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Sample records for alfonso basin gulf

  1. Changes in productivity and redox conditions during the Last Glacial Maximum as recorded in high-resolution geochemical records from Alfonso Basin, Gulf of California

    Science.gov (United States)

    Choumiline, K.; Lyons, T. W.; Carriquiry, J. D.; Perez-Cruz, L. L.; Beaufort, L.

    2015-12-01

    The Last Glacial Maximum represents the most recent major sea level low stand in Earth history. Such changes in eustatic sea level impacted the oxygenation of marine basins, yet the characteristics and mechanisms of those impacts remain poorly known. Specific basin conditions are needed to develop, record, and preserve those paleoredox changes through time most effectively, including rapid sedimentation rates and silled basin morphologies. The anoxic Alfonso Basin, partially separated from the Gulf of California by a bathymetric sill, is such a place. The basin is located in a dry semiarid region dominated by dust inputs and only occasional tropical cyclone-induced fluvial contributions. We present the first multi-proxy reconstruction of southern Gulf of California paleoredox that covers an uninterrupted timespan from the Late Pleistocene to the present, with an emphasis on the Last Glacial Maximum. In this research we contrast geochemical data from a 47-meter-long sediment core (collected with the giant CALYPSO corer aboard the R/V Marion Dufresne) with the solid phase and pore water chemical data from a shorter but very detailed box core (collected on the R/V El Puma), both from Alfonso Basin. Our results show that during the Late Pleistocene and throughout the Holocene several paleoredox shifts occurred, often accompanied by differences in lamination (laminated/massive alternations) and trace element (Mo, V, U) compositions; detailed Fe chemistry (FeHR/FeTand Fe/Al ratios); as well as carbon and sulfur concentrations and isotope ratios. For example, FeHR/FeT ratios indicate values of roughly 0.15 during the Last Glacial Maximum (lower than theoretic threshold of 0.2 between oxic and anoxic), suggesting more oxic conditions, in comparison to 0.25 and higher in the Holocene. Most of the variability seen in these proxies is related to global sea level change, while some variability is instead related to local variations in paleoproductivity, often connected to

  2. Associations of major and trace components in time-series settling particle samples from Cuenca Alfonso, SW Gulf of California

    Science.gov (United States)

    Rodríguez-Castañeda, A. P.; Shumilin, E.; Silverberg, N.; Morton-Bermea, O.; Hernandez-Alvarez, E.; Aguirre-Bahena, F.

    2007-12-01

    Cuenca Alfonso is a natural sedimentation basin in Bahía de La Paz, southern Baja California Peninsula, an arid subtropical region characterized by limited land runoff with a productive surface layer overlying a well-developed Oxygen Minimum Zone. A time-series sediment trap program was initiated in 2002 to help understand the processes controlling variations in the biogeochemistry of this environment. INAA, ICP-MS and ICP-OES analyses, as well as flame AAS were made for major and trace elements in 105 subsamples of material collected at 350 m depth during 2002-2005. Principal component analysis, including data for organic and inorganic carbon, biogenic silica and the lithogenic fraction, yielded four factors. Factor 1 (25% of the total variance) showed high eigenvalues for the classical terrigenous aluminosilicate elements: Al, Fe, Mn Sc. High loadings also occurred for the group of light to medium REEs (except for Eu). The latter are frequently associated with acid source rocks, such the granites and rhyolitic volcanics exposed on the margin of the bay. Factor 2 (18%) grouped mainly REEs, with high loading on the heavier members of the series that are more typical of basic rocks (thick sequences of andesitic volcanics occur to the NW), as well as Ni and Rb. Factor 3 (12%) appears to represent carbonate organism production, with high loadings for Cinorg, Ca and moderate levels for Corg and Cu, while %litho is moderately negative, as is biogenic silica. The fourth factor (9%) is characterized by high negative loadings for Cd, Co, Se and moderately negative values for Corg. Moderate positive loadings occur only for Sr and, at lower levels, for U, Sb and %lithogenic. This suggests that this grouping is related to particles that have been partially transformed within the Oxygen Minimum Zone. The results will be examined for distinctive periods within the time-series, such as the hurricane-influenced months of August-September 2003, the generally very low fluxes

  3. Gulf Coast Basins and Uplifts [gcstructsg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide generalized outlines of major basins and uplifts in the Gulf Coast region modified after Plate 2, Principal structural features, Gulf of Mexico...

  4. Cretaceous Onlap, Gulf of Mexico Basin [cretonlapg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The maximum extent of Cretaceous onlap is generalized from Plate 3, Structure at the base and subcrop below Mesozoic marine section, Gulf of Mexico Basin (compiled...

  5. Particulate Matter Fluxes in Cuenca Alfonso During 2002-2005

    Science.gov (United States)

    Silverberg, N.; Aguirre-Bahena, F.

    2007-05-01

    Time-series sediment trap data were collected between 2002 and 2005 from Cuenca Alfonso, a 400m-deep basin in Bahía de La Paz, a large embayment on the southwestern coast of the Gulf of California. Despite the lack of significant land drainage in this semi-dessert environment, terrigenous material, probably wind-born, dominates the sinking particulate matter. Peak lithogenic fluxes appear to be associated with higher frequencies of wind gusts stronger than 5 ms-1. Total mass flux fluctuated from week to week, and between years, averaging 277 gm-2y-1, essentially the same as radiometrically-determined accumulation rates of about 0.4 mmy-1 in cores of the underlying sediment. In 2003, the passage of 2 hurricanes induced high winds and flash flooding and the total mass flux offshore remained very high for two weeks following each event. This unusual sedimentation was equivalent to that of a full year without hurricanes and such events may account for some of the laminations found in cores. During most of 2005, on the other hand, sedimentation rates were lower than average. Although fluxes of all components tended to be highest during late fall and early winter, biogenic fluxes displayed peaks during all seasons of the year in Cuenca Alfonso. This is in contrast to the strong seasonal alternation between terrigenous sedimentation and diatom blooms observed in Guaymas Basin in the central Gulf. Furthermore, calcium carbonate dominated over biogenic silica within the marine component. Average annual fluxes of CaCO3, biogenic silica and POC were 52.5, 32.5 and 13.9 gm-2y-1, respectively.

  6. Temporal variations of C, N, δ13C, and δ15N in organic matter collected by a sediment trap at Cuenca Alfonso, Bahía de La Paz, SW Gulf of California

    Science.gov (United States)

    Aguiñiga, Sergio; Sanchez, Alberto; Silverberg, Norman

    2010-09-01

    To monitor the composition and the vertical flux of particulate matter from the sea surface, a sediment trap was moored in Cuenca Alfonso, Bahía de La Paz, a zone of high productivity in the southwestern Gulf of California. Carbonate-free samples from 2002 to 2005 were analyzed for C org, N, δ13C, and δ15N. The results show seasonal and interannual variability, with the δ13C and δ15N values larger in spring and summer than in fall and winter. The C:N ratio and δ13C increased by 1.5 units from 2002 to 2003-2005, suggesting a change in the supply of organic matter and-or the use or preferential degradation of N org. There was no interannual variation in δ15N. The occasional high δ15N values suggest that physical mechanisms, such as the shoaling and advection into the bay of 15N-rich subsurface equatorial water, occur over short time periods. The latter is presumed to be related to the periodic development of a significant cyclonic gyre in the southern Gulf.

  7. Orogenic Thrust Belt, Gulf of Mexico Basin [gcthrustbg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide the general location of the Ouachita and Appalachian structural fronts slightly modified from Plate 4, Natural resources, Gulf of Mexico Basin...

  8. Seismic stratigraphic framework of deep central Gulf of Mexico basin

    Energy Technology Data Exchange (ETDEWEB)

    Shaub, F.J.; Buffler, R.T.; Parsons, J.G.

    1984-11-01

    The deep Gulf of Mexico basin is underlain by up to 10 km (33,000 ft) of Jurassic(.) to Holocene layered sedimentary rocks. The multichannel reflection seismic record from the deep Gulf of Mexico was divided into six seismic stratigraphic units for study of the geologic history of this accumulation. The basal Challenger unit (Jurassic (.) to middle Cretaceous) is considered coeval with early basin formation. We interpret it as a deep marine sequence overlying oceanic crust in the central basin and as continental and shallow through deep marine rocks, including thick evaporites, over adjacent transitional crust. The next three units, Campeche, Lower Mexican Ridges and Upper Mexican Ridges, indicate that from the Late Cretaceous through middle Miocene the basin filled progressively from the west and north, most probably with siliceous turbidites interlayered with pelagic deposits. By the late Tertiary, however, salt and shale deformation within thick sedimentary sections along the western and northern margins trapped much of the incoming sediment supply on the shelves and upper slopes. The late Miocene to Pliocene Cinco de Mayo unit, therefore, represents a relatively starved interval. In contrast, the uppermost, or Sigsbee unit, includes the Mississippi Fan, an accumulation up to 3 km (10,000 ft) thick of mainly mass-transported deposits that bypassed the shelf and slope and were deposited directly onto the abyssal plain. In the western and southwestern portions of the deep basin, beyond the fan pinchout, the Pleistocene section is largely a continuation of the Pliocene suspension deposits.

  9. 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.

  10. Geothermal and Hydrocarbon Regimes, Northern Gulf of Mexico Basin

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Paul H.

    1975-01-01

    Geothermal heat flow in the Gulf basin is primarily a function of its hydrology. Water expelled from sediments with deepening burial and increasing overburden load escapes upward and toward the basin margin. Where it moves freely in the hydropressure zone, the basin is relatively cool; but where rapid sedimentation and contemporaneous faulting have retarded water loss from compacting sediments, the interstitial fluid pressure reflects a part of the overburden load, and the formation waters are superheated and geopressured. The geopressured zone is common below depths of about 3 km (9,600 ft) in the basin, beneath an area of 375,000 km{sup 2} (150,000 mi{sup 2}), and extends downward perhaps 15 km (50,000 ft) to the base of Cenozoic deposits. The upper boundary of the geopressured zone is the most important physical interface in the basin. Across it the head of formation water increases downward from a few hundred to several thousand feet above sea level; the geothermal gradient increases downward from 20° to 40° C/km to 100°C/km or more; the salinity of formation water decreases downward, commonly by 50,000 mg/l or more; and the porosity of shale and sand increases downward by 10 to 25 percent. Petroleum matures in geopressured clay at 140° to 220°F. Montmorillonite is dehydrated at 180° to 250°F; fresh water released may equal half the volume of the mineral altered. Molecular solubility in fresh water of the hydrocarbons in Gulf basin crude, under geopressured zone conditions, could account for petroleum resources of the basin. Exsolution of petroleum hydrocarbons near the geopressured zone boundary could account for observed occurrences. This geopressured zone is a natural pressure vessel from which superheated water of moderate salinity could be produced through wells, each yielding millions of gallons a day at pressures of several thousand pounds per square inch, and temperatures above 300°F. with considerable amounts of methane gas in solution. (63

  11. Messinian Events: View from the Provence Basin (Gulf of Lion,Western Mediterranean)

    OpenAIRE

    Bache, François; Gorini, C.; Olivet, Jean-Louis; Rabineau, Marina; Aslanian, Daniel; Suc, J.p.

    2009-01-01

    Though the late Miocene "Messinian Salinity Crisis" has been intensely researched along the circum- Mediterranean basins, few studies have focused on the central part of the Mediterranean Basin and, especially, the pre-salt deposits. Within the Western Mediterranean, the Gulf of Lion is exceptional in that its sedimentary strata have not been significantly deformed. In addition, the Gulf of Lion is characterized by a relatively constant subsidence with continuous accommodation space for sedim...

  12. Comparison of Kuqa foreland basin with Persian Gulf Basin in salt tectonics

    Institute of Scientific and Technical Information of China (English)

    Guimei WAN; Liangjie TANG; Wenzheng JIN

    2007-01-01

    Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective.

  13. Plate interactions control middle late Miocene, proto-Gulf and Basin and Range extension in the southern Basin and Range

    Science.gov (United States)

    Henry, Christopher D.; Aranda-Gomez, J. Jorge

    2000-03-01

    Middle-late Miocene (proto-Gulf; ˜12-6 Ma) extension around the Gulf of California (Gulf Extensional Province) is commonly interpreted as resulting from partitioning of oblique Pacific-North American plate motion into strike-slip displacement along the margin and east-northeast extension perpendicular to the margin within the North American plate. We propose that this mechanism also applies to kinematically similar, predominantly east-northeast extension that occurred at the same time throughout the southern Basin and Range province, from southern Arizona and New Mexico to the Trans-Mexican Volcanic Belt. New field and 40Ar/ 39Ar data in Sinaloa and Durango confirm that this episode of extension occurred on the mainland side of the Gulf and in the Basin and Range east of the Sierra Madre Occidental, which is generally considered the eastern margin of the Gulf Extensional Province. Published data indicate the middle-late Miocene episode also occurred across the northern and southern ends of the Sierra Madre where the Gulf Extensional Province connects with the Basin and Range: (1) from central Sonora into southern Arizona and New Mexico, and (2) from Nayarit into central Mexico north of the Trans-Mexican Volcanic Belt. This episode appears to have affected an area that continues to the eastern edge of the Basin and Range province in Texas and San Luis Potosi. Recognition that this episode of extension affected the entire southern Basin and Range resolves the discrepancy between the amount of extension calculated based on plate reconstructions and that based on field data within the Gulf Extensional Province alone. Published plate reconstructions require 160 to 110 km of east-northeast extension between ˜12 and 6 Ma. If taken up solely within the Gulf Extensional Province, this would have generated 66 to 78% extension, which is much greater than observed. Spread across the entire southern Basin and Range it requires only ˜20% total extension, which is more

  14. Post Mid-Cretaceous seismic stratigraphy and geologic history, deep Gulf of Mexico basin

    Energy Technology Data Exchange (ETDEWEB)

    Feng Jianhua; Buffler, R.T. (Univ. of Texas, Austin (United States))

    1991-03-01

    The deep Gulf of Mexico basin is underlain by up to 10 km of sedimentary rocks. This section is subdivided into two megasequences separated by a prominent, basinwide, mid-Cretaceous sequence boundary (MCSB), which marks a major turning point in the history of the Gulf basin. The post-MCSB section consists of the more distal portions of large siliciclastic wedges that partially fill the basin. A detailed seismic stratigraphic analysis has subdivided the post-MCSB, pre-Pleistocene section into 12 new sequences, which have been mapped throughout the entire deep basin using UTIG and all available industry seismic data. Correlation with two published Exxon seismic lines on the northeastern shelf provides tentative age control for the five youngest sequences. The correlation across the slope was made using a dense grid of UTIG and industry seismic data with minimum interference from salt structures. These ages were further confirmed by correlation with DSDP sites 90 and 91 in the western Gulf. This study suggests that the base of the Mississippi Fan is Upper miocene in age, which is older than the Plio-Pleistocene age proposed by previous studies. Isopach maps of each new sequence document the progressive filling of the deep basin and the shift of major deep water depocenters from the west and northwest to the north. This corresponds to the shift of the deltaic depocenters along the northern Gulf margin. A tentative correlation of the deep Gulf sequences with the major northern Gulf coast depositional episodes is proposed.

  15. Potential for deep basin-centered gas accumulation in Travis Peak (Hosston) Formation, Gulf Coastal Basin

    Science.gov (United States)

    Bartberger, Charles E.; Dyman, Thaddeus S.; Condon, Steven M.

    2003-01-01

    The potential of Lower Cretaceous sandstones of the Travis Peak Formation in the northern Gulf Coast Basin to harbor a basin-centered gas accumulation was evaluated by examining (1) the depositional and diagenetic history and reservoir properties of Travis Peak sandstones, (2) the presence and quality of source rocks for generating gas, (3) the burial and thermal history of source rocks and time of gas generation and migration relative to tectonic development of Travis Peak traps, (4) gas and water recoveries from drill-stem and formation tests, (5) the distribution of abnormal pressures based on shut-in-pressure data, and (6) the presence or absence of gas-water contacts associated with gas accumulations in Travis Peak sandstones. The Travis Peak Formation (and correlative Hosston Formation) is a basinward-thickening wedge of terrigenous clastic sedimentary rocks that underlies the northern Gulf Coast Basin from eastern Texas across northern Louisiana to southern Mississippi. Clastic infl ux was focused in two main fl uvial-deltaic depocenters?one located in northeastern Texas and the other in southeastern Mississippi and northeastern Louisiana. Across the main hydrocarbon-productive trend in eastern Texas and northern Louisiana, the Travis Peak Formation is about 2,000 ft thick. Most Travis Peak hydrocarbon production in eastern Texas comes from drilling depths between 6,000 and 10,000 ft. Signifi cant decrease in porosity and permeability occurs through that depth interval. Above 8,000-ft drilling depth in eastern Texas, Travis Peak sandstone matrix permeabilities often are signifi cantly higher than the 0.1-millidarcy (mD) cutoff that characterizes tight-gas reservoirs. Below 8,000 ft, matrix permeability of Travis Peak sandstones is low because of pervasive quartz cementation, but abundant natural fractures impart signifi cant fracture permeability. Although pressure data within the middle and lower Travis Peak Formation are limited in eastern Texas

  16. Length-weight relationships of Garra rufa, in the Tigris and Persian Gulf basins of Iran

    Directory of Open Access Journals (Sweden)

    Iraj Hashemzadeh

    2015-01-01

    Full Text Available Garra rufa, a bottom dwelling freshwater fish and native to the Middle East, is distributed in the southwestern of Iran and the Tigris basin. Considering the importance of length-weight relationships data of a species in different habitats, the length-weight relationship of G. rufa from 13 rivers in the Persian Gulf and the Tigris basins was explored. The value of exponent b ranged from 2.74 to 3.19 with average of 2.99 in the Tigris basin and 2.96 in the Persian Gulf basin which was in normal range (2.5-3.5. As the length-weight parameters were concluded for each location separately, this information would be useful for further population dynamics researches.

  17. 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.

  18. Morphology and Late Quaternary sedimentation in the Gulf of Oman Basin

    Science.gov (United States)

    Uchupi, Elazar; Swift, S. A.; Ross, D. A.

    The morphology of the Gulf of Oman Basin, a 3,400 m deep oceanic basin between Oman and southern Pakistan and southern Iran, ranges from a convergent margin (Makran margin) along the north side, a passive type (Oman margin) along the south side, translation types along the basin's west (Zendan Fault-Oman Line) and east (Murray Ridge) sides and a narrow continental rise and a wide abyssal plain in the centre of the basin. Sediment input into the basin during the Late Quaternary has been mainly from the north as a result of the uplift of the Coast Makran Mountains in the Late Miocene-Pliocene. Today most of this detritrus is deposited on the shelf and upper continental slope and perched basins behind the fold/fault ridges on the lower slope. The presence of fans and channels on the continental rise on the north side of the basin indicate, however, that continental derived debris was, and possibly is, being transported to the deep-sea by turbidity currents via gaps in the ridges on the lower slope. In addition to land derived terrigenous sediments, the basin deposits also contain biogenic (organic matter and calcium carbonate), eolian detritus and hydrates and authigenic carbonates from the tectonic dewatering of the Makran accretionary wedge. The eolian sediment is carried into the Gulf of Oman Basin from Arabia and the Mesopotamia Valley by the northwesterly Shamal winds. This type of detritus was particularly abundant during the glacial arid periods 21,000-20,000 and 11,000 (Younger Dryas) years ago when exposure of the Persian (Arabian) Gulf increased the area of dust entrainment and shifted the position of the source of the eolian sediments closer to the basin.

  19. Seismic stratigraphy of middle Cretaceous unconformity (MCU) in central Gulf of Mexico basin

    Energy Technology Data Exchange (ETDEWEB)

    Faust, M.J.

    1986-05-01

    A widespread high-amplitude reflector seen on seismic data throughout the Gulf of Mexico has been called the middle Cretaceous unconformity (MCU). This reflector seems to be a major stratigraphic boundary in the Gulf of Mexico basin. It is believed to correspond to Vail's type 1 unconformity of middle Cenomanian age (97 Ma), which records an eustatic drop in sea level of approximately 200 m. This study area includes the entire Gulf of Mexico, except areas of thick, highly deformed salt where following the MCU with any degree of confidence becomes impossible. The MCU is easy to follow in multichannel seismic reflection profiles collected by the Institute for Geophysics of the University of Texas at Austin in the Gulf of Mexico. In central, deeper part of the gulf, reflectors above and below the MCU are parallel. In the southern and eastern rims of the gulf, along the Campeche and Florida escarpments, reflectors are truncated below the MCU and show onlap relationships above it. Therefore, the MCU may be interpreted as representing an unconformity along the southern and eastern rims of the Gulf of Mexico basin. The unconformity appears to die out and grade into a conformable section toward the center of the basin, and channeling is common along the Campeche and Florida escarpments. These channels can be projected back into canyons in the escarpments, which were probably initiated by subaerial exposure of the top of the escarpments during the middle Cretaceous lowstand. The downslope channels, being sourced by the canyons, were cut in deep water.

  20. Geophysical observations on northern part of Georges Bank and adjacent basins of Gulf of Maine

    Science.gov (United States)

    Oldale, R.N.; Hathaway, J.C.; Dillon, William P.; Hendricks, J.D.; Robb, James M.

    1974-01-01

    Continuous-seismic-reflection and magnetic-intensity profiles provide data for inferences about the geology of the northern part of Georges Bank and the basins of the Gulf of Maine adjacent to the bank. Basement is inferred to be mostly sedimentary and volcanic rocks of Paleozoic age that were metamorphosed and intruded locally by felsic and mafic plutons near the end of the Paleozoic Era. During Late Triassic time, large fault basins formed within the Gulf of Maine and probably beneath Georges Bank. The fault basins and a possible major northeast-trending fault zone beneath the northern part of the bank probably formed as a result of the opening Atlantic during the Mesozoic. Nonmarine sediments, associated with mafic flows and intrusive rocks, were deposited in the fault basins as they formed. The upper surface of the Triassic and pre-Triassic rocks that comprise basement is an unconformity that makes up much of the bottom of the Gulf of Maine. Depth to the basement surface beneath the gulf differ greatly because of fluvial erosion in Tertiary time and glacial erosion in Pleistocene time. Beneath the northern part of Georges Bank the basement surface is smoother and slopes southward. Prominent valleys, cut before Late Cretaceous time, are present beneath this part of the bank. Cretaceous, Tertiary, and possibly Jurassic times were characterized by episodes of coastal-plain deposition and fluvial erosion. During this time a very thick wedge of sediment, mostly of Jurassic(?) and Cretaceous ages, was deposited on the shelf. Major periods of erosion took place at the close of the Cretaceous and during the Pliocene. Fluvial erosion during the Pliocene removed much of the coastal-plain sedimentary wedge and formed the Gulf of Maine. Pleistocene glaciers eroded all but a few remnants of the coastal-plain sediments within the gulf and deposited a thick section of drift against the north slope of Georges Bank and a thin veneer of outwash on the bank. Marine sediments were

  1. La conquista de Niebla por Alfonso X

    OpenAIRE

    García Sanjuán, Alejandro

    2000-01-01

    La conquista de Niebla en 660 H/1262 d.n.e. por el rey Alfonso X (1252-1284) puso fin a los cinco siglos y medio de Historia andalusí de dicha ciudad, largo período iniciado desde su sumisión por `Abd al- c Aziz b. Milsá en 94/713, al comienzo de la irrupción islámica en la Península Ibérica. Se trata, por lo tanto, de un episodio de gran relevancia en el devenir histórico de esta localidad, que ya desde época visigoda fue el principal núcleo urbano del territorio onubens...

  2. Alfonso Reyes y el cine del porvenir

    OpenAIRE

    Betina Keizman

    2015-01-01

    Este artículo se propone situar la reflexión de Alfonso Reyes sobre el cine en el marco de las recepciones del primer cine, considerando también cómo esta reflexión se articula en relación con el pensamiento crítico del escritor mexicano. En particular, se analiza el modo en que, por vía de la especulación, Reyes ensaya posibles redefiniciones para una nueva distribución de lo sensible y de las artes, de los valores cognitivos y expresivos de la luz y de los vínculos arte-ciencia. Lo que se l...

  3. Alfonso Reyes y el cine del porvenir

    Directory of Open Access Journals (Sweden)

    Betina Keizman

    2015-07-01

    Full Text Available Este artículo se propone situar la reflexión de Alfonso Reyes sobre el cine en el marco de las recepciones del primer cine, considerando también cómo esta reflexión se articula en relación con el pensamiento crítico del escritor mexicano. En particular, se analiza el modo en que, por vía de la especulación, Reyes ensaya posibles redefiniciones para una nueva distribución de lo sensible y de las artes, de los valores cognitivos y expresivos de la luz y de los vínculos arte-ciencia. Lo que se lee en Reyes es un esfuerzo por pensar nuevas formas de inventiva que se desprenden (o podrían desprenderse del arte cinematográfico.

  4. Coccolithophore export production in Guaymas Basin, Gulf of California: response to climate forcing

    Science.gov (United States)

    Ziveri, P.; Thunell, R. C.

    The flux and taxonomic composition of coccolithophores has been determined for sediment trap samples collected over a two-year period from Guaymas Basin, central Gulf of California. The Gulf of California is a subtropical marginal sea with exceptionally high rates of primary productivity. The annual biogenic sediment fluxes are largely dominated by silica, with diatoms as the major contributor to the opal flux. For the July 1990 through November 1992 study period, the total coccolithophore export production in Guaymas varied in response to the strength of El Niño/Southern Oscillation (ENSO). Coccolithophore production follows the general surface primary productivity pattern with relatively high fluxes from late fall to late winter, and low production in the summer when the water column is highly stratified and nutrient depleted. High fluxes of up to 10 9 coccoliths m -2 day-1 and 3×10 6 coccospheres m -2 day-1 indicate that coccolithophores are an important component of the phytoplankton population in Guaymas Basin. The intensification of ENSO conditions during 1992 altered the typical hydrography of the Gulf of California by increasing SST and reducing the strength of spring upwelling. This is reflected in reduced opal and diatom fluxes during this period. Conversely, these more oligotrophic conditions resulted in higher total coccolithophore fluxes during spring and summer 1992. Gephyrocapsa oceanica is present in the Gulf throughout the study period, but is dominant during weak or non-ENSO times. Emiliania huxleyi and, to a lesser degree, Florisphaera profunda are abundant during strong ENSO periods. Two major coccolithophore signals are indicative of strong ENSO conditions and could be used as paleo-ENSO indicators in the Gulf of California: (a) the switch in dominance between G. oceanica and E. huxleyi and (b) high abundances of the deep dwelling species F. profunda. The abundance of this latter species shows a strong inverse relationship with opal fluxes. A

  5. Stratigraphical links between Miocene Alpine Foreland basin and Gulf of Lion Passive Margin during lowstands

    Science.gov (United States)

    Rubino, Jean-Loup; Gorini, Christian; Leroux, Estelle; Aslanian, Daniel; Rabineau, Marina; Parize, Olivier; Besson, David

    2015-04-01

    Miocene peri-alpine foreland basin is connected toward the south with the Gulf of Lion passive margin and is predominantly filled by marine shallow water molassic deposits ranging from lower Miocene to Pliocene in age. Nine to ten depositional sequences are recorded and partly preserved in this basin and can be traced into the post rift part of the Gulf of Lion. One of the most surprising feature of the stratigraphic infill is the total lack of lowstand deposits within the foreland basin ; All superimposed sequences only includes transgressive and highstand System Tracts separated by erosional sequence boundaries and the development of incised valley networks filled by tidal deposits during transgression; Besson et al. 2005. It means that the entire foreland basin in SE France is exposed during lowstand periods without any preservation of fluvial deposits. By place few forced regression wedges are preserved at the transition between the foreland and the passive margin, close to the present day coastline. To date no real lowstand wedges have never been reported in the offshore of the Gulf of Lion. A reinterpretation of the best old vintage 2D dip seismic profiles along the passive margin validates the idea that the foreland basin is entirely exposed as well as the proximal part of the passive margin; first because some incised valleys can be occasionally picked on the shelf and second mainly because well defined superimposed or juxtaposed prograding lowstand wedges with nicely defined clinoforms onlapping the sequence boundaries can be recognized on the distal part of the shelf from the Burdigalian to the Messinian. Their ages being constrains by the Calmar well calibration. Unfortunately, they can't be continuously mapped all along the shelf break because of the strong erosion related to the Messinian Unconformity and the associated huge sea level fall.So we have to explain why during the lowstands, exceptionally long fluvial valley networks (more than 300km) can

  6. Paleoclimatic and Paleoceanographic Holocene Sedimentary Records in the Gulf of California - Eastern Pacific Ocean Interhemispheric Connections

    Science.gov (United States)

    Perez-Cruz, L.; Urrutia-Fucugauchi, J.

    2009-05-01

    Initial results of a study on the distribution, thickness and stratigraphy of the sedimentary sequences in the Gulf of California are presented. The Gulf is an elongated narrow young oceanic basin bordered by the Baja California peninsula and mainland Mexico. The Gulf extends over 1200 km across the Tropic of Cancer from the tropical to the temperate zones, surrounded by arid and semi-arid regions, including the Sonora-Mojave Desert. Paleoceanographic conditions are dominated by water exchange at the Gulf mouth and water masses changes along the Gulf. Tectonic basins reach down in excess of 3000 m depths and get shallower to the north. Here we focus on the Holocene sediment sequences in the southern sector, which contains several marginal and central anoxic basins that constitute rich archives of paleoclimatic and paleoenvironmental evolution for the past 3.6 Ma. In the mouth area, main sources of sediments are silicic volcanic and intrusive rocks in the Baja peninsula and mainland, including Los Cabos and Puerto Vallarta batholiths. Fine-grained eolian dusts, pluvial and biogenic sediments are present in the sediment cores in the Gulf basins such as La Paz, Alfonso, Carmen, Pescadero and Guaymas basins. Turbiditic currents and tephra deposits also occur in the cores. Paleoclimatic records show the influences of regional processes, including the ENSO and PDO signals marked by drought and increased precipitation phases. Relative distribution and thickness of sediments at the mouth of the Gulf correlate with bathymetry and location with respect to spreading center, transform faults and margins of the peninsula and mainland Mexico. Rock magnetic core scans and mineralogy at few locations are available, which allow inferences on sediment sources, transport and deposition processes, diagenesis, paleoceanographic and paleoclimatic evolution for the Holocene.

  7. Seismic Structural Setting of Western Farallon Basin, Southern Gulf of California, Mexico.

    Science.gov (United States)

    Pinero-Lajas, D.; Gonzalez-Fernandez, A.; Lopez-Martinez, M.; Lonsdale, P.

    2007-05-01

    Data from a number of high resolution 2D multichannel seismic (MCS) lines were used to investigate the structure and stratigraphy of the western Farallon basin in the southern Gulf of California. A Generator-Injector air gun provided a clean seismic source shooting each 12 s at a velocity of 6 kts. Each signal was recorded during 6- 8 s, at a sampling interval of 1 ms, by a 600 m long digital streamer with 48 channels and a spacing of 12.5 m. The MCS system was installed aboard CICESE's (Centro de Investigacion Cientifica y de Educacion Superior de Ensenada) 28 m research vessel Francisco de Ulloa. MCS data were conventionally processed, to obtain post- stack time-migrated seismic sections. The MCS seismic sections show a very detailed image of the sub-bottom structure up to 2-3 s two-way travel time (aprox. 2 km). We present detailed images of faulting based on the high resolution and quality of these data. Our results show distributed faulting with many active and inactive faults. Our study also constrains the depth to basement near the southern Baja California eastern coast. The acoustic basement appears as a continuous feature in the western part of the study area and can be correlated with some granite outcrops located in the southern Gulf of California islands. To the East, near the center of the Farallon basin, the acoustic basement changes, it is more discontinuous, and the seismic sections show a number of diffracted waves.

  8. Regional maps of subsurface geopressure gradients of the onshore and offshore Gulf of Mexico basin

    Science.gov (United States)

    Burke, Lauri A.; Kinney, Scott A.; Dubiel, Russell F.; Pitman, Janet K.

    2013-01-01

    The U.S. Geological Survey created a comprehensive geopressure-gradient model of the regional pressure system spanning the onshore and offshore Gulf of Mexico basin, USA. This model was used to generate ten maps that included (1) five contour maps characterizing the depth to the surface defined by the first occurrence of isopressure gradients ranging from 0.60 psi/ft to 1.00 psi/ft, in 0.10-psi/ft increments; and (2) five supporting maps illustrating the spatial density of the data used to construct the contour maps. These contour maps of isopressure-gradients at various increments enable the identification and quantification of the occurrence, magnitude, location, and depth of the subsurface pressure system, which allows for the broad characterization of regions exhibiting overpressured, underpressured, and normally pressured strata. Identification of overpressured regions is critical for exploration and evaluation of potential undiscovered hydrocarbon accumulations based on petroleum-generation pressure signatures and pressure-retention properties of reservoir seals. Characterization of normally pressured regions is essential for field development decisions such as determining the dominant production drive mechanisms, evaluating well placement and drainage patterns, and deciding on well stimulation methods such as hydraulic fracturing. Identification of underpressured regions is essential for evaluating the feasibility of geological sequestration and long-term containment of fluids such as supercritical carbon dioxide for alternative disposal methods of greenhouse gases. This study is the first, quantitative investigation of the regional pressure systems of one of the most important petroleum provinces in the United States. Although this methodology was developed for pressure studies in the Gulf of Mexico basin, it is applicable to any basin worldwide.

  9. Depositional setting of the Jurassic Haynesville seismic sequence in the Apalachicola Basin, northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, L.M.; Buffler, R.T. (Univ. of Texas, Austin (USA))

    1990-05-01

    Seismic and well data from the northeastern Gulf of Mexico were used to define the seismic stratigraphy, geologic history, and depositional setting of the Jurassic (Kimmeridgian) Haynesville sequence in the Apalachicola basin. The data show that Haynesville clastic sedimentation updip was coeval with Haynesville carbonate deposition downdip. The regional Jurassic seismic stratigraphic framework includes, in ascending order, the Louann Salt Norphlet-Smackover, Haynesville, and Cotton Valley sequences. In the vicinity of Destin dome, wells have penetrated Haynesville sandstones, shales, and anhydrites. These clastics correlate with low amplitude, low-continuity reflections that characterize the Haynesville over a broad area updip. Similar reflections within the overlying (Tithonian-earliest Berriasian) Cotton Valley clastic sequence make seismic definition of the top Haynesville sequence boundary difficult updip. As Haynesville clastics are replaced by carbonates downdip, a high amplitude reflection marks the top of the sequence. Haynesville carbonates conformably overlie (Oxfordian) Smackover carbonates in the basin center, and the lower sequence boundary cannot be defined where disrupted by growth faults associated with early movement of the (Callovian ) Louann Salt. Sigmoid clinoforms document Haynesville shelf margin development Seismic facies also include oblique clinoforms that prograde eastward into the basin from the Southern Platform and Middle Ground Arch. No wells penetrate this facies. Mapping of the seismic facies and correlation with well data suggest a depositional setting for the Haynesville sequence in which influx of terrigenous clastics probably derived from adjacent land areas to the north and northeast filled a broad lagoon behind a carbonate shelf margin.

  10. Active Atlantic Basin Hurricane Forecast Adds to Concerns About Gulf Oil Spill

    Science.gov (United States)

    Showstack, Randy

    2010-06-01

    During the 6-month Atlantic Basin hurricane season that began on 1 June, there could be between 14 and 23 named storms with top winds of at least 39 miles per hour (mph) in the Gulf of Mexico and Caribbean Sea, according to a forecast issued in late May by the Climate Prediction Center of the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service. The forecast indicates that the named storms could include eight to 14 hurricanes with top winds of at least 74 mph and three to seven major hurricanes with top winds of at least 111 mph. In comparison, the seasonal average is 11 named storms, six hurricanes, and two major hurricanes. The busiest hurricane season on record was 2005, with 28 named storms, including hurricanes Katrina and Rita.

  11. Bathymetric characterization of tectonically active basins in the northern Gulf of California

    Science.gov (United States)

    Prol-Ledesma, R. M.; Canet, C.; Dando, P. R.

