M.; Gouvea Luiz, J.

    2007-05-01

    The Marapanim estuary is situated in the Para Coastal Plain, North Brazil. It is characterized by an embayed coastline developed on Neogene and Quaternary sediments of the Barreiras and Pos-Barreiras Group. This system is strongly influenced by macrotidal regimes with semidiurnal tides and by humid tropical climate conditions. The interpretation of GPR-reflections presented in this paper is based on correlation of the GPR signal with stratigraphic data acquired on the coastal plain through five cores that were taken along GPR survey lines from the recent deposits and outcrops observed along to the coastal area. The profiles were obtained using a Geophysical Survey Systems Inc., Model YR-2 GPR, with monostatic 700 MHz antenna that permitted to get records of subsurface deposits at 20m depth. Were collected 54 radar sections completing a total of 4.360m. The field data were analyzed using a RADAN software and applying different filters. The interpretation of radar facies following the principles of seismic stratigraphy that permitted analyze the sedimentary facies and facies architecture in order to understand the lithology, depositional environments and stratigraphic evolution of this sedimentary succession as well as to leading to a more precise stratigraphic framework for the Neogene to Quaternary deposits at Marapanim coastal plain. Facies characteristics and sedimentologic analysis (i.e., texture, composition and structure aspects) were investigated from five cores collected through a Rammkernsonde system. The locations were determined using a Global Positioning System. Remote sensing images (Landsat-7 ETM+ and RADARSAT-1 Wide) and SRTM elevation data were used to identify and define the distribution of the different morphologic units. The Coastal Plain extends west-east of the mouth of the Marapanim River, where were identified six morphologic units: paleodune, strand plain, recent coastal dune, macrotidal sandy beach, mangrove and salt marsh. The integration

  9. Nesting habits of Centris (Hemisiella) dichrootricha (Hymenoptera: Apidae) in the Northern Cerrado of Brazil.

    Science.gov (United States)

    Carvalho, Gracy C A; Carreira, Léa M M; Rêgo, Márcia M C; Albuquerque, Patricia M C

    2016-09-01

    The Neotropical bee Centris (Hemisiella) dichrootricha is a solitary bee that nests in pre-existing cavities that occur in the rain forest. This study describes the nesting biology of C. dichrootricha and its preference for nesting in Cerrado and gallery forest habitats. The study was conducted from January 2012 and December 2013, in Mirador State Park in the municipality of Formosa da Serra Negra, Maranhão State, Brazil. For this, wooden trap-nests of 6, 8, 10, 12, 14 and 16 mm in diameter were used; a total of 300 trap-nests were placed in the gallery forest and Cerrado areas, respectively. Traps were monitored monthly and all completed nests were collected and replaced with empty ones. The nests were then taken to the laboratory to analyze bee development and emergence, nests characteristics and parasites presence. The species used 29 of the trap-nests, which had diameters of 8, 10, 12 and 14 mm. A total of 87 C. dichrootricha specimens emerged. The nests were parasitized by two bee species, Mesocheira bicolor (Apinae) and Coelioxys sp. (Megachilinae), and one fly species, Antrax sp. (Diptera). The highest nesting incidence of 72.4 % was observed in the gallery forest, whereas only 27.6 % in the Cerrado; this difference in habitat use was significant (χ² = 5.56; p pollen types that belonged to six families. Pollen of the family Malpighiaceae was most frequently used, with four species represented (Byrsonima crassifolia, B. rotunda, B. spicata and Heteropterys sp.). C. dichrootricha showed a preference for nesting in cavities of various diameters in gallery forest sites. The present study provides a novel description of the nesting habits and biology of C. dichrootricha in habitats of Central/Southern Maranhão. C. dichrootricha primarily used resources from the Cerrado, including soil to build their nests, pollen and floral oils; we concluded that gallery forest and Cerrado areas are intrinsically related to the maintenance of local populations of this

  10. Spatial variability of soil carbon stock in the Urucu river basin, Central Amazon-Brazil.

    Science.gov (United States)

    Ceddia, Marcos Bacis; Villela, André Luis Oliveira; Pinheiro, Érika Flávia Machado; Wendroth, Ole

    2015-09-01

    The Amazon Forest plays a major role in C sequestration and release. However, few regional estimates of soil organic carbon (SOC) stock in this ecoregion exist. One of the barriers to improve SOC estimates is the lack of recent soil data at high spatial resolution, which hampers the application of new methods for mapping SOC stock. The aims of this work were: (i) to quantify SOC stock under undisturbed vegetation for the 0-30 and the 0-100 cm under Amazon Forest; (ii) to correlate the SOC stock with soil mapping units and relief attributes and (iii) to evaluate three geostatistical techniques to generate maps of SOC stock (ordinary, isotopic and heterotopic cokriging). The study site is located in the Central region of Amazon State, Brazil. The soil survey covered the study site that has an area of 80 km(2) and resulted in a 1:10,000 soil map. It consisted of 315 field observations (96 complete soil profiles and 219 boreholes). SOC stock was calculated by summing C stocks by horizon, determined as a product of BD, SOC and the horizon thickness. For each one of the 315 soil observations, relief attributes were derived from a topographic map to understand SOC dynamics. The SOC stocks across 30 and 100 cm soil depth were 3.28 and 7.32 kg C m(-2), respectively, which is, 34 and 16%, lower than other studies. The SOC stock is higher in soils developed in relief forms exhibiting well-drained soils, which are covered by Upland Dense Tropical Rainforest. Only SOC stock in the upper 100 cm exhibited spatial dependence allowing the generation of spatial variability maps based on spatial (co)-regionalization. The CTI was inversely correlated with SOC stock and was the only auxiliary variable feasible to be used in cokriging interpolation. The heterotopic cokriging presented the best performance for mapping SOC stock. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Geochemical behavior and dissolved species control in acid sand pit lakes, Sepetiba sedimentary basin, Rio de Janeiro, SE - Brazil

    Science.gov (United States)

    Marques, Eduardo D.; Sella, Sílvia M.; Bidone, Edison D.; Silva-Filho, Emmanoel V.

    2010-12-01

    This work shows the influence of pluvial waters on dissolved components and mineral equilibrium of four sand pit lakes, located in the Sepetiba sedimentary basin, SE Brazil. The sand mining activities promote sediment oxidation, lowering pH and increasing SO 4 contents. The relatively high acidity of these waters, similar to ore pit lakes environment and associated acid mine drainage, increases weathering rate, especially of silicate minerals, which produces high Al concentrations, the limiting factor for fish aquaculture. During the dry season, basic cations (Ca, Mg, K and Na), SiO 2 and Al show their higher values due to evapoconcentration and pH are buffered. In the beginning of the wet season, the dilution factor by rainwater increases SO 4 and decreases pH values. The aluminum monomeric forms (Al(OH) 2+ and Al(OH) 2+), the most toxic species for aquatic organisms, occur during the dry season, while AlSO 4+ species predominate during the wet season. Gibbsite, allophane, alunite and jurbanite are the reactive mineral phases indicated by PHREEQC modeling. During the dry season, hydroxialuminosilicate allophane is the main phase in equilibrium with the solution, while the sulphate salts alunite and jurbanite predominate in the rainy season due to the increasing of SO 4 values. Gibbsite is also in equilibrium with sand pit lakes waters, pointing out that hydrolysis reaction is a constant process in the system. Comparing to SiO 2, sulphate is the main Al retriever in the pit waters because the most samples (alunite and jurbanite) are in equilibrium with the solution in both seasons. This Al hydrochemical control allied to some precaution, like pH correction and fertilization of these waters, allows the conditions for fishpond culture. Equilibrium of the majority samples with kaolinite (Ca, Mg, Na diagrams) and primary minerals (K diagram) points to moderate weathering rate in sand pit sediments, which cannot be considered for the whole basin due to the anomalous

  12. Extensive summer water pulses do not necessarily lead to canopy growth of Great Basin and northern Mojave Desert shrubs.

    Science.gov (United States)

    Snyder, K A; Donovan, L A; James, J J; Tiller, R L; Richards, J H

    2004-10-01

    Plant species and functionally related species groups from arid and semi-arid habitats vary in their capacity to take up summer precipitation, acquire nitrogen quickly after summer precipitation, and subsequently respond with ecophysiological changes (e.g. water and nitrogen relations, gas exchange). For species that respond ecophysiologically, the use of summer precipitation is generally assumed to affect long-term plant growth and thus alter competitive interactions that structure plant communities and determine potential responses to climate change. We assessed ecophysiological and growth responses to large short-term irrigation pulses over one to three growing seasons for several widespread Great Basin and northern Mojave Desert shrub species: Chrysothamnus nauseosus, Sarcobatus vermiculatus, Atriplex confertifolia, and A. parryi. We compared control and watered plants in nine case studies that encompassed adults of all four species, juveniles for three of the species, and two sites for two of the species. In every comparison, plants used summer water pulses to improve plant water status or increase rates of functioning as indicated by other ecophysiological characters. Species and life history stage responses of ecophysiological parameters (leaf N, delta15N, delta13C, gas exchange, sap flow) were consistent with several previous short-term studies. However, use of summer water pulses did not affect canopy growth in eight out of nine comparisons, despite the range of species, growth stages, and site conditions. Summer water pulses affected canopy growth only for C. nauseosus adults. The general lack of growth effects for these species might be due to close proximity of groundwater at these sites, co-limitation by nutrients, or inability to respond due to phenological canalization. An understanding of the connections between short-term ecophysiological responses and growth, for different habitats and species, is critical for determining the significance of

  13. Scenarios for shale gas development and their related land use impacts in the Baltic Basin, Northern Poland

    International Nuclear Information System (INIS)

    Baranzelli, Claudia; Vandecasteele, Ine; Ribeiro Barranco, Ricardo; Mari i Rivero, Ines; Pelletier, Nathan; Batelaan, Okke; Lavalle, Carlo

    2015-01-01

    Scenarios for potential shale gas development were modelled for the Baltic Basin in Northern Poland for the period 2015–2030 using the land allocation model EUCS100. The main aims were to assess the associated land use requirements, conflicts with existing land use, and the influence of legislation on the environmental impact. The factors involved in estimating the suitability for placement of shale gas well pads were analysed, as well as the potential land and water requirements to define 2 technology-based scenarios, representing the highest and lowest potential environmental impact. 2 different legislative frameworks (current and restrictive) were also assessed, to give 4 combined scenarios altogether. Land consumption and allocation patterns of well pads varied substantially according to the modelled scenario. Potential landscape fragmentation and conflicts with other land users depended mainly on development rate, well pad density, existing land-use patterns, and geology. Highly complex landscapes presented numerous barriers to drilling activities, restricting the potential development patterns. The land used for shale gas development could represent a significant percentage of overall land take within the shale play. The adoption of appropriate legislation, especially the protection of natural areas and water resources, is therefore essential to minimise the related environmental impact. -- Highlights: •A range of scenarios for shale gas development in Poland were modelled. •The impact in terms of land take and competition for land was assessed. •Of land used for industrial purposes, 7–12% was attributed to shale gas extraction. •If unregulated, 24% of well pads were developed within protected areas. •The legislative framework can have a major influence on overall environmental impact

  14. Genetic Types and Source of the Upper Paleozoic Tight Gas in the Hangjinqi Area, Northern Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Xiaoqi Wu

    2017-01-01

    Full Text Available The molecular and stable isotopic compositions of the Upper Paleozoic tight gas in the Hangjinqi area in northern Ordos Basin were investigated to study the geochemical characteristics. The tight gas is mainly wet with the dryness coefficient (C1/C1–5 of 0.853–0.951, and δ13C1 and δ2H-C1 values are ranging from -36.2‰ to -32.0‰ and from -199‰ to -174‰, respectively, with generally positive carbon and hydrogen isotopic series. Identification of gas origin indicates that tight gas is mainly coal-type gas, and it has been affected by mixing of oil-type gas in the wells from the Shilijiahan and Gongkahan zones adjacent to the Wulanjilinmiao and Borjianghaizi faults. Gas-source correlation indicates that coal-type gas in the Shiguhao zone displays distal-source accumulation. It was mainly derived from the coal-measure source rocks in the Upper Carboniferous Taiyuan Formation (C3t and Lower Permian Shanxi Formation (P1s, probably with a minor contribution from P1s coal measures from in situ Shiguhao zone. Natural gas in the Shilijiahan and Gongkahan zones mainly displays near-source accumulation. The coal-type gas component was derived from in situ C3t-P1s source rocks, whereas the oil-type gas component might be derived from the carbonate rocks in the Lower Ordovician Majiagou Formation (O1m.