    2009-04-01

    The Wagner Basin can be considered a "nascent spreading centre" that evolved from a half graben with a thick sediment cover that may mask magmatic activity at depth. The 200-210 m deep Wagner and Consag Basins are the northernmost of the 8 active extensional basins within the Gulf of California rift system and have been assumed to be mostly hydrothermally inactive; however, bathymetric data show dense deep faulting, mainly on the SE edge of the basins; additionally, the presence of extensive gas venting and heated sediments along the Wagner Fault was observed. Detailed bathymetry of the Wagner and Consag Basins shows the steep eastern edge of the basins bordered by the Wagner Fault. Bathymetry and profiler data revealed large vertical displacements due to faulting that disrupted the sedimentary column. More than 246 bubble plumes were mapped on the echo-sounder profiles, many rising to the surface from 65 -150 m depth and the area affected by low bottom pH, due to CO2 discharge, was in excess of 365 km2. Bubbles were observed breaking the sea surface from some large plumes. Only a minority of the vents present were mapped with the echo-sounders, since the closest survey lines were 1km apart. Based on the bottom coverage of the acoustic beam we estimate that there are at least 15,000 individual gas vents along the Wagner fault. Profiler images showed gas channels and chimneys associated with sedimentary layers. The gas plumes originated from sites of intense disruptions of the upper sediments (synsedimentary faults, pockmarks, mud domes and diapirs and raised irregular hard reflectors). Beneath the plumes, there were enhanced sedimentary reflectors and acoustic blanking indicative of subsurface gas accumulation. One of the strongest vents was associated with a mud diapir. Cemented sediments were common inside pockmarks and around gas outlets; 13 (22%) of grab and box core samples in the outgassing area contained these but in many cases the grab was empty after

  12. Radiogenic heat production in sedimentary rocks of the Gulf of Mexico Basin, south Texas

    Science.gov (United States)

    McKenna, T.E.; Sharp, J.M.

    1998-01-01

    Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we calculate radiogenic heat production for Stuart City (Lower Cretaceous) limestones, Wilcox (Eocene) sandstones and mudrocks, and Frio (Oligocene) sandstones and mudrocks from south Texas. Heat production rates range from a low of 0.07 ?? 0.01 ??W/m3 in clean Stuart City limestones to 2.21 ?? 0.24??W/m3 in Frio mudrocks. Mean heat production rates for Wilcox sandstones, Frio sandstones, Wilcox mudrocks, and Frio mudrocks are 0.88, 1.19, 1.50, and 1.72 ??W/m3, respectively. In general, the mudrocks produce about 30-40% more heat than stratigraphically equivalent sandstones. Frio rocks produce about 15% more heat than Wilcox rocks per unit volume of clastic rock (sandstone/mudrock). A one-dimensional heat-conduction model indicates that this radiogenic heat source has a significant effect on subsurface temperatures. If a thermal model were calibrated to observed temperatures by optimizing basal heat-flow density and ignoring sediment heat production, the extrapolated present-day temperature of a deeply buried source rock would be overestimated.Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we

  13. A Potential Integrated Water Quality Strategy for the Mississippi River Basin and the Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Suzie Greenhalgh

    2001-01-01

    Full Text Available Nutrient pollution, now the leading cause of water quality impairment in the U.S., has had significant impact on the nation’s waterways. Excessive nutrient pollution has been linked to habitat loss, fish kills, blooms of toxic algae, and hypoxia (oxygen-depleted water. The hypoxic “dead zone” in the Gulf of Mexico is one of the most striking illustrations of what can happen when too many nutrients from inland watersheds reach coastal areas. Despite programs to improve municipal wastewater treatment facilities, more stringent industrial wastewater requirements, and agricultural programs designed to reduce sediment loads in waterways, water quality and nutrient pollution continues to be a problem, and in many cases has worsened. We undertook a policy analysis to assess how the agricultural community could better reduce its contribution to the dead zone and also to evaluate the synergistic impacts of these policies on other environmental concerns such as climate change. Using a sectorial model of U.S. agriculture, we compared policies including untargeted conservation subsidies, nutrient trading, Conservation Reserve Program extension, agricultural sales of carbon and greenhouse gas credits, and fertilizer reduction. This economic and environmental analysis is watershed-based, primarily focusing on nitrogen in the Mississippi River basin, which allowed us to assess the distribution of nitrogen reduction in streams, environmental co-benefits, and impact on agricultural cash flows within the Mississippi River basin from various options. The model incorporates a number of environmental factors, making it possible to get a more a complete picture of the costs and co-benefits of nutrient reduction. These elements also help to identify the policy options that minimize the costs to farmers and maximize benefits to society.

  14. Attributes and origins of ancient submarine slides and filled embayments: examples from the Gulf Coast basin

    Science.gov (United States)

    Morton, Robert

    1993-01-01

    Large submarine slides and associated shelf-margin embayments represent an intermediate member in the continuum of unstable shelf-margin features. On seismic profiles, they may resemble submarine canyons, but are different in their size, morphology, origin, and hydrocarbon exploration potential. Two large Neogene submarine slides, located in the northwestern Gulf Coast Basin, formed on the upper slope and flanks of prominent shelf-margin deltas. The basal detachment surface of each slide is a structural discontinuity that may be misinterpreted as an erosional unconformity and, therefore, misidentified as a stratigraphic boundary separating depositional sequences. Regional stratigraphic correlations indicate that both slides were initiated after the continental platform wa flooded. The condensed sections deposited during the rise in relative sea level contain the basal detachment surfaces. Beyond these observations, the relationships between the slides and sea level fluctuations are uncertain. The shelf-margin embayments created by the slides apparently were partly excavated during periods of lowered relative sea level and were filled during the subsequent relative sea level rise and highstand. Eventually the preslide morphology of the shelf margin was restored by coalesced prograding deltas.

  15. Retrogressive failures recorded in mass transport deposits in the Ursa Basin, Northern Gulf of Mexico

    Science.gov (United States)

    Sawyer, Derek E.; Flemings, Peter B.; Dugan, Brandon; Germaine, John T.

    2009-10-01

    Clay-rich mass transport deposits (MTDs) in the Ursa Basin, Gulf of Mexico, record failures that mobilized along extensional failure planes and transformed into long runout flows. Failure proceeded retrogressively: scarp formation unloaded adjacent sediment causing extensional failure that drove successive scarp formation updip. This model is developed from three-dimensional seismic reflection data, core and log data from Integrated Ocean Drilling Project (IODP) Expedition 308, and triaxial shear experiments. MTDs are imaged seismically as low-amplitude zones above continuous, grooved, high-amplitude basal reflections and are characterized by two seismic facies. A Chaotic facies typifies the downdip interior, and a Discontinuous Stratified facies typifies the headwalls/sidewalls. The Chaotic facies contains discontinuous, high-amplitude reflections that correspond to flow-like features in amplitude maps: it has higher bulk density, resistivity, and shear strength, than bounding sediment. In contrast, the Discontinuous Stratified facies contains relatively dim reflections that abut against intact pinnacles of parallel-stratified reflections: it has only slightly higher bulk density, resistivity, and shear strength than bounding sediment, and deformation is limited. In both facies, densification is greatest at the base, resulting in a strong basal reflection. Undrained shear tests document strain weakening (sensitivity = 3). We estimate that failure at 30 meters below seafloor will occur when overpressure = 70% of the hydrostatic effective stress: under these conditions soil will liquefy and result in long runout flows.

  16. Late Holocene record of sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California

    Science.gov (United States)

    McGann, M.; Paull, C. K.; Herguera, J. C.; Barron, J. A.; Gwiazda, R.; Anderson, K.; Lundsten, E. M.; Edwards, B. D.; Caress, D. W.

    2015-12-01

    Transects of ≤1.5 m-long vibracores obtained with MBARI's ROV Doc Ricketts reveal late Holocene sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California (GOC) (~26.87°N, 111.338°W). Cores were located where layered near-seafloor sediments and subtle bedforms occur in 1793 to 1863 m water depths on the SW flank of the basin using detailed bathymetry and chirp profiles. Color banding was observed in the cores and gamma-density, XRF, grain size, and stable isotope data show that most of the banding is attributed to distal deposition from two turbidities. Distinctive white bands ~4 cm thick are present in three cores dispersed across ~300 m. The white bands are diatom oozes composed primarily of Thalassiothrix longissima as well as lesser abundances of Fragilariopsis doliolus and are probably a result of aggregations of Thalassiothrix-dominated mats that settle through the water column and accumulate on the seafloor. An AMS14C date taken ~3 cm above the white band in one core suggests this event occurred shortly before cal AD 1290±30. The core sites were most likely located beneath an important oceanographic front between nutrient-rich and oligotrophic water masses, probably as the result of well-mixed upper intermediate and surface waters in the mid-GOC and better-stratified tropical waters to the south. This implies the existence of a deeper mixed layer to the N in the mid GOC region most likely controlled by equatorial La Niña events fueled by stronger and more persistent NW winds along the GOC. A substantial reduction in diatom abundance evident by low specimen counts and lack of white bands following this mat-forming event seem to correlate with an abrupt decline in biosiliceous productivity and increases in the abundance of tropical diatoms and silicoflagellates in core MD02-2517 (887 m water depth; western Guaymas Basin slope) at the end of the Medieval Climate Anomaly and transition to the Little Ice Age (~AD 1200-1300).

  17. Methane hydrate-bearing sediments in the Terrebonne basin, northern Gulf of Mexico

    Science.gov (United States)

    Meazell, K.; Flemings, P. B.

    2015-12-01

    We characterize the geological, geophysical, and thermodynamic state of three dipping, hydrate-bearing sands in the Terrebonne mini basin of the northern Gulf of Mexico, and describe three potential drilling locations to sample these hydrate reservoirs. Within the sand bodies, there is a prominent negative polarity seismic reflection (opposite phase to the seafloor reflector) that we interpret to record the boundary between gas hydrate above and free gas below. This anomaly is the Bottom Simulating Reflector (BSR) and the base of the Gas Hydrate Stability Zone (BGHSZ). Above the BSR, reflection seismic data record these reservoirs with a positive polarity while below it, they record the reservoirs with a negative polarity event. Within the sand bodies, seismic amplitudes are generally strongest immediately above and below the BSR and weaken in updip and downdip directions. Beneath the BSR, two of the reservoirs have a strong negative amplitude event that parallels structure that we interpret to record a gas-water contact, while the third reservoir does not clearly record this behavior. Much like the seafloor, the BSR is bowl-shaped, occurring at greatest depths in the northwest and rising near salt bodies in the south and east. In the north east area of previous exploration, the BSR is found at a depth of 2868 meters below sealevel, implying a geothermal gradient of 20.1oC/km for type I hydrates. Logging while drilling data reveal that the sands are composed of numerous thin, hydrocarbon-charged, coarse-grained sediments. Hydrate saturation in these sands is greatest near the BGHSZ. Pressure coring is proposed for three wells that will penetrate the reservoirs at different structural elevations in order to further elucidate reservoir conditions of the sands.

  18. The Influence of Methane Venting on Benthic Foraminiferal Assemblages in Guaymas Basin, Gulf of California

    Science.gov (United States)

    Perez, E.; Herguera, J.; Paull, C.; Ussler, W.; Cortina, A.

    2004-12-01

    Fossil foraminifera are critical for paleoenvironmental reconstructions including the study of past episodes of methane venting from gas hydrate reservoirs. However, the use of benthic foraminifera as indicators of methane release remains controversial and more modern analog data is needed to understand the ecology and isotopic signatures of foraminifera in methane seeps. The objective of this investigation was to characterize the species composition and vertical distribution of living benthic foraminifera (rose Bengal stained) along known gradients of present methane venting in order to gain insight into the ecological tolerances and preferences of benthic foraminifera in methane seeps. Vertical distribution patterns are also important in determining carbon isotope variability. Samples were retrieved along the NE transform margin of the Guaymas Basin in the Gulf of California (about 1,582 m). Suites of ROV cores were collected from beds of living calyptogenid clams, tubeworms, and bacterial mats; from a methane venting site evidenced by a continuous stream of gas bubbles; and from control sites. Our data shows that foraminiferal abundance is lower in the methane-influenced sites than in the control sites. Lowest foraminiferal abundance occurs at the bacterial mats, probably caused by higher levels of sulfide. The assemblage is dominated by calcareous species that are characteristic of other organic-rich, oxygen-poor environments (e.g., Uvigerina peregrina, Bulimina mexicana, Buliminella tenuata, Globobulimina pacifica). The vertical distributions of several species are different from those of conspecifics observed in previous studies of non-seep habitats, with deeper and broader depth ranges for some species at the methane-influenced habitats in this study. Of special interest is the occurrence of Planulina wuellerstorfi, traditionally considered an epifaunal species, at sediment depths of 6 cm and with density maxima between 1 and 3 cm. This may result from

  19. Silicoflagellate Fluxes in Cuenca Alfonso, Mexico During the 2002-2003 El Niño Event

    Science.gov (United States)

    Alvarez, I. G.; Martínez-López, A.; Silverberg, N.

    2007-05-01

    Changes in the circulation and water mass patterns in the Gulf of California are closely associated with changes in atmospheric circulation. At the interannual scale, such changes are associated with events like El Niño, which in the Gulf are characterized by greater penetration of tropical-equatorial water. Subsamples of sediment trap material, collected between January 2002 and February 2004 were examined with the aim of inferring average oceanographic conditions in Cuenca Alfonso, Bahia de La Paz and those during the relatively mild 2002- 03 El Niño. Analysis of the silicoflagellate data series reveals seasonal and interannual relationships between the silicoflagellate fluxes and the dynamics of the water column. Comparison of silicoflagellate fluxes with those of the diatom group indicate that the former represent 0-52% of their combined flux. Both silicate groups generally co-vary but show differences in intensity. Thirteen taxa made up the silicoflagellate species composition. The simultaneous occurrence of Dictyocha epiodon and Distephanus speculum with Dictyocha calida and Dictyocha californica during August 2002 to May 2003, indicated the presence of both California Current Water and Equatorial Surface Water in the area close to Cuenca Alfonso. This favored the increase, mainly in November-December, in the flux of the dominant species, Octactis pulchra (as high as 7 x 106 skeletons m-2 day-1). Spring, on the other hand, was notable for a drop in the total silicoflagellate flux, probably due to the influence of the El Niño event. The subsequent increase in species typical of warm water and the replacement of the dominant species (O. pulchra) by Dictyocha messanensis var messanensis, suggest that the effects of El Niño extended to the fall of 2003.

  20. Modern dinocyst assemblages from the Gulf of Mexico: importance of the basin as potential refuge for late Cenozoic species

    Science.gov (United States)

    Limoges, Audrey; de Vernal, Anne; Londeix, Laurent

    2013-04-01

    Surface sediment samples (0-1 cm) from 44 sites of the Gulf of Mexico and adjacent lagoonal bodies were analyzed for their palynological content in order to document the relationship between organic-walled dinoflagellates cysts (dinocysts) and sea-surface conditions (temperature, salinity, productivity). The analyses also aimed at identifying tracers of toxic algal blooms from sedimentary records. According to redundancy analyses (RDA), the distance to the coast and winter temperature are the most important factors that control cyst distribution in sediment from the study area. They explain respectively 53.2 and 18.6% of the total variance. Our results also demonstrate the richness and thermophilic character of the modern dinocyst assemblages from the Gulf of Mexico. They include taxa typical of tropical and subtropical environments, two potentially toxic species (Polysphaeridium zoharyi and Lingulodinium machaerophorum) as well as species that disappeared from the dinocyst flora of the mid-latitudes of the North Atlantic since the Pliocene period. Worth of mention is the presence of Melitasphaeridium choanophorum as a minor component of assemblages from the north and southwestern Gulf of Mexico, although it was considered extinct by the end of the Pleistocene (> 0.011 Ma). This would imply that this species is currently still living in the study area, and suggest that the basin probably acts as sheltered environment fostering the persistence of endemic species.

  1. Seismic imaging and analysis of source and migration within an integrated hydrocarbon system study: Northern Gulf of Mexico Basin

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Oliver P.; Hood, Kenneth C.; Harrison, Stanley C. [Exxon Exploration Co., Houston, TX (United States); Wenger, Lloyd M. [Exxon Production Research Co., Houston, TX (United States)

    1995-12-31

    The sources for hydrocarbons in young Tertiary reservoirs of the offshore Gulf of Mexico have been enigmatic in the past due to the lack of source rock penetration in offshore drilling. Exxon formed a multidisciplinary team to address source, maturation, and migration in the northern Gulf of Mexico. The study was initiated in a pilot area east of the Mississippi River Delta where the complete hydrocarbon system can be seismically imaged, then expanded to the west across much of the shelf and slope. Hydrocarbons from seeps and reservoirs were geochemically characterized across the entire northern Gulf of Mexico Basin, and direct oil to source rock correlations were made both offshore (in pilot area) and onshore. Modern 2-D and 3-D seismic was used to develop a geologic framework and to map potential offshore source intervals. The major sources identified offshore are centered on the Eocene, Turonian, Tithonian, and Oxfordian, and correspond to second-order sequence stratigraphic transgressions. (author). 1 fig., 1 tab

  2. Sr-Nd isotopes constrain on the deposit history of the basins in the Gulf of Mexico

    Science.gov (United States)

    Li, Y.; Jiang, S.

    2015-12-01

    The Brazos-Trinity Basin IV and Ursa Basin are situated on the northern slope of the Gulf of Mexico. The Ursa basin lies in the center of late Pleistocene Mississippi River deposition, received the sediment deposition during Marine Isotope Stage (MIS) 2- 4. The Brazos-Trinity Basin IV belongs to a part of the Brazos-Trinity fan, it recorded the turbidite deposition and hemiplegic deposition during MIS1- 5. The Sr and Nd isotopic composition of the detrital composition of the sediment in both basins indicates the change of the sediment provenance during the basin-filled process. In the Ursa basin, The difference of 87Sr/86Sr ratio and ɛNd of the detrital component between MIS1,2 (87Sr/86Sr ~ 0.7219 - 0.7321, ɛNd ~ -12 - -13.4) and MIS3,4(87Sr/86Sr ~ 0.7310 - 0.7354, ɛNd ~ -16 - -17.9) is suggested to be related with the provenance change of the detrital particles since LGM. The addition of detrital particle from Appalachians with less radiogenic 87Sr/86Sr and positive ɛNd altered the character of the sediment of the Mississippi River during the last glaciation and deglaciation. In the Brazos-Trinity Basin IV, the narrow range of 87Sr/86Sr and ɛNd indicate that the sediment source of Brazos-Trinity Basin IV had not changed obviously during MIS5e to MIS2, mostly from coastal rivers such as Brazos River, Trinity River and Sabine River. The pre-fan with 87Sr/86Sr ~0.735 and ɛNd ~ -14.5 to -16.9, which is very similar to the deep sediment in the Ursa Basin with 87Sr/86Sr ~0.733 to 0.735 and ɛNd ~ -16 to -18. It is suggested that sediments of the pre-fan of the Brazos-Trinity Basin IV were supplied from the ancestral Mississippi River Delta during the low sea level (MIS 6). During the MIS5, the discharge of Mississippi River is thought switched to its present course, ~300 km to the east.

  3. The Cretaceous-Paleogene boundary deposit in the Gulf of Mexico: Large-scale oceanic basin response to the Chicxulub impact

    Science.gov (United States)

    Sanford, Jason C.; Snedden, John W.; Gulick, Sean P. S.

    2016-03-01

    Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatán Peninsula, the gulf is the premier locale in which to study the near-field geologic effect of a bolide impact. We mapped a thick (decimeter- to hectometer-scale) deposit of carbonate debris at the Cretaceous-Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow-water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact-generated deposition overwhelmed virtually all topography and depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.

  4. Formation mechanisms of heavy oils in the Liaohe Western Depression,Bohai Gulf Basin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The Liaohe Oilfield in the Liaohe Western Depression of the Bohai Gulf Basin is the third-largest oil producing province and the largest heavy oil producing oilfield in China. A total of 65 oil samples,35 rock samples and 36 reservoir sandstone samples were collected and analyzed utilizing conventional geochemical and biogeochemical approaches to unravel the mechanisms of the formation of the heavy oils. Investigation of the oils with the lowest maturity compared with the oils in the Gaosheng and Niuxintuo oilfields indicates no apparent relation between the maturity and physical properties of the heavy oils. It is suggested that the heavy oil with primary origin is not likely the main mechanism re-sponsible for the majority of the heavy oils in the Liaohe Western Slope. The absence and/or depletion of n-alkanes etc.,with relatively low molecular weight and the occurrence of 25-norhopane series in the heavy oils as well as the relatively high acidity of the oils all suggest that the majority of the heavy oils once experienced secondary alteration. The fingerprints of the total scanning fluorescence (TSF) of the inner adsorbed hydrocarbons on the reservoir grains and the included hydrocarbons in fluid inclusions are similar to that of the normal oils in the area but are different from the outer adsorbed and reser-voired free oils at present,further indicating that most of the heavy oils are secondary in origin. Analyses of bacteria (microbes) in 7 oil samples indicate that anaerobic and hyperthermophilic Ar-chaeoglobus sp. are the dominant microbes relevant to oil biodegradation,which coincides with the shallow commercial gas reservoirs containing anaerobic bacteria derived gas in the Gaosheng and Leijia teotonic belts. The biodegradation most likely occurs at the water/oil interface,where the forma-tion water is essential for microbe removal and nutrient transportation. We think that biodegradation,water washing and oxidization are interrelated and are the main

  5. Late Quaternary climatic and oceanographic changes in the Northeast Pacific as recorded by dinoflagellate cysts from Guaymas Basin, Gulf of California (Mexico)

    OpenAIRE

    Price, Andrea M; Mertens, Kenneth; Pospelova, Vera; Pedersen, Thomas F; Ganeshram, Raja S.

    2013-01-01

    A high-resolution record of organic-walled dinoflagellate cyst production in Guaymas Basin, Gulf of California (Mexico) reveals a complex paleoceanographic history over the last ~40 ka. Guaymas Basin is an excellent location to perform high resolution studies of changes in late Quaternary climate and paleo-productivity because it is characterized by high primary productivity, high sedimentation rates, and low oxygen bottom waters. These factors contribute to the deposition and preservation of...

  6. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-05-26

    The principal research effort for Phase 1 (Concept Development) of the project has been data compilation; determination of the tectonic, depositional, burial, and thermal maturation histories of the North Louisiana Salt Basin; basin modeling (geohistory, thermal maturation, hydrocarbon expulsion); petroleum system identification; comparative basin evaluation; and resource assessment. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, and regional cross sections have been prepared. Structure, isopach and formation lithology maps have been constructed, and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs include Upper Jurassic and Cretaceous fluvial-deltaic sandstone facies; shoreline, marine bar and shallow shelf sandstone facies; and carbonate shoal, shelf and reef facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary. Hydrocarbon

  7. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard; Ronald K. Zimmerman

    2005-05-10

    The principal research effort for Year 2 of the project has been data compilation and the determination of the burial and thermal maturation histories of the North Louisiana Salt Basin and basin modeling and petroleum system identification. In the first nine (9) months of Year 2, the research focus was on the determination of the burial and thermal maturation histories, and during the remainder of the year the emphasis has basin modeling and petroleum system identification. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, regional cross sections have been prepared, structure and isopach maps have been constructed, and burial history, thermal maturation history and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and related profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs are mainly Upper Jurassic and Lower Cretaceous fluvial-deltaic sandstone facies and Lower Cretaceous and Upper Cretaceous shoreline, marine bar and shallow shelf sandstone facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary

  8. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2005-03-31

    The principal research effort for Year 2 of the project is the determination of the burial and thermal maturation histories and basin modeling and petroleum system identification of the North Louisiana Salt Basin. In the first six (6) to nine (9) months of Year 2, the research focus is on the determination of the burial and thermal maturation histories and the remainder of the year the emphasis is on basin modeling and petroleum system identification. No major problems have been encountered to date, and the project is on schedule.

  9. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-11-05

    The principal research effort for Year 2 of the project is the determination of the burial and thermal maturation histories and basin modeling and petroleum system identification of the North Louisiana Salt Basin. In the first six (6) to nine (9) months of Year 2, the research focus is on the determination of the burial and thermal maturation histories and the remainder of the year the emphasis is on basin modeling and petroleum system identification. No major problems have been encountered to date, and the project is on schedule.

  10. Fluid transport by solitary waves along growing faults. A field example from the South Eugene Island Basin, Gulf of Mexico

    Science.gov (United States)

    Revil, A.; Cathles, L. M.

    2002-09-01

    The Red Fault system is one of the main growth faults found in the South Eugene Island Basin, a salt withdrawal minibasin located offshore Louisiana, in the Gulf of Mexico. This fault system corresponds to a lateral boundary between fluid overpressured compartments. In addition, there is a set of observations indicating that the Red Fault system exhibits rapid episodic migration of fluids. This fault represents an example of preferential pathway for the upward episodic migration of overpressured hydrocarbons from deep, heavily pressured, compartments on time scales of years. The migrations of fluids into active growing faults could take the form of propagating surges (solitary waves) that propagate upward along the fault planes in a wave-like manner at km/yr. Solitary waves represent a very efficient mechanism for the upward transport of fluids along growth faults in sedimentary basins generating its own permeability. In addition, this mechanism is compatible with the fact that the fault plane is observed to sustain a static pore fluid pressure difference between its two sides. The propagation of solitary waves in active growth faults appears as a fundamental mechanism to understand the nature of upward fast migration of fluids along active growth faults in compartimentalized sedimentary basins.

  11. Imágenes de la "Pasión" en el teatro de Alfonso Sastre

    OpenAIRE

    Aboal Sanjurjo, María Isabel

    2002-01-01

    Presencia bíblica, de la liturgia cristiana, de la divinidad y de lo sacro en la dramaturgia de Alfonso Sastre como elemento vertebrador de la coherencia interna de su teatro a lo largo de toda su trayectoria.

  12. Messinian erosional and salinity crises: View from the Provence Basin (Gulf of Lions, Western Mediterranean)

    OpenAIRE

    Bache, François; Olivet, Jean-Louis; Gorini, Christian; Rabineau, Marina; Baztan, J.; Aslanian, Daniel; Suc, Jean-Pierre

    2009-01-01

    International audience Though the late Miocene “Messinian Salinity Crisis” has been intensely researched along the circum-Mediterranean basins, few studies have focused on the central part of the Mediterranean Basin and, especially, the pre-salt deposits. To improve our knowledge of the Messinian events, it is imperative to better understand this domain. In this study, we provide a more complete understanding of this central domain in the Provence Basin. We were able to recognize: a) thick...

  13. Multiple evidence for methylotrophic methanogenesis as the dominant methanogenic pathway in hypersaline sediments from the Orca Basin, Gulf of Mexico

    Science.gov (United States)

    Zhuang, Guang-Chao; Elling, Felix J.; Nigro, Lisa M.; Samarkin, Vladimir; Joye, Samantha B.; Teske, Andreas; Hinrichs, Kai-Uwe

    2016-08-01

    Among the most extreme habitats on Earth, dark, deep, anoxic brines host unique microbial ecosystems that remain largely unexplored. As the terminal step of anaerobic degradation of organic matter, methanogenesis is a potentially significant but poorly constrained process in deep-sea hypersaline environments. We combined biogeochemical and phylogenetic analyses with incubation experiments to unravel the origin of methane in the hypersaline sediments of Orca Basin in the northern Gulf of Mexico. Substantial concentrations of methane, up to 3.4 mM, coexisted with high concentrations of sulfate from 16 to 43 mM in two sediment cores retrieved from the northern and southern parts of Orca Basin. The strong depletion of 13C in methane (-77‰ to -89‰) points towards a biological source. While low concentrations of competitive substrates limited the significance of hydrogenotrophic and acetoclastic methanogenesis, the presence of non-competitive methylated substrates (methanol, trimethylamine, dimethyl sulfide, dimethylsulfoniopropionate) supported the potential for methane generation through methylotrophic methanogenesis. Thermodynamic calculations demonstrated that hydrogenotrophic and acetoclastic methanogenesis were unlikely to occur under in situ conditions, while methylotrophic methanogenesis from a variety of substrates was highly favorable. Likewise, carbon isotope relationships between methylated substrates and methane suggested methylotrophic methanogenesis was the major source of methane. Stable and radio-isotope tracer experiments with 13C-labeled bicarbonate, acetate and methanol and 14C-labeled methylamine indicated that methylotrophic methanogenesis was the predominant methanogenic pathway. Based on 16S rRNA gene sequences, halophilic methylotrophic methanogens related to the genus Methanohalophilus dominated the benthic archaeal community in the northern basin and also occurred in the southern basin. High abundances of methanogen lipid biomarkers such as

  14. Evolution of the Sedimentary Basin Within the Eastern Eez Polygon at the Gulf of Mexico

    Science.gov (United States)

    Valle, S.; Mortera-Gutierrez, C. A.; Bandy, W. L.; Escobar-Briones, E. G.; Perez, D. A.

    2013-05-01

    This study shows the seafloor structures and magnetic anomalies inside the eastern EEZ polygon at the Gulf of Mexico. The objective of this study is to examine the previous hypothesis of the Gulf of Mexico opening, based on the seafloor magnetic character. Researchers from the "Instituto de Ciencias del Mar y Limnología" at UNAM, collected , multibeam bathymetric data, high-resolution seismic reflection and magnetic profiles along 37 E-W transects during two campaigns on board the UNAM vessel, BO JUSTO SIERRA, SIGSBEE-11 in 2008 and SIGSBEE-13 in 2010. Results of the bathymetry data gathered with the EM300 multibeam echo sounder (Kongsberg) and processed with the software Caraibes from IFREMER has generated a bathymetry chart of seafloor at the Eastern Polygon, and a mosaic of back-scattering images. The high-resolution seismic profiles gathered with the subbottom profiler TOPAS PS-18 (Kongsberg) provide information on the stratigraphy sediment packages across this polygon and across the deep Mississippi Canyon. The magnetic anomalies are reduced from the data gathered with a proton-precession magnetometer, G877 (GEOMETRICS). The anomalies are modeled, based on a N_S rift at the Gulf central sector. The bathymetric chart and reflectivity mosaics of SIGSBEE-11 and SIGSBEE-13 documented the smooth relief of the seabed slope toward the Gulf central sector and abrupt morphological features associated to the meanders of the Mississippi Canyon that trend to the East. The multibeam bathymetry chart shows a relief depth that goes from 2,900 to 3,400 m from north to south. Meanders are observed in the seabed within the Eastern Polygon which is related to turbidity currents from the Mississippi River, and having a trend from west to east. The relief of the canyon shows channels with widths between 400 and 1800 m, and canyon depths up to 80 m. The high-resolution seismic sections, show well defined stratigraphy packages, where clear sediment strata are interrupted by

  15. LANDSCAPE ECOLOGY ASSESSMENT OF THE TENSAS RIVER BASIN, MISSISSIPPI RIVER DELTA REGION, AND GULF OF MEXICO

    Science.gov (United States)

    A group of landscape ecological indicators were applied to biophysical data masked to the Tensas River Basin. The indicators were use to identify and prioritize sources of nutrients in a Mississippi River System sub-basin. Remotely sensed data were used for change detection a...

  16. Postglacial development of the eastern Gulf of Finland: from Pleistocene glacial lake basins to Holocene lagoon systems

    Science.gov (United States)

    Ryabchuk, Daria; Sergeev, Alexander; Kotilainen, Aarno; Hyttinen, Outi; Grigoriev, Andrey; Gerasimov, Dmitry; Anisimov, Mikhail; Gusentsova, Tatiana; Zhamoida, Vladimir; Amantov, Aleksey; Budanov, Leonid

    2016-04-01

    Despite significant amount of data, there are still lots of debatable questions and unsolved problems concerning postglacial geological history of the Eastern Gulf of Finland, the Baltic Sea. Among these problems are: 1) locations of the end moraine and glacio-fluvial deposits; 2) time and genesis of the large accretion forms (spits, bars, dunes); 3) basinwide correlations of trangression/regression culminations with the other parts of the Baltic Sea basin; 4) study of salinity, timing, frequency and intensity of Holocene saline water inflows and their links of sedimentation processes associated with climate change. Aiming to receive new data about regional postglacial development, the GIS analyses of bottom relief and available geological and geophysical data was undertaken, the maps of preQuaternary relief, moraine and Late Pleistocene surfaces, glacial moraine and Holocene sediments thicknesses were compiled. High-resolution sediment proxy study of several cores, taken from eastern Gulf of Finland bottom, allows to study grain-size distribution and geochemical features of glacial lake and Holocene sediments, to reveal sedimentation rates and paleoenvironment features of postglacial basins. Interdisciplinary geoarcheological approaches offer new opportunities for studying the region's geological history and paleogeography. Based on proxy marine geological and coastal geoarcheological studies (e.g. off-shore acoustic survey, side-scan profiling and sediment sampling, on-shore ground-penetrating radar (GPR SIR 2000), leveling, drilling, grain-size analyses and radiocarbon dating and archeological research) detailed paleogeographical reconstruction for three micro-regions - Sestroretsky and Lahta Lowlands, Narva-Luga Klint Bay and Southern Ladoga - were compiled. As a result, new high resolution models of Holocene geological development of the Eastern Gulf of Finland were received. Model calibration and verification used results from proxy geoarcheological research

  17. 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

  18. Benthic macrofaunal colonization patterns and preservation of laminated sediments: Observations in an extreme coastal basin environment in the lower Gulf of California

    Science.gov (United States)

    Herguera, J.; Paull, C. K.; Anderson, K.; Gwiazda, R.; Lundsten, E. M.; Kundz, L.; Edwards, B. D.; McGann, M. L.

    2012-12-01

    New observations and cores obtained with the ROV Doc Ricketts operated from the RV/Western Flyer provide a glimpse into a macrofauna barren sea-floor where laminated sediments are known to accumulate on the sea-floor of Alfonso Basin. This basin, located north of La Paz Bay, Baja California, is known to be an important repository of laminated sediments due to a combination of the relatively high input of terrigenous sediments brought in by summer rains, a moderate to high export productivity from its surface waters, and the very low oxygen concentrations at depth bathed by tropical subsurface waters. These laminated sediments are unique repositories of paleoceanographic and paleoclimatic information for its very high resolution records of past conditions comparable to ice core, tree ring, coral and cave records although spanning continuously much further back in time. However, the paleoceanographic community rarely has had the opportunity to visualize the seafloor surface where these sediments are accumulating and examine the biological abundance patterns in these extreme environments. Here we will show results from ROV Doc Ricketts quantitative video transects providing benthic faunal abundance patterns on the seafloor in these highly oxygen depleted bottom waters. These observations are further compared with the underlying stratigraphy. A coring system carried on the ROV allowed us to replicate cores and to collect a transect of 5 closely spaced cores to evaluate the horizontal extent of the observed variability down-core. We will also show some preliminary results from x-radiographs showing the nature of the laminations and its sediment composition based on elemental analysis on organic carbon, carbonate and biogenic opal analysis. New XRF results from a box core will be used to calibrate its terrigenous components with the historical rainfall record and evaluate its potential to reconstruct summer precipitation patterns in this region.

  19. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2005-04-15

    The principal research effort for the first six months of Year 2 of the project has been petroleum system characterization. Understanding the burial and thermal maturation histories of the strata in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas is important in petroleum system characterization. The underburden and overburden rocks in these basins and subbasins are a product of their rift-related geohistory. Petroleum source rock analysis and thermal maturation and hydrocarbon expulsion modeling indicate that an effective regional petroleum source rock in the onshore interior salt basins, the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin, was the Upper Jurassic Smackover lime mudstone. The Upper Cretaceous Tuscaloosa shale was an effective local petroleum source rock in the Mississippi Interior Salt Basin and a possible local source bed in the North Louisiana Salt Basin. Hydrocarbon generation and expulsion was initiated in the Early Cretaceous and continued into the Tertiary in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin. Hydrocarbon generation and expulsion was initiated in the Late Cretaceous and continued into the Tertiary in the Manila Subbasin and Conecuh Subbasin. Reservoir rocks include Jurassic, Cretaceous and Tertiary siliciclastic and carbonate strata. Seal rocks include Jurassic, Cretaceous and Tertiary anhydrite and shale beds. Petroleum traps include structural and combination traps.

  20. The Sills of Guaymas Basin, Gulf of California: Their Distribution and Seismic Estimates of Their Thickness and Alteration of Intruded Sediments

    Science.gov (United States)

    Lizarralde, D.; Feng, H.; Soule, S. A.; Mortera, C.

    2015-12-01

    A variety of observations, including seismic images and seafloor backscatter and photography, indicate that active igneous sill intrusion into sediments occurs over a broad region, up to 40 km from the plate boundary, in Guaymas Basin in the Gulf of California. The two, young (types of measurements, with ground truthing from drilling results, can provide strong constraints for models of sill/sediment hydro-thermal-chemical dynamics that span a range of environments and age. We also present new seismic images of sill intrusions and subbottom images of features related to gas expulsion that demonstrate some of this range present in Guaymas Basin.

  1. 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

  2. Tectono-Stratigraphy of the Seeps on the Guaymas Basin at the Sonora Margin, Gulf of California, Mexico

    Science.gov (United States)

    Figueroa Albornoz, L. J.; Mortera-Gutierrez, C. A.; Bandy, W. L.; Escobar-Briones, E. G.; Godfroy, A.; Fouquet, Y.

    2013-05-01

    Recently several hydrothermal and gas seeps systems has been located precisely at the Sonora margin within the Guaymas Basin (GB), Gulf of California. Since late 1970's , several marine studies had reported two main hydrothermal systems in the Guaymas Rift (one at the Northern Rift, and other at the Southern Rift) and a cold seeps system at the Satellite Basin in the Sonora-margin lower edge. During the campaign BIG10, onboard the IFREMER vessel, NO L'Atalante, the EM122 echo-sounder log more than 30,000 water column acoustic images, which allows us to create a data base of the bubble plumes active systems on the northern part of the GB and the Sonora Margin. These plumes are the expression on the water column of an active seeps site during the cruise time. These images document the presence of the cold seep activity around the scarp of the Guaymas Transform Fault (GTF), and within the Satellite Basin. Few active plumes are first located off-axis, on both sides of the Northern Rift. Although it is not observed any plume within NR. Sub-bottom profiles and bathymetric data logged during the campaign GUAYRIV10, onboard the UNAM vessel, BO EL PUMA, are analyzed to determine the shallow tectonic-stratigraphy of GB near the Sonora Margin. We analyze 17 high-resolution seismic profiles (13 with NE-SW strike and 3 with NW-SE strike). From this data set, the continental shelf stratigraphy at the Sonora Margin tilts toward the slope, showing 3 low angle unconformities due to tectonics and slope angle changes. The strata slope changes angle up to 60°. However, the constant trans-tension shear along the GTF causes gravitation instability on the slope, generating a few submarine landslides close to the Northern Rift, and the rotation of blocks, tilting toward the shelf. To the north, the GTF splits in two fault escarpments, forming a narrow pull-apart basin, known as Satellite Basin. The submarine canyon from the Sonora River flows through the Satellite Basin into the GB

  3. Targeted technology applications for infield reserve growth: A synopsis of the Secondary Natural Gas Recovery project, Gulf Coast Basin. Topical report, September 1988--April 1993

    Energy Technology Data Exchange (ETDEWEB)

    Levey, R.A.; Finley, R.J.; Hardage, B.A.

    1994-06-01

    The Secondary Natural Gas Recovery (SGR): Targeted Technology Applications for Infield Reserve Growth is a joint venture research project sponsored by the Gas Research Institute (GRI), the US Department of Energy (DOE), the State of Texas through the Bureau of Economic Geology at The University of Texas at Austin, with the cofunding and cooperation of the natural gas industry. The SGR project is a field-based program using an integrated multidisciplinary approach that integrates geology, geophysics, engineering, and petrophysics. A major objective of this research project is to develop, test, and verify those technologies and methodologies that have near- to mid-term potential for maximizing recovery of gas from conventional reservoirs in known fields. Natural gas reservoirs in the Gulf Coast Basin are targeted as data-rich, field-based models for evaluating infield development. The SGR research program focuses on sandstone-dominated reservoirs in fluvial-deltaic plays within the onshore Gulf Coast Basin of Texas. The primary project research objectives are: To establish how depositional and diagenetic heterogeneities cause, even in reservoirs of conventional permeability, reservoir compartmentalization and hence incomplete recovery of natural gas. To document examples of reserve growth occurrence and potential from fluvial and deltaic sandstones of the Texas Gulf Coast Basin as a natural laboratory for developing concepts and testing applications. To demonstrate how the integration of geology, reservoir engineering, geophysics, and well log analysis/petrophysics leads to strategic recompletion and well placement opportunities for reserve growth in mature fields.

  4. "De arauigo en lenguaie castellano": Politica linguistica e traduzione secondo Alfonso X

    Directory of Open Access Journals (Sweden)

    Ruggiero Pergola

    2015-07-01

    Full Text Available Abstract – After Alfonso X’s accession to the throne in mid-13th-century Spain, the translating activity of scientific texts from Arabic changed route: Castilian, instead of Latin, became the language of science. Such a plan, ambitious though risky, was carried out through the writing of the huge Alfonsine corpus of texts, a fundamental contribution to medieval culture, which shaped the picture of Alfonso as “Emperor of Culture”. The aim of this paper is to provide, in the light of recent research, an overall view of the main translators and of the translations of scientific texts from Arabic into Castilian at Alfonso’s court.Abstract – Con l’avvento di Alfonso X nella Spagna della metà del XIII secolo, l’attività traduttiva di testi scientifici dall’arabo conobbe un significativo cambio di rotta: il passaggio dal latino al castigliano come lingua scientifica. Il progetto, ambizioso e rischioso, si realizzò nella redazione dell’immenso corpus alfonsino, fondamentale contributo alla cultura medievale, che ha creato l’immagine di Alfonso “imperatore della cultura”. Obiettivo di questo contributo è offrire, alla luce degli studi più recenti, una visione d’insieme sui principali traduttori e sulle traduzioni di testi scientifici dall’arabo in castigliano realizzate alla corte di Alfonso X.

  5. Upwelling-driven reworking of a MTD's fine-grained plume: an example at the Cariaco Basin/Cariaco Gulf connection.

    Science.gov (United States)

    Aguilar, Iliana; Beck, Christian; Audemard, Franck; Crouzet, Christian; Sabatier, Pierre; Develle, Anne-Lise; Boussafir, Mohammed; Campos, Corina

    2016-04-01

    The Cariaco Basin is a 1400 m-deep and 90 km-wide pull-apart basin, in the south-eastern corner of the Caribbean Sea. To the East, it is connected to the Cariaco Gulf, a 60 km-long, 15 km-wide, and 90 m-deep appendix. Both are E-W elongated and developed upon the south-eastern transform boundary of the Caribbean Plate, an active limit here mainly represented by the El Pilar Fault. The Gulf of Cariaco entrance is a 55 m-deep, and 5 km-wide sill mainly controlled by the large Manzanares River delta, which western foreset slope is facing the Basin's eastern edge. Within this connection area, two particular sedimentary processes have been previously documented: 1) strong seasonal upwelling responsible for the transfer of deep particulate organic matter from the Basin into the Gulf; 2) the recent occurrence, in the Basin, of a fine-grained suspension related to a submarine landslide; this event was detected after the 1997 Cariaco earthquake (Thunell et al., 1999; Lorenzoni et al., 2012) and was related to a slope failure of the Manzanares delta western foreset. From short gravity cores retrieved in the Gulf, we analysed the last millennium of sedimentation (components, transport and settling processes) using classical proxies and physical properties. All parameters led to underline: - a permanent mixed provenance of particulate Organic Matter in the main part of the Gulf: i) in situ and ii) allochtonous; - the occurrence of coarse siliciclastic layers related to flooding from the southern edge of the Gulf; - the occurrence of one peculiar fine-grained siliciclastic layer with a widespread distribution, dated around 1850 AD; - an abrupt increase of open marine influence just after the above-mentioned layer. Concerning the "background" permanent sedimentation, these results confirm the importance of upwelling through the connection between the Gulf and the Basin (transfer of the "allochtonous" O.M.). For the fine-grained silicilastic "event", we could discard a

  6. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2005-10-28

    The principal research effort for Year 2 of the project has been petroleum system characterization and modeling. Understanding the burial, thermal maturation, and hydrocarbon expulsion histories of the strata in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas is important in hydrocarbon resource assessment. The underburden and overburden rocks in these basins and subbasins are a product of their rift-related geohistory. Petroleum source rock analysis and initial thermal maturation and hydrocarbon expulsion modeling indicated that an effective regional petroleum source rock in the onshore interior salt basins and subbasins, the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin, was Upper Jurassic Smackover lime mudstone. The initial modeling also indicated that hydrocarbon generation and expulsion were initiated in the Early Cretaceous and continued into the Tertiary in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin and that hydrocarbon generation and expulsion were initiated in the Late Cretaceous and continued into the Tertiary in the Manila Subbasin and Conecuh Subbasin. Refined thermal maturation and hydrocarbon expulsion modeling and additional petroleum source rock analysis have confirmed that the major source rock in the onshore interior salt basins and subbasins is Upper Jurassic Smackover lime mudstone. Hydrocarbon generation and expulsion were initiated in the Early to Late Cretaceous and continued into the Tertiary.

  7. Down Core Oxygen Isotopic Measurements Of Diatom δ18O From The Guaymas Basin, Gulf Of California

    Science.gov (United States)

    Menicucci, A. J.; Spero, H. J.; Thunell, R.

    2015-12-01

    The Guaymas Basin (GB), Gulf of California (27º53'N, 111º40'W ), is an evaporative basin, with sea surface temperatures (SST) varying between ~30oC (summer) and ~15oC (winter). Productivity is controlled mostly by seasonal upwelling starting in fall (early November) and extending into spring. We are currently analyzing δ18Odiatom from a boxcore (BC-43) using microfluorination (Menicucci, et al. 2013). This boxcore was previously analyzed for UK '37 alkenones and 210Pb activity (Goni, et al. 2001). Residual BC-43 material was sampled at ~2cm intervals. Samples were cleaned to isolate diatoms from other sediments, then equilibrated in water with δ18Owater = +85‰ for 70 hours at 21oC prior to vacuum dehydroxylation and microfluorination. The latter equilibration was done to account for fractionation between covalently bound O and OH- groups during vacuum dehydroxylation, preserving the original δ18Odiatom value. We present δ18Odiatom data from BC-43 samples covering 27cm, equivalent to >225 years of sediment accumulation. δ18O data are converted to temperature (T) based on an existing calibration (Leclerc and Labeyrie 1987). Our data suggest δ18Odiatom values record a T range of 22-18oC, corresponding to the mixed layer depth and the chlorophyll maximum during the fall bloom. These T values are offset from SST data by a mean of 5oC for the same sample intervals. However, δ18Odiatom values from the most recent samples suggest a ~2oC increase in diatom T relative to SST during the last 35 years. This subsurface warming may be due to decreased fall upwelling, increased mixed layer and chlorophyll maximum depths, and/or the timing of the peak diatom bloom. Such correlations are being investigated and the latest results will be presented. Goni, M. A., et al. (2001). Oceanographic considerations for the application of the alkenone-based paleotemperature U-37(K ') index in the Gulf of California. Geochimica Et Cosmochimica Acta 65: 545-557. Leclerc, A. J. and L

  8. Reconstructing hypoxia of the southeastern Gulf of California over the last 18,000 years: sediments of Pescadero Basin

    Science.gov (United States)

    Choumiline, K.; Lyons, T.; Perez-Cruz, L. L.; Escorza-Reyes, M.; Bates, S.

    2014-12-01

    We present the first high-resolution multiproxy reconstruction of the past 18,000 years of oceanic redox variability in the southeastern Gulf of California (GC) and eastern Pacific. The variation in oxygen content prove to be a crucial regulator responsible for changes in biota distribution, water chemistry, physicochemical transformations of dissolved and particulate phases for trace elements in the water column, and formation of authigenic minerals, among other effects. The gravity core DIPAL-III T2 collected aboard the R/V "El Puma" (UNAM) from Pescadero Basin, located within the oxygen minimum zone (OMZ) of the southern GC, was thoroughly studied in terms of C, S, trace element and Fe speciation. After establishing the age-model of the marine sediments, the produced data revealed two clear episodes of peleoceanographic variability, associated with changes in hypoxia. The first period (18.0 - 11.6 cal kyr BP), represented by massive sediments, points to a time with an oxygenated water column and moderate productivity, elucidated by low Corg, high S and a relatively low redox sensitive trace element content (Mo and U). The second (11.6 cal kyr BP - present), easily perceived by a clear lamination pattern, indicates a suboxic/anoxic episode, evidenced by higher Corg, Mo and U, among others. A clear dramatic shift is distinctly observable between these periods for most of the redox-proxies. This shift is related to the changes in sea-level that immediately followed the Last Glacial Maximum, when the ice sheets began to melt. This transitioned Pescadero hydrochemistry from a shallow well-ventilated basin (prior to 11.6 cal kyr BP) to a deep OMZ system. When compared to renowned marine sedimentary records, such as Cariaco and Guaymas basins, some events became more eminent than others. In the particular case of the Younger Dryas (YD) stadial and Bolling Allerod (BA) interstadial, the Corg, S and some trace element patterns were similar among basins even from

  9. Bacterial sulfate reduction in hydrothermal sediments of the Guaymas Basin, Gulf of California, Mexico

    DEFF Research Database (Denmark)

    Weber, A.; Jørgensen, BB

    2002-01-01

    Depth distribution and temperature dependence of bacterial sulfate reduction were studied in hydrothermal surface sediments of the southern trough of the Guaymas Basin at 2000 m water depth. In situ temperatures ranged from 2.8 degreesC at the sediment surface to > 130degreesC at 30 cm depth in t......C. Sulfate reduction was not detected above 100degreesC. (C) 2002 Elsevier Science Ltd. All rights reserved....

  10. Snook (Centropomidae) and grouper (Serranidae) mariculture in the Gulf of Mexico and Caribbean Basin

    OpenAIRE

    Roberts Jr, D

    1989-01-01

    Centropomidae and Serranidae, sometimes collectively misnamed "sea basses", are suitable for aquaculture in pens, ponds, and raceways around the tropical and subtropical latitudes of the world. Western Atlantic Ocean species were recently considered for farming. South Florida, Mexico, Central and South America and the Antilles areas of the Caribbean Basin have extensive areas suitable for farming groupers and snook. Principal species of interest are the common snook (Centropomus undecimalis )...

  11. Relationship between salt diapirism and faulting in the central structural belt of the Dongying sag, Bohai Gulf basin, China

    Institute of Scientific and Technical Information of China (English)

    YU Jianguo; LI Sanzhong; WANG Jinduo; TIMOTHY M Kusky; WANG Xinhong; LU Shengqiang

    2005-01-01

    Many growth faults developed in the Dongying sag of the Jiyang depression of the Bohai Gulf basin, China. These normal growth faults consist of flower-like grabens in the hanging walls of the major faults, accompanied by reverse dragging. The central structural belt is an important structural unit in the Dongying sag, and is divided into a series of small blocks by these faults. These internal blocks can be classified into five structural classes, including parallel blocks, arc-shape blocks, plume-like blocks, ring-radial blocks,and splay blocks. It is shown that these complicated block classes and the "negative flower-like" fault associations in the central structural belt resulted from regional NNW-SSE extension accompanying local salt diapirism and related reverse dragging, rather than strike-slip faulting. On the basis of the diapirism strength, diapers in the central structural belt can be divided into lower salt ridges and pillows, and blind piercing structures. Diapirs are mainly composed of some salts with a little soft mudstone and gypsum. These structures began forming during deposition of the Sha 3 member and terminated during deposition of the Guangtao formation.

  12. Data collection for cooperative water resources modeling in the Lower Rio Grande Basin, Fort Quitman to the Gulf of Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Passell, Howard David; Pallachula, Kiran (GRAM, Inc., Albuquerque, NM); Tidwell, Vincent Carroll; Villalobos, Joshua (Texas A& M University); Piccinni, Giovanni (Texas A& M University); Brainard, James Robert; Gerik, Thomas (Texas A& M University); Morrison, Wendy (Texas A& M University); Serrat-Capdevila, Aleix (University of Arizona); Valdes, Juan (University of Arizona); Sheng, Zhuping (Texas A& M University); Lovato, Rene (Instituto Mexicano de Tecnologia del Agua); Guitron, Alberto (Instituto Mexicano de Tecnologia del Agua); Ennis, Martha Lee; Aparicio, Javier (Instituto Mexicano de Tecnologia del Agua); Newman, Gretchen Carr (GRAM, Inc., Albuquerque, NM); Michelsen, Ari M. (Texas A& M University)

    2004-10-01

    Water resource scarcity around the world is driving the need for the development of simulation models that can assist in water resources management. Transboundary water resources are receiving special attention because of the potential for conflict over scarce shared water resources. The Rio Grande/Rio Bravo along the U.S./Mexican border is an example of a scarce, transboundary water resource over which conflict has already begun. The data collection and modeling effort described in this report aims at developing methods for international collaboration, data collection, data integration and modeling for simulating geographically large and diverse international watersheds, with a special focus on the Rio Grande/Rio Bravo. This report describes the basin, and the data collected. This data collection effort was spatially aggregated across five reaches consisting of Fort Quitman to Presidio, the Rio Conchos, Presidio to Amistad Dam, Amistad Dam to Falcon Dam, and Falcon Dam to the Gulf of Mexico. This report represents a nine-month effort made in FY04, during which time the model was not completed.

  13. Sulfur, carbon, and oxygen isotope variations in submarine hydrothermal deposits of Guaymas Basin, Gulf of California, USA

    Science.gov (United States)

    Peter, J.M.; Shanks, Wayne C., III

    1992-01-01

    Sulfur, carbon, and oxygen isotope values were measured in sulfide, sulfate, and carbonate from hydrothermal chimney, spire, and mound samples in the southern trough of Guaymas Basin, Gulf of California, USA. ??34S values of sulfides range from -3.7 to 4.5%. and indicate that sulfur originated from several sources: 1. (1) dissolution of 0??? sulfide contained within basaltic rocks, 2. (2) thermal reduction of seawater sulfate during sediment alteration reactions in feeder zones to give sulfide with positive ??34S, and 3. (3) entrainment or leaching of isotopically light (negative-??34S) bacteriogenic sulfide from sediments underlying the deposits. ??34S of barite and anhydrite indicate sulfur derivation mainly from unfractionated seawater sulfate, although some samples show evidence of sulfate reduction and sulfide oxidation reactions during mixing within chimneys. Oxygen isotope temperatures calculated for chimney calcites are in reasonable agreement with measured vent fluid temperatures and fluid inclusion trapping temperatures. Hydrothermal fluids that formed calcite-rich chimneys in the southern trough of Guaymas Basin were enriched in 18O with respect to seawater by about 2.4??? due to isotopic exchange with sedimentary and/or basaltic rocks. Carbon isotope values of calcite range from -9.6 to -14.0??? ??34CpDB, indicating that carbon was derived in approximately equal quantities from the dissolution of marine carbonate minerals and the oxidation of organic matter during migration of hydrothermal fluid through the underlying sediment column. Statistically significant positive, linear correlations of ??34S, ??34C, and ??18O of sulfides and calcites with geographic location within the southern trough of Guaymas Basin are best explained by variations in water/rock ( w r) ratios or sediment reactivity within subsurface alteration zones. Low w r ratios and the leaching of detrital carbonates and bacteriogenic sulfides at the southern vent sites result in relatively

  14. Evidence of a Volcanic Rifted Margin: A Velocity Model for the Gulf of Mexico Basin Opening Seismic Refraction Project

    Science.gov (United States)

    Duncan, Mark; Van Avendonk, Harm; Christeson, Gail

    2013-04-01

    The Gulf of Mexico Basin Opening marine seismic refraction project (GUMBO) is a study of the lithological composition and structural evolution of the Gulf of Mexico (GoM) that uses Ocean Bottom Seismometer (OBS) data from four transects in the Northern GoM. Our analysis focuses specifically on line 4, the easternmost transect which extends over ~500 km from the continental shelf near Gainesville across the Florida Escarpment to the deep water GoM. Shear-wave first arrivals are picked from eleven out of the 39 OBS shot records in order to perform a tomographic inversion. The resulting shear-wave velocity model is used in conjunction with a previously constructed P-wave model to plot Vs as a function of Vp. We compare the Vp-Vs relationship with empirical velocities from the literature for the purpose of constraining lithological composition along GUMBO Line 4, and we make an interpretation of the structural evolution of the eastern GoM. The crust landward of the Florida Escarpment appears from our comparison with external data to be normal continental crust. Velocities plot within ~100 -200 m/s from compilations of seismic velocities (Vp = 6.2 - 7.0 km/sec; Vs = 3.8 - 4.0 km/sec) of felsic crystalline basement. Seaward of the escarpment, velocities in the oceanic crust are anomalously high (Vp = 6.5 - 7 km/sec; Vs = 4.0 - 4.6 km/sec). A possible explanation for this is that early-Jurassic basaltic sheet flows formed subaerially, reducing the vesicularity found in basalts that have cooled rapidly underwater. An increased magnesium and iron content could also account for these high velocities, and would suggest that the oceanic crust formed at higher mantle potential temperatures than previously thought. Geometrically, the transition from thick to thin crust near the Florida Escarpment on GUMBO line 4 is relatively narrow, which may be explained by rapid continental breakup with little stretching of continental crust. Alternatively, this margin may also have

  15. The Ups and Downs of extension-parallel folding: Stratigraphic evolution of a constrictional rift basin during oblique opening of the Gulf of California

    Science.gov (United States)

    Seiler, Christian; Quigley, Mark; Fletcher, John

    2013-04-01

    Oblique opening of the Gulf of California provides a unique opportunity to study the mode of deformation in transtensional rift systems. Sedimentation in rifted basins is primarily controlled by the characteristics of the basin-bounding fault and the available sediment supply, and can thus be used as a proxy to understand tectonic processes during oblique shear. Transtensional basins are generally seen as composites between rift and pull-apart basins, with facies distributions that are controlled by interacting normal and strike-slip faults. Yet, transtensional shear may also be accommodated by more distributed constrictional strain that is not localised along fault zones. The Santa Rosa basin, located in the Sierra San Felipe of northern Baja California, is one of a series of transtensional syn-rift basins along the oblique-divergent plate boundary of the northern Gulf of California. The basin represents an asymmetric half-graben in the hanging wall of the Santa Rosa detachment, a low-angle normal fault with ~4-5km of E- to SE-directed displacement. The basin-fill dips NW into the detachment and displays form lines that mimic the corrugations of the detachment. The basin is broadly sigmoidal in shape, is truncated in the south by a dextral transfer zone and pinches out against the hanging wall basement in the north. The syn-rift stratigraphy is dominated by a sequence of alluvial fans shed from the hanging wall and footwall that interfinger with fine grained playa deposits. Stratigraphic analysis reveals systematic basin-scale variations in facies distributions, both along and across the axis of the basin. In a transverse direction, the basin-fill records a fining-upward cycle from conglomerate at the base to alternating sandstone-mudstone in the depocentre, which in turn interfingers with the proximal fault-scarp facies of the Santa Rosa detachment. Facies patterns also vary parallel to the basin axis even though finite displacement on the detachment was

  16. ASSESSING AND FORECASTING, BY PLAY, NATURAL GAS ULTIMATE RECOVERY GROWTH AND QUANTIFYING THE ROLE OF TECHNOLOGY ADVANCEMENTS IN THE TEXAS GULF COAST BASIN AND EAST TEXAS

    Energy Technology Data Exchange (ETDEWEB)

    William L. Fisher; Eugene M. Kim

    2000-12-01

    A detailed natural gas ultimate recovery growth (URG) analysis of the Texas Gulf Coast Basin and East Texas has been undertaken. The key to such analysis was determined to be the disaggregation of the resource base to the play level. A play is defined as a conceptual geologic unit having one or more reservoirs that can be genetically related on the basis of depositional origin of the reservoir, structural or trap style, source rocks and hydrocarbon generation, migration mechanism, seals for entrapment, and type of hydrocarbon produced. Plays are the geologically homogeneous subdivision of the universe of petroleum pools within a basin. Therefore, individual plays have unique geological features that can be used as a conceptual model that incorporates geologic processes and depositional environments to explain the distribution of petroleum. Play disaggregation revealed important URG trends for the major natural gas fields in the Texas Gulf Coast Basin and East Texas. Although significant growth and future potential were observed for the major fields, important URG trends were masked by total, aggregated analysis based on a broad geological province. When disaggregated by plays, significant growth and future potential were displayed for plays that were associated with relatively recently discovered fields, deeper reservoir depths, high structural complexities due to fault compartmentalization, reservoirs designated as tight gas/low-permeability, and high initial reservoir pressures. Continued technology applications and advancements are crucial in achieving URG potential in these plays.

  17. Aptian ‘Shale Gas’ Prospectivity in the Downdip Mississippi Interior Salt Basin, Gulf Coast, USA

    Science.gov (United States)

    Hackley, Paul C.; Valentine, Brett J.; Enomoto, Catherine B.; Lohr, Celeste D.; Scott, Krystina R.; Dulong, Frank T.; Bove, Alana M.

    2016-01-01

    This study evaluates regional ‘shale gas’ prospectivity of the Aptian section (primarily Pine Island Shale) in the downdip Mississippi Salt Basin (MSB). Previous work by the U.S. Geological Survey estimated a mean undiscovered gas resource of 8.8 trillion cubic feet (TCF) in the chronostratigraphic-equivalent Pearsall Formation in the Maverick Basin of south Texas, where industry has established a moderately successful horizontal gas and liquids play. Wells penetrating the downdip MSB Aptian section at depths of 12,000-15,000 ft were used to correlate formation tops in a 15-well cross-section extending about 200 miles (mi) east-southeastward from Adams Co. to Jackson Co. Legacy cuttings from these wells were analyzed for thermal maturity and source rock quality. Bitumen reflectance (n=53) increases with increasing present-day burial depth in the east-central study area from 1.0% to 1.7%. As the Aptian section shallows in Adams Co. to the west, bitumen Ro values are higher (1.7-2.0%), either from relatively greater heat flux or greater mid-Cenomanian uplift and erosion in this area. Total organic carbon (TOC) content ranges 0.01-1.21 and averages 0.5 wt.% (n=51); pyrolysis output (S2; n=51) averages 0.40 mg HC/g rock, indicating little present-day hydrocarbon-generative potential. Bitumen reflectance is preferred as a thermal maturity parameter as Tmax values are unreliable. Normalized X-ray diffraction (XRD) mineral analyses (n=26) indicate high average clay abundance (53 wt.%) relative to quartz (29%) and carbonate (18%). Mineral content shows a spatial relationship to an Appalachian orogen clastic sediment source, with proximal high clay and quartz and distal high carbonate content. Clastic influx from the Appalachian orogen is confirmed by detrital zircon U-Pb ages with dominant Grenville and Paleozoic components [105 ages from a Rodessa sandstone and 112 ages from a Paluxy (Albian) sandstone]. Preliminary information from fluid inclusion microthermometry

  18. Glacial to Holocene terrigenous organic matter input to sediments from Orca Basin, Gulf of Mexico — A combined optical and biomarker approach

    OpenAIRE

    Meckler, A. N.; Schubert, C. J.; Hochuli, P. A.; Birgit Plessen; Birgel, D.; Flower, B. P.; K.-U. Hinrichs; Haug, G.H.

    2008-01-01

    In this study we assessed changes in the contribution of terrigenous organic matter (OM) to the Gulf of Mexico over the course of the last deglaciation (the last 25 kyr). To this end, we combined optical kerogen analyses with bulk sedimentary, biomarker, and compound-specific carbon isotope analyses. Samples were obtained from core MD02-2550 from Orca Basin (2249 m water depth at 26°56.77N, 91°20.74W) with temporal resolution ranging from multi-decadal to millennial-scale, depending on the pr...

  19. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2004-10-28

    The objectives of the study are: to perform resource assessment of the in-place deep (>15,000 ft) natural gas resource of the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling and to use the petroleum system based resource assessment to estimate the volume of the in-place deep gas resource that is potentially recoverable and to identify those areas in the interior salt basins with high potential to recover commercial quantities of the deep gas resource. The principal research effort for Year 1 of the project is data compilation and petroleum system identification. The research focus for the first nine (9) months of Year 1 is on data compilation and for the remainder of the year the emphasis is on petroleum system identification.

  20. 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.

  1. Basin Analysis of the Mississippi Interior Salt Basin and Petroleum System Modeling of the Jurassic Smackover Formation, Eastern Gulf Coastal Plain

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Ernest A.

    2003-02-06

    The project objectives are improving access to information for the Mississippi Interior Salt Basin by inventorying data files and records of the major information repositories in the region, making these inventories easily accessible in electronic format, increasing the amount of information available on domestic sedimentary basins through a comprehensive analysis of the Mississippi Interior Salt Basin, and enhancing the understanding of the petroleum systems operating in the Mississippi Interior Salt Basin.

  2. Early Diagenetic Effects on Magnetic Properties in Laminated Sediments from the Southern Gulf of California

    Science.gov (United States)

    Perez-Cruz, L. L.; Fucugauchi, J. U.

    2015-12-01

    Effects of early diagenesis on the magnetic mineralogy in marine sediments have long been investigated, including oxidation/reduction reactions, magnetic dilution, formation of iron sulfides and oxides, magnetization acquisition mechanisms and reliability of paleomagnetic record. In this study, we analyze the mineral magnetic properties and downcore magnetite contents on Late Holocene sediments from Alfonso Basin, Gulf of California. Volcanic-derived terrigenous and biogenic input represents major sediment sources, with low-oxygen environments allowing preservation of finely laminated sequences. Susceptibility logs show high values at the top sediments and small amplitude low frequency fluctuations downcore. Magnetic hysteresis loops indicate low coercivity saturation characteristic of magnetites and low-Ti titanomagnetites, with varying paramagnetic contributions. Intensity of natural remanent magnetization, saturation isothermal magnetization and coercivity parameters show similar patterns with depth. In particular, the susceptibility log shows magnetic enhancement in the upper sediments of up to 4 times the values along the core. Below 40 cm depth the exponential decay relates to diagenetic changes and magnetite authigenesis associated with organic matter oxidative decomposition during dewatering and compaction occurring above the iron reduction zone. Results support presence of recent and old dissolution fronts resulting from preservation of enriched PSD/MD magnetite in between the dissolution fronts. Oxidation/reduction conditions in turn relate to climatic and water/sediment interface factors that control dissolution processes, which occur in sub-oxic to anoxic conditions.

  3. "Who's afraid of Virginia Woolf?" : Edward Albee y su influencia en el teatro de Alfonso Paso

    OpenAIRE

    Espejo Romero, Ramón

    1998-01-01

    Edward Albee's Who's Afraid of Virginia Woolf? (1962) is, without any doubt, one of the most significant American dramas of the 1960s. The fame of Albee's highly controversial play soon reached Spain, for a Spanish version of it was successfully presented in Madrid in 1966. An unexpected consequence of the play's sudden popularity was the influence it exerted on the dramatic works of Spanish playwright Alfonso Paso. This paper studies the way in which Who's Afraid of Virginia Woolf?'s Spanish...

  4. Recent Advances in Modeling Phosphorus and Nitrogen Delivery to the Gulf of Mexico and Implications for Managing Nutrients n the Mississippi River Basin

    Science.gov (United States)

    Alexander, R. B.; Smith, R. A.; Schwarz, G. E.; Boyer, E. W.; Nolan, J. V.; Brakebill, J. W.

    2008-12-01

    Although the increased availability of reactive nutrients in past decades has benefited society via food and energy production, the corresponding rise in nutrient loadings to aquatic ecosystems is of particular concern, especially in many estuaries globally where increased nutrient loads have contributed to eutrophic conditions. In the United States, elevated riverine nutrients have contributed to stressed trophic conditions in a majority of estuaries, including the shallow coastal waters of the Louisiana shelf in the northern Gulf of Mexico, where both nitrogen and phosphorus loadings are recognized as contributing to seasonal hypoxic conditions. Advances in geospatial modeling of nitrogen and phosphorus sources and transport in the Mississippi and Atchafalaya River Basins (MARB), as reported in a recent U.S. Geological Survey (USGS) study, provide important information to support improved assessments and management of nutrient loadings to the northern Gulf of Mexico. We summarize the findings of this study and discuss the implications for managing nutrient sources in the MARB. The study reveals important differences in the sources and aquatic transport of nitrogen and phosphorus that affect delivery to the Gulf. Although agricultural sources contribute a majority of the delivered nutrients to the Gulf, corn and soybean cultivation is the largest contributor of nitrogen whereas phosphorus originates primarily from animal manure on pasture and rangelands. Atmospheric deposition is the second leading source of nitrogen, with urban sources contributing relatively small quantities of both nutrients. Furthermore, we find that both nitrogen and phosphorus delivery to the Gulf is controlled by hydrological and biogeochemical processes (e.g., water travel time, denitrification, storage) that scale with stream size, although phosphorus also displays large local- and regional-scale differences in delivery caused by reservoir trapping. The importance of these processes

  5. Holocene late Pleistocene non-tropical carbonate sediments and tectonic history of the western rift basin margin of the southern Gulf of California

    Science.gov (United States)

    Halfar, Jochen; Godinez-Orta, Lucio; Goodfriend, Glenn A.; Mucciarone, David A.; Ingle, James C.; Holden, Peter

    2001-10-01

    Using high-resolution seismic reflection profiling and dating of (1) shallow marine vibracores and (2) sediments collected from uplifted marine terraces we reconstruct the tectonic history and sediment accumulation patterns of Holocene to late Pleistocene warm-temperate to subtropical carbonates in the southern Gulf of California, Mexico. The study was conducted in the vicinity of La Paz where carbonates form along the fault bounded narrow western shelf of the tectonically active Gulf of California rift basin. The non-tropical nature of the setting is responsible for (1) poor cementation of the bioclastic carbonates, and (2) a composition which is dominated by rhodoliths (coralline red algae), corals and mollusks. Unrimmed carbonate flats forming in small pocket bays and a rhodolith bioherm, which has a surface area of more than 20 km 2 and is up to 16 m thick, constitute the major carbonate factories. Holocene carbonate accumulation rates were deduced from seismic and core data and are highest on the rhodolith bioherm (260 cm/ka) and in subtidal zones of pocket bays (210 cm/ka), and lowest on the inner and middle shelf (100 cm/ka). Taken together, rates of carbonate accumulation are intermediate in magnitude between higher rates recorded in fully tropical carbonate settings and lower rates typical of cool-water carbonates. Seismic reflection profiles demonstrate that Isla Espiritu Santo in the center of the study area is a west dipping fault block, which is tectonically influenced by two distinct faults, the La Paz and Espiritu Santo faults. The latter fault accommodates at least 700 m of east-side down normal offset, and forms a steep eastern escarpment leading into the La Paz slope basin. Some of the sediments produced in the shallow carbonate factories of the narrow La Paz shelf are transported across this escarpment and are redeposited in the slope basin at a water depth of 750 m. Uranium-series dates of marine terraces exposed on Isla Espiritu Santo indicate

  6. RESOURCE ASSESSMENT OF THE IN-PLACE AND POTENTIALLY RECOVERABLE DEEP NATURAL GAS RESOURCE OF THE ONSHORE INTERIOR SALT BASINS, NORTH CENTRAL AND NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-04-16

    The University of Alabama and Louisiana State University have undertaken a cooperative 3-year, advanced subsurface methodology resource assessment project, involving petroleum system identification, characterization and modeling, to facilitate exploration for a potential major source of natural gas that is deeply buried (below 15,000 feet) in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas. The project is designed to assist in the formulation of advanced exploration strategies for funding and maximizing the recovery from deep natural gas domestic resources at reduced costs and risks and with minimum impact. The results of the project should serve to enhance exploration efforts by domestic companies in their search for new petroleum resources, especially those deeply buried (below 15,000 feet) natural gas resources, and should support the domestic industry's endeavor to provide an increase in reliable and affordable supplies of fossil fuels. The principal research effort for Year 1 of the project is data compilation and petroleum system identification. The research focus for the first nine (9) months of Year 1 is on data compilation and for the remainder of the year the emphasis is on petroleum system identification. The objectives of the study are: to perform resource assessment of the in-place deep (>15,000 ft) natural gas resource of the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling and to use the petroleum system based resource assessment to estimate the volume of the in-place deep gas resource that is potentially recoverable and to identify those areas in the interior salt basins with high potential to recover commercial quantities of the deep gas resource. The project objectives will be achieved through a 3-year effort. First, emphasis is on petroleum system identification and characterization in the

  7. HYPOXIA IN THE GULF OF MEXICO: ASSESSING AND MANAGING RISKS FROM NONPOINT SOURCE POLLUTANTS IN THE MISSISSIPPI RIVER BASIN

    Science.gov (United States)

    . Hypoxia is the condition in which dissolved oxygen levels are below that necessary to sustain most animal life. The largest zone of oxygen depletion in U.S. coastal waters is found in the northern Gulf of Mexico (NGOM) on the Louisiana/Texas continental shelf. In response to...