  15. A systematic approach for watershed ecological restoration strategy making: An application in the Taizi River Basin in northern China.

    Science.gov (United States)

    Li, Mengdi; Fan, Juntao; Zhang, Yuan; Guo, Fen; Liu, Lusan; Xia, Rui; Xu, Zongxue; Wu, Fengchang

    2018-05-15

    Aiming to protect freshwater ecosystems, river ecological restoration has been brought into the research spotlight. However, it is challenging for decision makers to set appropriate objectives and select a combination of rehabilitation acts from numerous possible solutions to meet ecological, economic, and social demands. In this study, we developed a systematic approach to help make an optimal strategy for watershed restoration, which incorporated ecological security assessment and multi-objectives optimization (MOO) into the planning process to enhance restoration efficiency and effectiveness. The river ecological security status was evaluated by using a pressure-state-function-response (PSFR) assessment framework, and MOO was achieved by searching for the Pareto optimal solutions via Non-dominated Sorting Genetic Algorithm II (NSGA-II) to balance tradeoffs between different objectives. Further, we clustered the searched solutions into three types in terms of different optimized objective function values in order to provide insightful information for decision makers. The proposed method was applied in an example rehabilitation project in the Taizi River Basin in northern China. The MOO result in the Taizi River presented a set of Pareto optimal solutions that were classified into three types: I - high ecological improvement, high cost and high benefits solution; II - medial ecological improvement, medial cost and medial economic benefits solution; III - low ecological improvement, low cost and low economic benefits solution. The proposed systematic approach in our study can enhance the effectiveness of riverine ecological restoration project and could provide valuable reference for other ecological restoration planning. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Innovative Methodology for Detection of Fracture-Controlled Sweet Spots in the Northern Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Robert Jacobi; John Fountain; Stuart Loewenstein; Edward DeRidder; Bruce Hart

    2007-03-31

    For two consecutive years, 2004 and 2005, the largest natural gas well (in terms of gas flow/day) drilled onshore USA targeted the Ordovician Trenton/Black River (T/BR) play in the Appalachian Basin of New York State (NYS). Yet, little data were available concerning the characteristics of the play, or how to recognize and track T/BR prospects across the region. Traditional exploration techniques for entry into a hot play were of limited use here, since existing deep well logs and public domain seismic were almost non-existent. To help mitigate this problem, this research project was conceived with two objectives: (1) to demonstrate that integrative traditional and innovative techniques could be used as a cost-effective reconnaissance exploration methodology in this, and other, areas where existing data in targeted fracture-play horizons are almost non-existent, and (2) determine critical characteristics of the T/BR fields. The research region between Seneca and Cayuga lakes (in the Finger Lakes of NYS) is on strike and east of the discovery fields, and the southern boundary of the field area is about 8 km north of more recently discovered T/BR fields. Phase I, completed in 2004, consisted of integrating detailed outcrop fracture analyses with detailed soil gas analyses, lineaments, stratigraphy, seismic reflection data, well log data, and aeromagnetics. In the Seneca Lake region, Landsat lineaments (EarthSat, 1997) were coincident with fracture intensification domains (FIDs) and minor faults observed in outcrop and inferred from stratigraphy. Soil gas anomalies corresponded to ENE-trending lineaments and FIDs. N- and ENE-trending lineaments were parallel to aeromagnetic anomalies, whereas E-trending lineaments crossed aeromagnetic trends. 2-D seismic reflection data confirmed that the E-trending lineaments and FIDs occur where shallow level Alleghanian salt-cored thrust-faulted anticlines occur. In contrast, the ENE-trending FIDs and lineaments occur where Iapetan

  17. Late Paleozoic paleofjord in the southernmost Parana Basin (Brazil): Geomorphology and sedimentary fill

    Science.gov (United States)

    Tedesco, Julia; Cagliari, Joice; Coitinho, Julia dos Reis; da Cunha Lopes, Ricardo; Lavina, Ernesto Luiz Correa

    2016-09-01

    In the southernmost part of the Parana Basin, records of the late Paleozoic glaciation occur in a discontinuous form preserved in paleovalley systems excavated in the crystalline basement. This paper addresses one of these paleovalleys, the Mariana Pimentel, which extends over 60 km with NW-SE valley direction and a constant width of 2.5 km. With the objective of demonstrating that the paleovalley worked as a fjord during the glaciation period, its origin as well as sedimentary fill and morphology were analyzed. The paleovalley morphology was obtained through electrical resistivity (electrical sounding and lateral mapping) and mathematical modeling in four transverse sections. The morphology of the paleovalley documented by the U-shape, steady width, and high depth reaching up to 400 m are typical features of modern glacial valleys. The sedimentary facies that fill the base of the paleovalley, such as rhythmites and dropstones with thickness up to 70 m and diamictites with faceted pebbles (up to 5 m thick) are signs of its glacial origin. During the glaciation period, the paleovalley had a connection to the epicontinental sea located to the northwest, extended toward Namibia, and was excavated by glaciers from the highlands of this region. Thus, the evidence attests that the Mariana Pimentel paleovalley was a fjord during the late Paleozoic glaciation. The duration of the late Paleozoic glaciation (which is longer than the Quaternary glaciation), the apatite fission track that suggests erosion up to 4 km thick in the study area, and the lack of preserved hanging valleys in the Mariana Pimentel indicate that the paleovalley once featured a higher dimension. Furthermore, the existence of paleofjords excavated in the border of the basement corroborates the idea of small ice centers controlled by topography during the late Paleozoic glaciation.

  18. (210)Pb and compositional data of sediments from Rondonian lakes, Madeira River basin, Brazil.

    Science.gov (United States)

    Bonotto, Daniel Marcos; Vergotti, Marcelo

    2015-05-01

    Gold exploration has been intensive in Brazilian Amazon over the last 40 years, where the use of mercury as an amalgam has caused abnormal Hg concentrations in water bodies. Special attention has been directed to Madeira River due to fact it is a major tributary of Amazon River and that since 1986, gold exploration has been officially permitted along a 350km sector of the river. The (21)(0)Pb method has been used to date sediments taken from nine lakes situated in Madeira River basin, Rondônia State, and to verify where anthropogenic Hg might exist due to gold exploitation in Madeira River. Activity profiles of excess (21)(0)Pb determined in the sediment cores provided a means to evaluate the sedimentation rates using a Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) of unsupported/excess (21)(0)Pb models. A significant relationship was found between the CF:CS sedimentation rates and the mean values of the CRS sedimentation rates (Pearson correlation coefficient r=0.59). Chemical data were also determined in the sediments for identifying possible relationships with Hg occurring in the area. Significant values were found in statistical correlation tests realized among the Hg, major oxides and Total Organic Carbon (TOC) content in the sediments. The TOC increased in the sediment cores accompanied by a loss on ignition (LOI) increment, whereas silica decreased following a specific surface area raising associated to the TOC increase. The CRS model always provided ages within the permitted range of the (21)(0)Pb-method in the studied lakes, whereas the CF:CS model predicted two values above 140 years. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Promoter hypermethylation of CDH1, FHIT, MTAP and PLAGL1 in gastric adenocarcinoma in individuals from Northern Brazil

    Science.gov (United States)

    Leal, Mariana Ferreira; Lima, Eleonidas Moura; Silva, Patrícia Natália Oliveira; Assumpção, Paulo Pimentel; Calcagno, Danielle Queiroz; Payão, Spencer Luiz Marques; Burbano, Rommel Rodríguez; Smith, Marília de Arruda Cardoso

    2007-01-01

    AIM: To evaluate the methylation status of CDH1, FHIT, MTAP and PLAGL1 promoters and the association of these findings with clinico-pathological characteristics. METHODS: Methylation-specific PCR (MSP) assay was performed in 13 nonneoplastic gastric adenocarcinoma, 30 intestinal-type gastric adenocarcinoma and 35 diffuse-type gastric adenocarcinoma samples from individuals in Northern Brazil. Statistical analyses were performed using the chi-square or Fisher's exact test to assess associations between methylation status and clinico-pathological characteristics. RESULTS: Hypermethylation frequencies of CDH1, FHIT, MTAP and PLAGL1 promoter were 98.7%, 53.9%, 23.1% and 29.5%, respectively. Hypermethylation of three or four genes revealed a significant association with diffuse-type gastric cancer compared with nonneoplastic cancer. A higher hypermethylation frequency was significantly associated with H pylori infection in gastric cancers, especially with diffuse-type. Cancer samples without lymph node metastasis showed a higher FHIT hypermethylation frequency. MTAP hypermethylation was associated with H pylori in gastric cancer samples, as well as with diffuse-type compared with intestinal-type. In diffuse-type, MTAP hypermethylation was associated with female gender. CONCLUSION: Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that hypermethylation is associated with gastric carcinogenesis. MTAP promoter hypermethylation can be characterized as a marker of diffuse-type gastric cancer, especially in women and may help in diagnosis, prognosis and therapies. The H pylori infectious agent was present in 44.9% of the samples. This infection may be correlated with the carcinogenic process through the gene promoter hypermethylation, especially the MTAP promoter in diffuse-type. A higher H pylori infection in diffuse-type may be due to greater genetic predisposition. PMID:17552003

  20. Muscoid Diptera as potential vectors of bacterial agents on dairy farms in the northern region of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Josaine Leila Almeida

    2014-12-01

    Full Text Available The aim of this study was to determine the isolation frequency and microbial sensitivity profiles of Escherichia coli, Salmonella spp., and Staphylococcus spp. isolated from synanthropic flies captured in entomological traps placed near the milking parlors of 30 dairy farms located in Northern Paraná, Brazil. In total, 192 flies were captured, and the isolation frequencies of muscids (21/30 = 70% and califorids (27/30 = 90% were significantly higher than that of sarcophagids (7/30 = 23.3%. Bacteriological tests on the internal contents and external surfaces of the flies showed that E. coli was present only in muscids (14.3% and caliphorids (33.3%. Salmonella spp. was isolated from 9.5% of the muscids, 7.4% of the caliphorids, and 14.29% of the sarcophagids. Staphylococcus spp. was isolated from 28.5% of the muscids and 29.6% of the caliphorids. E. coli isolation was more frequent in flies captured on farms at which domestic chickens were housed near the milking parlors (p = 0.031 and which did not use sugarcane for animal feed (p = 0.042. Two out of 27 (7.4% Staphylococcus spp. strains presented a phenotype of coagulase enzyme production. Ceftriaxone, ciprofloxacin, enrofloxacin, and gentamicin were the most effective antibiotics against E. coli and Salmonella spp. Tetracycline was the least effective antibiotic against the isolates. The Staphylococcus spp. strains isolated did not show the phenotype of oxacillin resistance. We conclude that regional flies are potential mechanical vectors of microbial agents able to cause enteritis in goats, mastitis in cows, and contamination of milk products for human consumption.

  1. Timing of deformation and rapid subsidence in the northern Altiplano, Peru: Insights from detrital zircon geochronology of the Ayaviri hinterland basin

    Science.gov (United States)

    Horton, B. K.; Perez, N. D.; Saylor, J. E.

    2011-12-01

    Although age constraints on crustal deformation and sediment accumulation prove critical to testing hypotheses of orogenic plateau construction, a common lack of marine facies, volcanic tuffs, and suitable fossils hinders many attempts at chronological reconstructions. A series of elevated retroarc basins along the axis of the Andean orogenic belt provide opportunities to define the timing of deformation and transformation from foreland to hinterland basin configurations. In this study, we present new U-Pb ages of detrital zircons in the Ayaviri intermontane basin of southern Peru (~4 km elevation) in the northern part of the central Andean (Altiplano) plateau. Nearly all sandstone samples show strong unimodal U-Pb age peaks (generally defined by > 5-50 zircons), suggesting these age peaks represent syndepositional volcanism and can be regarded as accurate estimates of true depositional (stratigraphic) age. Integration of these ages with structural and stratigraphic relationships demonstrate the utility of zircon U-Pb geochronology in defining both (1) the timing of basin partitioning and (2) the pace of sediment accumulation. (1) U-Pb ages for several sandstone samples from growth-strata packages associated with two basin-bounding faults reveal structural partitioning of the Ayaviri basin from late Oligocene to Miocene time. In the north, displacement along the southwest-directed Ayaviri thrust fault commenced in late Oligocene time (~28-24 Ma), inducing initial structural partitioning of an upper Eocene-Oligocene, > 5 km thick succession potentially representing an early Andean retroarc foreland basin. In the south, the Ayaviri basin was further disrupted by initial displacement along the northeast-directed Pasani thrust fault in early to middle Miocene time (~18-15 Ma). (2) Additional U-Pb analyses from the Ayaviri basin fill help delimit the long-term rates of sedimentation, suggesting relatively short-lived (< 5 Myr) pulses of accelerated accumulation. Rapid

  2. Environmental risk assessment in five rivers of Parana River basin, Southern Brazil, through biomarkers in Astyanax spp.

    Science.gov (United States)

    Barros, Ivaldete Tijolin; Ceccon, Juliana Parolin; Glinski, Andressa; Liebel, Samuel; Grötzner, Sonia Regina; Randi, Marco Antonio Ferreira; Benedito, Evanilde; Ortolani-Machado, Claudia Feijó; Filipak Neto, Francisco; de Oliveira Ribeiro, Ciro Alberto

    2017-07-01

    In the current study, water quality of five river sites in Parana River basin (Brazil), utilized for public water supply, was assessed through a set of biomarkers in fish Astyanax spp. Population growth and inadequate use of land are challenges to the preservation of biodiversity and resources such as water. Some physicochemical parameters as well as somatic indexes, gills and liver histopathology, genotoxicity, and biochemical biomarkers were evaluated. The highest gonadosomatic index (GSI) and antioxidant parameters (catalase and glutathione S-transferase activities, non-protein thiols), as well as the lowest damage to biomolecules (lipid peroxidation, protein carbonylation, DNA damage) were observed in site 0 (Piava River), which is located at an environmental protected area. Site 1, located in the same river, but downstream site 0 and outside the protection area, presents some level of impact. Fish from site 2 (Antas River), which lack of riparian forest and suffer from silting, presented the highest micronucleus incidence and no melanomacrophages. Differently, individuals from site 3 (Xambrê River) and site 4 (Pinhalzinho River) which receive surface runoff from Umuarama city, urban and industrial sewage, have the highest incidences of liver and gill histopathological alterations, including neoplasia, which indicated the worst health conditions of all sites. In particular, site 4 had high levels of total nitrogen and ammonia, high turbidity, and very low oxygen levels, which indicate important chemical impact. Comparison of the biomarkers in fish allowed classification of the five sites in terms of environmental impact and revealed that sites 3 and 4 had particular poor water quality.

  3. Ichnology applied to sequence stratigraphic analysis of Siluro-Devonian mud-dominated shelf deposits, Paraná Basin, Brazil

    Science.gov (United States)

    Sedorko, Daniel; Netto, Renata G.; Savrda, Charles E.

    2018-04-01

    Previous studies of the Paraná Supersequence (Furnas and Ponta Grossa formations) of the Paraná Basin in southern Brazil have yielded disparate sequence stratigraphic interpretations. An integrated sedimentological, paleontological, and ichnological model was created to establish a refined sequence stratigraphic framework for this succession, focusing on the Ponta Grossa Formation. Twenty-nine ichnotaxa are recognized in the Ponta Grossa Formation, recurring assemblages of which define five trace fossil suites that represent various expressions of the Skolithos, Glossifungites and Cruziana ichnofacies. Physical sedimentologic characteristics and associated softground ichnofacies provide the basis for recognizing seven facies that reflect a passive relationship to bathymetric gradients from shallow marine (shoreface) to offshore deposition. The vertical distribution of facies provides the basis for dividing the Ponta Grossa Formation into three major (3rd-order) depositional sequences- Siluro-Devonian and Devonian I and II-each containing a record of three to seven higher-order relative sea-level cycles. Major sequence boundaries, commonly coinciding with hiatuses recognized from previously published biostratigraphic data, are locally marked by firmground Glossifungites Ichnofacies associated with submarine erosion. Maximum transgressive horizons are prominently marked by unbioturbated or weakly bioturbated black shales. By integrating observations of the Ponta Grossa Formation with those recently made on the underlying marginal- to shallow-marine Furnas Formation, the entire Paraná Supersequence can be divided into four disconformity-bound sequences: a Lower Silurian (Llandovery-Wenlock) sequence, corresponding to lower and middle units of the Furnas; a Siluro-Devonian sequence (?Pridoli-Early Emsian), and Devonian sequences I (Late Emsian-Late Eifelian) and II (Late Eifelian-Early Givetian). Stratigraphic positions of sequence boundaries generally coincide with

  4. Geochemical studies based in microconstituent elements of oils, betuminous shales and its extracts from Parana Basin, Brazil

    International Nuclear Information System (INIS)

    Clain, Almir Faria

    1997-01-01

    Petroleum contains a high number of elements, considered as microconstituents, once they contribute with less than 1 % of its constitution. The concentration of those elements in the petroleum is very low, because it varies from ng/g to μg/g, therefore the use of sensitive and multielemental techniques is essential for their determination. The objective of this work is to determine the concentration of 46 microconstituent elements in organic extracts from the betuminous shales of the Irati Formation, and correlate oils from Paraná Basin, Brazil, using the instrumental neutron activation analysis and inductively coupled plasma-mass spectrometry (ICP-MS) techniques. Aspects associated with origin, secondary migration, oil age, pH and E h values, and the redox conditions in the depositional environment of the organic matter are discussed. The concentration behavior of the microconstituent elements is presented using statistical techniques of multivariate analysis The determined oil concentration was about 10% and 0.14-0.91% for the reservoir rocks and organic extracts from source rocks, respectively. The concentration values of the elements in oils trended to decrease with the atomic number, ranging from 5-166 μg/g for AI, 24-238 for Fe and 0.0007-0.38 for U. For some elements, which are organically bound to oil, the results were 0.48-39 μg/g to V, 4.4-28 μg/g for Ni and 0.13-27 μg/g for Mo. The concentration values in oils and organic extracts samples presented a statistic distribution almost log-normal for most of determined elements. The concentration ratios U/Th and V/Cr are representative of paleo-redox condition index. (author)

  5. Spatial variability of soil carbon stock in the Urucu river basin, Central Amazon-Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ceddia, Marcos Bacis, E-mail: marcosceddia@gmail.com [Department of Soil, Institute of Agronomy, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropédica, RJ 23890-000 (Brazil); Villela, André Luis Oliveira [Colégio Técnico da UFRRJ, RJ, Seropédica 23890-000 (Brazil); Pinheiro, Érika Flávia Machado [Department of Soil, Institute of Agronomy, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropédica, RJ 23890-000 (Brazil); Wendroth, Ole [Department of Plant & Soil Sciences, University of Kentucky, College of Agriculture, Lexington, KY (United States)

    2015-09-01

    The Amazon Forest plays a major role in C sequestration and release. However, few regional estimates of soil organic carbon (SOC) stock in this ecoregion exist. One of the barriers to improve SOC estimates is the lack of recent soil data at high spatial resolution, which hampers the application of new methods for mapping SOC stock. The aims of this work were: (i) to quantify SOC stock under undisturbed vegetation for the 0–30 and the 0–100 cm under Amazon Forest; (ii) to correlate the SOC stock with soil mapping units and relief attributes and (iii) to evaluate three geostatistical techniques to generate maps of SOC stock (ordinary, isotopic and heterotopic cokriging). The study site is located in the Central region of Amazon State, Brazil. The soil survey covered the study site that has an area of 80 km{sup 2} and resulted in a 1:10,000 soil map. It consisted of 315 field observations (96 complete soil profiles and 219 boreholes). SOC stock was calculated by summing C stocks by horizon, determined as a product of BD, SOC and the horizon thickness. For each one of the 315 soil observations, relief attributes were derived from a topographic map to understand SOC dynamics. The SOC stocks across 30 and 100 cm soil depth were 3.28 and 7.32 kg C m{sup −2}, respectively, which is, 34 and 16%, lower than other studies. The SOC stock is higher in soils developed in relief forms exhibiting well-drained soils, which are covered by Upland Dense Tropical Rainforest. Only SOC stock in the upper 100 cm exhibited spatial dependence allowing the generation of spatial variability maps based on spatial (co)-regionalization. The CTI was inversely correlated with SOC stock and was the only auxiliary variable feasible to be used in cokriging interpolation. The heterotopic cokriging presented the best performance for mapping SOC stock. - Highlights: • The SOC stocks across 30 and 100 cm depth were 3.28 and 7.32 kg C m{sup −2}, respectively. • SOC stocks were 34 and 16