  8. Origin and early development of the Gulf of Mexico Basin based on 15-second record seismic in the Louisiana Shelf and Upper Slope

    Energy Technology Data Exchange (ETDEWEB)

    Hall, D.J. [Excalibur Interpretation Co., Houston, TX (United States)

    1996-09-01

    A 4x4 mile grid of new 15-second record seismic data covering the entire Louisiana shelf and upper slope reveals new insights into the deep structure of the Gulf of Mexico Basin. Noteworthy is the absence of evidence for major horst and graben basement faulting predicted in some models for the early Gulf under the shelf. Instead, the basement appears generally smooth, with a reasonably conformable early section 1 to 1.5 seconds thick immediately overlying it. This suggests either that the basement was formed as lower plate continental crust (in a simple shear detachment fault scenario, below the brittle-ductile crustal transition) or as oceanic crust similar to that observed under autochthonous salt in the Perdido fold belt. If the latter is correct, the edge of oceanic crust needed to reconstruct the sea-floor spreading history may nearly coincide with the current northern limit of the sub-salt hydrocarbon play, possibly because the play location depends on 3-4 km thick salt originally deposited in the area under the southern shelf. The southern limit of thick LouAnn salt is related to depositional factors (evaporation, oceanic circulation, etc.) rather than to underlying crustal type. An unresolved question is the nature of the section overlying the smooth basement event. Both deepwater Lower Cretaceous (chalks, marts ?) and Eagle Mills deepwater equivalents (shales) are plausible interpretations.

  9. Dinoflagellate cysts as indicators of millennial scale climatic and oceanographic variability in Guaymas Basin, Gulf of California (Mexico) during the Late Quaternary

    Science.gov (United States)

    Price, Andrea M.; Mertens, Kenneth N.; Pospelova, *Vera; Pedersen, Thomas F.; Ganeshram, Raja S.

    2015-04-01

    A high-resolution record of organic-walled dinoflagellate cyst production in Guaymas Basin, Gulf of California (Mexico) reveals a complex paleoceanographic history over the last ~40 ka. Guaymas Basin is an excellent location to perform high resolution studies of changes in Late Quaternary climate and paleo-productivity because it is characterized by high primary productivity, high sedimentation rates, and low oxygen bottom waters. These factors contribute to the deposition and preservation of laminated sediments throughout large portions of core MD02-2515. This is one of the first studies in the Northeast Pacific to document dinoflagellate cyst production at a centennial to millennial scale throughout the Late Quaternary. Based on the cyst assemblages three major dinoflagellate cyst zones were established, and roughly correspond to Marine Isotope Stages 1 to 3. The most dominant dinoflagellate cyst taxa found throughout the core were Brigantedinium spp. and Operculodinium centrocarpum. Dansgaard-Oeschger event 8 is observed in the dinoflagellate cyst record, and is characterized by an increase in warm water taxa such as Spiniferites pachydermus. Other intervals of interest are the Younger Dryas where cooler sea-surface conditions are not recorded, and the Holocene which is characterized by the consistent presence of warm water species Stelladinium reidii, Tuberculodinidum vancampoae, Bitectatodinium spongium and an increase in Quinquecuspis concreta. Changes in cyst assemblages, concentrations and species diversity, along with geochemical data reflect major orbital to millennial-scale climatic and oceanographic changes. Keywords: Dansgaard-Oeschger events; dinoflagellate cyst; Gulf of California; late Quaternary climate change; upwelling; Younger Dryas.

  10. Gulf Coast Geology (GCG) Online

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A large percentage of the present and future energy resources of the United States reside in the Gulf of Mexico Basin, one of the major hydrocarbon producing areas...

  11. El retorno a lo humano en Gravedad, de Alfonso Cuarón

    Directory of Open Access Journals (Sweden)

    Arturo Morales-Campos

    2016-01-01

    Full Text Available Bajo una perspectiva socio-semiótica, el filme Gravedad (2013, de Alfonso Cuarón, presenta, dentro de su estructura significante, signos de diferente código (visual, musical, sonoro, lingüístico, etc., que se agrupan en núcleos semánticos. Estos núcleos remiten a una microestructura fundamental de polos opuestos y complementarios: el ambiente científico-tecnológico en el que se desarrolla la diégesis del texto visual encuentra, una vez y otra, su contrario en una posibilidad de retorno a lo humano esencial: la vida.

  12. Does a strong pycnocline impact organic-matter preservation and accumulation in an anoxic setting? The case of the Orca Basin, Gulf of Mexico

    Science.gov (United States)

    Tribovillard, Nicolas; Bout-Roumazeilles, Viviane; Sionneau, Thomas; Serrano, Jean Carlos Montero; Riboulleau, Armelle; Baudin, François

    2009-01-01

    The Orca Basin (an intraslope depression located in the Gulf of Mexico) collects sedimentary particles of terrestrial origin (clastic and organic particles mainly supplied by the Mississippi River) and of marine origin (biogenic productivity). The basin is partly filled with dense brines leached from salt diapirs cropping out on the sea floor, and is permanently stratified. A strong pycnocline induces anoxic bottom conditions, expectedly favorable to organic matter (OM) preservation. Here, we report on OM in the upper 750 cm below sea floor of Core MD02-2552 (Holocene). The organic content is dominated by marine-derived amorphous OM. The organic assemblage is unexpectedly degraded to some extent, which may be accounted for by a relatively long residence time of organic particles at the halocline-pycnocline at ˜2240 m. Thus the organic particles are temporarily trapped and kept in contact with the dissolved oxygen-rich overlying water mass. Lastly, the land-derived organic fraction shows co-variations with the land-derived clay mineral supply.

  13. Modified Gulf of California model for South Georgia,north Scotia Ridge, and implications for the Rocas Verdes back-arc basin, southern Andes

    Science.gov (United States)

    Alabaster, T.; Storey, B. C.

    1990-06-01

    New field mapping and an integrated trace element and Nd isotopic study have been undertaken on the Jurassic-Cretaceous Larsen Harbour Complex on the island of South Georgia, recognized as a displaced part of the southern Andes ensialic, autochthonous Rocas Verdes marginal basin. Five basalt groups (Groups I-V) are identified from trace element data; initial Nd isotopic compositions suggest that they are derived from only two sources. Magmas produced during early stages of continental lithospheric attenuation (Groups I-III) were derived by varying degrees of partial melting and fractional crystallization from a large ion lithophile element (LILE)-enriched, low-ɛNd mantle source relative to normal (N)-type mid-ocean ridge basalt (MORB). Magmas produced during later stages of rifting (Groups IV and V) were, however, derived from a high-ɛNd asthenospheric mantle source similar to N-type MORB, unaffected by earlier LILE enrichment. Our data do not concur with previous suggestions that the Larsen Harbour Complex and, by implication, the Rocas Verdes formed in a supra-subduction-zone setting. On the basis of geologic and geochemical evidence, we favor basin formation along an oblique-slip margin akin to that of the Gulf of California.

  14. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-09-30

    The objectives of the study were: (1) to perform resource assessment of the thermogenic gas resources in deeply buried (>15,000 ft) natural gas reservoirs of the onshore interior salt basins of the north central and northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling; and (2) to use the petroleum system based resource assessment to estimate the volume of the deep thermogenic gas resource that is available for potential recovery and to identify those areas in the interior salt basins with high potential for this thermogenic gas resource. Petroleum source rock analysis and petroleum system characterization and modeling, including thermal maturation and hydrocarbon expulsion modeling, have shown that the Upper Jurassic Smackover Formation served as the regional petroleum source rock in the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin. Thus, the estimates of the total hydrocarbons, oil, and gas generated and expelled are based on the assumption that the Smackover Formation is the main petroleum source rock in these basins and subbasins. The estimate of the total hydrocarbons generated for the North Louisiana Salt Basin in this study using a petroleum system approach compares favorably with the total volume of hydrocarbons generated published by Zimmermann (1999). In this study, the estimate is 2,870 billion barrels of total hydrocarbons generated using the method of Schmoker (1994), and the estimate is 2,640 billion barrels of total hydrocarbons generated using the Platte River software application. The estimate of Zimmermann (1999) is 2,000 to 2,500 billion barrels of total hydrocarbons generated. The estimate of gas generated for this basin is 6,400 TCF using the Platte River software application, and 12,800 TCF using the method of Schmoker (1994). Barnaby (2006) estimated that the total gas volume generated for this basin ranges from 4,000 to 8,000 TCF. Seventy

  15. Historia de los MSS BH 133 y 128 de Alfonso de Palencia

    Directory of Open Access Journals (Sweden)

    Durán Barceló, Javier

    2012-07-01

    Full Text Available El investigador que inspeccione los volúmenes UCM BH MSS 133 y 128 de Alfonso de Palencia encontrará un buen número de marcas y cotas librarias acumuladas a lo largo de su historia. Como veremos en este trabajo, estas signaturas tienen su correspondencia en los inventarios y catálogos de la biblioteca del Colegio de San Ildefonso desde 1720, 1745, 1800 y 1878. Además, la historia de estos manuscritos se puede rastrear hasta la fundación del Colegio mediante un examen analítico de los primitivos inventarios de la librería ildefonsina incluso más allá del año 1517.The researcher who inspects volumes UCM BH MSS 133 and 128 of Alfonso de Palencia will encounter a great variety of old call numbers and librarian marks accumulated throughout their history. As we will find out in this paper, these call numbers have also a parallel existence in the inventories and catalogues of the Library of the Colegio de San Ildefonso produced since 1720, 1745, 1800 y 1878. But the history of these manuscripts can be also traced back to the foundation of the College, as it is demonstrated by an analytical examination of the earlier Library inventories as far as 1517 and beyond.

  16. Evidence For Decadal and Century Scale Climate and Oceanic Variability in the Guaymas Basin, Gulf of California, Over the Last Millenium

    Science.gov (United States)

    Pineda, L.; Ravelo, A. C.; Aiello, I. W.; Stewart, Z.; Sauthoff, W.

    2015-12-01

    Linda Pineda1Ana Christina Ravelo2Ivano Aiello3Zach Stewart2Wilson Sauthoff2 Earth and Planetary Sciences Department, UCSC Ocean Sciences Department, UCSC Moss Landing Marine Lab Natural climate change affects coastal water resources, human land use, and marine biological productivity. In particular, the seasonal migration of the Intertropical Convergence Zone (ITCZ) is influenced by changes in global-scale temperature and pressure gradients and is responsible for spatial changes in summertime rainfall in Mesoamerica impacting regional water resources and the strength of upwelling. In October 2014, aboard the Research Vessel El Puma, a 3.9 meter long core (G14-P12) was recovered from the Northeast flank of the Guaymas Basin in the Gulf of California within the oxygen minimum zone (27˚52.11'N, 111˚41.51'W, water depth of 677m) to investigate changes in seasonal upwelling and Central Mexico rainfall over the last ~1000 years. The age model was developed using Pb210, C14 and lamination counting. The time interval includes the Little Ice Age and the Medieval Warm Period. Biological productivity and precipitation proxy records were produced using an X-Ray Fluorescence (XRF) core-scanner and a color line scanner to generate a record of bulk chemistry and color reflectance. The records indicate marked decadal and centennial scale variability in the lithologic composition of the sediment superimposed on millimeter-scale variability that reflects the presence of seasonally laminated sediments. Nitrogen isotopic and nitrogen weight % measurements were used, in combination with the scanned data, to interpret changes in nitrate utilization and biological productivity. These new records will have broad implications on the link between regional coastal environmental conditions in the Gulf of California and global climate change.

  17. A review on tectonic record of strain buildup and stress release across the Andean forearc along the Gulf of Guayaquil-Tumbes basin (GGTB) near Ecuador-Peru border

    OpenAIRE

    2013-01-01

    Gravimetric and geologic data show that the reactivation of the Neogene Interandean depression and/or the ~75 - 65 Ma ophiolite suture into the modern dynamic of the Andes controlled the Gulf of Guayaquil Tumbes basin (GGTB) location and evolution during the past 1.8 - 1.6 Myr at least. Depending on whether the remobilization occurred along the in- terandean depression or the ophiolite suture, the GGTB evolved trough pure or simple shear mechanisms, respectively. Because the GGTB exhibits an ...

  18. The role of the cold sector of extratropical cyclones in setting atmospheric mean state features of the Gulf Stream basin.

    Science.gov (United States)

    Vannière, Benoît; Czaja, Arnaud; Dacre, Helen; Woollings, Tim

    2016-04-01

    The mechanism by which the Gulf Stream SST front anchors a band of precipitation on its warm edge is still a matter of debate and little is known about how synoptic activity contributes to shape precipitation mean state pattern. In this talk, we introduce a new indicator for the cold sector of extratropical storms based on low-level PV. This indicator is used in ERA interim data to separate the cold sector contribution to precipitation and vertical wind from the contribution of the rest of the storm. We find that cold sector precipitation forms a band following the SST front closely. In contrast, the enhanced ascent on the warm edge of the front is set primarily by the warm sector and cannot be directly related to the precipitation band as proposed by previous studies. Numerical sensitivity experiments of an extratropical cyclone passing over different sets of SST further confirms that the anchoring effect of the SST front on precipitation comes exclusively from the cold sector. These results lead us to revisit the atmospheric boundary layer model proposed to describe air-sea interactions over the Gulf-Stream SST gradient. Finally, we explore the role of the cold sector convection in restoring baroclinicity in the wake of an extratropical cyclone.

  19. Continental breakup and the dynamics of rifting in back-arc basins: The Gulf of Lion margin

    Science.gov (United States)

    Jolivet, Laurent; Gorini, Christian; Smit, Jeroen; Leroy, Sylvie

    2015-04-01

    Deep seismic profiles and subsidence history of the Gulf of Lion margin reveal an intense stretching of the distal margin and strong postrift subsidence, despite weak extension of the onshore and shallow offshore portions of the margin. We revisit this evolution from the geological interpretation of an unpublished multichannel seismic profile and other published geophysical data. We show that an 80 km wide domain of thin lower continental crust, the "Gulf of Lion metamorphic core complex," is present in the ocean-continent transition zone and exhumed mantle makes the transition with oceanic crust. The exhumed lower continental crust is bounded upward and downward by shallow north dipping detachments. The presence of exhumed lower crust in the deep margin explains the discrepancy between the amount of extension deduced from normal faults in the upper crust and total extension. We discuss the mechanism responsible for exhumation and present two scenarios: the first one involving a simple coupling between mantle extension due to slab retreat and crustal extension and the second one involving extraction of the lower crust and mantle from below the margin by the southeastward flow of hot asthenosphere in the back-arc region during slab rollback. In both scenarios, the combination of Eocene crustal thickening related to the Pyrenees, the nearby volcanic arc, and a shallow lithosphere-asthenosphere boundary weakened the upper mantle and lower crust enough to make them flow southeastward. The overall hot geodynamic environment also explains the subaerial conditions during most of the rifting stage and the delayed subsidence after breakup.

  20. Adjustment of the basin-scale circulation at 26° N to variations in Gulf Stream, deep western boundary current and Ekman transports as observed by the Rapid array

    Directory of Open Access Journals (Sweden)

    S. A. Cunningham

    2009-04-01

    Full Text Available The Rapid instrument array across the Atlantic Ocean along 26° N provides unprecedented monitoring of the basin-scale circulation. A unique feature of the Rapid array is the combination of full-depth moorings with instruments measuring temperature, salinity, pressure time series at many depths with co-located bottom pressure measurements so that dynamic pressure can be measured from surface to bottom. Bottom pressure measurements show a zonally uniform rise (and fall of bottom pressure of 0.015 dbar on a 5 to 10 day time scale, suggesting that the Atlantic basin is filling and draining on a short time scale. After removing the zonally uniform bottom pressure fluctuations, bottom pressure variations at 4000 m depth against the western boundary compensate instantaneously for baroclinic fluctuations in the strength and structure of the deep western boundary current so there is no basin-scale mass imbalance resulting from variations in the deep western boundary current. After removing the mass compensating bottom pressure, residual bottom pressure fluctuations at the western boundary just east of the Bahamas balance variations in Gulf Stream transport. Again the compensation appears to be especially confined close to the western boundary. Thus, fluctuations in either Gulf Stream or deep western boundary current transports are compensated in a depth independent (barotropic manner very close to the continental slope off the Bahamas. In contrast, compensation for variations in wind-driven surface Ekman transport appears to involve fluctuations in both western basin and eastern basin bottom pressures, though the bottom pressure difference fluctuations appear to be a factor of 3 too large, perhaps due to an inability to resolve small bottom pressure fluctuations after removal of larger zonal average, baroclinic, and Gulf Stream pressure components. For 4 tall moorings where time series dynamic height (geostrophic pressure profiles can be estimated from

  1. Late Quaternary climatic and oceanographic changes in the Northeast Pacific as recorded by dinoflagellate cysts from Guaymas Basin, Gulf of California (Mexico)

    Science.gov (United States)

    Price, Andrea M.; Mertens, Kenneth N.; Pospelova, Vera; Pedersen, Thomas F.; Ganeshram, Raja S.

    2013-01-01

    A high-resolution record of organic-walled dinoflagellate cyst production in Guaymas Basin, Gulf of California (Mexico) reveals a complex paleoceanographic history over the last ~40 ka. Guaymas Basin is an excellent location to perform high resolution studies of changes in late Quaternary climate and paleo-productivity because it is characterized by high primary productivity, high sedimentation rates, and low oxygen bottom waters. These factors contribute to the deposition and preservation of laminated sediments throughout large portions of the core MD02-2515. In this study, we document dinoflagellate cyst production at a centennial to millennial scale throughout the late Quaternary. Based on the cyst assemblages, three dinoflagellate cyst zones were established and roughly correspond to Marine Isotope Stages (MISs) 1 to 3. MISs 1 and 3 are dominated by cysts of heterotrophic dinoflagellates, whereas MIS 2 is characterized by enhanced variability and a greater proportion of cysts produced by autotrophic taxa. The most dominant dinoflagellate cyst taxa found throughout the core were Brigantedinium spp. and Operculodinium centrocarpum. Dansgaard-Oeschger event 8 is observed in the dinoflagellate cyst record where it is characterized by an increase in warm taxa, such as Spiniferites pachydermus. Other intervals of interest are the Younger Dryas where warmer conditions are recorded and the Holocene which is characterized by the consistent presence of tropical species Stelladinium reidii, Tuberculodinidum vancampoae, Bitectatodinium spongium, and an increase in Quinquecuspis concreta. Changes in cyst assemblages, concentrations, and species diversity, along with geochemical data reflect major orbital to millennial-scale climatic and oceanographic changes.

  2. Garra mondica, a new species from the Mond River drainage with remarks on the genus Garra from the Persian Gulf basin in Iran (Teleostei: Cyprinidae).

    Science.gov (United States)

    Sayyadzadeh, Golnaz; Esmaeili, Hamid Reza; Freyhof, Jörg

    2015-01-01

    Garra mondica, new species, from the Mond River drainage in Iran is distinguished from its congeners by having 7½ branched dorsal-fin rays; the breast, belly and back in front of the dorsal-fin origin naked and 9+8 branched caudal-fin rays. Garra mondica is also distinguished from all other congeners in the Persian Gulf basin, except an unidentified species from the Kol River, by having two fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region. The identity of G. gymnothorax, a nominal species from the Karun River drainage, and G. crenulata, a nominal species from Central Iran, are discussed. Garra populations examined from the Karun have a unique mtDNA COI barcode sequence, but their diagnostic characters are not consistent with the description and syntypes of G. gymnothorax. G. crenulata is considered as a synonym of G. rufa. Two populations of Garra from the Kol River have a sequence of the COI barcode region very similar to G. mondica, but cannot be identified as G. mondica and their identity cannot be resolved here.

  3. Garra mondica, a new species from the Mond River drainage with remarks on the genus Garra from the Persian Gulf basin in Iran (Teleostei: Cyprinidae).

    Science.gov (United States)

    Sayyadzadeh, Golnaz; Esmaeili, Hamid Reza; Freyhof, Jörg

    2015-01-01

    Garra mondica, new species, from the Mond River drainage in Iran is distinguished from its congeners by having 7½ branched dorsal-fin rays; the breast, belly and back in front of the dorsal-fin origin naked and 9+8 branched caudal-fin rays. Garra mondica is also distinguished from all other congeners in the Persian Gulf basin, except an unidentified species from the Kol River, by having two fixed, diagnostic nucleotide substitutions in the mtDNA COI barcode region. The identity of G. gymnothorax, a nominal species from the Karun River drainage, and G. crenulata, a nominal species from Central Iran, are discussed. Garra populations examined from the Karun have a unique mtDNA COI barcode sequence, but their diagnostic characters are not consistent with the description and syntypes of G. gymnothorax. G. crenulata is considered as a synonym of G. rufa. Two populations of Garra from the Kol River have a sequence of the COI barcode region very similar to G. mondica, but cannot be identified as G. mondica and their identity cannot be resolved here. PMID:26624737

  4. La doctrina sobre el poder del príncipe en Alfonso Hojeda de Mendoza

    Directory of Open Access Journals (Sweden)

    Salustiano de DIOS

    2009-12-01

    Full Text Available RESUMEN: Alfonso Hojeda fue un notable canonista sevillano que en 1576 publicó en Venecia un libro acerca de los beneficios eclesiásticos. La obra se divide en dos partes: la primera está dedicada a argumentar en contra de la pluralidad de beneficios en una misma persona, de acuerdo con los decretos tridentinos de reforma, mientras la segunda trata en cambio de la compatibilidad de beneficios mediante dispensa papal. Los propios términos en que se manifiestan las dos partes ya están indicando las contradicciones en que ha de moverse el autor, difíciles de salvar. La doctrina de la causa es, además de la distinción entre órdenes normativos, la principal herramienta conciliatoria para Hojeda. El papa está desligado del derecho positivo o humano, pues de otro modo no podría dispensar, o privilegiar, mas sólo puede hacerlo con justa causa.ABSTRACT: Alfonso Hojeda de Mendoza was an outstanding canonist that in 1576 published a book in Venice on the eclesiástica benefits. The book is divided into two parts: the first one is devoted to argue against the plurality of benefits in the same person, according to Trento's decrees, while the second one deals, however, with the compatibility of benefits by the Pope's dispense. The own terms in which both parts are expressed reveal the contradictions, in which the author must move, always difficult to avoid. The doctrine of the cause, as well as the distinction among normative orders, is the main conciliatory tool for Hojeda. The Pope is unlinked to human or positive right, otherwise he could not dispense or privilege, however he can only do it for a just cause.

  5. Thermal and geochemical influences on microbial biogeography in the hydrothermal sediments of Guaymas Basin, Gulf of California.

    Science.gov (United States)

    McKay, Luke; Klokman, Vincent W; Mendlovitz, Howard P; LaRowe, Douglas E; Hoer, Daniel R; Albert, Daniel; Amend, Jan P; Teske, Andreas

    2016-02-01

    Extreme thermal gradients and compressed metabolic zones limit the depth range of microbial colonization in hydrothermally active sediments at Guaymas Basin. We investigated the physicochemical characteristics of this ecosystem and their influence on microbial community structure. Temperature-related trends of δ(13)C values of methane and dissolved inorganic carbon from 36 sediment cores suggest in situ thermal limits for microbial anaerobic methane oxidation and organic carbon re-mineralization near 80°C and 100°C respectively. Temperature logging probes deposited in hydrothermal sediments for 8 days demonstrate substantial thermal fluctuations of up to 25°C. Putative anaerobic methanotroph (ANME) populations dominate the archaeal community, transitioning from ANME-1 archaea in warm surficial sediments towards ANME-1 Guaymas archaea as temperatures increase downcore. Since ANME archaea performing anaerobic oxidation of methane double on longer time scales (months) compared with relatively rapid in situ temperature fluctuations (hours to days), we conclude that ANME archaea possess a high tolerance for short-term shifts in the thermal regime.

  6. Trace Metal Distribution and Speciation in Pore Water of Hydrothermal Sediments From the Guaymas Basin, Gulf of California

    Science.gov (United States)

    Morales-Villafuerte, M.; Ortega-Osorio, A.; Wheat, G.; Seewald, J.

    2004-12-01

    Thirteen sediment cores were collected through out direct sampling with the MBARI/ ROV "Tiburon" in the southern trough of the Guaymas Basin in March 2003. Pore water samples from regular 2.5 cm intervals of sediment cores were extracted onboard by centrifugation. The supernatants were collected in clean polystyrene vials and stored at 4° C until analytical work on shore. Dissolved Fe, Mn, Cu, Pb, Zn and Ni concentrations in extracted fluid samples were analyzed by direct injection of atomic absorption spectrometry. Four zones in the hydrothermal field were classified according to their physical characteristics. A core located away from the influence of active vents was recovered as a background site. The second zone is characterized by low temperatures (4.2-80° C) and sediments saturated in hydrocarbons. Sulfides formation and higher temperatures (4-166° C) were observed in the third zone. Precipitation of carbonates on top of the sediment characterizes the fourth zone. Concentration of trace metals at the water-sediment interface appears to be the highest, probably due to metal precipitation from the hydrothermal plume, followed by diffusion into the pore water. A decrease in concentration is observed between 5-12 cm depth, suggesting that biological activity is consuming essential metals (zone of bioturbation). Metal concentrations in zones where sulfide phases are rich, exhibit smaller values in pore water (Fe=2.4-3.8 μ mol/kg, Cu=0.6-0.8 μ mol/kg, Pb=1.2-1.5 μ mol/kg, Zn=0.4-0.5 μ mol/kg and Ni= 3.4-4.4 μ mol/kg) relative to samples located at hydrocarbon sites (Fe= 2.7-11.4, Cu= 0.7-1.0 μ mol/kg, Pb= 1.2-2.2 μ mol/kg, Zn= 0.4-0.7 μ mol/kg and Ni= 3.4-5.2 μ mol/kg). At sulfide zones, pH and Eh conditions help to precipitate their stable sulfides as opposed to the hydrocarbon areas, where conditions are not favorable for sulfide formation due to the absence of H2S. In general, Fe concentrations in pore water are lower than that of Mn, very likely

  7. Volcanics in the Gulf Coast [volcanicg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The volcanic provinces are modified after Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in Volume J, The...

  8. Salt Diapirs in the Gulf Coast [gcdiapirg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Locations and shapes of salt diapirs were modified after the New Orleans Geological Society map, Salt tectonism of the U.S. Gulf Coast Basin (compiled by J.A....

  9. Fault Zones in the Gulf Coast [gcfltzoneg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data represent major fault zones as indicated on Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in...

  10. Archaeal and anaerobic methane oxidizer communities in the Sonora Margin cold seeps, Guaymas Basin (Gulf of California).

    Science.gov (United States)

    Vigneron, Adrien; Cruaud, Perrine; Pignet, Patricia; Caprais, Jean-Claude; Cambon-Bonavita, Marie-Anne; Godfroy, Anne; Toffin, Laurent

    2013-08-01

    Cold seeps, located along the Sonora Margin transform fault in the Guaymas Basin, were extensively explored during the 'BIG' cruise in June 2010. They present a seafloor mosaic pattern consisting of different faunal assemblages and microbial mats. To investigate this mostly unknown cold and hydrocarbon-rich environment, geochemical and microbiological surveys of the sediments underlying two microbial mats and a surrounding macrofaunal habitat were analyzed in detail. The geochemical measurements suggest biogenic methane production and local advective sulfate-rich fluxes in the sediments. The distributions of archaeal communities, particularly those involved in the methane cycle, were investigated at different depths (surface to 18 cm below the sea floor (cmbsf)) using complementary molecular approaches, such as Automated method of Ribosomal Intergenic Spacer Analysis (ARISA), 16S rRNA libraries, fluorescence in situ hybridization and quantitative polymerase chain reaction with new specific primer sets targeting methanogenic and anaerobic methanotrophic lineages. Molecular results indicate that metabolically active archaeal communities were dominated by known clades of anaerobic methane oxidizers (archaeal anaerobic methanotroph (ANME)-1, -2 and -3), including a novel 'ANME-2c Sonora' lineage. ANME-2c were found to be dominant, metabolically active and physically associated with syntrophic Bacteria in sulfate-rich shallow sediment layers. In contrast, ANME-1 were more prevalent in the deepest sediment samples and presented a versatile behavior in terms of syntrophic association, depending on the sulfate concentration. ANME-3 were concentrated in small aggregates without bacterial partners in a restricted sediment horizon below the first centimetres. These niche specificities and syntrophic behaviors, depending on biological surface assemblages and environmental availability of electron donors, acceptors and carbon substrates, suggest that ANME could support

  11. Texto e imagen en España de sol a sol de Alfonso Armada

    Directory of Open Access Journals (Sweden)

    Champeau, Geneviève

    2011-06-01

    Full Text Available España de sol a sol (2001 by Alfonso Armada gives an example of the development of the «travel narrative» genre in Spain today. Faced with the «end of travel» (Marc Augé, he proposes a renovation of the perception of the familiar by travelling across Spain and Portugal and by substituting «endotic» (Georges Pérec for exotic.The poetics in the narrative differs greatly from that by travelling writers of «social realism», in the Spain of the sixties. Interpretation replaces information, the poetic image prevails over the referential function of language, and polysemy, omnipresent intertexuality and metatextuality play an important part. The change also affects the links between text and image, which are now more complementary than redundant. Playing with stereotypes, the photography actively contributes to establishing argumentative strategies meant to make the reader-viewer adhere to the message, all while affirming itself as an autonomous aesthetic experience.España de sol a sol (2001 de Alfonso Armada proporciona una muestra de la evolución del género del «libro de viajes» en la España contemporánea. Ante la imposibilidad del viaje (Marc Augé, propone renovar la percepción de lo familiar recorriendo el espacio nacional y sustituyendo el «endotismo» (Georges Pérec al exotismo. La poética del viaje que propone el relato difiere profundamente de la de los escritores viajeros del «realismo social», en la España de los años sesenta, anteponiendo la interpretación a la información, la imagen poética a la función referencial del lenguaje, cultivando la polisemia, una intertextualidad masiva y una reflexión metatextual. Distintos son también los vínculos que se establecen entre texto e imagen, de complementariedad más que de redundancia. La fotografía participa activamente, por la reelaboración de tópicos, del dispositivo argumentativo destinado a favorecer la adhesión del lector-espectador al mensaje y se afirma

  12. Adjustment of the basin-scale circulation at 26° N to variations in Gulf Stream, deep western boundary current and Ekman transports as observed by the Rapid array

    Directory of Open Access Journals (Sweden)

    S. A. Cunningham

    2009-10-01

    Full Text Available The Rapid instrument array across the Atlantic Ocean along 26° N provides unprecedented monitoring of the basin-scale circulation. A unique feature of the Rapid array is the combination of full-depth moorings with instruments measuring temperature, salinity, pressure time series at many depths with co-located bottom pressure measurements so that dynamic pressure can be measured from surface to bottom. Bottom pressure measurements show a zonally uniform rise (and fall of bottom pressure of 0.015 dbar on a 5 to 10 day time scale, suggesting that the Atlantic basin is filling and draining on a short time scale. After removing the zonally uniform bottom pressure fluctuations, bottom pressure variations at 4000 m depth against the western boundary compensate instantaneously for baroclinic fluctuations in the strength and structure of the deep western boundary current so there is no basin-scale mass imbalance resulting from variations in the deep western boundary current. After removing the mass compensating bottom pressure, residual bottom pressure fluctuations at the western boundary just east of the Bahamas balance variations in Gulf Stream transport. Again the compensation appears to be especially confined close to the western boundary. Thus, fluctuations in either Gulf Stream or deep western boundary current transports are compensated in a depth independent (barotropic manner very close to the continental slope off the Bahamas. In contrast, compensation for variations in wind-driven surface Ekman transport appears to involve fluctuations in both western basin and eastern basin bottom pressures, though the bottom pressure difference fluctuations appear to be a factor of 3 too large, perhaps due to an inability to resolve small bottom pressure fluctuations after removal of larger zonal average, baroclinic, and Gulf Stream pressure components. For 4 tall moorings where time series dynamic height (geostrophic pressure profiles can be estimated from

  13. José Miguel Jiménez receives Order of Alfonso X the Wise

    CERN Multimedia

    CERN Bulletin

    2016-01-01

    On 12 July 2016, José Miguel Jiménez, Head of CERN Technology Department, has been awarded a spanish civil decoration — an encomienda — of the Order of Alfonso X the Wise (see here), for his outstanding experience in the field of research and scientific management in particle physics.   The ceremony took place at the National Library of Spain, in Madrid, on 12 July. From left: Marcial Marín Hellín, Secretary of State for Education, Professional training and Universities; José María Lassalle Ruiz, Secretary of State for Culture; Íñigo Méndez de Vigo y Montojo, Ministry of Education, Culture and Sport; José Miguel Jiménez, Head of CERN Technology Department; Carmen Vela Olmo, Secretary of State for Investigation, Development and Innovation. (Photo: ©Javier Martínez de la Torre, M...

  14. Geological Characteristics of Gas Accumulation Combination of Persian Khuff Formation in Gulf Basin%波斯湾盆地Khuff组成藏组合地质特征

    Institute of Scientific and Technical Information of China (English)

    李浩武; 童晓光

    2012-01-01

    The combination of source rock, reservoir and cap rock in the Persian Khuff Formation is the most important gas accumulation combination in the Persian Gulf basin. Both Permian Khuff carbonate and interlayer anhydrite consist in the basic elements of gas accumulation combination of Persian Khuff Formation. The Silurian Qusaiba Formation hot shale is the source rock, with wide distribution, high TOC and moderate thermal maturity at late Craterous. The time of trap formation is earlier than that of hydrocarbon generation window,and many basement faults take vertically a good passageway for hydrocarbon migration from Qusaiba hot shale to Unayzah sandstone and the Unayzah sandstone make a lateral migration passageway. The cyclically deposited anhydrite and carbonates act the good cap rock and high quality reservoir. The Khuff Formation reservoir rocks with good original property are composed of oolite, pellete, hiodetritus packstone and grainstone,with good moldic pore and interparticle pore. The action of leaching and dolomitization greatly improved the reservoir pore at later stage. In most area, the faults do not make the cap rock loss the sealing, so little gas is lost. The potential area of gas exploration is in the overlay area of Qusaiba'Formation mature source rock and interlayer anhydrite, including West Arabian sub-basin, central- east part of Widyan-Mesopotamia sub-basin, northwest of Persian Gulf, and southern area of Ghawar oil field. It is paid more attention in the future to identify the big traps with low closure. Additionally,for the high economy limit of exploration and development in the Middle East, the production for small hydrocar- bon reservoirs need the support of high oil price.%Khuff组成藏组合是波斯湾盆地最重要的天然气成藏组合,二叠系Khuff组储层和层间硬石膏盖层构成了成藏组合的基本要素。下志留统Qusaiba段热页岩是Khuff组成藏组合的烃源岩,其分布广、有机质含量高,在晚

  15. Escape tectonism in the Gulf of Thailand: Paleogene left-lateral pull-apart rifting in the Vietnamese part of the Malay Basin

    DEFF Research Database (Denmark)

    Fyhn, Michael B.W.; Boldreel, Lars Ole; Nielsen, Lars H

    2010-01-01

    The Malay Basin represents one of the largest rift basins of SE Asia. Based on a comprehensive 2-D seismic database tied to wells covering mainly Vietnamese acreage, the evolution of the Vietnamese part of the basin is outlined and a new tectonic model is proposed for the development of the basin....... The Vietnamese part of the Malay Basin comprises a large and deep Paleogene pull-apart basin formed through Middle or Late Eocene to Oligocene left-lateral strike-slip along NNW-trending fault zones. The Tho Chu Fault Zone constitutes a significant Paleogene left-lateral strike-slip zone most likely associated...... with SE Asian extrusion tectonism. The fault zone outlines a deep rift that widens to the south and connects with the main Malay Basin. In the central northern part of the basin, a series of intra-basinal left-lateral fracture zones are interconnected by NW to WNW-trending extensional faults and worked...

  16. La Segunda Partida de Alfonso X el Sabio y la tradición occidental de los specula principum

    OpenAIRE

    Nanu, Irina

    2013-01-01

    La presente tesis doctoral, titulada La «Segunda Partida» de Alfonso X el Sabio y la tradición occidental de los «specula principum», no es ni pretende ser una monografía tradicional sobre la materia política de la «Segunda Partida»; ni, mucho menos, un repertorio exhaustivo y minucioso de los «specula principum» occidentales, que recogen, en sus enseñanzas, las múltiples inquietudes del pensamiento político medieval, desde el convecionalismo del neoplatonismo agustiniano hasta el naturalism...