  6. Spatial variability of soil carbon stock in the Urucu river basin, Central Amazon-Brazil

    International Nuclear Information System (INIS)

    Ceddia, Marcos Bacis; Villela, André Luis Oliveira; Pinheiro, Érika Flávia Machado; Wendroth, Ole

    2015-01-01

    The Amazon Forest plays a major role in C sequestration and release. However, few regional estimates of soil organic carbon (SOC) stock in this ecoregion exist. One of the barriers to improve SOC estimates is the lack of recent soil data at high spatial resolution, which hampers the application of new methods for mapping SOC stock. The aims of this work were: (i) to quantify SOC stock under undisturbed vegetation for the 0–30 and the 0–100 cm under Amazon Forest; (ii) to correlate the SOC stock with soil mapping units and relief attributes and (iii) to evaluate three geostatistical techniques to generate maps of SOC stock (ordinary, isotopic and heterotopic cokriging). The study site is located in the Central region of Amazon State, Brazil. The soil survey covered the study site that has an area of 80 km 2 and resulted in a 1:10,000 soil map. It consisted of 315 field observations (96 complete soil profiles and 219 boreholes). SOC stock was calculated by summing C stocks by horizon, determined as a product of BD, SOC and the horizon thickness. For each one of the 315 soil observations, relief attributes were derived from a topographic map to understand SOC dynamics. The SOC stocks across 30 and 100 cm soil depth were 3.28 and 7.32 kg C m −2 , respectively, which is, 34 and 16%, lower than other studies. The SOC stock is higher in soils developed in relief forms exhibiting well-drained soils, which are covered by Upland Dense Tropical Rainforest. Only SOC stock in the upper 100 cm exhibited spatial dependence allowing the generation of spatial variability maps based on spatial (co)-regionalization. The CTI was inversely correlated with SOC stock and was the only auxiliary variable feasible to be used in cokriging interpolation. The heterotopic cokriging presented the best performance for mapping SOC stock. - Highlights: • The SOC stocks across 30 and 100 cm depth were 3.28 and 7.32 kg C m −2 , respectively. • SOC stocks were 34 and 16%, respectively

  7. Fission track analysis and evolution of mesozoic-paleozoic hydrocarbon resource-rocks headed in Northern Jiangsu-South Yellow sea basin

    International Nuclear Information System (INIS)

    Xu Hong; Cai Qianzhong; Sun Heqing; Guo Zhenxuan; Yan Guijing; Dai Jing; Liu Dongying

    2008-01-01

    Fission track data of different geologic epoches from Binhai salient, Yancheng sag, Haian sag, Baiju sag, Gaoyou sag, Hongze sag and Jinhu sag of northern Jiangsu basin and seismic data from Laoshan uplift in South Yellow Sea basin and evolution of Paleozoic hydrocarbon resource-rocks headed in the Northern Jiangsu-South Yellow Sea basin were studied. Results indicate that Binhai salient uplifted in 38-15 Ma, forming 'structure uplifting model', Paleozoic hydrocarbon resource-rocks have the appearance of 'different layers but identical mature, different layers but identical temperature' with Laoshan uplift. All sags have the characters of 'long time heating model', and sedimentations in Cenozoic were exploited by 2 km. Mesozoic-Paleozoic hydrocarbon resource- rocks of Laoshan uplift get ahead of 10 km. Structure evolution was compared with Binhai salient. According to the modeling results of secondary hydrocarbon generation, Mesozoic-Paleozoic hydrocarbon resource-rocks of Laoshan uplift have the good reservoir potentiality and probably become an important new window for sea oil and gas exploration. (authors)

  8. Application of the authigenic 10Be/9Be dating method to Late Miocene-Pliocene sequences in the northern Danube Basin (Pannonian Basin System): Confirmation of heterochronous evolution of sedimentary environments

    Science.gov (United States)

    Šujan, Michal; Braucher, Régis; Kováč, Michal; Bourlès, Didier L.; Rybár, Samuel; Guillou, Valéry; Hudáčková, Natália

    2016-02-01

    Authigenic 10Be/9Be dating method was applied to lacustrine, deltaic and alluvial sequences of the northern Danube Basin (Pannonian Basin System), to bridge the insufficiency of geochronological data for the Late Miocene to Pliocene period. The measurements of 51 samples (both lacustrine and floodplain), ranging from 11.6 to 0.95 Ma are consistent with the existing magnetostratigraphic and biostratigraphic data standing mainly on the evolution degree of endemic mollusk fauna, mammals and dinocysts. This agreement confirms our assumption that the incoming beryllium fluxes remained constant over the studied time period and thus that the two initial 10Be/9Be ratios determined in actual Holocene/Late Pleistocene sediments (lacustrine and floodplain) are valid for these environments. The obtained ages indicate gradual progradation of the deltaic depositional systems across the Danube Basin with a clear time-transgressional character, replacing basin floor and shelfal environments. Deltaic sedimentation occurred firstly in the north at foothills of the Western Carpathians from 11.0 Ma, and changed to the alluvial environment after 10.5 Ma. At the same time (~ 10.5 Ma), the paleo-Danube deltaic system draining the Eastern Alps entered the study area from the Vienna Basin situated on the West. Later, the deltaic systems were merged in the central part of the basin and reached its southeastern margin at ~ 9.4 Ma. Regression of the Lake Pannon from the southernmost part of the study area is evidenced after 8.7 Ma. Alluvial deposition of meandering rivers lasting until 6.0-5.0 Ma followed and was interrupted by the early Pliocene basin inversion. Sedimentation of braided streams took place during the late Pliocene and Pleistocene, reflecting uplift of mountains surrounding the basin margins. This study documents the powerful potential of the authigenic 10Be/9Be dating method and its reliability in a basin with complicated tectonic and sedimentary history. It demonstrates that

  9. A new spiny species of Hypostomus Lacépède (Loricariidae: Hypostominae from thermal waters, upper rio Paraná basin, central Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda O. Martins

    Full Text Available A new species of Hypostomus is described from the rio Quente, rio Paranaíba drainage, in the upper rio Paraná basin in central Brazil. The rio Quente is a peculiar small and shallow fast water stream with water temperatures around 34ºC. The new species is distinguished from all congeners by having the five lateral series of plates with hypertrophied odontodes not aligned in rows and more conspicuous on flanks of caudal peduncle of the larger specimens. The new species is only known from the rio Quente.

  10. A new long-finned Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae from the lower rio Paraná basin, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz F. C. Tencatt

    Full Text Available A new species of Corydoras is described from the lower rio Paraná basin, just downstream from Itaipu Dam, Brazil, close to Paraguay boundary. The new species can be distinguished from most of its congeners by the infraorbital 2 with a posterior laminar expansion conspicuously reduced, first and second dorsal-fin branched rays conspicuously elongated in males, mesethmoid entirely covered by skin, and by the presence of four to six irregular black or brownish blotches on the midline of the flank. The probable occurrence of the new species in the floodplain of the upper portion of the rio Paraná drainage is discussed.

  11. Biological aspects of Schizodon nasutus Kner, 1858 (Characiformes, Anostomidae in the low Sorocaba river basin, São Paulo state, Brazil

    Directory of Open Access Journals (Sweden)

    GA. Villares Junior

    Full Text Available Four biological aspects of Schizodon nasutus in the low Sorocaba river basin, São Paulo, Brazil were analysed. These were accomplished during the year seasons. The fish diet and the feeding activity were investigated by studying the repletion index, which showed no significant differences between seasons. The food items analysed by frequency of occurrence and dominance showed a predominance of vegetable items in the diet. The reproduction, analysed by using the gonadosomatic index, indicated that the reproductive period occurs during the summer period when temperatures are higher and rainfalls are more intense. The amount of accumulated fat and condition factor varied according to reproduction, especially for females.

  12. Two new species of Hyphessobrycon (Teleostei: Characidae from upper rio Tapajós basin on Chapada dos Parecis, central Brazil

    Directory of Open Access Journals (Sweden)

    Tiago Pinto Carvalho

    Full Text Available Two new species of Hyphessobrycon are described from the upper rio Tapajós basin, Mato Grosso, Brazil. Hyphessobrycon melanostichos is distinguished from its congeners by the combination of a conspicuous longitudinal broad black band beginning on the posterior margin of orbit and reaching the tip of middle caudal fin rays, a distinct vertically elongate humeral spot, and 16 to 18 branched anal-fin rays. Hyphessobrycon notidanos is distinguished from its congeners by the combination of an elongate dorsal fin in mature males, a vertically elongate humeral spot, 2-4 maxillary teeth, iii,8 dorsal-fin rays, and 16 to 21 branched anal-fin rays.

  13. A new species of Microglanis(Siluriformes: Pseudopimelodidae from the upper rio Tocantins basin, Goiás State, Central Brazil

    Directory of Open Access Journals (Sweden)

    Oscar Akio Shibatta

    Full Text Available A new species of Microglanis is described from the upper rio Tocantins basin, Barro Alto, Goiás State, Brazil. This species is distinguished from the others by presenting a unique color pattern, consisting of round spots in the flank between the larger dark brown blotches. Moreover, it can be distinguished by the combination of the following features: caudal fin emarginate, the upper lobe slightly larger than the lower, lateral line relatively long, reaching vertical through posterior margin of the pelvic fin, and light stripe on supra-occipital region absent or very narrow and with irregular shape.

  14. Two new species of Hypostomus Lacépède (Teleostei: Loricariidae from the upper rio Paraná basin, Central Brazil

    Directory of Open Access Journals (Sweden)

    Cláudio H. Zawadzki

    Full Text Available Two new species of Hypostomus Lacépède (Teleostei: Loricariidae from the rio Paranaíba and rio Grande basins, both in the upper rio Paraná basin, central Brazil, are described herein. One of them is distinguished from all congeners, except H. albopunctatus, by having the pectoral-fin spine length equal to or smaller than the pelvic-fin spine. From H. albopunctatus, it is distinguished by having round dark spots (vs. pale on body and fins. The second species is distinguished from all congeners, except H. multidens and H. ternetzi, by having more than 115 teeth (vs. less than 109 per ramus on dentary and premaxilla. It is distinguished most readily from H. ternetzi by having teeth with two symmetrical (vs. asymmetrical cusps. It is distinguished from H. multidens by having round dark spots (vs. pale over body and fins.

  15. A giant oil seep at a salt-induced escarpment of the São Paulo Plateau, Espírito Santo Basin, off Brazil: Host rock characteristics and geochemistry

    Science.gov (United States)

    Freire, Antonio Fernando Menezes; Iemini, Juliana Andrade; Viana, Adriano Roessler; Magnavita, Luciano Portugal; Dehler, Nolan Maia; Kowsmann, Renato Oscar; Miller, Dennis James; Bezerra, Sabrina Helena Diniz Gilaberte; Zerfass, Geise de Santana dos Anjos; Shimabukuro, Seirin; Nóbrega, Marcos, II

    2017-12-01

    An international research cruise named Iatá-Piuna took place on the São Paulo Plateau on May 2013 in the Campos and Espírito Santo basins, off Brazil. The cruise was carried ou on board the research vessel (R/V) Yokosuka that hosts the human operated vehicle (HOV) SHINKAI 6500. It aimed at finding chemosynthetic communities, composed of organisms capable of generating their own vital energy by metabolizing organic and inorganic compounds related to seeps. Identification of these organisms could provide information for understanding the origin of life, since they may resemble primitive organisms that existed in the initial stages of life on Earth. During Leg 2 (May 10-24, 2013), however, dives on the northern part of the São Paulo Plateau at the Espírito Santo Basin led to the discovery of a giant oil seep. The seep, ca. 3 nautical miles (ca. 5.6 km) in length is located along an outcrop of Eocene rocks on a salt-induced escarpment of the plateau and at a water depth of ca. 2700 m. The 200 m relief of the seafloor suggests that the seep takes place along an active fault system driven by salt diapirism. The oil was analyzed and identified as a severely biodegraded marine oil, generated by carbonate rocks within a minibasin located to the east of the escarpment. This represents valuable exploratory information because it proves that an active petroleum system is present in the context of minibasins associated with salt diapirism in the area.

  16. Selection of flooded agricultural fields and other landscapes by female northern pintails wintering in Tulare Basin, California

    Science.gov (United States)

    Fleskes, Joseph P.; Jarvis, Robert L.; Gilmer, David S.

    2003-01-01

    Habitat selection and use are measures of relative importance of habitats to wildlife and necessary information for effective wildlife conservation. To measure the relative importance of flooded agricultural fields and other landscapes to northern pintails (Anas acuta) wintering in Tulare Basin (TB), California, we radiotagged female pintails during late August-early October, 1991-1993 in TB and other San Joaquin Valley areas and determined use and selection of these TB landscapes through March each year. Availability of landscape and field types in TB changed within and among years. Pintail use and selection (based upon use-to-availability log ratios) of landscape and field types differed among seasons, years, and diel periods. Fields flooded after harvest and before planting (i.e., pre-irrigated) were the most available, used, and selected landscape type before the hunting season (Prehunt). Safflower was the most available, used, and-except in 1993, when pre-irrigated fallow was available-selected pre-irrigated field type during Prehunt. Pre-irrigated barley-wheat received 19-22% of use before hunting season, but selection varied greatly among years and diel periods. During and after hunting season, managed marsh was the most available, used, and, along with floodwater areas, selected landscape type; pre-irrigated cotton and alfalfa were the least selected field types and accounted for <13% of pintail use. Agricultural drainwater evaporation ponds, sewage treatment ponds, and reservoirs accounted for 42-48% of flooded landscape available but were little used and least selected. Exodus of pintails from TB coincided with drying of pre-irrigated fallow, safflower, and barley-wheat fields early in winter, indicating that preferred habitats were lacking in TB during late winter. Agriculture conservation programs could improve TB for pintails by increasing flooding of fallow and harvested safflower and grain fields. Conservation of remaining wetlands should concentrate

  17. Chemostratigraphy of Late Cretaceous deltaic and marine sedimentary rocks from high northern palaeolatitudes in the Nuussuaq Basin, West Greenland

    DEFF Research Database (Denmark)

    Lenniger, Marc; Pedersen, Gunver Krarup; Bjerrum, Christian J.

    The Nuussuaq Basin in the Baffin Bay area in West Greenland formed as a result of the opening of the Labrador Sea in Late Mesozoic to Early Cenozoic times. The first rifting and the development of the Nuussuaq Basin took place during the Early Cretaceous and was followed by a second rifting phase...

  18. Facies analysis, depositional environments and paleoclimate of the Cretaceous Bima Formation in the Gongola Sub - Basin, Northern Benue Trough, NE Nigeria

    Science.gov (United States)

    Shettima, B.; Abubakar, M. B.; Kuku, A.; Haruna, A. I.

    2018-01-01

    Facies analysis of the Cretaceous Bima Formation in the Gongola Sub -basin of the Northern Benue Trough northeastern Nigeria indicated that the Lower Bima Member is composed of alluvial fan and braided river facies associations. The alluvial fan depositional environment dominantly consists of debris flow facies that commonly occur as matrix supported conglomerate. This facies is locally associated with grain supported conglomerate and mudstone facies, representing sieve channel and mud flow deposits respectively, and these deposits may account for the proximal alluvial fan region of the Lower Bima Member. The distal fan facies were represented by gravel-bed braided river system of probably Scot - type model. This grade into sandy braided river systems with well developed floodplains facies, forming probably at the lowermost portion of the alluvial fan depositional gradient, where it inter-fingers with basinal facies. In the Middle Bima Member, the facies architecture is dominantly suggestive of deep perennial sand-bed braided river system with thickly developed amalgamated trough crossbedded sandstone facies fining to mudstone. Couplets of shallow channels are also locally common, attesting to the varying topography of the basin. The Upper Bima Member is characterized by shallow perennial sand-bed braided river system composed of successive succession of planar and trough crossbedded sandstone facies associations, and shallower channels of the flashy ephemeral sheetflood sand - bed river systems defined by interbedded succession of small scale trough crossbedded sandstone facies and parallel laminated sandstone facies. The overall stacking pattern of the facies succession of the Bima Formation in the Gongola Sub - basin is generally thinning and fining upwards cycles, indicating scarp retreat and deposition in a relatively passive margin setting. Dominance of kaolinite in the clay mineral fraction of the Bima Formation points to predominance of humid sub - tropical

  19. Report on the Predation Index, Predator Control Fisheries, and Program Evaluation for the Columbia River Basin Experimental Northern Pikeminnow Management Program, 2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Russell [Pacific States Marine Fisheries Commission].

    2009-09-10

    This report presents results for year seventeen in the basin-wide Experimental Northern Pikeminnow Management Program to harvest northern pikeminnow1 (Ptychocheilus oregonensis) in the Columbia and Snake Rivers. This program was started in an effort to reduce predation by northern pikeminnow on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern pikeminnow on juvenile salmonids might account for most of the 10-20% mortality juvenile salmonids experience in each of eight Columbia River and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated that, if predator-size northern pikeminnow were exploited at a 10-20% rate, the resulting restructuring of their population could reduce their predation on juvenile salmonids by 50%. To test this hypothesis, we implemented a sport-reward angling fishery and a commercial longline fishery in the John Day Pool in 1990. We also conducted an angling fishery in areas inaccessible to the public at four dams on the mainstem Columbia River and at Ice Harbor Dam on the Snake River. Based on the success of these limited efforts, we implemented three test fisheries on a system-wide scale in 1991 - a tribal longline fishery above Bonneville Dam, a sport-reward fishery, and a dam-angling fishery. Low catch of target fish and high cost of implementation resulted in discontinuation of the tribal longline fishery. However, the sport-reward and dam-angling fisheries were continued in 1992 and 1993. In 1992, we investigated the feasibility of implementing a commercial longline fishery in the Columbia River below Bonneville Dam and found that implementation of this fishery was also infeasible. Estimates of combined annual exploitation rates resulting from the sport-reward and dam-angling fisheries remained at the low end of our target range of 10-20%. This suggested the need for additional

  20. Erosion rates and landscape evolution of the lowlands of the Upper Paraguay river basin (Brazil) from cosmogenic 10Be

    Science.gov (United States)

    Pupim, Fabiano do Nascimento; Bierman, Paul R.; Assine, Mario Luis; Rood, Dylan H.; Silva, Aguinaldo; Merino, Eder Renato

    2015-04-01

    The importance of Earth's low sloping areas in regard to global erosion and sediment fluxes has been widely and vigorously debated. It is a crucial area of research to elucidate geologically meaningful rates of land-surface change and thus the speed of element cycling on Earth. However, there are large portions of Earth where erosion rates have not been well or extensively measured, for example, the tropical lowlands. The Cuiabana lowlands are an extensive low-altitude and low-relief dissected metamorphic terrain situated in the Upper Paraguay river basin, central-west Brazil. Besides exposures of highly variable dissected metamorphic rocks, flat residual lateritic caps related to a Late Cenozoic planation surface dominate interfluves of the Cuiabana lowlands. The timescale over which the lowlands evolved and the planation surface developed, and the rate at which they have been modified by erosion, are poorly known. Here, we present measurements of in situ produced cosmogenic 10Be in outcropping metamorphic bedrock and clastic-lateritic caps to quantify rates of erosion of the surface and associated landforms in order to better understand the Quaternary landscape evolution of these lowlands. Overall, slow erosion rates (mean 10 m/Ma) suggest a stable tectonic environment in these lowlands. Erosion rates vary widely between different lithologies (range 0.57 to 28.3 m/Ma) consistent with differential erosion driving regional landform evolution. The lowest erosion rates are associated with the low-relief area (irregular plains), where clastic-laterite (mean 0.67 m/Ma) and quartzite (mean 2.6 m/Ma) crop out, whereas the highest erosion rates are associated with dissection of residual hills, dominated by metasandstone (mean 11.6 m/Ma) and phyllite (mean 27.6 m/Ma). These data imply that the Cuiabana lowland is comprised of two dominant landform sets with distinct and different dynamics. Because the planation surface (mostly lowlands) is lowering and losing mass more

  1. Structure, Kinematics and Origin of Radial Faults: 3D Seismic Observations from the Santos Basin, offshore Brazil

    Science.gov (United States)

    Coleman, Alexander; Jackson, Christopher A.-L.

    2017-04-01

    Salt stock growth is typically accompanied by the development of geometrically and kinematically complex fault networks in the surrounding country rock. The most common networks comprise radial faults; these are characterised by low displacement (stock into flanking strata. Radial faults are commonly observed in an arched, unpierced roof developed above a rising salt stock; in these cases, the faults are typically well-imaged seismically and likely form due to outer-arc extension during overburden stretching. Radial faults are also found at deeper structural levels, in strata flanking the diapir stem; in these cases, they are typically less well-imaged, thus their structure, kinematics and origin are less well understood. Furthermore, understanding the growth of radial faults may provide insights into hydrocarbon reservoir compartmentalisation and the evolution of neighbouring salt stocks. Here, we use high-quality 3D seismic reflection data from the Santos Basin, offshore Brazil to determine the structure and kinematics, and infer the likely origin of exceptionally well-imaged radial faults overlying and flanking a mature salt stock. Furthermore, we compare the geometric (e.g. throw, geometry, spacing, distribution etc.) and kinematic (e.g. timing of formation and duration of activity) characteristics of radial faults at both structural levels, allowing us to infer their temporal relationship and likely origins. We show that radial faults regardless of their structural level typically have aspect ratios of c. 1.8 - 2, are laterally-restricted in the vicinity of the salt, and have lengths of indices of c. 1, with low throw gradients of 0.05 - 0.1 at the upper tip indicate that radial faults were likely blind. Throws range from 5 - 80 ms, with throw-maxima within 1 - 2 radii of the salt diapir. However, we note that the position of the throw maxima is not at the same level for all radial faults. We propose that radial faults nucleate and initially grow as blind