  17. El mito de Orestes en Les mouches de Jean-Paul Sartre y El pan de todos de Alfonso Sastre: La necesidad de la acción

    Directory of Open Access Journals (Sweden)

    L. Rovecchio Antón L.

    2012-08-01

    Full Text Available ENIn Les mouches and El pan de todos, Jean-Paul Sartre and Alfonso Sastre speak about the mythological figure of Orestes to reveal the problems of their society. In this article I will focus on the analysis of these two plays and, more specifically, the question of the necessity of the action, which is closely linked with human freedom. A freedom based on choosing a way that leads to direct action or passivity. A choice that, in turn, becomes the essence of human being.Keywords: Jean-Paul Sartre, Alfonso Sastre, Orestes, freedom, action.  ESEn Les mouches y El pan de todos, Jean-Paul Sartre y Alfonso Sastre discurren sobre la figura mitológica de Orestes para revelarnos los problemas de la sociedad que les rodea. En este artículo me centraré en el análisis de estas dos piezas teatrales y, más concretamente, en la cuestión de la necesidad de la acción, que está íntimamente ligada con la libertad del hombre. Una libertad que se basa en la elección de un camino que lleva a la actuación directa o a la pasividad. Una elección que, a su vez, se convierte en la esencia del ser humano.Palabras claves: Jean-Paul Sartre, Alfonso Sastre, Orestes, libertad, acción.

  18. High-resolution seismic stratigraphy of a late Pleistocene submarine fan ponded by salt-withdrawal mini-basins on the Gulf of Mexico continental slope

    Energy Technology Data Exchange (ETDEWEB)

    Winker, C.D.

    1996-12-31

    The late Pleistocene Brazos-Trinity Fan, a structurally ponded fan completely exposed and undisturbed on the seafloor, was mapped with a combination of conventional and high-resolution seismic data. This fan occupies three salt-withdrawal mini-basins (1, 2, 4) and a graben (3), each filled with an onlapping package consisting of alternating bedded and non-bedded units evident on high-resolution data. Basins 1--3 are filled to their topographic spill points; the onlap-fill succession of each is incised by a channel system which bypassed sediment to the next basin(s) downdip. Seismic continuity generally increases distally in the system and within individual basins, believed to reflect the increasing prevalence of turbidity currents over high-density sediment gravity flows.

  19. Simulated Changes in the Ratios of Nutrients Delivered to the Gulf of Mexico in Response to Changes in the Nutrient Sources of Inland Watersheds of the Mississippi River Basin

    Science.gov (United States)

    Alexander, R. B.; Smith, R. A.; Schwarz, G. E.; Boyer, E. W.

    2005-05-01

    Increases in riverine nitrogen loads to the northern Gulf of Mexico have contributed to increased hypoxia in the coastal waters of the Louisiana shelf during the past several decades. Nitrogen is the most limiting nutrient for algal production in these waters, however, Mississippi River nutrient loads entering the Gulf are closely balanced with seasonally shifting Redfield ratios. Moreover, state concerns over phosphorus, which is generally more limiting to primary production in inland waters, may contribute to an increased emphasis on future phosphorus reductions to meet designated use requirements in state waters. Currently, knowledge is lacking about how nutrient ratios in Mississippi River loads are likely to respond to future changes in nutrient sources in inland watersheds. An improved understanding is initially needed of the major sources and processes in the Mississippi River Basin (MRB) that control both phosphorus and nitrogen delivery to the Gulf. Earlier modeling studies of nutrients in the MRB have focused primarily on nitrogen with little attention to phosphorus. Here, we develop a Spatially Referenced Regression on Watershed Attributes (SPARROW) model of mean-annual total phosphorus (TP) loads for streams in the MRB. The SPARROW model links measurements of TP loads in streams with geographic data on phosphorus sources (e.g., fertilizer, livestock wastes, urban sources) and properties of the landscape that influence transport (e.g., climate, topography, vegetation, soils, water routing). The model employs mechanistic components and mass balance constraints within a formal parameter-estimation structure to empirically quantify the sources, attenuation rates, and transport of phosphorus in the terrestrial and aquatic ecosystems of the MRB. The model was used to quantify the interior watersheds and nutrient sources that contribute to phosphorus delivery to the Gulf. Using a previously estimated SPARROW nitrogen model for the MRB, we computed Redfield

  20. Deglacial nitrogen isotope changes in the Gulf of Mexico: Evidence from bulk sedimentary and foraminifera-bound nitrogen in Orca Basin sediments

    OpenAIRE

    A. N. Meckler; Ren, H.; Sigman, D. M.; Gruber, N.; Birgit Plessen; Schubert, C. J.; Haug, G.H.

    2011-01-01

    Constraining variations in marine N(2)-fixation over glacial-interglacial timescales is crucial for determining the role of the marine nitrogen cycle in modifying ocean productivity and climate, yet paleo-records from N2-fixation regions are sparse. Here we present new nitrogen isotope (delta(15)N) records of bulk sediment and foraminifera test-bound (FB) nitrogen extending back to the last ice age from the oligotrophic Gulf of Mexico (GOM). Previous studies indicate a substantial terrestrial...

  1. El asta de la lanza: los mecanismos de financiación de la guerra durante el reinado de Alfonso XI (1312-1350

    Directory of Open Access Journals (Sweden)

    Agrait, Nicolás

    2012-12-01

    Full Text Available To understand how it was possible for Alfonso XI to triumph militarily over his enemies, it is not enough to look at his courage, leadership and military strategies and tactics. One also has to study in depth the mechanisms he used to cover the high costs of his multiple campaigns and ordinary defense costs. In addition to the Crown’s regular fiscal resources and those taxes specifically related to warfare, Alfonso came to depend more and more on extraordinary levies, like monedas foreras, servicios, alcabalas, the temporary suspension of fiscal exemptions at the local level, the wealth of the Church, loans, and the sale of parts of the royal patrimony. These financial mechanisms opened up new sources of revenue to feed his military ambitions and truly constituted one of the most fundamental reasons for Alfonso’s success as a monarch and commander.

    Para entender cómo fue posible el triunfo militar de Alfonso XI sobre sus enemigos hay que mirar más allá de su valor, liderazgo y estrategias y tácticas bélicas, y estudiar a fondo los mecanismos que utilizó para sufragar los elevados costes de sus múltiples campañas y los gastos de defensa ordinarios. Además de utilizar los recursos fiscales de la Corona y los tributos tradicionales relacionados a la guerra, Alfonso dependió, cada vez más, de impuestos extraordinarios, como monedas foreras, servicios, alcabalas, la suspensión temporal de exenciones fiscales a nivel local, recursos monetarios eclesiásticos, empréstitos, y ventas de patrimonio real. Estos mecanismos financieros abrieron nuevas fuentes de ingreso para financiar sus ambiciones militares y realmente constituyeron una de las razones fundamentales del éxito de Alfonso como monarca y comandante militar.

  2. Cultura e política: José Vasconcelos e Alfonso Reyes no Brasil (1922-1938

    Directory of Open Access Journals (Sweden)

    Regina Aída Crespo

    2003-07-01

    Full Text Available De 1922 a 1938, as relações culturais entre o México e o Brasil conheceram um momento particularmente fecundo, devido em grande parte à atuação de dois intelectuais mexicanos: José Vasconcelos e Alfonso Reyes. A ausência de uma tradição de intercâmbio cultural entre o México e o Brasil fez do âmbito diplomático um espaço fundamental para a aproximação entre os dois países. Como representantes do governo mexicano - e transitando entre as fronteiras muitas vezes difusas da cultura e da política -, Vasconcelos, em 1922, e Reyes, de 1930 a 1938, estabeleceram uma ampla rede de contatos com intelectuais brasileiros e conseguiram fazer do México uma referência cultural e política importante no Brasil, durante o período.From 1922 to 1938, cultural relations between Mexico and Brazil had a particularly rich moment basically due to two Mexican intellectuals: José Vasconcelos and Alfonso Reyes. There was no tradition of cultural interchange between Mexico and Brazil; so the diplomatic sphere was transformed into a fundamental space for the approximation between these two countries. As representatives of the Mexican government - traveling between the frequently diffuse boundaries of culture and politics - Vasconcelos, in 1922, and Reyes, from 1930 to 1938, established a wide network of contacts with Brazilian intellectuals and managed to make Mexico an important cultural reference in Brazil, during that period.

  3. Limit of Salt in the Gulf Coast [saltlimitg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The data provides the approximate limit of Middle Jurassic salt from Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F....

  4. Preliminary Basin Analysis of Latest Miocene Conglomerate Near Bahía Kino, Coastal Sonora: A New Record of Crustal Deformation During Initial Opening of the Northern Gulf of California

    Science.gov (United States)

    Dorsey, R. J.; Peryam, T. C.; Bennett, S.; Oskin, M. E.; Iriondo, A.

    2008-12-01

    In coastal Sonora northwest of Bahía Kino, we have initiated a basin-analysis study of nonmarine conglomerate (Tcg) that overlies and is locally interbedded with the 6.4-Ma Tuff of Mesa Cuadrada (Tmc). Tcg conglomerate is deeply eroded and cut by a complex set of syn- to post-basinal, N- to NNE-striking normal faults and NW-striking dextral strike-slip faults. We carried out detailed mapping and field descriptions, measured stratigraphic sections, and collected paleocurrent and clast-count data in Tcg. Zircons from the newly discovered Seri tuff near the base of the section, 160 m below Tmc, were dated using U-Pb SHRIMP geochronology at Stanford University. We obtained a 206Pb/238U weighted mean age of 6.53+/-0.18 Ma (n=14; MSWD=1.3), which yields a sediment-accumulation rate of 0.8+/-0.2 mm/yr for lower Tcg. Tcg is dominated by debris-flow facies consisting of massive, poorly sorted, weakly bedded, matrix-rich, pebble, cobble, to small-boulder conglomerate. A subsidiary sheet-flood facies is somewhat better sorted, generally lacks boulders, and contains weak but pervasive horizontal stratification. Both facies of Tcg record deposition in an alluvial fan environment. Well sorted and stratified stream deposits are conspicuously lacking. Preserved sections of Tcg range up to 170 to 240 meters thick in the southern part of the study area, and increase to at least 470 meters in the north where the Punta Chueca fault, a large NW-directed low-angle normal fault, apparently produced more extension and subsidence than smaller faults in the south. Clasts in Tcg are dominated by middle Miocene andesite, the 12.6-Ma Tuff of San Felipe, minor amounts of Tmc, and variable amounts of older basement rocks including tonalite, granodiorite, quartzite, metavolcanic rock, and a megacrystic K-spar-bearing granite that we have not seen in the local bedrock. After correcting for bedding dips and vertical-axis clockwise rotations determined from paleomagnetic analysis, restored

  5. Un paso de América: Alfonso Reyes, Victoria Ocampo y el cosmopolitismo en la década de 1930 / Un paso de América: Alfonso Reyes, Victoria Ocampo and the Cosmopolitanism in the 1930’s

    Directory of Open Access Journals (Sweden)

    Gorica Majstorovic

    2014-12-01

    Full Text Available El artículo trata de las construcciones americanistas del cosmopolitismo (entendido en relación a la geopolítica imperial en los textos de Victoria Ocampo y Alfonso Reyes de los años treinta. Al analizar su relación con los movimientos de inmigración y la subsiguiente revalorización de la nación, el artículo postula que en Alfonso Reyes la mediación cosmopolita es «des-jerarquizada», ubicada casi siempre en una «periferia», a diferencia de Victoria Ocampo cuyas visiones cosmopolitas son mediadas desde un «centro» —ya sea París o Buenos Aires— y relacionadas con una jerarquía de valores estéticos y políticos.The article deals with Americanist constructions of cosmopolitanism (understood in relation to the imperial geopolitics in the texts of Victoria Ocampo and Alfonso Reyes in the 1930’s. Upon analyzing its relationship with immigration movements and the subsequent revaluation of the nation, the article suggests that in Alfonso Reyes cosmopolitan mediation is «dis-hierarchized», almost always located in a periphery, unlike Victoria Ocampo whose cosmopolitan visions are mediated from a «center» —either Paris or Buenos Aires— and related to a hierarchy of aesthetic and political values.

  6. Algunas precisiones y nuevos datos en torno a los Alfonso: una familia de canteros en el arzobispado de Toledo (1383-1431

    Directory of Open Access Journals (Sweden)

    Palomo Fernández, Gema

    2000-12-01

    Full Text Available The documents from the archives in the cathedral of Cuenca mention, among the masters working there since the first century, the names of two stonemasons: Ferrand and Juan, with the common surname «Alfonso». The latter will become «master of the construction of the church» in 1420, These two stonemasons are evidently members of the polemical family Alfonso. They were working at the same time at the Cathedral of Toledo, where they had been employed for a long time, as well as in other buildings under the orders of archbishop Pedro Tenorio. In this article, I will provide some unpublished data about this important and large clan which has produced so much confusion among the specialists.No disponible

  7. Martinez Arranz, Alfonso / Doyle, Natalie J. / Winand, Pascaline (eds.), New Europe, New World? The European Union, Europe and the Challenges of the 21 st Century,

    OpenAIRE

    Adrian IVAN

    2010-01-01

    New Europe, New World? The European Union, Europe, and the Challenges of the 21 st Century is a collective work that emerged from such an academic engagement generated by the Monash European and EU Center (at Monash University, Australia) in collaboration with the Austral-Asian Center for Italian Studies. The editors, Alfonso Martinez Arranz, Natalie J. Doyle and Pascaline Winand, succeeded in turning the conference debates into a coherent volume that will certainly contribute to the academic...

  8. Faults in the Gulf Coast [gcfaultsg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These mapped faults are modified from Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in Volume J, The Geology...

  9. Gulf War

    DEFF Research Database (Denmark)

    Dalgaard-Nielsen, Anja

    2003-01-01

    As it became a non‐permanent member of the UN Security Council in January 2003, Germany stepped up its opposition to war with Iraq. The stage was set for a repeat of Germany's uncomfortable position during the 1991 Gulf War. At that time, as most of Germany's allies rallied behind Washington......, Germany made only financial contributions, and hundreds of thousands of Germans took to the streets to protest against the war. Yet, since 1991, Germany had come a long way in its attitudes towards military force. From a policy of complete abstention from military deployments beyond NATO's area (so...

  10. Modeling the Gulf Stream System: How Far from Reality?

    Science.gov (United States)

    Choa, Yi; Gangopadhyay, Avijit; Bryan, Frank O.; Holland, William R.

    1996-01-01

    Analyses of a primitive equation ocean model simulation of the Atlantic Ocean circulation at 1/6 deg horizontal resolution are presented with a focus on the Gulf Stream region. Among many successful features of this simulation, this letter describes the Gulf Stream separation from the coast of North America near Cape Hatteras, meandering of the Gulf Stream between Cape Hatteras and the Grand Banks, and the vertical structure of temperature and velocity associated with the Gulf Stream. These results demonstrate significant improvement in modeling the Gulf Stream system using basin- to global scale ocean general circulation models. Possible reasons responsible for the realistic Gulf Stream simulation are discussed, contrasting the major differences between the present model configuration and those of previous eddy resolving studies.

  11. Alfonso IX de León y el iter de su corte (1188-1230

    Directory of Open Access Journals (Sweden)

    Gregoria CAVERO DOMÍNGUEZ

    2009-12-01

    Full Text Available Alfonso IX de León, a lo largo de su dilatado reinado, desarrolló la mayor parte de las actividades de la corte de forma itinerante, es decir en medio de sus largos y continuados desplazamientos, tal como reflejan las datas de los documentos de su cancillería. La ciudad de León, sede regia, no fue el epicentro de su corte, aunque en ella se desarrollaran las primeras cortes.La majeure partie des activités du roi de León Alphonse IX se déroulèrent, au cours de son long règne, de façon itinérante, c’est-à-dire au cours de ses longs déplacements, comme le réflètent les données documentaires de sa chancellerie. La ville de León, siège royal, ne fut pas l’épicentre de sa cour, mais accueillit pourtant les premières cortes.

  12. Alfonso Reyes en dos tiempos. Entre el arielismo y la doble experiencia literaria: "La venganza creadora" y "La cena"

    Directory of Open Access Journals (Sweden)

    Pablo Aparicio Durán

    2013-06-01

    Full Text Available Es sabido que Alfonso Reyes dejó una enorme impronta intelectual y literaria no sólo en la literatura de su país, Méjico, sino en toda la literatura hispanoamericana. Pero, aparte de las dimensiones de la huella dejada por el autor, lo realmente interesante es el terreno que pisa, y ese, para nosotros, es el terreno ideológico. Así, en el presente artículo ofrecemos una panorámica general sobre la significación cultural del autor mejicano, precisamente para tratar de delimitar que una cosa son las ideologías culturales explícitas y otra cosa es el inconsciente ideológico/literario implícito. En este sentido, se ha efectuado el análisis de dos cuentos del prolífico escritor de Monterrey (La venganza creadora y La cena en relación con otros dos de Edgar Allan Poe y Ernest Hemingway (Allá en Michigan y La casa Usher, respectivamente.

  13. Coastal fisheries in the Eastern Baltic Sea (Gulf of Finland and its basin from the 15 to the Early 20th centuries.

    Directory of Open Access Journals (Sweden)

    Julia Lajus

    Full Text Available The paper describes and analyzes original data, extracted from historical documents and scientific surveys, related to Russian fisheries in the southeastern part of the Gulf of Finland and its inflowing rivers during the 15- early 20(th centuries. The data allow tracing key trends in fisheries development and in the abundance of major commercial species. In particular, results showed that, over time, the main fishing areas moved from the middle part of rivers downstream towards and onto the coastal sea. Changes in fishing patterns were closely interrelated with changes in the abundance of exploited fish. Anadromous species, such as Atlantic sturgeon, Atlantic salmon, brown trout, whitefish, vimba bream, smelt, lamprey, and catadromous eel were the most important commercial fish in the area because they were abundant, had high commercial value and were easily available for fishing in rivers. Due to intensive exploitation and other human-induced factors, populations of most of these species had declined notably by the early 20(th century and have now lost commercial significance. The last sturgeon was caught in 1996, and today only smelt and lamprey support small commercial fisheries. According to historical sources, catches of freshwater species such as roach, ide, pike, perch, ruffe and burbot regularly occurred, in some areas exceeding half of the total catch, but they were not as important as migrating fish and no clear trends in abundance are apparent. Of documented marine catch, Baltic herring appeared in the 16(th century, but did not become commercially significant until the 19(th century. From then until now herring have been the dominant catch.

  14. Coastal fisheries in the Eastern Baltic Sea (Gulf of Finland) and its basin from the 15 to the Early 20th centuries.

    Science.gov (United States)

    Lajus, Julia; Kraikovski, Alexei; Lajus, Dmitry

    2013-01-01

    The paper describes and analyzes original data, extracted from historical documents and scientific surveys, related to Russian fisheries in the southeastern part of the Gulf of Finland and its inflowing rivers during the 15- early 20(th) centuries. The data allow tracing key trends in fisheries development and in the abundance of major commercial species. In particular, results showed that, over time, the main fishing areas moved from the middle part of rivers downstream towards and onto the coastal sea. Changes in fishing patterns were closely interrelated with changes in the abundance of exploited fish. Anadromous species, such as Atlantic sturgeon, Atlantic salmon, brown trout, whitefish, vimba bream, smelt, lamprey, and catadromous eel were the most important commercial fish in the area because they were abundant, had high commercial value and were easily available for fishing in rivers. Due to intensive exploitation and other human-induced factors, populations of most of these species had declined notably by the early 20(th) century and have now lost commercial significance. The last sturgeon was caught in 1996, and today only smelt and lamprey support small commercial fisheries. According to historical sources, catches of freshwater species such as roach, ide, pike, perch, ruffe and burbot regularly occurred, in some areas exceeding half of the total catch, but they were not as important as migrating fish and no clear trends in abundance are apparent. Of documented marine catch, Baltic herring appeared in the 16(th) century, but did not become commercially significant until the 19(th) century. From then until now herring have been the dominant catch.

  15. Basin Analysis of the Mississippi Interior Salt Basin and Petroleum System Modeling of the Jurassic Smackover Formation, Eastern Gulf Coastal Plain, Final Report and Topical Reports 5-8 on Smackover Petroleum system and Underdevelopment Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Ernest A.; Puckett, T. Markham; Parcell, William C.; Llinas, Juan Carlos; Kopaska-Merkel, David C.; Townsend, Roger N.

    2002-03-05

    The Smackover Formation, a major hydrocarbon-producing horizon in the Mississippi Interior Salt Basin (MISB), conformably overlies the Norphlet Formation and is conformably overlain by the Buckner Anhydrite Member of the Haynesville Formation. The Norphlet-Smackover contact can be either gradational or abrupt. The thickness and lithofacies distribution of the Smackover Formation were controlled by the configuration of incipient paleotopography. The Smackover Formation has been subdivided into three informal members, referred to as the lower, middle and upper members.

  16. Variations in the chemical and stable isotope composition of carbon and sulfur species during organic-rich sediment alteration: An experimental and theoretical study of hydrothermal activity at guaymas basin, gulf of california

    Science.gov (United States)

    Seewald, Jeffrey S.; Seyfried, W.E.; Shanks, Wayne C.

    1994-01-01

    Organic-rich diatomaceous ooze was reacted with seawater and a Na-Ca-K-Cl fluid of seawater chlorinity at 325-400??C, 400-500 bars, and fluid/sediment mass ratios of 1.56-2.35 to constrain factors regulating the abundance and stable isotope composition of C and S species during hydrothermal alteration of sediment from Guaymas Basin, Gulf of California. Alteration of inorganic and organic sedimentary components resulted in extensive exchange reactions, the release of abundant H2S, CO2, CH4, and Corganic, to solution, and recrystallization of the sediment to an assemblage containing albitic plagioclase, quartz, pyrrhotite, and calcite. The ??34Scdt values of dissolved H2S varied from -10.9 to +4.3??? during seawater-sediment interaction at 325 and 400??C and from -16.5 to -9.0??? during Na-Ca-K-Cl fluid-sediment interaction at 325 and 375??C. In the absence of seawater SO4, H2S is derived from both the transformation of pyrite to pyrrhotite and S released during the degradation of organic matter. In the presence of seawater SO4, reduction of SO4 contributes directly to H2S production. Sedimentary organic matter acts as the reducing agent during pyrite and SO4 reduction. Requisite acidity for the reduction of SO4 is provided by Mg fixation during early-stage sediment alteration and by albite and calcite formation in Mg-free solutions. Organically derived CH4 was characterized by ??13Cpdb values ranging between -20.8 and -23.1???, whereas ??13Cpdb values for dissolved Corganic ranged between -14.8 and -17.7%. Mass balance calculations indicate that ??13C values for organically derived CO2 were ??? - 14.8%. Residual solid sedimentary organic C showed small (??? 0.7???) depletions in 13C relative to the starting sediment. The experimental results are consistent with the isotopic and chemical composition of natural hydrothermal fluids and minerals at Guaymas Basin and permit us to better constrain sources and sinks for C and S species in subseafloor hydrothermal systems

  17. La poesía de Alfonso Álvarez Guerrero: arte mayor al servicio del Imperio

    Directory of Open Access Journals (Sweden)

    Xavier Tubau

    2012-06-01

    Full Text Available Alfonso Álvarez Guerrero (1502-1576, juriste tolédan qui exerça longtemps sa profession au royaume de Naples, publia en 1520, juste après la diffusion de la nouvelle de l’élection de Charles-Quint comme Roi des Romains, un volume contenant deux œuvres en vers, Las Doscientas del Castillo de la Fama (200 coplas en arte mayor et Las Cincuenta del Laberinto contra Fortuna (50 coplas reales. Dix plus tard, dans le contexte du couronnement impérial de Bologne, un autre volume parut, avec deux nouveaux poèmes: le Palacio de la Fama (154 coplas en arte mayor et l’Historia de las guerras de Italia (354 coplas en arte mayor. Le propos de cet article est de présenter une première analyse du contenu de ces œuvres poétiques. La première partie du travail replace ces œuvres dans le cadre de l’histoire littéraire de l’époque, en soulignant la survivance de la poétique de l’arte mayor – qui prend exemple sur l’œuvre de Juan de Mena – dans les premières décennies du XVIe siècle. La seconde partie tente d’expliquer les implications politiques de certaines idées formulées par l’auteur dans ses poèmes, à la lumière du jeu des diverses factions concurrentes à la cour du jeune empereur, au cours de la décennie de 1520.Alfonso Álvarez Guerrero (1502-1576, jurista toledano que desarrolló buena parte de su trayectoria profesional en el Reino de Nápoles, publicó en 1520, justo después de conocerse la elección de Carlos V como futuro Rey de Romanos, un volumen en el que se incluían dos obras en verso, Las Doscientas del Castillo de la Fama (200 coplas en arte mayor y Las Cincuenta del Laberinto contra Fortuna (50 coplas reales. Diez años más tarde, en el contexto de la coronación imperial en Bolonia, aparecía otro volumen con dos poemas más: el Palacio de la Fama (154 coplas en arte mayor y la Historia de las guerras de Italia (354 coplas en arte mayor. El propósito de este artículo es presentar una primera

  18. A propósito del desarrollo urbano del País Vasco durante el reinado de Alfonso X

    Directory of Open Access Journals (Sweden)

    González Mínguez, César

    1997-06-01

    Full Text Available One aspect of long lasting consequences in the policy of king Alfonso X the Wise is that concerning the urbanization and resetting of the territories of the Castilian Kingdom, which up to the middle of the 13th century had already achieved the territorial expansion that almost with no changes is going to be mantained till 1492. This work looks through the urbanization policy followed by the mentioned king in the Basque Country, particularly in the cases of Vitoria and Mondragon. At the same time, we want to underline some of the data which allow us to state that the growing phase in the Basque urban area went on till the earlier years of the 14th century.[fr] L'un des aspects qui, dans la politique du roi Alphonse X le Savant, a eu les conséquences les plus heureuses et les plus durables, est celui qui concerne le repeuplement et l'urbanisation du territoire appartenant à la Couronne de Castille. Déjà vers le milieu du XlIIème siècle celle-ci avait pris une tournure qui, avec peu de variations, se maintiendra jusqu'en 1492. En partant de cette perspective, il s'agit de passer en revue la politique de fondation de villes développée par ce même roi au Pays Basque, en particulier pour le cas de Mondragon et de Vitoria. Au même temps, nous voulons mettre en relief quelques données historiques permettant d'établir la durée de la période de croissance du milieu urbain basque jusqu'aux premières dates du XIVème siècle.

  19. La empresa informativa y el poder de informar, según la perspectiva de tres autores contemporáneos: Alfonso Nieto, Niklas Luhmann y Roberto Marafioti

    OpenAIRE

    Rodríguez Rowe, Verónica

    2015-01-01

    El origen de la tesis es el estudio de la visión de autores contemporáneos, de distinta nacionalidad y profesión, respecto a un tema siempre contingente: la empresa informativa y el poder de informar. Se exploraron las aportaciones del español Alfonso Nieto, el alemán Niklas Luhmann y el argentino Roberto Marafioti. Se evidenciaron distintas posiciones respecto al rol de los mass media. Así Luhmann1 precisa que constituyen una forma de comunicación que se emplaza en el mismo nivel de operaci...

  20. Comunicar para el cambio social: una comunicación ética y política. Entrevista con Alfonso Gumucio Dagron

    OpenAIRE

    Gabriel Jaime Pérez S.J.; Mónica Marion Cataño; Fanny Patricia Franco

    2009-01-01

    En este artículo, a partir de sus experiencias académicas y laborales, Alfonso Gumucio Dagron define el concepto comunicación para el cambio social como el planteamiento más reciente de las teorías de la dependencia y de los enfoques de la comunicación. Él sostiene que se centra en la sistematización de experiencias, porque facilita recuperar el conocimiento producido en el diálogo social, a partir de lecciones narradas y aprendidas por las comunidades. Así mismo, sostiene que la metodología ...

  1. Alfonso de Palencia. Ad Alfonsum de Velasco in funebrem Abulensis praesulis fabulosa narratio (ca. 1455: edición crítica del MS UCM BH 133

    Directory of Open Access Journals (Sweden)

    Durán Barceló, Javier

    2012-01-01

    Full Text Available Aunque ya estaba catalogado desde 1745 y de nuevo en 1800, los modernos estudiosos no tuvieron noticia de la existencia de este manuscrito del siglo XV de Alfonso de Palencia hasta que Bartolomé José Gallardo lo describió. Gallardo describe el manuscrito Ad Alfonsum de Velasco in funebrem Abulensis praesulis cuando éste se encontraba a modo de préstamo en la Real Academia de la Historia, en Madrid, a mediados del siglo XIX. En aquella época la RAH procuraba la publicación de las obras de Alfonso de Palencia y seguramente a aquellos esfuerzos se debe que se conserve actualmente en la RAH una copia moderna de este manuscrito medieval, el cual fue devuelto a su propietaria. La primera edición del texto la hicieron en 1982 Brian Tate y Rafael Alemany Ferrer basándose para ello en la copia decimonónica. Pues, dado que Gallardo había dado una información confusa acerca de la localización del manuscrito medieval, los modernos editores no pudieron localizarlo. Este trabajo resuelve finalmente el problema de la localización del manuscrito original, conservado en la Universidad Complutense de Madrid. Gracias a este hallazgo mi edición del texto se basa directamente en el original medieval sobre el que intento dilucidar algunas lecturas difícilesAlthough it had been catalogued in 1745 and again in 1800, it was not until Bartolomé José Gallardo reported the existence of this 15th century manuscript of Alfonso de Palencia when scholars became aware of its existence. Gallardo described the manuscript Ad Alfonsum de Velasco in funebrem Abulensis praesulis when it was borrowed by the Royal Academy of History, in Madrid, in mid 19th century. At that time the Academy was involved in the edition of the works of Alfonso de Palencia and for this reason a hand written copy of the medieval manuscript remained in the Academy, while the original was returned to its owner. Based on this 19th century copy, Brian Tate and Rafael Alemany Ferrer published

  2. Last millennium sedimentation in the Gulf of Cariaco (NE Venezuela): Evidence for morphological changes of gulf entrance and possible relations with large earthquakes

    Science.gov (United States)

    Aguilar, Iliana; Beck, Christian; Audemard, Franck; Develle, Anne-Lise; Boussafir, Mohammed; Campos, Corina; Crouzet, Christian

    2016-01-01

    The Cariaco Basin and the Gulf of Cariaco in Venezuela are two major basins along the seismogenic El Pilar right lateral fault, among which the Cariaco Basin is a pull-apart. Both basins are sites of anoxia and organic-rich deposits. To examine whether the sediments in the Gulf of Cariaco have recorded traces of historical or prehistorical earthquakes, we extracted and analyzed twelve 1 m-long gravity cores, sampling the last millennium sedimentation. We focused on analyzing the sediment sources with different techniques (particle size analysis, XRF, loss on ignition tests, magnetic properties, Rock-Eval pyrolysis, 14C dating). The results confirm that major upwelling occurs at the western gulf entrance and makes deep water flowing from the Cariaco Basin into the Gulf of Cariaco. These flows carry an organic-rich suspended load. Furthermore, we found evidence of a particular, widespread fine-grained siliciclastic deposit (named SiCL3) within the gulf, whose age suggests that it likely formed during the large 1853 AD earthquake that stroke the Cumaná city. We suggest that the earthquake-induced large submarine landslides that modified the topography of the gulf's entrance, which in turn promoted upwelling and open marine water flows from the Cariaco Basin. The layer SiCL3 would be the sediment load remobilized during this chain of events.

  3. Vejamen de Alfonso de Batres para la Academia de 1638 (Manuscrito inédito. Estudio y edición crítica

    Directory of Open Access Journals (Sweden)

    Julio, Teresa

    2013-06-01

    Full Text Available During February 1638 the Fiestas de Carnestolendas were celebrated at the Buen Retiro Palace, Madrid. Among the programmed activities, a literary gathering was held, open to numerous poets and courtiers. From this gathering three vejamenes have been preserved: those of Alfonso de Batres, Antonio Coello and Francisco de Rojas Zorrilla. In this paper we analyze and annotate the vejamen that Batres read before His Majesties in the Royal Salon of the Retiro Palace on February 11, 1638.Durante el mes de febrero de 1638 se celebraron en el palacio del Buen Retiro las fiestas de Carnestolendas. Entre las actividades programadas, se realizó una academia literaria en la que participaron poetas y cortesanos. De ella se conservan tres vejámenes: el de Alfonso de Batres, el de Antonio Coello y el de Francisco de Rojas Zorrilla. En el presente artículo se analiza y edita críticamente el vejamen que Batres defendió ante sus majestades en el Salón Real del Retiro el 11 de febrero de 1638.

  4. El redescubrimiento de la otredad: nuevas perspectivas sobre el descubrimiento de la conquista en Caminarás con el sol de Alfonso Mateo Sagasta

    Directory of Open Access Journals (Sweden)

    Francesca Crippa

    2013-07-01

    Full Text Available RESUMEN: Alfonso Mateo-Sagasta es uno de los autores más representativos del panorama literario español actual. Su última novela, Caminarás con el sol, aborda uno de los episodios más controvertidos de la historia española e hispanoamericana a través del punto de vista de un hombre, Gonzalo Guerrero, que decidió abandonar sus tradiciones para convertirse en guerrero maya. La finalidad de este trabajo es analizar los principales recursos temáticos y estilísticos de la obra de Mateo-Sagasta en relación con la específica época histórica de ambientación de la novela. ABSTRACT: Alfonso Mateo-Sagasta is one of the most popular authors of the present Spanish literary panorama. His last novel, Caminarás con el sol, approaches one of the most debated episodes of the Spanish and Latin American history by adopting the point of view of a man, Gonzalo Guerrero, who decided to renounce to his own culture in order to become a Mayan warrior. The aim of this article is to analyze the main thematic and stylistic features of Mateo-Sagasta’s novel and its approach to the specific historical period.

  5. Anécdotas castellanas en escritura hebraica. Apuntes paremiológicos conservados en las anotaciones hebreas de Alfonso de Zamora (Ms. Leiden Or. 645

    Directory of Open Access Journals (Sweden)

    Alonso Fontela, Carlos

    2011-12-01

    Full Text Available Problems of translation and interpretation are addressed in this presentation of Alfonso de Zamora’s Hebrew and Hebrew “Aljamiado” Spanish notes (ca. 1530 from Leiden University Library Ms. Or. 645 (ol. Warner 65 containing anecdotes, sayings and short tales. Additional notes dealing with a manuscript copy of the Targum to the Prophets comissioned by the University of Salamanca are also discussed.

    Este artículo estudia algunas notas manuscritas de Alfonso de Zamora en hebreo y en aljamía hebraico-castellana datadas hacia 1530, y procedentes del ms. Or. 645 (ol. Warner 65 de la Biblioteca de la Universidad de Leiden. Dichas notas contienen anécdotas, refranes y «cuentecillos», tales como las anécdotas «de fray Palomo», «de un portugués», y «de lo que dijo el gallego». Otras anotaciones de Zamora tratan de un trabajo de copia del Targum a los Profetas por encargo de la Universidad de Salamanca.

  6. Prólogo arameo y anotaciones hebreas de Alfonso de Zamora para una copia manuscrita del Targum a los Profetas encargada por la Universidad de Salamanca

    Directory of Open Access Journals (Sweden)

    Fontela, Carlos Alonso

    2009-12-01

    Full Text Available University Library Ms. Or. 645, f. 110r (ol. Warner 65 F contains, besides a draft for an Aramaic prologue to the work on Targum written by Alonso de Zamora ca. 1532, additional notes written by himself dealing with the comission he received to copying Targumic texts. The present article improves the edition of the Aramaic prologue, previously published by Neubauer (1895, offering a Spanish translation and the edition of the marginal notes, that contain a draft of the prayers (תפלותופיהספדים for the partial colophons of the books of Ezekiel, Hosea and Joel’s Targums. These pa - tial colophons in the Leiden Ms. coincide with the clean drafts by Zamora preserved in an autograph manuscript, Salamanca University Library Ms. M-3 (Est.-1, Cajón I-Núm. 2. An explanation concerning additional annotations (the incipit of Isaiah 57, that spoiled the folio, and led it to its being re-used by Alonso de Zamora as a draft.