  2. Depositional setting, petrology and chemistry of Permian coals from the Parana Basin: 2. South Santa Catarina Coalfield, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Kalkreuth, W.; Mexias, A.; Balbinot, M.; Levandowski, J. [Instituto de Geociencias, UFRGS, Porto Alegre (Brazil); Holz, M. [Inst. de Geociencias, UFBA, Salvador, Bahia (Brazil); Willett, J.; Finkelman, R. [U.S. Geological Survey, Reston, VA (United States); Burger, H. [Freie Universitaet Berlin, Geoinformatik, (Germany)

    2010-12-01

    In Brazil economically important coal deposits occur in the southern part of the Parana Basin, where coal seams occur in the Permian Rio Bonito Formation, with major coal development in the states of Rio Grande de Sul and Santa Catarina. The current paper presents results on sequence stratigraphic interpretation of the coal-bearing strata, and petrological and geochemical coal seam characterization from the South Santa Catarina Coalfield, Parana Basin. In terms of sequence stratigraphic interpretation the precursor mires of the Santa Catarina coal seams formed in an estuarine-barrier shoreface depositional environment, with major peat accumulation in a high stand systems tract (Pre-Bonito and Bonito seams), a lowstand systems tract (Ponta Alta seam, seam A, seam B) and a transgressive systems tract (Irapua, Barro Branco and Treviso seams). Seam thicknesses range from 1.70 to 2.39 m, but high proportions of impure coal (coaly shale and shaley coal), carbonaceous shale and partings reduce the net coal thickness significantly. Coal lithoypes are variable, with banded coal predominant in the Barro Branco seam, and banded dull and dull coal predominantly in Bonito and Irapua seams, respectively. Results from petrographic analyses indicate a vitrinite reflectance range from 0.76 to 1.63 %Rrandom (HVB A to LVB coal). Maceral group distribution varies significantly, with the Barro Branco seam having the highest vitrinite content (mean 67.5 vol%), whereas the Irapua seam has the highest inertinite content (33.8 vol%). Liptinite mean values range from 7.8 vol% (Barro Branco seam) to 22.5 vol% (Irapua seam). Results from proximate analyses indicate for the three seams high ash yields (50.2 - 64.2 wt.%). Considering the International Classification of in-Seam Coals, all samples are in fact classified as carbonaceous rocks (> 50 wt.% ash). Sulfur contents range from 3.4 to 7.7 wt.%, of which the major part occurs as pyritic sulfur. Results of X-ray diffraction indicate the

  3. Macroecology, paleoecology, and ecological integrity of terrestrial species and communities of the interior Columbia basin and northern portions of the Klamath and Great Basins.

    Science.gov (United States)

    Bruce G. Marcot; L.K. Croft; J.F. Lehmkuhl; R.H. Naney; C.G. Niwa; W.R. Owen; R.E. Sandquist

    1998-01-01

    This report present information on biogeography and broad-scale ecology (macroecology) of selected fungi, lichens, bryophytes, vascular plants, invertebrates, and vertebrates of the interior Columbia River basin and adjacent areas. Rareplants include many endemics associated with local conditions. Potential plant and invertebrate bioindicators are identified. Species...

  4. Study on the relationships between the structural evolution and sandstone-type uranium mineralization in mesozoic era and cenozoic era in the northern of Chaidam basin

    International Nuclear Information System (INIS)

    Liu Lin; Song Zhe; Song Xiansheng; Feng Wei

    2008-01-01

    By detailed expounding the characteristics of the Mesozoic and Cenozoic structural evolution in northern of Chaidam basin, the author inquires into its relationships with the sandstone-type uranium mineralization, analyzes the prospect of forming uranium deposit, and thinks that the Mesozoic and Cenozoic strata are mainly controlled by the tectonic role of the later Yanshan movement and the later Cenozoic era. The north-west palaeo-structural slope belt is formed in the later Cretacous Epoch that is favorable for developing palaeo-interlayer oxidized zone. After the slightly extensional role of the oldest Tertiary and the early Plioeene, the middle and lower Jurassic were buried, and the block-imbricated slope belts are formed in the tectonic movement of the later Cenozoic, which are favorable for developing recent interlayer oxidized zone. According to drilling, it has the conditions for forming palaeo-recent interlayer oxidized zone sandstone-type uranium deposit at the northern of Chaidam basin. Finally, the author lays his finger on the prospecting of uranium. (authors)

  5. Carboniferous geology and uranium potential of the northeast flank of the Parana Basin and southwest flank of the Parnaiba Basin, Brazil

    International Nuclear Information System (INIS)

    Andrade, S.M. de; Camarco, P.E.N.

    1984-01-01

    The Carboniferous sequences of the northeast flank of the Parana Basin and those of the southwest flank of the Parnaiba Basin have been the subject of discussion and polemics for quite a long time, especially in terms of their stratigraphic relations and depositional environments. Thus, we reinforce our main objective, which is to furnish data for the definition of the uranium potential in these Carboniferous sediments, by adding recently acquired information that should aid in the clarification of the existing controversies. The Carboniferous along the northeast flank of the Parana Basin is represented by the Aquidauana Formation which has been informally divided into three members: lower, middle and upper members. The middle member, of marine origin, constitutes a prospective target for uranium and phosphate associations, in which sandstones interbedded with shales constitute the host rocks. On the other hand, the Carboniferous of the southwest margin of the Parnaiba Basin, which encompasses the Longa, Poti and Piaui Formations has shown very remote possibilities of uranium occurrences. The regional structural framework, as reflected by the Carboniferous rocks along both basin flanks, is characterized by homoclines cut by gravity faults. The faults along these weakness zones were occasionally intruded by basic rocks of Cretaceous age. Superimposed on the regional structure, open folds appear in the form of anticlines and domes. These folds are discontinuous structures resulting from uplift due to vertical stresses or result from differential subsidence along the limbs of the folds. (Author) [pt

  6. Serological evidence for Saint Louis encephalitis virus in free-ranging New World monkeys and horses within the upper Paraná River basin region, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Walfrido Kühl Svoboda

    2014-06-01

    Full Text Available Introduction Saint Louis encephalitis virus (SLEV primarily occurs in the Americas and produces disease predominantly in humans. This study investigated the serological presence of SLEV in nonhuman primates and horses from southern Brazil. Methods From June 2004 to December 2005, sera from 133 monkeys (Alouatta caraya, n=43; Sapajus nigritus, n=64; Sapajus cay, n=26 trap-captured at the Paraná River basin region and 23 blood samples from farm horses were obtained and used for the serological detection of a panel of 19 arboviruses. All samples were analyzed in a hemagglutination inhibition (HI assay; positive monkey samples were confirmed in a mouse neutralization test (MNT. Additionally, all blood samples were inoculated into C6/36 cell culture for viral isolation. Results Positive seroreactivity was only observed for SLEV. A prevalence of SLEV antibodies in sera was detected in Alouatta caraya (11.6%; 5/43, Sapajus nigritus (12.5%; 8/64, and S. cay (30.8%; 8/26 monkeys with the HI assay. Of the monkeys, 2.3% (1/42 of A. caraya, 6.3% 94/64 of S. nigritus, and 15.4% (4/26 of S. cay were positive for SLEV in the MNT. Additionally, SLEV antibodies were detected by HI in 39.1% (9/23 of the horses evaluated in this study. Arboviruses were not isolated from any blood sample. Conclusions These results confirmed the presence of SLEV in nonhuman primates and horses from southern Brazil. These findings most likely represent the first detection of this virus in nonhuman primates beyond the Amazon region. The detection of SLEV in animals within a geographical region distant from the Amazon basin suggests that there may be widespread and undiagnosed dissemination of this disease in Brazil.

  7. Latest Miocene-earliest Pliocene evolution of the ancestral Rio Grande at the Española-San Luis Basin boundary, northern New Mexico

    Science.gov (United States)

    Daniel J. Koning,; Aby, Scott B.; Grauch, V. J.; Matthew J. Zimmerer,

    2016-01-01

    We use stratigraphic relations, paleoflow data, and 40Ar/39Ar dating to interpret net aggradation, punctuated by at least two minor incisional events, along part of the upper ancestral Rio Grande fluvial system between 5.5 and 4.5 Ma (in northern New Mexico). The studied fluvial deposits, which we informally call the Sandlin unit of the Santa Fe Group, overlie a structural high between the San Luis and Española Basins. The Sandlin unit was deposited by two merging, west- to southwest-flowing, ancestral Rio Grande tributaries respectively sourced in the central Taos Mountains and southern Taos Mountains-northeastern Picuris Mountains. The river confluence progressively shifted southwestward (downstream) with time, and the integrated river (ancestral Rio Grande) flowed southwards into the Española Basin to merge with the ancestral Rio Chama. Just prior to the end of the Miocene, this fluvial system was incised in the southern part of the study area (resulting in an approximately 4–7 km wide paleovalley), and had sufficient competency to transport cobbles and boulders. Sometime between emplacement of two basalt flows dated at 5.54± 0.38 Ma and 4.82±0.20 Ma (groundmass 40Ar/39Ar ages), this fluvial system deposited 10–12 m of sandier sediment (lower Sandlin subunit) preserved in the northern part of this paleovalley. The fluvial system widened between 4.82±0.20 and 4.50±0.07 Ma, depositing coarse sand and fine gravel up to 14 km north of the present-day Rio Grande. This 10–25 m-thick sediment package (upper Sandlin unit) buried earlier south- to southeast-trending paleovalleys (500–800 m wide) inferred from aeromagnetic data. Two brief incisional events are recognized. The first was caused by the 4.82±0.20 Ma basalt flow impounding south-flowing paleodrainages, and the second occurred shortly after emplacement of a 4.69±0.09 Ma basalt flow in the northern study area. Drivers responsible for Sandlin unit aggradation may include climate

  8. Actual Evapotranspiration in the Al-Khazir Gomal Basin (Northern Iraq Using the Surface Energy Balance Algorithm for Land (SEBAL and Water Balance

    Directory of Open Access Journals (Sweden)

    Hussein Jassas

    2015-04-01

    Full Text Available Increasing dependence on groundwater requires a detailed determination of the different outputs and inputs of a basin for better water management. Determination of spatial and temporal actual evapotranspiration (ETa, in this regard, is of vital importance as there is significant water loss from drainage basins. This research paper uses the Surface Energy Balance Algorithm for Land (SEBAL, as well as the water balance, to estimate the spatial and temporal ETa in the Al-Khazir Gomal Basin, Northern Iraq. To compensate for the shortage in rainfall, and to irrigate summer crops, farmers in this basin have been depending, to a large extent, on groundwater extracted from the underlying unconfined aquifer, which is considered the major source for both domestic and agricultural uses in this basin. Rainfed farming of wheat and barley is one of the most important activities in the basin in the winter season, while in the summer season, agricultural activity is limited to small rice fields and narrow strips of vegetable cultivation along the Al-Khazir River. The Landsat Thematic Mapper images (TM5 acquired on 21 November 2006, 9 March 2007, 5 May 2007, 21 July 2007, and 23 September 2007 were used, along with a digital elevation model (DEM and ground-based meteorological data, measured within the area of interest. Estimation of seasonal ETa from periods between satellite overpasses was computed using the evaporative fraction (Ʌ. The water balance approach was utilized, using meteorological data and river hydrograph analysis, to estimate the ETa as the only missing input in the predefined water balance equation. The results of the two applied methods were comparable. SEBAL results were compared with the land use land cover (LULC map. The river showed the highest ETa, as evaporation from the free-water surface. Rice fields, irrigated in the summer season, have a high ETa in the images, as these fields are immersed in water during June, July and August