    El ms. Or. 645, f.º 110r (ol. Warner 65 F de la Leiden University Library, además del borrador de un prólogo arameo a la obra de Targum escrito por Alfonso de Zamora hacia el año 1532 por encargo de la Universidad de Salamanca, contiene otras anotaciones del mismo autor que aquí se publican por primera vez y que también formaban parte del mismo encargo de copia de textos targúmicos. En el presente artículo, además de mejorar el texto arameo del prólogo ya publicado por Neubauer en 1895, se ofrece su traducción española por primera vez. Asimismo, se publica y traduce una anotación marginal que consiste en un borrador de las jaculatorias o doxologías (תפלותופיהספדים para los colofones parciales de los libros del Targum de Ezequiel, Oseas y Joel. Estos colofones parciales del ms. de Leiden coinciden con los pasados a limpio que se conservan en el manuscrito autógrafo de Alfonso de Zamora ms. M-3 (Est.-1, Cajón I-Núm. 2 de la Biblioteca Universitaria de Salamanca. Se

  7. Muerte, religiosidad e ideología: el significado del ajuar en los sepulcros de Alfonso X y Sancho IV de Castilla

    Directory of Open Access Journals (Sweden)

    Parra Aguilar, Leonor

    2016-06-01

    Full Text Available The burials of monarchs of the kingdom of Castile show us how the kings expected to leave signs of their power even in death. Through careful study and comparison of funerary objects of Alfonso X and Sancho IV of Castile, we will raise a hypothesis, which confirms the existence of the same ideological model in both monarchs. To achieve this, will pay attention to the elements of power with that they demand to entomb themselves that are intended to be symbols of royal ideology. It will be seen how in the funerary areas of the powerful, the monarchical aspirations tend to increase his fortitude as a weapon and as political propaganda, always relying on religiosity for argue their power.Los enterramientos de los monarcas del reino de Castilla nos muestran como los reyes pretendían dejar señales de su poder aún en la muerte. A través del estudio detallado y la comparación de los ajuares de Alfonso X y Sancho IV de Castilla, plantearemos una hipótesis que advierte la existencia de un mismo modelo ideológico en ambos monarcas. Para llegar a ello, se prestará atención a los elementos de poder con los que se entierran, que pretenden ser símbolos de la ideología regia. Se verá cómo en los ámbitos funerarios de los poderosos, las pretensiones monárquicas tienden a multiplicar su fortaleza como arma y como propaganda política, siempre apoyándose en la religiosidad para argumentar su poder.

  8. Beyond the Gulf Metropolises

    DEFF Research Database (Denmark)

    Wippel, Steffen

    2013-01-01

    The extended studies on urbanisation in the Gulf region that came up in the early 2000s concentrated on the main centres with their worldwide-admired mega-projects and branding strategies. Only rather recently did a more general interest arise in the second-tier range of Gulf cities, which also s...

  9. AEROBIC DENITRIFICATION: IMPLICATIONS FOR THE MOM RIVER BASIN

    Science.gov (United States)

    Each year about 1.6 million metric tons of nitrogen, mostly from agriculture, is discharged from the lower Mississippi/Atchafalaya River Basin into the Gulf of Mexico, and each spring this excess nitrogen fuels the formation of a huge hypoxic zone in the Gulf. In the Mississippi...

  10. Rings dominate western Gulf

    Science.gov (United States)

    Vidal L., Francisco V.; Vidal L., Victor M. V.; Molero, José María Pérez

    Surface and deep circulation of the central and western Gulf of Mexico is controlled by interactions of rings of water pinched from the gulf's Loop Current. The discovery was made by Mexican oceanographers who are preparing a full-color, 8-volume oceanographic atlas of the gulf.Anticyclonic warm-core rings pinch off the Loop Current at a rate of about one to two per year, the scientists of the Grupo de Estudios Oceanográficos of the Instituto de Investigaciones Eléctricas (GEO-IIE) found. The rings migrate west until they collide with the continental shelf break of the western gulf, almost always between 22° and 23°N latitude. On their westward travel they transfer angular momentum and vorticity to the surrounding water, generating cyclonic circulations and vortex pairs that completely dominate the entire surface and deep circulation of the central and western gulf.

  11. Rift offsets, Gulf of Suez, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Patton, T.L.; Nelson, R.A.

    1988-01-01

    Structure and stratigraphic mapping in the northern half of the Gulf of Suex (GOS) documents two en echelon, rift-parallel (Clysmic trend) rift segments. The segments are right stepping and share a zone of overlap, which extends southward from the southern border of the Wadi Araba structure on the western shore of the gulf to the north end of the Abu Durba block on the east side of the gulf. The spatial relationship of the two segments defines the central GOS rift offset, and the structural depression linking the segments in the area of overlap forms a rift-offset zone. Another potential rift offset, though less well constrained, also with a north-south trend may be present south of Gebel Zeit. This rift and the central GOS rift offset provide a model for the opening of the GOS in which north-south rift-offset zones link Clysmic-trending rift segments, imparting a regional zig-zag pattern to the initial rift configuration. Recognition of offset zones and their associated fault fabrics is essential for effective exploration of rift basins. For example, the alignment of producing fields and elongation directions of individual fields in the central GOS offset are anomalous relative to those of other producing trends in the Gulf.

  12. Rift offsets, Gulf of Suez, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Patton, T.L.; Nelson, R.A.

    1988-02-01

    Structure and stratigraphic mapping in the northern half of the Gulf of Suez (GOS) documents two en echelon, rift-parallel (Clysmic trend) rift segments. The segments are right stepping and share a zone of overlap, which extends southward from the southern border of the Wadi Araba structure on the western shore of the gulf to the north end of the Abu Durba block on the east side of the gulf. The spatial relationship of the two segments defines the central GOS rift offset, and the structural depression linking the segments in the area of overlap forms a rift-offset zone. Another potential rift offset, though less well constrained, also with a north-south trend may be present south of Gebel Zeit. This rift and the central GOS rift offset provide a model for the opening of the GOS in which north-south rift-offset zones link Clysmic-trending rift segments, imparting a regional zig-zag pattern to the initial rift configuration. Recognition of offset zones and their associated fault fabrics is essential for effective exploration of rift basins. For example, the alignment of producing fields and elongation directions of individual fields in the central GOS offset are anomalous relative to those of other producing trends in the Gulf.

  13. Water Masses and Nutrient Sources to the Gulf of Maine

    Science.gov (United States)

    Townsend, David W.; Pettigrew, Neal R.; Thomas, Maura A.; Neary, Mark G.; McGillicuddy, Dennis J.; O’Donnell, James

    2016-01-01

    The Gulf of Maine, a semi-enclosed basin on the continental shelf of the northwest Atlantic Ocean, is fed by surface and deep water flows from outside the Gulf: Scotian Shelf Water from the Nova Scotian shelf that enters the Gulf at the surface, and Slope Water that enters at depth and along the bottom through the Northeast Channel. There are two types of Slope Water, Labrador Slope Water (LSW) and Warm Slope Water (WSW); it is these deep water masses that are the major source of dissolved inorganic nutrients to the Gulf. It has been known for some time that the volume inflow of Slope Waters of either type that enters the Gulf of Maine is variable, that it co-varies with the magnitude of inflowing Scotian Shelf Water, and that periods of greater inflows of Scotian Shelf Water have become more frequent in recent years, accompanied by reduced Slope Water inflows. We present here analyses of a ten-year record of data collected by moored sensors in Jordan Basin, in the interior Gulf of Maine, and in the Northeast Channel, along with recent and historical hydrographic and nutrient data, that help reveal the nature of Scotian Shelf Water and Slope Water inflows. Proportional inflows of nutrient-rich Slope Waters and nutrient-poor Scotian Shelf Waters alternate episodically with one another on time scales of months to several years, creating a variable nutrient field upon which the biological productivities of the Gulf of Maine and Georges Bank depend. Unlike decades past, the inflows of Slope Waters of either type do not appear to be correlated with the North Atlantic Oscillation, which had been shown earlier to influence the relative proportions of the two Slope Waters, WSW and LSW, that enter the Gulf. We suggest that of greater importance in recent years are more frequent, episodic influxes of colder, fresher, less dense, and low-nutrient Scotian Shelf Water into the Gulf of Maine, and concomitant reductions in the inflow of deep, nutrient-rich Slope Waters. We also

  14. Tiered collaborative strategies for reducing hypoxia and restoring the Gulf of Mexico

    Science.gov (United States)

    The Gulf of Mexico is more than just a water body south of the United States. It is an international marine ecosystem, the ninth largest water body in the world (USEPA 2007), and it receives drainage from the Mississippi River Basin (MRB), the third largest drainage basin in the world. The combine...

  15. Vides de Simón de Rojas Clemente (1777-1827 en el herbario del Real Colegio Alfonso XII de San Lorenzo de El Escorial (Madrid, España

    Directory of Open Access Journals (Sweden)

    Perea, Domingo

    1997-12-01

    Full Text Available In the present paper, the discovery of grape-vine mounted sheets from the Simón de Rojas Clemente herbarium, which were found in the Herbarium of the Real Colegio Alfonso XH in San Lorenzo de El Escorial, is reported. This material completes the collection of Clemente's vines which makes up one of the historical collections deposited in the MA herbarium.Damos a conocer unos pliegos de vides procedentes del herbario de Simón de Rojas Clemente que han aparecido en el Gabinete de Ciencias Naturales del Real Colegio Alfonso XII de San Lorenzo de El Escorial. Estos materiales completan la colección de vides de Clemente que constituye uno de los herbarios históricos depositados en MA.

  16. Gulf Shrimp System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gulf of Mexico Shrimp Landings - This data set contains catch (landed catch) and effort for fishing trips made by the larger vessels that fish near and offshore for...

  17. Gulf stream separation dynamics

    Science.gov (United States)

    Schoonover, Joseph

    Climate models currently struggle with the more traditional, coarse ( O(100 km) ) representation of the ocean. In these coarse ocean simulations, western boundary currents are notoriously difficult to model accurately. The modeled Gulf Stream is typically seen exhibiting a mean pathway that is north of observations, and is linked to a warm sea-surface temperature bias in the Mid-Atlantic Bight. Although increased resolution ( O(10 km) ) improves the modeled Gulf Stream position, there is no clean recipe for obtaining the proper pathway. The 70 year history of literature on the Gulf Stream separation suggests that we have not reached a resolution on the dynamics that control the current's pathway just south of the Mid-Atlantic Bight. Without a concrete knowledge on the separation dynamics, we cannot provide a clean recipe for accurately modeling the Gulf Stream at increased resolutions. Further, any reliable parameterization that yields a realistic Gulf Stream path must express the proper physics of separation. The goal of this dissertation is to determine what controls the Gulf Stream separation. To do so, we examine the results of a model intercomparison study and a set of numerical regional terraforming experiments. It is argued that the separation is governed by local dynamics that are most sensitive to the steepening of the continental shelf, consistent with the topographic wave arrest hypothesis of Stern (1998). A linear extension of Stern's theory is provided, which illustrates that wave arrest is possible for a continuously stratified fluid.

  18. 2014 Gulf of Mexico Hypoxia Forecast

    Science.gov (United States)

    Scavia, Donald; Evans, Mary Anne; Obenour, Dan

    2014-01-01

    The Gulf of Mexico annual summer hypoxia forecasts are based on average May total nitrogen loads from the Mississippi River basin for that year. The load estimate, recently released by USGS, is 4,761 metric tons per day. Based on that estimate, we predict the area of this summer’s hypoxic zone to be 14,000 square kilometers (95% credible interval, 8,000 to 20,000) – an “average year”. Our forecast hypoxic volume is 50 km3 (95% credible interval, 20 to 77).

  19. 2013 Gulf of Mexico Hypoxia Forecast

    Science.gov (United States)

    Scavia, Donald; Evans, Mary Anne; Obenour, Dan

    2013-01-01

    The Gulf of Mexico annual summer hypoxia forecasts are based on average May total nitrogen loads from the Mississippi River basin for that year. The load estimate, recently released by USGS, is 7,316 metric tons per day. Based on that estimate, we predict the area of this summer’s hypoxic zone to be 18,900 square kilometers (95% credible interval, 13,400 to 24,200), the 7th largest reported and about the size of New Jersey. Our forecast hypoxic volume is 74.5 km3 (95% credible interval, 51.5 to 97.0), also the 7th largest on record.

  20. Comunicar para el cambio social: una comunicación ética y política. Entrevista con Alfonso Gumucio Dagron

    Directory of Open Access Journals (Sweden)

    Gabriel Jaime Pérez S.J.

    2009-01-01

    Full Text Available En este artículo, a partir de sus experiencias académicas y laborales, Alfonso Gumucio Dagron define el concepto comunicación para el cambio social como el planteamiento más reciente de las teorías de la dependencia y de los enfoques de la comunicación. Él sostiene que se centra en la sistematización de experiencias, porque facilita recuperar el conocimiento producido en el diálogo social, a partir de lecciones narradas y aprendidas por las comunidades. Así mismo, sostiene que la metodología más adecuada para dinamizar experiencias de comunicación para el cambio social es la investigación acción-participativa (iap, porque permite investigar y acompañar procesos desde el conocimiento académico y profesional en dinámicas de participación, diálogo y construcción colectiva.

  1. Gulf Island National Wildlife Refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document provides a brief history and describes physical features of the Gulf Island National Wildlife Refuges. The Gulf Island National Wildlife Refuges...

  2. Geologic evolution of the continental margin of the Gulf of Tehuantepec in Southwestern Mexico

    Science.gov (United States)

    Sanchez-Barreda, L. A.

    Through the use of surface geology, paleomagnetic data, gravity surveys, and continuous seismic reflection profiles, the evolution of the Gulf of Tehuantepec is detailed as a progression from an open ocean basin to a more restricted basinal setting. Paleomagnetic data from the Mexican states of Chiapas and Oaxaca suggest an equatorial location for the Yucatan block during the Permian. The Gulf of Tehuantepec and its associated coastal plain is divided into three regions based on the character and distribution of the gravity anomalies. The differences in these regions suggest a northerly increase in tectonic activity in the basin and the coastal plain. A possible extension of the Polochic fault into the Gulf of Tehuantepec is indicated by coincidence of a linear trend of gravity anomalies in the southern coastal plain with the westernmost end of the fault.

  3. A Dynamic Gulf

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Pan-Beibu Gulf region will be the growth engine for China-ASEAN cooperation After running a travel company in Cambodia for more than a decade,Mo Chunrong decided to return to Nanning, capital of Guangxi Zhuang Autonomous Region,

  4. Alfonso López Pumarejo y la última Corte Suprema de Justicia de la hegemonía conservadora, 1934-1935

    Directory of Open Access Journals (Sweden)

    Mario Alberto Cajas Sarria

    2013-01-01

    Full Text Available Este artículo analiza las relaciones entre el Ejecutivo y la Corte Suprema de Justicia de Colombia durante el primer año de gobierno del presidente liberal Alfonso López Pumarejo, entre 1934 y 1935, cuando este lidió con un tribunal integrado por una mayoría de magistrados pertenecientes al Partido Conservador, que era percibido como el último bastión de la hegemonía conservadora. Este trabajo pone en evidencia el comportamiento estratégico de una Corte Suprema dominada por magistrados de origen conservador, que parecía intentar una relación institucional de colaboración con el nuevo gobierno hacia el año 1934. Reconstruye el juicio de constitucionalidad a la reforma tributaria impuesta por decreto de estado de sitio del Ejecutivo liberal que la Corte declaró inexequible en 1935, cuya decisión generó que la corporación fuera percibida como un órgano que actuaba movido por intereses partidistas. Por último, ofrece un análisis en conjunto sobre el rol político del tribunal en esta coyuntura del régimen político colombiano. Este análisis busca contribuir a una mejor comprensión del control constitucional colombiano y del rol que jugó la Corte Suprema de Justicia como juez constitucional –y por tanto, actor del régimen político–, en una perspectiva histórica, en este caso en el contexto de la transición de la hegemonía conservadora a la Segunda República Liberal que se consolidó con el gobierno de la Revolución en Marcha.

  5. Tra corti e campi di battaglia: Alfonso d’Avalos, Luigi Tansillo e le affinità elettive tra petrarchisti napoletani e spagnoli

    Directory of Open Access Journals (Sweden)

    Tobia R. Toscano

    2012-06-01

    Full Text Available Tra tutte le capitali che entrarono a far parte del grande impero di Carlo V, Napoli appare, fin dal soggiorno di Garcilaso, il luogo ideale per l’esercizio della poesia lirica: qui era già molto sviluppato quel processo di compenetrazione tra armas y letras che costituisce la divisa di una nuova pleiade di petrarchisti, che, accanto alla occupazione prevalente del servizio militare, avevano sviluppato già sul declinare del sec. XV un interesse e una pratica costanti della poesia, anticipando nella prassi il modello del perfetto cortegiano, assunto poi a modello dalle élites spagnole. Figure di grande rilievo in questo processo di modellizzazione possono essere considerati Alfonso d’Avalos, marchese del Vasto, e Luigi Tansillo, i cui manoscritti di rime per il III Duca di Sessa ebbero grande diffusione in Spagna, incrociandosi con l'esperienza lirica di Gutierre de Cetina, che sulla scorta di Tansillo introdurrà nella poesia spagnola la forma metrica del madrigale, non trattata né da Garcilaso né da Boscàn.Parmi toutes les capitales qui firent partie du grand Empire de Charles-Quint, Naples semble, à partir du séjour de Garcilaso, le lieu idéal pour l’exercice de la poésie lyrique. Le mariage des armes et des lettres (armas y letras y était déjà très avancé et était devenu la devise d’une nouvelle pléiade de pétrarquistes. Leur intérêt pour la poésie leur avait fait développer dès la fin du XVe siècle, en marge de leur occupation principale, le service militaire, une constante pratique de la poésie, anticipant le modèle du parfait courtisan, que les élites espagnoles allaient imiter. Dans ce processus de modélisation, une place particulière revient à Alfonso d’Ávalos, marquis del Vasto, et à Luigi Tansillo, dont les manuscrits de poésies pour le IIIe duc de Sessa connurent une importante diffusion en Espagne, où ils croisèrent l’expérience lyrique de Gutierre de Cetina. Celui-ci, à la suite de

  6. Muerte y espacio artístico en el hombre colonizado: análisis de la novela corta "la piel" de Alfonso Hernández Catá.

    OpenAIRE

    Michelle María, Álvarez Amargós

    2012-01-01

    El espacio artístico y la muerte se constituyeron en grandes obsesiones que acompañaron los textos narrativos de Alfonso Hernández Catá. Las relaciones que se establecen entre estos dos elementos en la novela corta “La piel”, perteneciente a la colección Los frutos ácidos, resultan el objetivo del presente trabajo, el cual se realizará a partir de los presupuestos del método de análisis de contenido. Esta novela corta está basada en los prejuicios de la clase media y en el hombre que ha sido ...

  7. Long-Period Ground Motion in the Arabian Gulf from Earthquakes in the Zagros Mountains Thrust Belt

    Science.gov (United States)

    Pitarka, Arben; Al-Amri, Abdullah; Pasyanos, Michael E.; Rodgers, Arthur J.; Mellors, Robert J.

    2015-10-01

    The Arabian Gulf is adjacent to the Zagros Mountains, one of the most seismically active regions in the world. We observe that broadband seismic records of Zagros earthquakes recorded on the Arabian side of the Gulf display long-duration surface waves. While shorter periods (10 km) of the Gulf basin, the long-period energy is enhanced and transmitted efficiently. Consequently, large earthquakes in the Zagros could result in amplified ground motions at long periods (2-10 s) relative to average behavior. Such ground motions are of concern for large engineered structures, such as tall buildings and long bridges with resonant periods in the same period range. Here we present results of investigations of the characteristics of ground motions recorded on the western shore of the Gulf from selected earthquakes in the Zagros Mountains region. Exceptionally, long-duration seismic waves, as compared with standard models, are shown to occur with periods of 2-10 s. This may be due to waveguide effects in the deep sedimentary basin structure of the Arabian Platform. In addition to analyzing recorded ground motion we performed 3D wave propagation simulations using a finite difference method and experimental velocity models of the Gulf, with different shallow sedimentary layers structures. The simulation results confirm our hypothesis that long-period waves with extremely long duration and relatively large amplitudes are caused by the geometry of the basin sedimentary layers and, to some extent, by shallow earthquake depths. Combined effects of basin edge geometry with sharp velocity contrasts and shallow sources (<10 km) on the eastern side of the Arabian Gulf can cause large long-period ground motion on the western side of the Gulf. In contrast, the short-period content of ground motion (<2 s) at long distances is relatively weak. This is mainly due to wave propagation scattering and attenuation in the shallow sedimentary layers of the Gulf basin.

  8. Gulf operators resuming production

    International Nuclear Information System (INIS)

    This paper reports that Gulf of Mexico operators last week were gradually restoring production at installations struck by Hurricane Andrew. The Minerals Management Service continued receiving reports of more damage. By the end of the day Sept. 8, MMS had received reports of damage to 83 pipeline segments and 193 platforms and satellite installations. Damage reports listed 112 installations with structural damage, 13 platforms toppled and five leaning, and 30 satellite platforms toppled and 33 leaning. But despite the extent of damage the storm inflicted on oil and gas installations in the gulf, it pales in comparison to the misery and suffering the storm caused in Florida and Louisiana, an oil company official said

  9. Alfonso X el reino de Granada y los Banū Ašqīlūla. Estrategias políticas de disolución durante la segunda mitad del siglo XIII

    Directory of Open Access Journals (Sweden)

    García Fitz, Francisco

    1997-06-01

    Full Text Available The political leaders of the Castilian and Leonese Kingdom often took advantage of the problems in Al-Andalus to their own benefit. The Cristian kings exploited the internal differences of Peninsular Muslims and supported the rebellions against muslim political leaders in order to weaken them and to obtain territorial and economic advantages. During the second half of the thirteenth century, Alfonso X applied this political strategy and supported the rebellion carried out by the Banū Ašqīlūla against the kingdom of Granada.[fr] Les dirigeants politiques du royaume de "Castilla et León" bénéficièrent souvent des problèmes de "al-Andalus". Les souverains chrétiens exploitèrent les dissidences internes de l'Islam de la Péninsule et appuyèrent les rébellions contre les leaders politiques musulmans afin de les affaiblir et d'obtenir des profits territoriaux et économiques. Pendant la deuxième moitié du XlIIème siècle. Alfonso X usa de cette "stratégie politique" en encourageant la révolte des Banū Ašqīlūla tournée contre la stabilité de Granade.

  10. Evolution and seismic expression of Mesozoic and Cenozoic shelf margins, Gulf of Mexico and vicinity

    Energy Technology Data Exchange (ETDEWEB)

    Buffler, R.T.

    1983-03-01

    Mapping and classification of modern and ancient shelf margins provide a basis for a concise post-rifting history of the Gulf of Mexico basin. Many hydrocarbon occurrences in the basin can be related to styles of shelf margins and their associated slope with implications for frontier exploration in deep-water facies. Seven basic types of shelf margins have been recognized and are discussed.

  11. Site characterization plan: Gulf Coast salt domes

    International Nuclear Information System (INIS)

    The National Waste Terminal Storage (NWTS) program of the US Department of Energy (DOE) is responsible for developing technology and providing facilities for safe, environmentally acceptable, permanent disposal of high-level nuclear waste. The Office of Nuclear Waste Isolation has been intensively investigating Gulf Coast Salt Dome Basin salt domes and bedded salt in Texas and Utah since 1978. In the Gulf Coast, the application of screening criteria in the region phase led to selection of eight domes for further study in the location phase. Further screening in the area phase identified four domes for more intensive study in the location phase: Oakwood Dome, Texas; Vacherie Dome, Louisiana; and Richton Dome and Cypress Creek Dome, Mississippi. For each dome, this Site Characterization Plan identifies specific hydrologic, geologic, tectonic, geochemical, and environmental key issues that are related to the DOE/NWTS screening criteria or affect the feasibility of constructing an exploratory shaft. The Site Characterization Plan outlines studies need to: (1) resolve issues sufficiently to allow one or more salt domes to be selected and compared to bedded salt sites in order to determine a prime salt site for an exploratory shaft; (2) conduct issue-related studies to provide a higher level of confidence that the preferred salt dome site is viable for construction of an exploratory shaft; and (3) provide a vehicle for state input to issues. Extensive references, 7 figures, 20 tables

  12. Status of Gulf Coast salt dome characterization

    International Nuclear Information System (INIS)

    Screening and characterization for a potential nuclear waste repository have progressed through the area phase in these Gulf Coast Salt Basins. The domes studied during the area phase are described briefly. The area characterization studies are outlined, and the resulting reports are listed. Geologic and environmental studies resulted in elimination of four domes from further consideration. The remaining domes were judged acceptable and were classified as to their favorability to license. Site characterization planning for location phase activities deals primarily with technical, environmental, and socioeconomic issues of concern to the states and/or to the Office of Nuclear Waste Isolation (ONWI), Department of Energy (DOE). These issues are listed and discussed. 16 references, 9 figures

  13. Thermocline regulated seasonal evolution of surface chlorophyll in the Gulf of Aden.

    Science.gov (United States)

    Yao, Fengchao; Hoteit, Ibrahim

    2015-01-01

    The Gulf of Aden, although subject to seasonally reversing monsoonal winds, has been previously reported as an oligotrophic basin during summer, with elevated chlorophyll concentrations only occurring during winter due to convective mixing. However, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) ocean color data reveal that the Gulf of Aden also exhibits a prominent summer chlorophyll bloom and sustains elevated chlorophyll concentrations throughout the fall, and is a biophysical province distinct from the adjacent Arabian Sea. Climatological hydrographic data suggest that the thermocline, hence the nutricline, in the entire gulf is markedly shoaled by the southwest monsoon during summer and fall. Under this condition, cyclonic eddies in the gulf can effectively pump deep nutrients to the surface layer and lead to the chlorophyll bloom in late summer, and, after the transition to the northeast monsoon in fall, coastal upwelling driven by the northeasterly winds produces a pronounced increase in surface chlorophyll concentrations along the Somali coast.

  14. Thermocline Regulated Seasonal Evolution of Surface Chlorophyll in the Gulf of Aden

    KAUST Repository

    Hoteit, Ibrahim

    2015-04-01

    The Gulf of Aden, although subject to seasonally reversing monsoonal winds, has been previously reported as an oligotrophic basin during summer, with elevated chlorophyll concentrations only occurring during winter due to convective mixing. However, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) ocean color data reveal that the Gulf of Aden also exhibits a prominent summer chlorophyll bloom and sustains elevated chlorophyll concentrations throughout the fall, and is a biophysical province distinct from the adjacent Arabian Sea. Climatological hydrographic data suggest that the thermocline, hence the nutricline, in the entire gulf is markedly shoaled by the southwest monsoon during summer and fall. Under this condition, cyclonic eddies in the gulf can effectively pump deep nutrients to the surface layer and lead to the chlorophyll bloom in late summer, and, after the transition to the northeast monsoon in fall, coastal upwelling driven by the northeasterly winds produces a pronounced increase in surface chlorophyll concentrations along the Somali coast.

  15. Exploring Linkages Between Gulf of Mexico Sea Surface Conditions and North American Hydroclimate during the Holocene

    Science.gov (United States)

    Richey, J. N.; Thirumalai, K.; Quinn, T. M.; Poore, R. Z.

    2015-12-01

    The Gulf of Mexico is part of the Atlantic Warm Pool, a feature that drives oceanic moisture flux to the surrounding continent. It is connected to the North Atlantic Ocean via the loop current, which transports salt and heat from the Caribbean and Gulf of Mexico poleward via the Gulf Stream. As such, variations in Gulf of Mexico sea surface temperature (SST) and salinity (SSS) are linked to changes in North Atlantic Ocean circulation and North American hydroclimate. Although SST and SSS variability in the Gulf of Mexico are well understood on inter-annual and glacial-interglacial timescales, little is known about centennial scale variability in these sea surface parameters through the Holocene. We present here the first continuous multi-decadal resolution time series of SST and SSS spanning the entire Holocene from the Gulf of Mexico. This proxy reconstruction is based on paired measurements of Mg/Ca and δ18O in the planktic foraminifer, Globigerinoides ruber (white variety) in the Garrison Basin. Using these data, in combination with additional Gulf of Mexico SST and SSS records from the late Holocene, we explore linkages between North American precipitation patterns and ocean circulation on centennial timescales.

  16. Influence of resonance on tide and storm surge in the Gulf of Thailand

    Science.gov (United States)

    Tomkratoke, Saifhon; Sirisup, Sirod; Udomchoke, Veerasak; Kanasut, Jirawat

    2015-10-01

    A numerical simulation is used to determine the effective resonance period, quality factor Q and linear friction coefficient and mechanism of tide and storm surge in the Gulf of Thailand. The results indicated that the resonance response is triggered by the forced wave with the period of 20.25 hours. The Q factor and linear friction coefficient are approximately 3.15 and 2.76×10-5 ms-1, respectively. The gulf is regarded as a moderately dissipative system, which may yield small amplification for the oscillating forced wave. The resonance structure of the basin can play an important role in spatial distribution and amplification of tidal waves in the Gulf of Thailand and nearby area. Distance from the effective resonance period and the corresponding Q factor can be employed in characterizing of tidal amplification in the gulf. The study found that phase difference in the incoming tidal waves can induce the distortion of a nodal band to the normal mode analysis results. The resonance in the north-south direction is the principal mechanism to control tidal waves, specifically for the upper part of the gulf (the Gulf of Thailand). However, significant effect of resonance in the west-east direction on the amplification of tidal waves near the southern part of the gulf (Vietnam, Malaysia and Singapore coast) may be pronounced. From the reproduced historic storm surge and hypothetical results, the spatial distribution of storm surge elevation and the response ratio are in good agreement with the resonance mode and Q factor of the basin. Individually, the contribution of resonance factor to induce severe storm surge (positive surge) tends to be insignificant. Conversely, the interaction process between the disturbance system and the propagating surge wave in the gulf can induce large positive surge near the landfall location significantly.

  17. WATER TEMPERATURE, SALINITY, and HYDROSTATIC PRESSURE collected from R/V Point Sur in Entrance to the Gulf of California from 2013-04-19 to 2013-05-02 (NCEI Accession 0131072)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrographic data were collected in Pescadero Basin (at the entrance to the Gulf of California) and subsequently along the West Coast of Baja California and...

  18. Clay Mineral Distribution Patterns of Tertiary Continental Oil-bearing Basins in China

    Institute of Scientific and Technical Information of China (English)

    Zhao Xingyuan

    1996-01-01

    @@ Induction This paper studies the clay mineral distribution patterns of Tertiary continental oil-bearing basins in China. More than 9 000 shale samples from Paleogene (E) to Neogene (N) Series distributed in Bohai Gulf, Subei, Jianghan,Nanxiang, Zhoukou, Sanshui, Beibu Bay, East China Sea,Hetao, Juiquan, Qaidam and Tarim basins, and so on.

  19. Reconnaissance of the chemical quality of surface waters of the Sabine River Basin, Texas and Louisiana

    Science.gov (United States)

    Hughes, Leon S.; Leifeste, D.K.

    1965-01-01

    The Sabine River basin has an abundant supply .of surface water of excellent quality. The basin area of 9,700 square miles receives an average of about 48 inches of rainfall per year, of which about 13 inches flows to the Gulf of Mexico.

  20. Elementos sociohistóricos intervinientes en la construcción de los estadios Alfonso López y El Campín para los primeros Juegos Bolivarianos: Bogotá, 1938

    Directory of Open Access Journals (Sweden)

    Andrés Felipe Hernández Acosta

    2013-08-01

    Full Text Available La introducción de los deportes en las sociedades que entran en procesos de modernización es un fenómeno complejo, en el que intervienen muchos factores sociales, históricos y culturales. La necesidad de investigar el deporte científicamente viene tomando fuerza en Colombia en los años recientes. Este texto aspira a contribuir en esa dirección, tomando como objeto dos hitos arquitectónicos de construcción simultánea, que fueron importantes, no solo para nuestro desarrollo deportivo, sino para el rediseño urbanístico de la capital: el Estadio Nemesio Camacho, “El Campín” y el Estadio Alfonso López, de la Universidad Nacional de Colombia, en el año de 1938.

  1. Gulf of Mexico Hypoxia dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — Gulf of Mexico cruise, nearshore and CTD data collected by the USEPA during 2002 - 2008 This dataset is associated with the following publications: Pauer , J., T....

  2. Bibliography, geophysical data locations, and well core listings for the Mississippi Interior Salt Basin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    To date, comprehensive basin analysis and petroleum system modeling studies have not been performed on any of the basins in the northeastern Gulf of Mexico. Of these basins, the Mississippi Interior Salt Basin has been selected for study because it is the most petroliferous basin in the northeastern Gulf of Mexico, small- and medium-size companies are drilling the majority of the exploration wells. These companies do not have the resources to perform basin analysis or petroleum system modeling research studies nor do they have the resources to undertake elaborate information searches through the volumes of publicly available data at the universities, geological surveys, and regulatory agencies in the region. The Advanced Geologic Basin Analysis Program of the US Department of Energy provides an avenue for studying and evaluating sedimentary basins. This program is designed to improve the efficiency of the discovery of the nation`s remaining undiscovered oil resources by providing improved access to information available in the public domain and by increasing the amount of public information on domestic basins. This report provides the information obtained from Year 1 of this study of the Mississippi Interior Salt Basin. The work during Year 1 focused on inventorying the data files and records of the major information repositories in the northeastern Gulf of Mexico and making these inventories easily accessible in an electronic format.

  3. Quantitative basin evaluation, a tool for reducing exploration risks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Over the last decade, the evaluation of the petroleum potential of sedimentary basins has shifted from a qualitative to a quantitative approach. This new perspective has led to the elaboration of basin simulators and a new discipline emerged: the basin modeling which is nowadays massively used by the oil industry. This methodology is an integration platform including geology, geochemistry and physics. Combined with uncertainty assessments, it is a powerful tool for reducing exploration risks. In this respect, IFP dedicates one of its IFP Sessions to 'Quantitative Basin Evaluation, a Tool for Reducing Exploration Risks'. This session was held on 18 June, 2001. The purpose of this workshop is to review the most modern advances used by professionals in the oil industry to improve the rate of hydrocarbon discovery and to lower exploration costs in frontier areas. IFP Sessions are conferences held for decision-makers and technical leaders to promote exchanges among involved parties: oil and gas companies, petroleum services and supply industries, engineering firms and research centers. Program: quantitative basin evaluation: the Berkine basin and its results; application of 2-D and 3-D basin modelling in the Gulf of Mexico; 2-D modelling in Brazilian sedimentary basins: lessons from recent case histories; quantitative modelling in the North Sea: towards a more confident assessment of the critical risks (*); uncertainties evaluation in petroleum system modelling (*); prediction of hydrocarbon type in the deep-water, Gulf of Mexico (*); constraining source and charge risk in deep-water areas - the Gulf of Mexico and offshore Angola (*); an overview of basin modelling and geochemistry activities in PDO; quantitative basin evaluation: how does it affect decision in exploration (*); panel discussion: evolution of the modelling tools. Abstracts are available only for 5 presentations (marked with (*)). (J.S.)

  4. Geological evaluation of Gulf Coast salt domes: overall assessment of the Gulf Interior Region

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-10-01

    The three major phases in site characterization and selection are regional studies, area studies, and location studies. This report characterizes regional geologic aspects of the Gulf Coast salt dome basins. It includes general information from published sources on the regional geology; the tectonic, domal, and hydrologic stability; and a brief description the salt domes to be investigated. After a screening exercise, eight domes were chosen for further characterization: Keechi, Oakwood, and Palestine Domes in Texas; Vacherie and Rayburn's domes in North Louisiana; and Cypress Creek and Richton domes in Mississippi. A general description of each, maps of the location, property ownership, and surface geology, and a geologic cross section were presented for each dome.

  5. The influence of seasonal sea ice on the physics of the coastal waters - Gulf of Finland

    OpenAIRE

    Merkouriadi, Ioanna

    2014-01-01

    The Gulf of Finland is located in the seasonal sea ice zone (SSIZ), were sea ice forms in the wintertime and melts in late spring. This seasonality entitles this sea as a key area regarding the impact of climatic changes. When the basin of interest is located at the climatological edge of the SSIZ, there is also high inter-annual variability in the ice conditions. The aim of this study was to examine the influence of the sea ice on the physics of the coastal waters in the Gulf of Finland...

  6. Distribution and ecology of deep-water benthic foraminifera in the Gulf of Mexico

    Science.gov (United States)

    Poag, C.W.

    1984-01-01

    Bathyal and abyssal foraminifera in the Gulf of Mexico are distributed among thirteen generic predominance facies. Five predominance facies nearly encircle the Gulf basin along the slope and rise; a sixth predominance facies blankets the Sigsbee Plain, and a seventh is restricted to the Mississippi Fan. The remaining eight predominance facies have more restricted distributions. The areal patterns of these predominance facies can be related chiefly to water mass and substrate characteristics; modifications are brought about by calcite dissolution, upwelling, and sill depth. Analysis of ancient generic predominance facies is useful in predicting relative paleobathymetry and other paleoenvironmental properties. ?? 1984.

  7. Erosional processes and paleo-environmental changes in the Western Gulf of Lions (SW France) during the Messinian Salinity Crisis

    OpenAIRE

    Lofi, Johanna; Gorini, Christian; Berne, Serge; Clauzon, Georges; Dos Reis, A.tadeu; Ryan, William; Steckler, Michael

    2005-01-01

    Current interpretation of the Messinian Salinity Crisis (MSC) involves partial "clesiccation" of the Mediterranean Sea coupled with the deposition of thick evaporites in the deep basins. New sets of seismic reflection profiles in the western part of the Gulf of Lions confirm the basinward extension of the Messinian erosion and enable the mapping of distinctive seismic markers indicating the Messinian Erosional Surface (or Messinian unconformity), the basin-margin detrital deposits, and the de...

  8. Extensional hard linkages, eastern Gulf of Suez, Egypt

    Science.gov (United States)

    McClay, Ken; Khalil, Samir

    1998-06-01

    The Araba Abu Durba area on the eastern margin of the Gulf of Suez exhibits two superb outcrop examples of extensional hard linkages in a rift basin. Here, three large, domino-style, basement-cored, northeast-dipping fault blocks are formed by a series of major northwest-trending normal faults. These are offset by two north-northeast trending sinistral oblique-slip transfer faults that terminate in horsetail normal fault splays. The transfer faults do not extend across the entire rift basin. Detailed mapping and structural analysis show that they developed by breakage of initial low-strain relay ramps along reactivated north-northeast trending basement fabrics between overlapping northwest-trending normal fault segments. Paleostrain analysis of fault-slip indicators shows that both the normal and the sinistral oblique-slip transfer faults were formed synchronously in response to northeast-southwest extension, perpendicular to the main northwest rift trend.

  9. Convective upwelling in the mantle beneath the Gulf of California.

    Science.gov (United States)

    Wang, Yun; Forsyth, Donald W; Savage, Brian

    2009-11-26

    In the past six million years, Baja California has rifted obliquely apart from North America, opening up the Gulf of California. Between transform faults, seafloor spreading and rifting is well established in several basins. Other than hotspot-dominated Iceland, the Gulf of California is the only part of the world's seafloor-spreading system that has been surrounded by enough seismometers to provide horizontal resolution of upper-mantle structure at a scale of 100 kilometres over a distance great enough to include several spreading segments. Such resolution is needed to address the long-standing debate about the relative importance of dynamic and passive upwelling in the shallow mantle beneath spreading centres. Here we use Rayleigh-wave tomography to image the shear velocity in the upper 200 kilometres or so of the mantle. Low shear velocities similar to those beneath the East Pacific Rise oceanic spreading centre underlie the entire length of the Gulf, but there are three concentrated locations of anomalously low velocities spaced about 250 kilometres apart. These anomalies are 40 to 90 kilometres beneath the surface, at which depths petrological studies indicate that extensive melting of passively upwelling mantle should begin. We interpret these seismic velocity anomalies as indicating that partial melting triggers dynamic upwelling driven by either the buoyancy of retained melt or by the reduced density of depleted mantle. PMID:19940924

  10. Gulf Petro Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Fathi Boukadi

    2011-02-05

    In this report, technologies for petroleum production and exploration enhancement in deepwater and mature fields are developed through basic and applied research by: (1) Designing new fluids to efficiently drill deepwater wells that can not be cost-effectively drilled with current technologies. The new fluids will be heavy liquid foams that have low-density at shallow dept to avoid formation breakdown and high density at drilling depth to control formation pressure. The goal of this project is to provide industry with formulations of new fluids for reducing casing programs and thus well construction cost in deepwater development. (2) Studying the effects of flue gas/CO{sub 2} huff n puff on incremental oil recovery in Louisiana oilfields bearing light oil. An artificial neural network (ANN) model will be developed and used to map recovery efficiencies for candidate reservoirs in Louisiana. (3) Arriving at a quantitative understanding for the three-dimensional controlled-source electromagnetic (CSEM) geophysical response of typical Gulf of Mexico hydrocarbon reservoirs. We will seek to make available tools for the qualitative, rapid interpretation of marine CSEM signatures, and tools for efficient, three-dimensional subsurface conductivity modeling.

  11. Temperature of the Gulf Stream

    Science.gov (United States)

    2002-01-01

    The Gulf Stream is one of the strong ocean currents that carries warm water from the sunny tropics to higher latitudes. The current stretches from the Gulf of Mexico up the East Coast of the United States, departs from North America south of the Chesapeake Bay, and heads across the Atlantic to the British Isles. The water within the Gulf Stream moves at the stately pace of 4 miles per hour. Even though the current cools as the water travels thousands of miles, it remains strong enough to moderate the Northern European climate. The image above was derived from the infrared measurements of the Moderate-resolution Imaging Spectroradiometer (MODIS) on a nearly cloud-free day over the east coast of the United States. The coldest waters are shown as purple, with blue, green, yellow, and red representing progressively warmer water. Temperatures range from about 7 to 22 degrees Celsius. The core of the Gulf Stream is very apparent as the warmest water, dark red. It departs from the coast at Cape Hatteras, North Carolina. The cool, shelf water from the north entrains the warmer outflows from the Chesapeake and Delaware Bays. The north wall of the Gulf Stream reveals very complex structure associated with frontal instabilities that lead to exchanges between the Gulf Stream and inshore waters. Several clockwise-rotating warm core eddies are evident north of the core of the Gulf Stream, which enhance the exchange of heat and water between the coastal and deep ocean. Cold core eddies, which rotate counter clockwise, are seen south of the Gulf Stream. The one closest to Cape Hatteras is entraining very warm Gulf Stream waters on its northwest circumference. Near the coast, shallower waters have warmed due to solar heating, while the deeper waters offshore are markedly cooler (dark blue). MODIS made this observation on May 8, 2000, at 11:45 a.m. EDT. For more information, see the MODIS-Ocean web page. The sea surface temperature image was created at the University of Miami using

  12. Analysis of Temporal Variability of Measured and Modeled Vertical Distributions of Salinity and Temperature in the Gulf of Finland during 10-Year Period

    OpenAIRE

    PASSENKO Jelena; LESSIN GENNADI; Raudsepp, Urmas; Maljutenko, Ilja; Neumann, Thomas; Laanemets, Jaan

    2010-01-01

    The Gulf of Finland is the sub-basin of the Baltic Sea seriously affected by eutrophication. General Estuarine Transport Model (GETM) was used for modeling hydrophysical fields of the Gulf during the period from 1997 to 2005. The results of the hydrodynamic modeling are important input for ecosystem modeling, in which salinity and temperature variations play the most important role. An accurately simulated salinity field is to some extent a proof that the transport of passive bio-chemical tra...

  13. Coastal change and hypoxia in the northern Gulf of Mexico: Part I

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The Committee on Environment and Natural Resources (CENR has identified the input of nutrient-rich water from the Mississippi/Atchafalaya River Basin (MARB as the prime cause of hypoxia in the northern Gulf of Mexico and the prime means for its control. A Watershed Nutrient Task Force was formed to solve the hypoxia problem by managing the MARB catchment. However, the hypoxic zone is also experiencing massive physical, hydrological, chemical and biological changes associated with an immense river-switching and delta-building event that occurs here about once a millennium. Coastal change induced hypoxia in the northern Gulf of Mexico prior to European settlement. It is recommended that for further understanding and control of Gulf hypoxia the Watershed Nutrient Task Force adopt a truly holistic environmental approach which includes the full effects of this highly dynamic coastal area.

  14. The Sediment Sequence in the Southern Gulf of California — Distribution, Thickness, Sedimentlogical and Rock Magnetic Properties

    Science.gov (United States)

    Fucugauchi, J. U.; Perez-Cruz, L.

    2008-05-01

    The Gulf of California is a young tectonic ocean basin formed by sea-floor spreading and transform faulting along the Pacific-North America plate boundary. The Gulf of California is an elongated narrow basin oriented almost N- S, and bordered by the Baja California peninsula and mainland Mexico. To the north, it limits with the basins and transform fault of the San Andreas, and in the south with the East Pacific Rise and transform faults of the Rivera and Cocos plates. Here we focus on the sediment sequence in the southern sector at the mouth of the Gulf and the margin and central basins, which constitute a rich archive of the Gulf tectonic opening, plate boundary reorganizations and the paleoclimatic and paleoenvironmental evolution. Marine magnetic anomalies can be traced to approximately 3.6 Ma ago in the area of the mouth of the Gulf. There are relatively few studies of magnetic mineralogy, rock magnetism, magnetostratigraphy and paleomagnetism in these marine sediments. Here we present initial results of a study on the distribution and relative thickness of the sediment sequences in the mouth of the Gulf from geophysical surveys. Relative distribution and thicknes of sediments correlate with the bathymetry and location with respect to spreading center, transform faults and margins of the peninsula and mainland Mexico. Main sediment sources are silicic rocks from the Comondu Formation in the Baja California peninsula and the intrusive and volcanic rocks in Jalisco and Nayarit, including the Puerto Vallarta batholith. Pluvial terrigenous, fine-grained eolian and biogenic sediments are present in the sediment cores with less frequent turbiditic and tephra deposits. Core analyses of rock magnetic properties and mineralogy at few locations are summarized and discussed in terms of sediment sources, transport and deposition processes, diagenesis, paleoceanographic and paleoclimatic evolution during the Late Quaternary.

  15. La dialéctica texto-imagen. A propósito de la representación del judío en las “Cantigas de Santa María” de Alfonso X

    Directory of Open Access Journals (Sweden)

    Rodríguez Barral, Paulino

    2007-06-01

    Full Text Available The treatment of the image of Jews in the Cantigas by Alfonso X fluctuates between their total condemnation and the perspective of salvation. The condemnation of Judaism embodies some classic topics of medieval anti-Semitism such as alliance with the devil, infanticide, ritual murder, or sacrilegious desecration. This negative vision is tempered in some cantigas in which their jewish protagonists embrace the Christian faith as a result of Virgin Mary's intervention.

    This ambiguity may be a reflection of the monarch's attitude towards Judaism. On the one hand his reign is marked by prejudice both in certain proceedings and in the regulations of the Partidas, but on the other some Jews cooperate actively with the king's cultural and and scientific undertakings and even hold important public positions.



    El tratamiento de la imagen del judío en las Cantigas de Alfonso X oscila entre la condena sin paliativos y la perspectiva de la salvación. La primera toma cuerpo en algunos de los motivos clásicos del antisemitismo medieval como la alianza con el diablo, el infanticidio, el crimen ritual, o la profanación sacrílega. Una visión extremadamente negativa que se matiza en aquéllas cantigas en las que sus protagonistas, a instancias de la intervención mariana, acaban abrazando la fe cristiana.

    Probablemente haya que ver en todo ello un reflejo de la ambigüedad que, en relación al judaísmo, caracteriza el

  16. La financiación de las empresas mediterráneas de Alfonso el Magnánimo. Bailía General, Subsidios de Cortes y Crédito Institucional en Valencia (1419-1455

    Directory of Open Access Journals (Sweden)

    Mira Jódar, Antonio José

    2003-12-01

    Full Text Available This article studies the role of the General Bailía of Valencia—the office for the management of the royal domain resources of the kingdom of Valencia- in the political and military projects of Alfonso V the Magnanimous in the Mediterranean. In this way its also analysed the role of the Parliament, a class representation of the kingdom, and the city of Valencia, main urban centre The incomes from the royal domain, the donations from the Parliaments as a representative assemblies, and the loans provided by the city of Valencia contributed in a decisive way to the guarantee of the economic viability of Alfonso Vs military expansion. It is right that the main instruments that the king had to apply his aggressive policy was, on the one hand, the centralized and complex organization around the General Treasure of the Crown of Aragon and, later on, to the Treasure of the Kingdom of Naples; on the other hand, to the solid banking infrastructure built around the Mediterranean. Therefore, both of them were based on the confidence and guaranties offered by the powerful ordinary and non ordinary tax structures of the kingdom, and the solid financial support given by the institutions of the kingdom.

    En este trabajo se pretende determinar la funciones respectivas que la bailía general de Valencia, como oficina administradora de los recursos patrimoniales de la corona, las Cortes, en su calidad de representación estamental del reino, y la ciudad de Valencia, el principal centro urbano del país, desempeñaron en la financiación de los ambiciosos proyectos político-militares de Alfonso V en el Mediterráneo. De hecho, las rentas derivadas del Real Patrimonio, los donativos proporcionados por las asambleas representativas y los préstamos facilitados por el municipio contribuyeron decisivamente a garantizar la viabilidad económica de las empresas bélicas del Magnánimo. Es cierto que los principales instrumentos con los que contaba el monarca

  17. Facing Today's Exploration Challenges in the Gulf of Mexico

    Science.gov (United States)

    Detomo, R.

    2005-05-01

    The Gulf of Mexico represents one of the most intensively explored basins in the world, and yet it still delivers significant new material oil and gas discoveries every year. Because of it high productivity, geologic complexity, competitive acreage access and large profitability margins, the Gulf of Mexico presents many industry-leading challenges to Exploration today. For major companies exploring for oil and gas in the Gulf of Mexico today, their challenge is to "safely, responsibly and profitably find and produce reduced accumulations in increasingly hostile settings." The GoM serves as the sportsman's playground for a significant population located in and around its waters, and therefore, operating safely and responsibly are unassailable moral and operational standards by which we sustain future development, and maintain our license to operate. With that as a backdrop, today's challenges are driven by the nature of where the business is looking for new reserves in this extremely mature basin. These "Opportunities" encompass the following: 1) large, under-explored, sub-salt areas, characterized by poor seismic imaging, uncertain geologic regimes and potentially dangerous overpressures, 2) deep true-vertical-depth opportunities in older rocks that challenge our understanding of reservoir quality prediction and hydrocarbon systems, and are at the edge of today's drilling technologies, 3) access to sensitive areas including the eastern GoM-Florida shelf, coastal areas and international borders, 4) challenging "small accumulation" discoveries that cannot support expensive appraisal or development options, are remote to infrastructure or inefficiently produce the reservoir, and finally 5) new play development, which is challenged by long maturation cycles, small acreage blocks, intense international competition, and rapid lease rolls. This talk will consider what Shell and the Oil & Gas Industry does today to succeed in this arena, and specifically will show examples

  18. The Role of Rift Obliquity in Formation of the Gulf of California

    Science.gov (United States)

    Bennett, Scott Edmund Kelsey

    The Gulf of California illustrates how highly oblique rift geometries, where transform faults are kinematically linked to large-offset normal faults in adjacent pull-apart basins, enhance the ability of continental lithosphere to rupture and, ultimately, hasten the formation of new oceanic basins. The Gulf of California rift has accommodated oblique divergence of the Pacific and North America tectonic plates in northwestern Mexico since Miocene time. Due to its infancy, the rifted margins of the Gulf of California preserve a rare onshore record of early continental break-up processes from which to investigate the role of rift obliquity in strain localization. Using new high-precision paleomagnetic vectors from tectonically stable sites in north-central Baja California, I compile a paleomagnetic transect of Miocene ignimbrites across northern Baja California and Sonora that reveals the timing and distribution of dextral shear associated with inception of this oblique rift. I integrate detailed geologic mapping, basin analysis, and geochronology of pre-rift and syn-rift volcanic units to determine the timing of fault activity on Isla Tiburon, a proximal onshore exposure of the rifted North America margin, adjacent to the axis of the Gulf of California. The onset of strike-slip faulting on Isla Tiburon, ca. 8 - 7 Ma, was synchronous with the onset of transform faulting along a significant length of the nascent plate boundary within the rift. This tectonic transition coincides with a clockwise azimuthal shift in Pacific-North America relative motion that increased rift obliquity. I constrain the earliest marine conditions on southwest Isla Tiburon to ca. 6.4 - 6.0 Ma, coincident with a regional latest Miocene marine incursion in the northern proto-Gulf of California. This event likely flooded a narrow, incipient topographic depression along a ˜650 km-long portion of the latest Miocene plate boundary and corresponds in time and space with formation of a newly

  19. La infanta Doña María, monja de Sijena, y su política castellana durante la minoría de Alfonso XI (1312-1325

    Directory of Open Access Journals (Sweden)

    García Fernández, Manuel

    1998-12-01

    Full Text Available The Infanta Doña María, the eldest daughter of James II of Aragon, was a decisive and influential personality in Castilian politics during Alfonso XI's minority years (1312-1325. Married to the Infante Don Pedro, uncle and tutor of the king of Castile, she would perform her duties consistently following the political guidelines of her husband until his death in 1319. Thenceforward, her relationships with the circles of royal power were not in good terms. Questions such as the government and administration of her feudal patrimonies, inherited from Don Pedro, and the birth of her daughter Blanca, as well as her education and residence in either Aragon or Castille, were all tackled by the Infanta from Aragon, from the Monastery of Sijena opposing the longing tor power of both the Infante Don Felipe and García Lasso de la Vega, and even of king Alfonso XI himself. This essay aims at the analysis of these relationships from a Castilian perspective, making use of the excellent documentation kept in the ACA and edited from old.[fr] L'infante Marie, fille aînée du roi Jacques II d'Aragon, fut un personnage décisif et influent de la société politique castillane pendant la minorité d'Alphonse XI (1312-1325. Mariée à l'infant Pierre, oncle et tuteur du roi de Castille, elle se conforma aux directives poliques de son époux jusqu'à la mort de ce dernier en 1319. À partir de cette date, ses relations avec les milieux proches du pouvoir royal ne furent pas bonnes. L'administration de ses domaines seigneuriaux, hérités de l'infant Pierre, la naissance et l'éducation de sa fille Blanche ainsi que sa résidence aragonaise ou castillane constituèrent autant d'affaires que l'infante dut défendre de l'Aragon, du Monastère de Sijena, contre les convoitises de l'infant Philippe, de Garcia Lasso de la Vega et du roi Alphonse XI lui-même. Cette étude a pour but l'analyse de toutes ces relations du point de vue castillan, en prenant comme base l

  20. Gramíneas uruguayas de D. José Arechavaleta (1838-1912, en el Real Colegio Alfonso XII de San Lorenzo de El Escorial (Madrid, España

    Directory of Open Access Journals (Sweden)

    Carrasco, María A.

    2001-12-01

    Full Text Available The Royal Monastery of El Escorial was built in the xvi century by king Felipe U. In the part intended to be a college and seminary, the Real Colegio Alfonso XII was established in 1885. In this place, the treasures that had been accumulated for fíve hundred years, that carne from acquisitions, collections and donations, are stored. In this paper we present a small collection, of undeniable historical valué. It contains 186 Gramineae that were sent as a present to María Cristina, the Regent Queen of Spain, by the President of Uruguay on the occasion of the World Exhibition of Barcelona in 1888. The plants are part of the herbarium of the Flora Uruguaya of José Arechavaleta y Balparda [Santurce (España, 1838-Montevideo (Uruguay, 1912]. Some of the plants are annotated by Arechavaleta as new species, and some belong from the loc. clas. All this material is identified by Arechavaleta and J. Hackel.El Real Monasterio de El Escorial fue fundado en el siglo XVI por el rey Felipe n. En la parte dedicada a colegio-seminario se estableció en 1885 el Real Colegio Alfonso XII, donde están depositados todos los fondos que se han ido acumulando a lo largo de quinientos años, procedentes de adquisiciones, recolecciones y donaciones. En este trabajo presentamos una colección, pequeña pero de indudable valor histórico, de 186 Gramineae que fueron enviadas por el presidente del Uruguay a la reina regente de España con motivo de la Exposición Universal de Barcelona celebrada en 1888. Estos materiales son parte del herbario de la Flora Uruguaya de D. José Arechavaleta y Balparda [Santurce (España, 1838-Montevideo (Uruguay, 1912]. Algunas plantas están anotadas por Arechavaleta como especies nuevas -unas cuantas proceden de la localidad clásica- y todas ellas están identificadas por Arechavaleta o J. Hackel.

  1. 1400 yr multiproxy record of climate variability from the northern Gulf of Mexico

    Science.gov (United States)

    Richey, J.N.; Poore, R.Z.; Flower, B.P.; Quinn, T.M.

    2007-01-01

    A continuous decadal-scale resolution record of climate variability over the past 1400 yr in the northern Gulf of Mexico was constructed from a box core recovered in the Pigmy Basin, northern Gulf of Mexico. Proxies include paired analyses of Mg/Ca and δ18O in the white variety of the planktic foraminifer Globigerinoides ruber and relative abundance variations of G. sacculifer in the foraminifer assemblages. Two multi-decadal intervals of sustained high Mg/Ca indicate that Gulf of Mexico sea surface temperatures (SSTs) were as warm or warmer than near-modern conditions between 1000 and 1400 yr B.P. Foraminiferal Mg/Ca during the coolest interval of the Little Ice Age (ca. 250 yr B.P.) indicate that SST was 2–2.5 °C below modern SST. Four minima in the Mg/Ca record between 900 and 250 yr B.P. correspond with the Maunder, Spörer, Wolf, and Oort sunspot minima, suggesting a link between changes in solar insolation and SST variability in the Gulf of Mexico. An abrupt shift recorded in both δ18Ocalcite and relative abundance of G. sacculifer occurred ca. 600 yr B.P. The shift in the Pigmy Basin record corresponds with a shift in the sea-salt-sodium (ssNa) record from the Greenland Ice Sheet Project 2 ice core, linking changes in high-latitude atmospheric circulation with the subtropical Atlantic Ocean.

  2. Maps showing distribution of the Middle Cretaceous unconformity in the eastern Gulf of Mexico

    Science.gov (United States)

    Massingill, L.M.; Wells, R.H.

    1987-01-01

    Several theories on the origin of the Gulf of Mexico basin have been introduced by various researchers (Beloussov, 1970; Freeland and Dietz, 1971; Malfait and Dinkelman, 1972; Wood and Walper, 1974; Pilger, 1978; Buffler and others, 1980; Dickinson and Coney, 1980; Gose and others, 1980; Schmidt-Effing, 1980; Walper, 1980; Schlager and others, 1984). Although no final agreement has been reached, one prominent geologic feature is generally recognized. The early evolution of the basin ended with a major middle Cretaceous event resulting in a Gulf-wide unconformity referred to as the middle Cretaceous unconformity (MCU). This event represents a major shift from Early Cretaceous shallow-water bank sedimentation to Late Cretaceous deeper water carbonates (Worzel and others, 1973; Mitchum, 1978).

  3. Seismic stratigraphy and geologic history of Jurassic rocks, northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, L.M.; Buffler, R.T. [Univ. of Texas, Austin, TX (United States)

    1997-01-01

    A grid of two-dimensional seismic data tied to exploration wells defines four Jurassic sequences in the northeastern Gulf of Mexico. These sequences correlate with well-known northern Gulf of Mexico basin stratigraphic units: the Louann Salt (L sequence), Norphlet and Smackover formations (N-S sequence), Haynesville Formation (H sequence), and Cotton Valley Group (C sequence). The Jurassic section overlies a basement surface characterized by broad highs (Middle Ground arch and Southern platform) and lows (Apalachicola basin and Tampa embayment). This basement structure controlled the distribution, thickness, and paleogeography of all the Jurassic sequences, but its influence became progressively less pronounced as sediment filled the basin. The Jurassic geologic history of the region is developed from an interpretation of these sequences. Well control documents the presence of Louann Salt in the Apalachicola basin, whereas in the Tampa embayment the interval is interpreted only from seismic data. Salt movement on the West Florida Shelf began early, during Norphlet-Smackover deposition, and slowed dramatically by the end of Haynesville deposition. Smackover paleogeography includes progradation of a carbonate shelf in the Apalachicola basin and the Tampa embayment, as well as development of carbonate buildups updip of basement hingelines, over basement highs, and above early salt structures. In the Apalachicola basin, Haynesville clastic sedimentation updip was coeval with carbonate deposition downdip, and a localized carbonate shelf margin developed to the southwest. Haynesville clastic sedimentation may have prevailed in the Tampa embayment, where oblique clinoforms represent shelf margin progradation. During deposition of the Cotton Valley sequence, the northeastern Gulf of Mexico was characterized by delta-plain and delta-platform sedimentation with seismically defined shelf margin progradation only in the Tampa embayment.

  4. Seismic stratigraphy of northern Green Canyon area, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mann, R.G.; Bryant, W.R.

    1986-05-01

    The Green Canyon area of the Gulf of Mexico is an active frontier exploration area of the continental slope underlain by relatively shallow salt or shale diapirs and ridges forming large intraslope basins and troughs. Analysis of more than 200 multichannel seismic profiles in this area show several seismic sequences within each basin or trough. The depositional history of the area is interpreted from the seismic sequences and seismic facies distribution within each basin. These facies are based on reflection configuration and include parallel to subparallel reflections, prograding clinoforms, hummocky clinoforms, chaotic zones, and acoustically semitransparent zones. Sigmoid and oblique progradational clinoforms are found at the shelf edge where outbuilding and aggradation occur. Hummocky clinoforms are widespread in each basin and occur in thick sequences. These grade vertically and laterally into parallel or semitransparent zones resulting in alternating reflection patterns. The parallel reflections can be interpreted as low-energy turbidites deposited during lower sea level. Chaotic zones show contorted stratal surfaces suggesting mass movement deposits. The evolution of each basin is unique. Structure and isopach maps of each sequence along with the facies distribution indicate several depositional mechanisms. These are possibly related to sea level fluctuations and shifting sediment supply. Correlation of sequences between basins and troughs is hampered in the western half of the area because of the presence of shallow subsurface diapirs and ridges, and large growth faults, and the absence of well data. Diapirs in the eastern half are less numerous and more isolated, with thicker sedimentary troughs between them because of the eastward migration of the Mississippi fan across this area in the Pliocene and Pleistocene.

  5. Messinian evaporite deposition during sea level rise in the Gulf of Lions (Western Mediterranean)

    OpenAIRE

    Bache, François; Gargani, Julien; Suc, Jean-Pierre; Gorini, Christian; Rabineau, Marina; Popescu, Speranta-Maria; Leroux, Estelle; Do Couto, Damien; Rubino, Jean-Loup; Olivet, Jean-Louis; Clauzon, Georges; Dos Reis, Antonio Tadeu; Aslanian, Daniel

    2015-01-01

    International audience The Messinian Salinity Crisis resulted from desiccation of the Mediterranean Sea after its isolation from the Atlantic Ocean at the end of the Miocene. Stratal geometry tied to borehole data in the Gulf of Lions show that the pre-crisis continental shelf has been eroded during a major sea-level fall and that sedi-ments from this erosion have been deposited in the basin. This detrital package is onlapped by high amplitude seismic reflectors overlain by the "Messinian ...

  6. Gulf and Dilmun Type seals

    DEFF Research Database (Denmark)

    Laursen, Steffen

    2011-01-01

    these Gulf Type‘ seals drew heavily on Indus Valley iconography and Indus script was occasionally employed in a pidgin-like manner. While the earliest circular seals incorporate features from Mesopotamian glyptic only to a lesser extent, this becomes a more important source of inspiration for later Dilmun...

  7. Desde el lado de la muerte: ficción y finitud en la poesía de Jaime Gil de Biedma, Alfonso Costafreda y José Ángel Valente

    Directory of Open Access Journals (Sweden)

    José Luis Fernández Castillo

    2010-11-01

    Full Text Available In his famous work The Rhetoric of temporality, Paul de Man alluded to William Wordsworth as «one of the few poets who can write prolectically about his own death and speak, as it were, from beyond their own graves». My paper explores this kind of prolectic writing about death: cases in which authors write about themselves as if they were already dead. I analyze texts of three major poets of the second half of the 20th Century: Jaime Gil de Biedma, José Ángel Valente and Alfonso Costafreda -members of the so called Generación del 50 in Spanish Poetry. My aim is to think about the philosophical implications of these fictional attempts of writing about death confronted to Heidegger's remark about the impossibility of experiencing one's death. This article contributes to clarify how experience of death in Late Modern Poetry is related to a more lucid approach to finitude once all kind of eschatological or metaphysical projections have entered a deep crisis. 

  8. Se nas pedras faz feguras parecer... Consideraciones sobre iconografía mariana y figuras poéticas en las Cantigas de Santa María de Alfonso X

    Directory of Open Access Journals (Sweden)

    Santiago Disalvo

    2014-12-01

    Full Text Available Marian iconography has been reflected in medieval Hispanic poetry in many ways, ranging from verses that describe the Virgin and her attributes to theological and mariological concepts expressed plastically by means of rhetorical forms. For example, the garden and the flowers as Holy Mary’s personal ornaments and symbols, or the image of light through a crystal or a glass window in the scenes of the Annunciation –with rich pictorial evidence throughout medieval art–, are present in poetry as symbolic descriptions of various extensions and genre, and, on the other hand, as Marian advocations or mariological tópoi as well (Ave/Eva, Flos, Hortus, Radix-Virga, Regina, Stella. Therefore, this paper proposes a general survey and a comparitive study on some of these procedures, focusing on King Alfonso X’s Cantigas de Santa Maria. In this sense, rhetorical figures, as tools that bridge the gap between the pictorial and the poetic, lead the reading towards a symbolic interpretation provided by the figuration or typologia, as postulated by Erich Auerbach for medieval textuality. Ultimately, the sacred value of Marian images (an inheritance of Byzantine iconic art is represented also in the miracles of the Cantigas de Santa Maria, a masterpiece that shows a strong influence of the iconodulic doctrine.

  9. The U.S. Geological Survey`s National Coal Resource Assessment: The Northern and Central Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, L.; Bragg, L.; Tewalt, S. [Geological Survey, Reston, VA (United States)

    1996-09-01

    The US Geological Survey (USGS) Energy Resource Surveys Program is currently conducting a five-year National Coal Resource Assessment project. Primary focus is on the quality and quantity of top-producing coal beds and coal zones in five of the nine major coal producing regions in the US. These regions include the (1) Northern and Central Appalachian Basin, (2) Gulf Coastal Plain, (3) Illinois Basin, (4) Colorado Plateau, and (5) Powder River Basin and Northern Great Plains.

  10. Interpretation of crustal structure from regional gravity anomalies, Ouachita Mountains area and adjacent Gulf coastal plain

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, J.M.; Keller, G.R.

    1986-06-01

    A gravity data base from more than 35,000 stations was used to generate a series of regional gravity maps of the Ouachita Mountains area including adjacent parts of the craton and the Gulf coastal plain. These maps were used in conjunction with information from 96 wells, data from preexisting geophysical and geological investigations, and computer models to interpret four gravity profiles that transect the study area (approximately lat. 30-37/sup 0/N, long. 91.5-99/sup 0/W). These models, gravity maps, and previous investigations were then used to analyze various regional gravity anomalies and to interpret the gross crustal structure of the region and its tectonic implications. These data suggest that variably attenuated continental crust lies beneath the Gulf coastal plain, south of the Ouachita system gravity gradient, as opposed to typical continental crust of the craton north of this gradient. This variation in crustal structure probably reflects the complexity of Eocambrian and early Mesozoic rifting in the area. The Arkoma basin gravity minima may result from the combined effect of a late Paleozoic foreland basin and an Eocambrian northwest-trending, rift-related basin. The Ouachita system interior zone gravity maximum varies along strike of this orogenic belt. This anomaly appears to be a good indicator of the position of the Eocambrian continental margin and associated rift zone. Gravity anomalies in the Gulf coastal plain appear to be a combined effect of variable crustal attenuation, basins and uplifts, and mafic intrusions. Gravity maxima in the southern Oklahoma aulacogen result from uplifts and deep-seated mafic intrusions; gravity minima result from deep sedimentary basins.

  11. Thermal Evolution of the North-Central Gulf Coast

    Science.gov (United States)

    Nunn, Jeffrey A.; Scardina, Allan D.; Pilger, Rex H., Jr.

    1984-12-01

    The subsidence history of the North Louisiana Salt Basin, determined from well data, indicates that the region underwent extension during rifting and has since passively subsided due to conductive cooling of the lithosphere. Timing of the rifting event is consistent with opening of the Gulf of Mexico during Late Triassic to Early Jurassic time. Crustal extension by a factor of 1.5 to 2 was computed from "tectonic" subsidence curves. However, data from the early subsidence history are insufficient to distinguish between uniform and nonuniform extension of the lithosphere. The magnitude of extension is in good agreement with total sediment and crustal thicknesses from seismic refraction data in the adjacent Central Mississippi Salt Basin. The temperature distribution within the sediments is calculated using a simple heat conduction model. Temperature and subsidence effects of thermal insulation by overlying sediments are included. The computed temperature distribution is in good agreement with bottom hole temperatures measured in deep wells. Temperature histories predicted for selected stratigraphic horizons within the North Louisiana Salt Basin suggest that thermal conditions have been favorable for hydrocarbon generation in the older stata. Results from a two-dimensional heat conduction model suggest that a probable cause for the early formation of the adjacent uplifts is lateral heat conduction from the basin. Rapid extension of the lithosphere underneath areas with horizontal dimensions of 50-100 km produces extremely rapid early subsidence due to lateral heat conduction. The moderate subsidence rate observed in the North Louisiana Salt Basin during the Jurassic and Early Cretaceous suggests slow extension over a long period of time.

  12. GuLF Study: The Gulf Long-Term Follow-Up Study

    Science.gov (United States)

    ... font size, or print this page. The GuLF STUDY Gulf Study Newsletter Learn more about the 33,000 people ... linkage to cancer and mortality records. The GuLF STUDY wants you! If you completed a telephone interview ...

  13. 76 FR 54375 - Safety Zone; Thunder on the Gulf, Gulf of Mexico, Orange Beach, AL

    Science.gov (United States)

    2011-09-01

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Thunder on the Gulf, Gulf of Mexico, Orange... establishing a temporary safety zone for a portion of the Gulf of Mexico for the waters off Orange Beach... Mexico, south of Orange Beach, Alabama to occur from October 6, 2011 through October 9, 2011. This...

  14. Integrated well-log, seismic, and biostratigraphic approach to sequence stratigraphy in Late Cenozoic expanded sections, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mitchum, R.M. Jr. (R M Mitchum Exploration Inc., Houston, TX (United States)); Sangree, J.B. (Sangree Exploration Inc., Houston, TX (United States)); Vail, P.R. (Rice Univ. Houston, TX (United States)); Wornar, W.W. (Microstrat Inc., Houston, TX (United States))

    1991-03-01

    Increased emphasis on well-log signatures and recognition criteria for stratigraphic sequence boundaries, systems tracts, and condensed sections in a sequence-stratigraphic context has enhanced facies interpretation and reservoir prediction capabilities. Integration of well logs with high-resolution biostratigraphy and paleobathymetry, high-quality seismic configuration data, and the latest eustatic cycle chart provides the best data base for sequence-stratigraphic analysis. This approach is particularly effective for thick, rapidly deposited slope and basin sediments, such as in the Plio-Pleistocene of the Gulf of Mexico basin. The general sequence-stratigraphic model consists of a depositional sequence with lowstand basin floor fan, slope fan, and prograding complex, transgressive systems tract, and highstand systems tract. Each systems tract is deposited at a predictable position in an interpreted eustatic cycle and has recognizable signatures in well logs and seismic data. Any given basin to which this model is applied is strongly controlled by its own tectonic subsidence and accommodation history, and by the type and rate of sediment supply, but the higher frequency eustatic cyclicity is superposed on the other basinal controls. A typical depositional model for the Plio-Pleistocene of the Gulf of Mexico basin is a diapir-controlled subbasin associated with a large contemporaneous expansion fault. The environment of deposition is closely related to the history of fault development. Reservoir sand distribution is characteristic and predictable for each systems tract. Carefully planned evaluation and completion techniques are based on these characteristics.

  15. Carbon sources and fates in the Gulf of Papua

    Science.gov (United States)

    Goni, M. A.; Monacci, N. M.; Gisewhite, R. A.; Ogston, A.; Crockett, J.; Nittrouer, C.