  9. Modeling pollution potential input from the drainage basin into Barra Bonita reservoir, São Paulo – Brazil

    Directory of Open Access Journals (Sweden)

    RB. Prado

    Full Text Available In this study multi-criteria modeling tools are applied to map the spatial distribution of drainage basin potential to pollute Barra Bonita Reservoir, São Paulo State, Brasil. Barra Bonita Reservoir Basin had undergone intense land use/land cover changes in the last decades, including the fast conversion from pasture into sugarcane. In this respect, this study answers to the lack of information about the variables (criteria which affect the pollution potential of the drainage basin by building a Geographic Information System which provides their spatial distribution at sub-basin level. The GIS was fed by several data (geomorphology, pedology, geology, drainage network and rainfall provided by public agencies. Landsat satellite images provided land use/land cover map for 2002. Ratings and weights of each criterion defined by specialists supported the modeling process. The results showed a wide variability in the pollution potential of different sub-basins according to the application of different criterion. If only land use is analyzed, for instance, less than 50% of the basin is classified as highly threatening to water quality and include sub basins located near the reservoir, indicating the importance of protection areas at the margins. Despite the subjectivity involved in the weighing processes, the multi-criteria analysis model allowed the simulation of scenarios which support rational land use polices at sub-basin level regarding the protection of water resources.

  10. The transtensional offshore portion of the northern San Andreas fault: Fault zone geometry, late Pleistocene to Holocene sediment deposition, shallow deformation patterns, and asymmetric basin growth

    Science.gov (United States)

    Beeson, Jeffrey W.; Johnson, Samuel Y.; Goldfinger, Chris

    2017-01-01

    We mapped an ~120 km offshore portion of the northern San Andreas fault (SAF) between Point Arena and Point Delgada using closely spaced seismic reflection profiles (1605 km), high-resolution multibeam bathymetry (~1600 km2), and marine magnetic data. This new data set documents SAF location and continuity, associated tectonic geomorphology, shallow stratigraphy, and deformation. Variable deformation patterns in the generally narrow (∼1 km wide) fault zone are largely associated with fault trend and with transtensional and transpressional fault bends.We divide this unique transtensional portion of the offshore SAF into six sections along and adjacent to the SAF based on fault trend, deformation styles, seismic stratigraphy, and seafloor bathymetry. In the southern region of the study area, the SAF includes a 10-km-long zone characterized by two active parallel fault strands. Slip transfer and long-term straightening of the fault trace in this zone are likely leading to transfer of a slice of the Pacific plate to the North American plate. The SAF in the northern region of the survey area passes through two sharp fault bends (∼9°, right stepping, and ∼8°, left stepping), resulting in both an asymmetric lazy Z–shape sedimentary basin (Noyo basin) and an uplifted rocky shoal (Tolo Bank). Seismic stratigraphic sequences and unconformities within the Noyo basin correlate with the previous 4 major Quaternary sea-level lowstands and record basin tilting of ∼0.6°/100 k.y. Migration of the basin depocenter indicates a lateral slip rate on the SAF of 10–19 mm/yr for the past 350 k.y.Data collected west of the SAF on the south flank of Cape Mendocino are inconsistent with the presence of an offshore fault strand that connects the SAF with the Mendocino Triple Junction. Instead, we suggest that the SAF previously mapped onshore at Point Delgada continues onshore northward and transitions to the King Range thrust.

  11. Gravimetric survey and modeling of the basement morphology in the sedimentary thickness characterization, NE portion of Paraná Sedimentary Basin - Brazil

    Directory of Open Access Journals (Sweden)

    Maximilian Fries

    2017-05-01

    Full Text Available ABSTRACT: The northeast portion of the Paraná Sedimentary Basin is distinguished by structural highs as the known Pitanga Dome, an uplifted structure identified in the last century. It represents a geological and evolutionary evidence of the Paraná Sedimentary Basin and has undergone inspired studies and intense exploration surveys. This study consists of a gravimetric survey in the Pitanga Dome area, State of São Paulo, Brazil. The Bouguer gravity anomalies have been identified and related to the structural high, sedimentary thickness, and the basement morphology. Processing and enhancement techniques were used for forward modeling based on previous studies. The three models from profiles sectioning the dome have a sedimentary thickness varying from 200 to 1.250 meters. The adopted methodology has provided important results determining that the Pitanga Dome can be understood through rational 3D visualization. The area can be interpreted as an undulating basement with thinning of sedimentary rocks related to deep features (structures in the crust/mantle limit (Moho uplift. This characteristic is confirmed by the sedimentary layer thickening present throughout the surrounding area. The results also offer important insights and support for further studies concerning the genesis and evolution of this and other uplifted structures of the Paraná Sedimentary Basin.

  12. Evaluation of mercury levels in sediment and soil samples from Vila Nova river basin, in Amapa State, Brazil, using radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Goncalves, C.; Favaro, D.I.T.; Vasconcellos, M.B.A.; Guimaraes, J.R.D.; Forti, M.C.

    2000-01-01

    Results from a survey on mercury concentration in sediments and soils from a gold mining area along the Vila Nova river, in Amapa State, Brazil, are presented. These values were compared with those from the Igarape Pedra Preta basin, an area unaffected by mining activities. Total mercury contents were determined in the muddy (silt+clay) fraction of the sediments and in the -1 for soils and 14 μg x kg -1 for sediments when 200 mg of sample were analysed. The Hg results obtained from a comparison between our current method (RNAA) and CV AAS are also presented. Mercury levels showed to be very high in the soils and sediments collected in the Vila Nova river (up to 2 mg x kg -1 ) when compared to background values (0.3 mg x kg -1 ) for this region. An enrichment factor was calculated, using Al as a normalizing factor. It showed values up to 8 in sediments of the Vila Nova river basin, indicating a relatively high degree of pollution as compared to the values of about 1 for the samples of the Igarape Pedra Preta basin. (author)

  13. Management of water use in the Paraíba River, PB, Brazil basin based on water grants and charge models

    Directory of Open Access Journals (Sweden)

    Márcia Araújo de Almeida

    2016-11-01

    Full Text Available One of the challenges in the management of water resources is to advance water distribution mechanisms to allow them to balance the basin's available water with the demands of its various economic sectors. This research evaluated the combined use of a model of grant optimization with a proposed model of charging for the use of raw water in order to assist decision makers in the distribution of water of the Acauã Reservoir, located in the basin of the Paraiba River in the State of Paraiba, Brazil. The grant model allowed optimizing the achievement of the demand requests according to water use priorities defined in four scenarios, balancing demand and availability. It was shown that it can be used in decision-making processes in the evaluation of new grant requests in basins controlled by reservoirs. The proposed charging model incorporated various profiles of water users using various coefficients which enabled the definition of the amount to be charged to encourage the rational use of water, not just a tax collection mechanism.

  14. Diagnostic of ribeirão Mestre d’Armas sub-basin using two methods of rapid environmental assessment, Federal District, Central Brazil

    Directory of Open Access Journals (Sweden)

    Julio Cesar Joveli

    2010-04-01

    Full Text Available Rapid environmental assessments have been used to describe the quality and semi-quantitative attributes of the ecosystems along an environmental gradient using visual observations and few measurements. The aim of this study was to identify and measure anthropogenic impacts on ribeirão Mestre d’Armas sub-basin, Federal District, Central Brazil, and to propose its environmental zoning. This study was performed using two methods based on rapid environmental assessment: a rapid river assessment protocol, to evaluate in an integrated form the features of a lotic system section according to the conservation or degradation condition of the fluvial environment; and the Leopold matrix, to identify and evaluate the anthropogenic impacts. The environmental zoning of this sub-basin detected three areas: preserved, transition and urban areas. The environmental assessment revealed, the preserved area had lotic stretches with natural features under low magnitude of impacts, except on burned areas. In the transition area, there was a predominance of lotic stretches with altered features, due to agriculture and livestock activities of intermediate level of impacts. Finally, the urban area had altered and impacted lotic stretches of higher magnitude due to anthropogenic impacts. Thus, this study revealed large differences among the areas detected by environmental zoning, according to the methods used. These methods were considered complementary in relation to environmental diagnostic of the ribeirão Mestre d’Armas sub-basin.

  15. The Comparison of Detrital Zircon Ages to Point Count Provenance Analysis for the Pottsville Sandstone in the Northern Appalachian Foreland Basin Venango County, Pennsylvania

    Science.gov (United States)

    Loveday, S.; Harris, D. B.; Schiappa, T.; Pecha, M.

    2017-12-01

    The specific sources of sediments deposited in the Appalachian basin prior to and immediately following the Alleghenian orogeny has long been a topic of debate. Recent advances in U-Pb dating of detrital zircons have greatly helped to determine some of the sources of these sediments. For this study, sandstone samples were collected from the Pottsville Formation in the northern Appalachian Foreland Basin, Venango County, Pennsylvania to provide supplementary data for previous work that sought to describe the provenance of the same sediments by point counts of thin sections of the same units. Results of this previous work established that the provenance for these units was transitional recycled orogenic, including multiple recycled sediments, and that a cratonic contribution was not able to be determined clearly. The previous results suggested that the paleoenvironment was a fluvial dominated delta prograding in the northern direction. However, no geochronologic data was found during this study to confirm this interpretation. We sought to verify these results by U-Pb analysis of detrital zircons. Samples were collected from the areas where the previous research took place. U-Pb ages were found from sample at the highest elevation and lowest elevation. In the first sample, sample 17SL01 (younger sample stratigraphically), the zircons yield U-Pb age range peaks at 442-468 ma and 1037-1081 ma. The probability density plot for this specific sample displays a complete age gap from 500 ma to 811 ma. In the second sample, sample 17SL03 (older rock stratigraphically), the zircons yield U-Pb ages range peaks of 424-616 ma and 975-1057 ma. This sample doesn't show any ages younger than 424 ma and it doesn't display the sample age gap as sample 17SL01 does. The ages of zircons are consistent with thin section point counting provenance results from previous research suggesting zircon transport from the northern direction.

  16. Eocene to Miocene back-arc basin basalts and associated island arc tholeiites from northern Sulawesi (Indonesia): Implications for the geodynamic evolution of the Celebes basin

    International Nuclear Information System (INIS)

    Rangin, C.; Maury, R.C.; Bellon, H.; Cotten, J.; Polve, M.; Priadi, B.; Soeria-Atmadja, R.; Joron, J.L.

    1997-01-01

    Eocene BABB basalts intruded by tholeiitic and calk-alkalic island arc magmatic rocks are reported from the north arm of Sulawesi (Indonesia). Age and geochemical similarities between these basalts and those drilled in the Celebes Sea indicate this North Sulawesi volcanic arc was built on the same oceanic crust. The 25 deg late Neogene clockwise rotation of the north arm of Sulawesi following its collision with fragments of Australia (Sula, Buton) is not sufficient to explain the asymmetrical magnetic anomalies in the Celebes basin. The North Sulawesi island arc could be interpreted as having progressively retreated northward on its own Celebes sea back arc basin, during an episode of Palaeogene-early Neogene tectonic erosion along the trench. (authors)

  17. Heavy mineral as a tool to refine the stratigraphy of kaolin deposits in the Rio Capim Area, Northern Brazil

    Directory of Open Access Journals (Sweden)

    Ana M. Góes

    2007-09-01

    Full Text Available Studies of heavy minerals in kaolin deposits from the Ipixuna Formation in the Rio Capim area (Northern Brazil showed a mature to super mature assemblage dominated by zircon and tourmaline, and subordinately rutile, kyanite and staurolite. These minerals do not change much throughout the whole section; however, each kaolin unit displays a particular signature, defined by differences in the proportions of the whole assemblage of heavy minerals, as well as of their textural characteristics. This work revealed that the lower and upper kaolin units can be definitely considered as distinct depositional sequences. A higher proportion of opaque minerals and higher zircon values characterize the lower unit. The higher volumes of anhedric, rounded to sub-rounded grains of zircon and tourmaline in the upper unit suggests that this includes grains that were undergone to a higher degree of reworking. The increased volume of unaltered staurolite and kyanite in the upper unit leads to conclude that, even considering sediment reworking, a distinct source must be invoked. The results also show that the characteristics of the heavy mineral assemblage from the intermediate unit are comparable with those from the upper unit, which suggests they might record a same stratigraphic sequence.Estudos de minerais pesados provenientes em depósitos cauliníticos da Formação Ipixuna na região do rio Capim (Brasil revelaram uma mineralogia matura a supermatura, representada dominantemente por zircão e turmalina e, subordinadamente, rutilo, cianita e estaurolita. Os minerais encontrados não variam muito, entretanto cada unidade caulinítica apresenta uma assinatura particular definida por diferenças nasproporções entre os principais minerais, assim como em suas características texturais. Este trabalho demonstrou que asunidades de caulim soft (inferior e semi-flint (superior podem ser consideradas seqüências deposicionais distintas. As altas percentagens de opacos

  18. Long-Term Ground-Water Levels and Transmissivity in the Blackstone River Basin, Northern Rhode Island

    Science.gov (United States)

    Eggleston, Jack R.; Church, Peter E.; Barbaro, Jeffrey R.

    2007-01-01

    Ground water provides about 7.7 million gallons per day, or 28 percent of total water use in the Rhode Island part of the Blackstone River Basin. Primary aquifers in the basin are stratified glacial deposits, composed mostly of sand and gravel along valley bottoms. The ground-water and surface-water system in the Blackstone River Basin is under stress due to population growth, out-of-basin water transfers, industrialization, and changing land-use patterns. Streamflow periodically drops below the Aquatic Base Flow standard, and ground-water withdrawals add to stress on aquatic habitat during low-flow periods. Existing hydrogeologic data were reviewed to examine historical water-level trends and to generate contour maps of water-table altitudes and transmissivity of the sand and gravel aquifer in the Blackstone River Basin in Rhode Island. On the basis of data from four long-term observation wells, water levels appear to have risen slightly in the study area during the past 55 years. Analysis of available data indicates that increased rainfall during the same period is a likely contributor to the water-level rise. Spatial patterns of transmissivity are shown over larger areas and have been refined on the basis of more detailed data coverage as compared to previous mapping studies.

  19. Geochronological and sedimentological evidences of Panyangshan foreland basin for tectonic control on the Late Paleozoic plate marginal orogenic belt along the northern margin of the North China Craton

    Science.gov (United States)

    Li, Jialiang; Zhou, Zhiguang; He, Yingfu; Wang, Guosheng; Wu, Chen; Liu, Changfeng; Yao, Guang; Xu, Wentao; Zhao, Xiaoqi; Dai, Pengfei

    2017-08-01

    There is a wide support that the Inner Mongolia Palaeo-uplift on the northern margin of the North China Craton has undergone an uplifting history. However, when and how did the uplift occurred keeps controversial. Extensive field-based structural, metamorphic, geochemical, geochronological and geophysical investigations on the Inner Mongolia Palaeo-uplift, which suggested that the Inner Mongolia Palaeo-uplift was an uplifted region since the Early Precambrian or range from Late Carboniferous-Early Jurassic. The geochemical characteristics of the Late Paleozoic to Early Mesozoic intrusive rocks indicated that the Inner Mongolia Palaeo-uplift was an Andean-type continental margin that is the extensional tectonic setting. To address the spatial and temporal development of the Inner Mongolia Palaeo-uplift, we have carried out provenance analysis of Permian sedimentary rocks which collected from the Panyangshan basin along the northern margin of the North China Craton. The QFL diagram revealed a dissected arc-recycled orogenic tectonic setting. Moreover, the framework grains are abundant with feldspar (36-50%), indicating the short transport distance and unstable tectonic setting. Detrital zircon U-Pb analysis ascertained possible provenance information: the Precambrian basement ( 2490 and 1840 Ma) and continental arc magmatic action ( 279 and 295 Ma) along the northern margin of the North China Craton. The projection in rose diagrams of the mean palaeocurrent direction, revealing the SSW and SSE palaeoflow direction, also shows the provenance of the Panyangshan basin sources mainly from the Inner Mongolia Palaeo-uplift. The andesite overlying the Naobaogou Formation has yielded U-Pb age of 277.3 ± 1.4 Ma. The additional dioritic porphyry dike intruded the Naobaogou and Laowopu Formations, which has an emplacement age of 236 ± 1 Ma. The above data identify that the basin formed ranges from Early Permian to Middle Triassic (277-236 Ma). Accordingly, the Inner Mongolia

  20. Mapping of the 18S and 5S ribosomal RNA genes in Astyanax altiparanae Garutti & Britski, 2000 (Teleostei, Characidae from the upper Paraná river basin, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Fernandes

    2006-01-01

    Full Text Available Fluorescence in situ hybridization (FISH was undertaken in order to determinate the chromosomal distribution pattern of 18S and 5S ribosomal DNAs (rDNA in four populations of the characid fish Astyanax altiparanae from the upper Paraná river basin, Brazil. The 18S rDNA probe FISH revealed numerical and positional variations among specimens from the Keçaba stream compared to specimens of the other populations studied. In contrast to the variable 18S rDNA distribution pattern, highly stable chromosomal positioning of the 5S rDNA sites was observed in the four A. altiparanae populations. Divergence in the distribution pattern of 18S and 5S rDNA sites is also discussed.

  1. A new species of Hypostomus Lacépède, 1803 (Siluriformes: Loricariidae from the rio Tocantins-Araguaia basin, Brazil

    Directory of Open Access Journals (Sweden)

    Cláudio Henrique Zawadzki

    Full Text Available Hypostomus delimaiis described from the rio Tocantins, Tocantins State, and from the rio Araguaia, Pará, and Tocantins States, Brazil. The new species is distinguished from all other Hypostomusspecies, except from H. carinatus, H. hoplonites, and H. watwata, by the presence of five to eight (mode seven predorsal plates limiting posterior border of the supraoccipital bone (vs. one to three plates. It can be distinguished from H. carinatus, H. hoplonites, and H. watwata by having pale spots over darker background on body and fins (vs. dark spots over lighter background. The species was only found in the middle stretches of the rio Tocantins-Araguaia basin. The first collection of specimens assigned to the new species was done in the rio Tocantins before the construction of the Tucuruí dam. Recently additional material was collected in the rio Araguaia, in a habitat that soon will be flooded for the construction of the Santa Isabel hydroelectric power station.

  2. SEROLOGICAL DETECTION OF HEPATITIS A VIRUS IN FREE-RANGING NEOTROPICAL PRIMATES (Sapajus spp., Alouatta caraya) FROM THE PARANÁ RIVER BASIN, BRAZIL.

    Science.gov (United States)

    Svoboda, Walfrido Kühl; Soares, Manoel do Carmo Pereira; Alves, Max Moreira; Rocha, Tatiana Carneiro; Gomes, Eliane Carneiro; Menoncin, Fabiana; Batista, Paulo Mira; Silva, Lineu Roberto da; Headley, Selwyn Arlington; Hilst, Carmen Lúcia Scortecci; Aguiar, Lucas M; Ludwig, Gabriela; Passos, Fernando de Camargo; Souza, Júlio Cesar de; Navarro, Italmar Teodorico

    2016-01-01

    Nonhuman primates are considered as the natural hosts of Hepatitis A virus (HAV), as well as other pathogens, and can serve as natural sentinels to investigate epizootics and endemic diseases that are of public health importance. During this study, blood samples were collected from 112 Neotropical primates (NTPs) (Sapajus nigritus and S. cay, n = 75; Alouatta caraya, n = 37) trap-captured at the Paraná River basin, Brazil, located between the States of Paraná and Mato Grosso do Sul. Anti-HAV IgG antibodies were detected in 4.5% (5/112) of NTPs, specifically in 6.7% (5/75) of Sapajus spp. and 0% (0/37) of A. caraya. In addition, all samples were negative for the presence of IgM anti-HAV antibodies. These results suggest that free-ranging NTPs were exposed to HAV within the geographical regions evaluated.

  3. Petrographic, mineralogical, geochemical and paleo environmental characterization of radioactive anomaly associated to carbonate rocks from Jandaira formation of high cretaceous from Potiguar basin - Rio Grande do Norte - Brazil

    International Nuclear Information System (INIS)

    Matsuda, N.S.

    1988-01-01

    The Jandaira Formation (Turonian/Maastrichtian - Potiguar Basin, Brazil) presents an anomalous radioactive marker in the upper part of its carbonatic section. This marker of 3-20 m in thickness, comprises an area of about 3500 Km 2 and shows a radioactivity of 470 UAPI, against a background of 20 UAPI on the Gamma Ray Log. In the effort of characterizing this marker, petrological, mineralogical, geological and paleontological, analyses were made in ditch samples of selected 23 wells. This marker is composed by bioclastics packstones to mudstones, mainly constituted of planktonic and bentonic forams, deposited in relatively deep water. Chemical analysis of the P 205 richest samples, the ones show that they are also enriched on U, F, As, Cr, Cu, Mo, Ni, Pb, S, Se, V, Y, Yb and on all rare-earth elements. The origin of the radioactive anomaly is due to the presence of sedimentary phosphates (phosphorite) made-up of uraniferous coloform apatite. (author)

  4. Study of weathering velocity of rocks with uranium as a natural tracer. Application to two drainage basins of the north-east of Brazil

    International Nuclear Information System (INIS)

    Costa Pinto Moreira Nordemann, L.M. da.

    1977-01-01

    Study on rock weathering rate, i.e. rock-soil interface formation, by measuring the elements dissolved in river waters. These elements are used as natural tracers. This work has been carried out in the drainage basin of Preto and Salgado Rivers, in