    2006-12-01

    Seabed sediments were collected along the particle-dispersal system associated with the Fly River-Gulf of Papua continental margin as part of the source to sink program in Papua New Guinea. Box and kasten cores were collected from the subaqueous delta located adjacent to the mouth of the Fly River as well as from the topset, foreset and bottomset regions of the active clinoform in the northern region of the Gulf of Papua. Analyses of elemental (organic carbon, inorganic carbon, nitrogen), stable isotopic (d13C and d15N), radiocarbon (14C), and biomarker (CuO oxidation products) signatures reveal significant differences in the content and composition of sedimentary organic matter (OM) along the dispersal system. The major sources of OM to the system appear to be remains of vascular plants, soil OM from the drainage basin, and materials derived from autochthonous productivity. The geographical contrasts in the concentrations and accumulation fluxes of these distinct types of allochthonous and autochthonous OM are presented in the context of patterns of sediment transport and deposition within the region. An overall OM budget for the whole dispersal system will be presented and its implication for carbon sequestration in fluvial-dominated continental margins discussed.

  16. Geohydrolic studies of Gulf Coast interior salt domes

    International Nuclear Information System (INIS)

    Disposal of high-level radioactive wastes in Gulf Coast salt domes requires that the cavities be free from groundwater dissolution for 250,000 years. Salinity variations of groundwater near selected domes were investigated. Saline groundwater anomalies (saline plumes) in aquifers pierced or uplifted by the dome may be the result of salt solution by groundwater. In the Northeast Texas salt dome basin electric logs of oil and gas wells have been used to estimate groundwater salinities in aquifers near selected domes. Thus far, the analyses have revealed saline groundwater anomalies around 4 of the 9 domes studied. Estimates of the rate of salt dissolution from domes associated with saline groundwater plumes indicate that less than 30 meters of salt will be removed from the upper surfaces of the dome in 250,000 years. Thus, these preliminary studies show that even apparently unstable domes may be sufficiently stable to serve as waste disposal sites. 6 figures

  17. Geology of the Warda discovery, Gulf of Suez, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Vargo, J.N.; Greet, M.J.; Collings, B.P.; Davis, C.B.; Miller, M.H. (BG Services Inc., Houston, TX (United States))

    1991-08-01

    British Gas, as operator for its partners, Yukong Ltd., and Union Pacific Petroleum Suez Ltd., recently discovered the Warda field in the Gulf of Suez in November 1990. Discovery well Hb78-2, located 4 km off the mouth of the Wadi Araba on the west side of the north-central Gulf of Suez, reached a total depth of 8,400 ft in Nubia clastics. Oil was tested in the Hb78-2 from five separate clastic intervals at a cumulative flow rate of approximately 7,000 BOPD of 20-24{degree} API with no water. Currently, an appraisal well program is underway to extend the limits of the field. This significant new-field discovery is located in a part of the Suez basin that previously considered to have limited oil potential. Geophysical assessment of the structure used exploration 3-D seismic coverage and concurrently acquired potential-fields datasets. The Warda structure at Kareen-Rudeis levels is a broad four-way closure, trending northwest-southeast, which drapes over older pre-Miocene tilted fault blocks. The Warda structure lies downthrown to a major Clysmic shoulder fault and is bounded on the northeast by another Clysmic down-to-the-basin normal fault. Cross faulting is noted at the deeper levels, and particularly influences the rift boundary faults. According to burial-history modeling, oil generation occurred within 4-5 million years after the Eocene-Senonian carbonate source rocks achieved onset of oil generation at a birthline of 10,000-11,000 ft subsea. The Cretaceous-Carboniferous Nubia sandstones apparently have acted as a conduit for oil migration from the adjacent Lagia hydrocarbon kitchen a few kilometers to the northeast.

  18. CEOs: Gulf crisis hits hospitals' bottom line.

    Science.gov (United States)

    Johnsson, J

    1990-12-01

    Hospital CEOs say the Persian Gulf crisis could hit them hard where it counts. In fact, hospitals are already seeing some adverse impact from events in the Middle East. From fundraising to plant management to strategic planning, the confrontations in the Gulf are having an impact on the hospital's bottom line.

  19. Fishery potential of the Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Govindan, K.; Ramaiah, Neelam; Gajbhiye, S.N.

    Fishery potential of the interior Gulf of Kachchh and adjacent creek regions was reported for the first time as baseline data for future ecological assessment. The experimental trawling and gill netting indicated that the inner Gulf (av. 7.8 kg...

  20. Diseño e implementación de una estrategia didáctica para la enseñanza-aprendizaje de la Tabla Periódica y sus propiedades en el grado octavo utilizando las nuevas tecnologías TICs: estudio de caso en la Institución Educativa Alfonso López Pumarejo grupo 8-2

    OpenAIRE

    Causado Moreno, Ana Victoria

    2012-01-01

    Esta propuesta tiene como intención diseñar e implementar una estrategia didáctica para la enseñanza-aprendizaje de la Tabla Periódica y sus propiedades con el uso de las Tecnologías de la Información y de la Comunicación (TICs) en el grado octavo de la Institución educativa Alfonso López Pumarejo. La propuesta consiste en utilizar una herramienta virtual de aprendizaje como lo es la plataforma moodle, diseñar un curso virtual sobre el tema de tabla periódica para los estudiantes del grupo...

  1. Distribution of surficial sediments in the Southern Evoikos and Petalioi Gulfs, Greece

    Directory of Open Access Journals (Sweden)

    A.P. KARAGEORGIS

    2012-12-01

    Full Text Available A series of 123 surficial sediment samples from the Southern Evoikos and Petalioi Gulfs was studied for grain-size properties, carbonate content and mineralogical composition. Distribution of the sediments revealed two sedimentary provinces. The first concerns the Southern Evoikos Gulf, characterised by silty sediments with relatively low carbonate content. Quartz, feldspars, micas, clay and carbonate minerals are the major mineralogical components of the sediments. These sediments are the result of the Asopos River supply during Holocene and they contribute to the formation of smooth bottom morphology. The second province concerns the Petalioi Gulf (Northern and Southern, where the surficial sediments are mainly sandy and characterised by very high carbonate content. Their mineralogical composition reflects the lithology of the drainage basin. Since the modern terrigenous solid supply is limited, these sediments are not considered as products of recent sedimentation, but older deposits (relict sands. Their presence at such depths is justified by sea-level fluctuations and their preservation is due to the low sedimentation rate in the Petalioi Gulf, in combination with the strong hydrodynamic status of the area.

  2. Thermocline Regulated Seasonal Evolution of Surface Chlorophyll in the Gulf of Aden

    KAUST Repository

    Yao, Fengchao

    2015-03-19

    The Gulf of Aden, although subject to seasonally reversing monsoonal winds, has been previously reported as an oligotrophic basin during summer, with elevated chlorophyll concentrations only occurring during winter due to convective mixing. However, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) ocean color data reveal that the Gulf of Aden also exhibits a prominent summer chlorophyll bloom and sustains elevated chlorophyll concentrations throughout the fall, and is a biophysical province distinct from the adjacent Arabian Sea. Climatological hydrographic data suggest that the thermocline, hence the nutricline, in the entire gulf is markedly shoaled by the southwest monsoon during summer and fall. Under this condition, cyclonic eddies in the gulf can effectively pump deep nutrients to the surface layer and lead to the chlorophyll bloom in late summer, and, after the transition to the northeast monsoon in fall, coastal upwelling driven by the northeasterly winds produces a pronounced increase in surface chlorophyll concentrations along the Somali coast. © 2015 Yao, Hoteit.

  3. Regional Geophysical Surveys and Crustal Structure of the Gulf of Mexico

    Science.gov (United States)

    Rodríguez-Chavez, F.; Fucugauchi, J. U.

    2007-05-01

    Results of processing and modeling of anomaly data from regional geophysical surveys in the southern sector of the Gulf of Mexico are presented. The Gulf of Mexico has been intensively studied for several years, mainly because of the economic potential of the oil and gas resources. The basin may have formed by sea-floor spreading, rifting and lateral translation/rotation of continental slivers ssociated with major break-up and drifting apart of North and South America continental plates in the mid Mesozoic. Major structural features and crustal structure, including the continent-ocean transition and Gulf coastal passive margin are relatively poorly understood. Aerogeophysical gravity and magnetic surveys have been conducted and data are processed and modeled to investigate on the Gulf crustal structure. Spectral statistical estimates of regional basement depths derived from aeromagnetics give mean depths of 8000 m. Estimates derived from gravity anomalies are in the order of 10000 m. Depths derived from 2D and 3D seismic reflection surveys conducted for oil exploration purposes in selected areas indicate average depths to basement from 6000 m to values grater than those derived from potential field data.

  4. Evolution of Pre-Jurassic basement beneath northern Gulf of Mexico coastal plain

    Energy Technology Data Exchange (ETDEWEB)

    Van Siclen, D.C.

    1990-09-01

    Data from the northern Gulf Coast region reveal a late Paleozoic wrench fault system along which North America (NA) moved southeast (present directions) alongside the northeastern edge of future South America (SA), to where collision with that continent converted a broad continental embankment off the Southern Oklahoma aulacogen into the Ouachita thrust belt. At the same time, Africa farther east, to which protruding SA was firmly joined, was continuing to advance the Appalachian thrusts on the opposite side of these faults. This relationship left no space between the American continents for the conventional remnant ocean or microcontinents. By Late Triassic time, however, extension south of the Ouachita Mountains was forming the series of Interior rift basins, at both ends of which new wrench faults transferred the extension southward to the DeSoto Canyon and South Texas rift basins. Genetically, the Ouachita thrusts are part of the subduction zone along the front of a former SA forearc basin, which continued to receive marine sediments into middle Permian. The Wiggins arch southeast of it is a sliver of that continent, left with NA when the Interior basin rifting jumped from that forearc basin southward across bordering outer basement highs to begin opening the deep Gulf of Mexico (GOM) basin. The Late Triassic crustal extension resulted from right-lateral translation of NA around the bulge of northwestern Africa. About 200 mi of this placed Cape Hatteras against Africa's Cap Blanc, in the configuration from which the magnetic data indicate spreading began in the Central North Atlantic Ocean. The reality of this translation is confirmed by widespread rifting at the same time in western North Africa and between all three northern Atlantic continents; this drew the tip of the Tethys sea southward to Cape Hatteras and led to deposition of voluminous Late Triassic red beds and evaporites along it.

  5. 78 FR 14225 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery...

    Science.gov (United States)

    2013-03-05

    ..., Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery; 2013 Accountability Measure for Gulf of Mexico Commercial Gray Triggerfish AGENCY: National Marine Fisheries Service (NMFS), National... Mexico (Gulf) reef fish fishery for the 2013 fishing year through this temporary final rule....

  6. Alaska, Gulf spills share similarities

    International Nuclear Information System (INIS)

    The accidental Exxon Valdez oil spill in Alaska and the deliberate dumping of crude oil into the Persian Gulf as a tactic of war contain both glaring differences and surprising similarities. Public reaction and public response was much greater to the Exxon Valdez spill in pristine Prince William Sound than to the war-related tragedy in the Persian Gulf. More than 12,000 workers helped in the Alaskan cleanup; only 350 have been involved in Kuwait. But in both instances, environmental damages appear to be less than anticipated. Natures highly effective self-cleansing action is primarily responsible for minimizing the damages. One positive action growing out of the two incidents is increased international cooperation and participation in oil-spill clean-up efforts. In 1990, in the aftermath of the Exxon Valdez spill, 94 nations signed an international accord on cooperation in future spills. The spills can be historic environmental landmarks leading to creation of more sophisticated response systems worldwide

  7. Investigation of heavy metal pollutants at various depths in the Gulf of Izmit

    International Nuclear Information System (INIS)

    Highlights: • Monitoring seasonal variations in heavy metal pollution. • Heavy metal levels according to depth in seawater from the Gulf of Izmit. • Industrial activity and biological life co-exist in Izmit Bay. -- Abstract: In this study, we report results concerning the accumulation of heavy metals in seawater from Izmit Bay. The bay was divided into the three parts: the eastern, the central and the western basins. The goal of this study was to determine levels of heavy metals at various depths in the bay between April 2008 and May 2010. Liquid–liquid extractions were performed on seawater samples. An atomic absorption spectrophotometer was used to measure levels of six metals: lead, cadmium, chromium, iron, manganese and zinc. We applied our results to evaluate the status of pollution in the Gulf of Izmit. Significant seasonal differences in metal concentrations and higher concentrations of many metals in water near the shore are evidence for uncontrolled release of pollutants in the water

  8. Solar forcing of Gulf of California climate during the past 2000 yr suggested by diatoms and silicoflagellates

    Science.gov (United States)

    Barron, John A.; Bukry, David

    2007-01-01

    High-resolution records of the past 2000 yr are compared in a north–south transect (28° N to 24° N) of three cores from the eastern slopes of the Guaymas, Carmen, and Pescadero Basins of the Gulf of California (hereafter referred to as the “Gulf”). Evenly-spaced samples from the varved sediments in each core allow sample resolution ranging from ∼ 16 to ∼ 37 yr.

  9. Leviathan moving to expand Gulf gas system

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-15

    This paper reports that Leviathan Gas Pipeline Co., Houston, has advanced plans for a large deepwater pipeline gathering system in the Gulf of Mexico. Under an agreement between Deep-Tech International Inc. and Transco Energy Co., Leviathan will pay $65 million for Transco interests in several gulf gas gathering pipelines and related facilities. Leviathan is a Deep Tech subsidiary. Gulf pipeline assets Leviathan acquired from Transco include Louisiana Offshore Pipeline Systems (LOPS), Green Canyon Pipeline Co., and companies owning at 40% interest in High Island Offshore System (HIOS) and a 33 1/1% interest in United Texas Offshore System (UTOS).

  10. Host rock geology and geochemistry of the Zona uranium occurrence, Peta Gulf Syncline (Upper Benue Trough), northeast Nigeria

    Science.gov (United States)

    Suh, C. E.; Dada, S. S.; Matheis, G.

    2000-11-01

    The Peta Gulf Syncline (Upper Benue Trough, northeast Nigeria) is a fault-bounded pull-apart sub-basin. The boundary faults are mainly northeast-southwest-trending en echelon strike-slip faults, truncated along their lengths by normal and tear faults with stepovers. The eastern marginal faults underwent rotation during sedimentation, whereas the steeply dipping western marginal faults were inactive. The Peta Gulf Sub-basin is filled by the Bima Sandstone Formation (Lower Cretaceous) which has three siliciclastic members: (i) B 1: medial fan coarse-grained to microconglomeratic sandstones; (ii) B 2: full fluvial medium-grained sandstones with minimal fines; and (iii) B 3: lacustrine and flood basin deposits comprising alternating fine-grained sandstones and siltstones/claystones. Sediment supply was from east to west and facies changes show a general fining in this direction. B 3 offers the most favourable environment/lithology for U concentration. The only significant U occurrence in the Peta Gulf Syncline is the Zona U anomaly, which occurs within transitional B 2-B 3 brecciated sandstones with wall rock alterations zones. The mineralised zone has elevated SiO 2, Fe, As, Ba and W levels but is depleted in the alkalis, Zr, Rb and Sr. This chemical zonation supports the epigenetic orgin of this anomaly.

  11. Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico

    Science.gov (United States)

    Alexander; Smith; Schwarz

    2000-02-17

    An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of benthic communities and stress in fishery resources. There is evidence for a predominantly anthropogenic origin of the increased nitrogen flux, but the location of the most significant sources in the Mississippi basin responsible for the delivery of nitrogen to the Gulf of Mexico have not been clearly identified, because the parameters influencing nitrogen-loss rates in rivers are not well known. Here we present an analysis of data from 374 US monitor ing stations, including 123 along the six largest tributaries to the Mississippi, that shows a rapid decline in the average first-order rate of nitrogen loss with channel size--from 0.45 day (-1) in small streams to 0.005 day (-1) in the Mississippi river. Using stream depth as an explanatory variable, our estimates of nitrogen-loss rates agreed with values from earlier studies. We conclude that the proximity of sources to large streams and rivers is an important determinant of nitrogen delivery to the estuary in the Mississippi basin, and possibly also in other large river basins.

  12. Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico

    Science.gov (United States)

    Alexander, R.B.; Smith, R.A.; Schwarz, G.E.

    2000-01-01

    An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of benthic communities and stress in fishery resources. There is evidence for a predominantly anthropogenic origin of the increased nitrogen flux, but the location of the most significant sources in the Mississippi basin responsible for the delivery of nitrogen to the Gulf of Mexico have not been clearly identified, because the parameters influencing nitrogen-loss rates in rivers are not well known. Here we present an analysis of data from 374 US monitoring stations, including 123 along the six largest tributaries to the Mississippi, that shows a rapid decline in the average first-order rate of nitrogen loss with channel size-from 0.45 day-1 in small streams to 0.005 day-1 in the Mississippi river. Using stream depth as an explanatory variable, our estimates of nitrogen-loss rates agreed with values from earlier studies. We conclude that the proximity of sources to large streams and rivers is an important determinant of nitrogen delivery to the estuary in the Mississippi basin, and possibly also in other large river basins.

  13. High heat flow and ocean acidification at a nascent rift in the northern Gulf of California

    Science.gov (United States)

    Prol-Ledesma, Rosa Ma; Torres-Vera, Marco-Antonio; Rodolfo-Metalpa, Riccardo; Ángeles, Catalina; Lechuga Deveze, Carlos H.; Villanueva-Estrada, Ruth Esther; Shumilin, Evgueni; Robinson, Carlos

    2013-01-01

    The prevailing tectonic setting in the Gulf California suggests the presence of an undetermined number of short spreading centres with associated hydrothermal systems. However, to date, active seafloor spreading phenomena have been documented in only three of the eight tectonically active basins. Here we report heat flow values as high as 15,436 mW m−2 in two of the northernmost basins of the Gulf of California, providing evidence of intense hydrothermal activity associated with the transition from continental rifting to seafloor spreading. The mean heat flow for the Wagner and Consag basins area is 1,875 mW m−2, more than 15 times higher than the mean value for oceanic crust (105.4 mW m−2). Additional evidence for vigorous hydrothermal circulation and a shallow heat source includes intense gas discharge (CO2 and CH4), widespread low pH (average 7.7), locally high 222Rn concentrations in the bottom water and a high extent of organic matter maturation in the sediments. PMID:23340428

  14. Alleghenian Reconstruction and Subsequent Evolution of the Gulf of Mexico, Bahamas, and Proto-Caribbean

    Science.gov (United States)

    Pindell, James L.

    1985-01-01

    A detailed model for the evolution of the Gulf of Mexico, the Bahamas and the Proto-Caribbean is built within the framework provided by a detailed initial Alleghenian (western Pangean) reconstruction and an accurate subsequent relative-motion history between North America and Gondwana (northern Africa and South America). The Alleghenian reconstruction closes all pre-Jurassic oceans; accounts for Jurassic attenuation of continental crust by restoring that attenuation to original prerift continental thicknesses; incorporates an improved Equatorial Atlantic fit between northern Brazil and the Guinea margin of Africa; quantitatively removes changes in shape of northern South America due to Late Cretaceous and Cenozoic accretion and internal deformation; includes pre-Mesozoic continental crust presently underlying the western Bahamas and southern Florida; and correlates Late Paleozoic geology of Yucatan with its neighboring continental masses. Extension occurred within the Gulf of Mexico from Late Triassic to earliest Cretaceous time, but seafloor spreading was delayed until the Late Callovian. This divided a single Gulf-wide salt basin into the Louann and Campeche salt provinces. The Yucatan block progressively rotated about 43 degrees counterclockwise away from the Texas-Louisiana margin around a pole in northern Florida. The Tamaulipas-Golden Lane-Chiapas fault zone of eastern Mexico is interpreted as the remains of an initially intracontinental transform system along which Yucatan migrated. Attenuated continental crust beneath southern Florida and the western Bahamas, termed here the Florida Straits block, migrated approximately 300 km out of the eastern Gulf, approximately along Central Atlantic flow lines. These rotations are consistent with recently suggested magnetic anomaly trends in the Gulf of Mexico (Shepherd et al., 1982; S. Hall, personal communication, 1984). The Proto-Caribbean formed synchronously by a fan-like rotation of Yucatan away from Venezuela.

  15. Crustal structure in Gulf of Mexico from OBS refraction and multichannel reflection data

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, A.K.; Carye, J.; Latham, G.; Buffler, R.T.

    1981-07-01

    Results from 12 reversed refraction profiles each 110 km long have been combined with multichannel reflection data to produce a series of crustal structure sections across the Gulf of Mexico. The refraction data were collected using ocean bottom seismographs (OBS) and explosive charges ranging in size from 1 to 120 lb (0.45 to 54.42 kg). These data show as many as three layers of sedimentary rocks with total thickness between 5 and 9 km and layer velocities between 1.7 and 3.5 km/sec. Beneath most of the Gulf, this sedimentary section is underlain by a layer with velocity between 4.5 and 5.4 km/sec. The acoustic basement as defined by reflection data is confined within this layer. This basement layer, which may be the top of volcanic layer 2, is too thin to be detected in the refraction results. Beneath this layer in most of the deep Gulf is an oceanic crustal layer (layer 3), 3 to 6 km thick which thickens to about 12 km under the Mississippi fan and 10 km in the southeastern Gulf where it is interpreted to be transitional crust. Oceanic layer 3 has a velocity between 6.4 and 7.0 km/sec and overlies a mantle with velocity between 7.6 and 8.2 km/sec. The top of oceanic layer 3 was not observed on regional multichannel seismic profiles. These data confirm earlier refraction interpretation that most of the deep Gulf basin is underlain by an oceanic crustal layer flanked by transitional crust. This layer may have been formed by a mantle thermal event accompanied by a period of rapid sea-floor spreading. 16 figures, 1 table.

  16. Anticlines in the US Gulf Coast [anticlineg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset of anticlines is intended primarily for reference; it includes major structures such as those shown on Plate 2, Principal structural features, Gulf of...

  17. Northern Gulf Coast Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions in the Gulf of Mexico....

  18. Central Gulf of Alaska Rockfish Permit Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific Fishery Management Council adopted the Central Gulf of Alaska Rockfish Program (Rockfish Program) on June 14, 2010, to replace the expiring Pilot...

  19. ROE Gulf of Mexico Hypoxia Sample Locations

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset describes dissolved oxygen levels in the Gulf of Mexico. Individual sampling sites are represented by point data. The background polygon shows areas...

  20. Gulf of Mexico Ecosystem Status Report

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Gulf of Mexico is one of the most ecologically and economically valuable marine ecosystems in the world and is affected by a variety of natural and...

  1. Gulf cooperation council: Problems and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, S.

    1985-01-01

    Few other regions in the world have as much strategic, economic, and political significance for the Western world as does the Persian Gulf. Oil and economics are only two factors. Geopolitics and strategic location are also critical.

  2. Gulf Coast Vulnerability Assessment and Conservation Framework

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The proposed partnership to support a Gulf Coast Landscape Conservation Liaison will provide much needed coordination across multiple programs and partnerships to...

  3. Seasonal Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are seasonal composites, and were...

  4. Monthly Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are monthly composites, and were calculated...

  5. 2013 Gulf of Mexico SPCE angler survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This survey provides economic data related to marine recreational fishing in the Gulf of Mexico. The data collected include preference and opinion information...

  6. Southeast Gulf of Mexico Sperm Whale Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large vessel surveys were conducted during the summers of 2012 and 2014 in the southeastern Gulf of Mexico north of the Dry Tortugas. Data were collected on the...

  7. Seismotectonics and Seismic Waves Transmision Characteristics of the Gulf of Mexico

    Science.gov (United States)

    Yamamoto, J.; Ruiz, V. H.

    2013-05-01

    Mexico's energy resources reside largely in the Gulf of Mexico Basin, one of the oil producing areas of greatest potential in the world. Recent scientific and technological advances on provide new insights that open new areas for exploration and exploitation that were unthinkable in the past, as in the case of the deepwater Gulf of Mexico. Investigate the characteristics of this region from different perspectives should be a national priority. This research is an effort in that direction. This work consists of two parts in the first we examine the spatial distribution of seismicity and focal mechanisms of major earthquakes in the Gulf of Mexico (GM). In particular we discuss the mechanism of rupture of the event (Mw 5.9) of 10 September 2006 located off the coast of Florida, United States of America and the May 23, 2007 (Mw 5.4) off the coast of Tuxpan, Veracruz. These two are the most relevant events occurred within the basin of GM in recent years. In the second part we study the inelastic attenuation of seismic signals in the GM by analyzing the decay of the coda of the S wave and surface waves in some cases. The attenuation is estimated by calculating the quality factor Q for different paths within the basin in the frequencies range of 0.3 to 4.0 Hz. It is assumed that the Q factor is governed by the equation Q(f)=Qof**n where Qo is the value of Q (f) at 1 Hz. The calculation uses the broadband digital records of five events of medium magnitude (5.2 <= Mw <= 7) occurred off the coast of Florida and Veracruz recorded by the IRIS and SSN networks. Data from the 2010 Haiti earthquake is used for comparison purposes.

  8. Qatar Peninsula, United Arab Emirates, Persian Gulf

    Science.gov (United States)

    1983-01-01

    In this view of the Qatar Peninsula, United Arab Emirates, Persian Gulf, (25.0N, 51.0E) a large oil spill, seen as a large dark toned mass in the water covers much of the surface of the western Persian Gulf. Qatar is one of several of the oil rich United Arab Emirate states. Oil spills and oil pollution of the environment are common occurrances associated with oil tanker loading operations.

  9. No evidence for altered cellular immune functions in personnel deployed in the Persian Gulf during and after the Gulf War--The Danish Gulf War study

    DEFF Research Database (Denmark)

    Bregenholt, S; Ishøy, T; Skovgaard, L T;

    2001-01-01

    analyzed the peripheral blood natural killer (NK) cell activity of 686 Gulf War personnel who had been present in the Persian Gulf area during and immediately after the Gulf War as well as 231 gender and age-matched controls. The test material included individual samples of frozen peripheral blood...

  10. Climate forcing, primary production and the distribution of Holocene biogenic sediments in the Gulf of California

    Science.gov (United States)

    Douglas, Robert; Gonzalez-Yajimovich, Oscar; Ledesma-Vazquez, Jorge; Staines-Urias, Francisca

    2007-01-01

    The Gulf of California is a marginal seaway under the influence of a monsoon climate that produces cool, dry winters and warm, humid summers. Winds, tidal mixing and coastal-trapped waves forced by climate and the Pacific Ocean control nutrient advection and primary productivity (PP). Strong northwest winds from the subtropical East Pacific High Pressure system begin in November and last until April and drive coastal upwelling along the mainland margin, especially in the central and southern Gulf. In the northern Gulf, particularly around the midrift island, tidal mixing and turbulence occurs year round, advecting nutrients into the mixed layer and high productivity. During summer and early fall months, winds are variable, of less intensity and mainly blow cross-basin except in the most northern Gulf. Summer PP is generally low in the central and southern Gulf except along the mainland where coastal-trapped waves associated with tropical surges and hurricanes generate mixing over the continental shelf. Mesoscale eddies or gyres often associated with jets and filaments extend to depths of 1000 m and transport nutrient-enriched upwelled waters and plankton detritus across the Gulf. The largest and most persistent gyres rotate in an anti-cyclonic direction (east to west) and are a principal source of the plankton export to the peninsula margin. Two major biogenic sediment patterns are present in core-top sediments. Hemipelagic biosiliceous-rich muds are accumulating beneath upwelling areas of high productivity in the central Gulf and along the mainland margin. Calcium carbonate- and organic carbon-rich (OC) sediments are concentrated along the peninsula margin, generally beneath lower productivity waters with the highest OC content in areas with the lowest productivity. The high, uniform biosiliceous content in Guaymas basin, extending southward into Carmen basin reflects the redistribution by mesoscale gyres of phytoplankon debris produced in mainland coastal

  11. Seismic stratigraphy and salt tectonics of upper Continental Slope, East Breaks flexure trend, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gardiner, W.B.

    1986-05-01

    A study of more than 1200 of 72-fold, migrated, seismic reflection profiles, from the eastern part of the East Breaks flexure trend, Gulf of Mexico, indicates that, although individual seismic reflectors cannot be traced across the entire area, seismic depositional units can be recognized and correlated from basin to basin in most instances. Three tentative conclusions are evident from this study: (1) salt diapirs appear to have grown through a series of intermittent movements to form structurally separate intraslope basins; (2) sedimentation is probably channeled by differential dome growth, which creates local stratigraphic differences between basins; and (3) packages of distinctive seismic depositional units can be successfully used to map sediment cycles between separate basins. Fluctuations of Pleistocene sea level appears to be the dominate depositional control on the upper continental slope in this area. During high sea level stands, turbidity currents were confined to depressions between diapirs, whereas pelagic deposition blanketed the slope. But during low sea level stands, sediment bypassed the shelf and deposited directly onto the upper slope, which increased the sediment load and helped initiate diapirism. Repeated sea level fluctuation would then lead to the cyclic pattern of seismic depositional packages that is commonly seen on upper slope seismic records.

  12. Major reproductive health characteristics in male Gulf War Veterans. The Danish Gulf War Study

    DEFF Research Database (Denmark)

    Ishøy, T; Andersson, A M; Suadicani, Poul Vilhelm;

    2001-01-01

    The male reproductive system could have been affected by various hazardous agents and exposures during and in the aftermath of the Persian Gulf War scenario. We tested the hypothesis that, compared to controls, male Danish Gulf War Veterans would have adverse sex hormone levels, decreased fertility...

  13. Contamination from gold and platinum-group metals mining in the Gulf of Darién, Colombia

    Science.gov (United States)

    Vasquez-Bedoya, L.; Palacio Baena, J.

    2013-12-01

    Gulf of Darién, triangular southernmost extension of the Caribbean Sea, bounded by Panama on the southwest and by Colombia on the southeast and east. The Gulf is made up of 17 municipalities in the department of Choco and Antioquia. The Gulf of Darién is a geostrategic region, rich in biodiversity, known for its natural resources of minerals, oil, lumber as well as its water and fertile land. The Darién also acts as the bridge between South America and Central America and has access to the Pacific Ocean and the Caribbean Sea. The economy in the region is based mainly on agribusinesses, tourism and mining activities, mainly the 'mining of gold and platinum-group metals'. In our study we determined the degree of trace element contamination in estuarine sediment samples originated from mining activities and municipal waste water discharges of effluents on the gulf of Darién. . Surface samples were taken from 17 locations through the entire Gulf. Grain size, Corg, Ag, Al, Ca , Cr, Cu, Fe, Mg, Mn, Na, Ni, Pb and Zn concentrations were analyzed, and enrichment factors (EF) as well as geo-accumulation indices (Igeo) were calculated. Concentrations of Pb, Zn, Ni, Cu and Cr show levels that are consistent with those typically found in urbanized marine environments. EF and Igeo values revealed that the Gulf is extremely contaminated with Ag and moderately contaminated with Cr and Zn. The sources of Cr, Ag, Hg and Zn are associated with the development of mining activities in the Atrato River basin. The observed enrichment of Ag may be explained as a residue of the extraction of gold and platinum-group metals.

  14. Status of Flora and Fauna of Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.

    developments are planned in an ecofriendly manner to maintain the high productivity and biodiversity of the Gulf region. In this context, Department of Ocean Development, Government of India is planning a strategy for management of the Gulf adopting...

  15. Gulf Coast hurricane activity and climate variability during the last half of the Holocene

    Science.gov (United States)

    Lane, P.; Donnelly, J. P.

    2011-12-01

    The dominant timescales of variability in a 4500-year sediment-based storm chronology from the northeastern Gulf of Mexico are identified, and relationships between storm frequency and climate are explored. Changes in the frequency of large storm surge deposits in the record likely represent variability in the intensity distribution of hurricanes impacting the site during the late Holocene. Significant variability at approximately 200 and 1000-year timescales that was detected in the storm record is shared by numerous Holocene climate records including reconstructions of Loop Current penetration into the Gulf of Mexico. Intense storm landfalls were most frequent around 3.7 ka, between 2.7 and 2.4 ka, and around 0.7 ka when foraminiferal proxies of mixed layer depth indicate a more permanent residence of the Loop Current within the northeastern Gulf. Migrations of the Loop Current would exercise control over regional hurricane activity by changing the thermal structure of the upper ocean and influencing the role of storm-induced upwelling on hurricane intensification. Other factors that influenced regional and Atlantic basin-wide hurricane activity include the El Niño/Southern Oscillation and the position of the Inter-Tropical Convergence Zone. Many authors have suggested that bicentennial and millennial-scale climate variability may have been driven ultimately by changes in solar irradiance. Thus, low-frequency variability in Atlantic hurricane activity may be an expression of the climate system's response to exogenous forcing.

  16. The United States and the Arab Gulf Monarchies

    International Nuclear Information System (INIS)

    The United States has enduring strategic interests in the Persian Gulf region. To understand these interests and the Usa policy towards the Arab Gulf Monarchies, the french institute of international relations (IFRI) proposes this document. The following chapters are detailed: the United States and the Arab Gulf Monarchies, overview, Chief Unites States Objective: Access to oil, re-evaluating United States Foreign Policy in the Gulf, the second term (Usa strategy). (A.L.B.)

  17. Evidence for deep-water evaporite deposition in the Miocene Kareem Formation, Gemsa basin, eastern Egypt

    Energy Technology Data Exchange (ETDEWEB)

    May, J.A.; Stonecipher, S.A.; Steinmetz, J.C. (Marathon Oil Co., Littleton, CO (United States)); Dyess, J.N. (Marathon Petroleum Egypt, Maadi (Egypt))

    1991-03-01

    The correct interpretation of intercalated Miocene siliciclastics and evaporites of Gemsa basin is crucial for understanding early rift tectonics of the Gulf of Suez, pinpointing the timing of isolation of the Gulf from the Mediterranean, and developing exploration plays. Evaporites of the Kareem Formation comprise celestites and massive, 'chicken-wire,' and laminated anhydrites. Although previously interpreted as sabkha deposits; sedimentologic, petrographic, and paleontologic analyses indicate these evaporites more likely formed in a submarine setting. Marls that encase the evaporites contain a diverse and abundant assemblage of nannoplankton, planktonic foraminifera, diatoms, pteropods, and fish scales indicative of basinal deposition. Associated turbidites also denote deep-water sedimentation. The paucity of benthic diatoms and foraminifera, plus the presence of unburrowed shales, phosphate nodules, early ferroan carbonate cements, and authigenic pyrite, suggest periodic anoxic, or at least disaerobic, bottom waters. These sequences probably represent partial isolation of the Gulf of Suez by middle Miocene, producing periodic basin restriction and evaporative drawdown. Episodes of increasing salinity likely caused the progressive decreases in foram abundance and diversity in marls beneath the anhydrites, culminating in subaqueous evaporite formation. Diverse, indigenous nannoplankton assemblages from shale seams within the anhydrites suggest Gemsa basin was stratified; shallow open-marine conditions coexisted with anhydrite crystallization from deeper hypersaline waters.

  18. Diseño y aplicación de ambiente virtual de aprendizaje en el proceso de enseñanza - aprendizaje de la física en el grado décimo de la I.E. Alfonso López Pumarejo de la ciudad de Palmira

    OpenAIRE

    Rico González, Carlos Arturo

    2011-01-01

    La enseñanza de la asignatura de física en la Institución Educativa Alfonso López Pumarejo (IEALP) se ha caracterizado por el uso del tablero y marcador como únicos recursos didácticos, esta situación ha contribuido a la desmotivación y desinterés por parte de los estudiantes frente a su proceso de aprendizaje. El presente proyecto generó una serie de herramientas didácticas basadas en la incorporación de las Tecnologías de la Información y la Comunicación (TIC) a través de la creación de un ...

  19. Seismic images of the base of the gas hydrate stability zone in Northwest walker ridge, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, D.R. [Fugro GeoServices, Inc (United States); Kendall, B.A. [Oil and Gas Development Corp., Kerr-McGee, Islamabad (Pakistan)

    2002-10-01

    The gas hydrate stability zone, the zone below the sea-floor where gas and water should form gas hydrate is predicted to be present in shallow sediments in deep-water areas around the world, including the deep-water Gulf of Mexico. Few, if any, bottom simulating reflectors (BSR) or other manifestations of the gas hydrate stability zone have been interpreted in the Gulf of Mexico. We show convincing images of the base of the gas hydrate stability zone extracted from exploration 3-D data in Northwest Walker Ridge in the Gulf of Mexico. This area is on the margin of an uplifted and compressed mini-basin and in the vicinity of numerous giant gas mounds at the sea-floor. Shallow stratigraphy includes laterally extensive, steeply dipping basin floor silts and silty sands. This paper shows images of hydrate-trapped gas at multiple reflectors at depths that are coincident with the predicted base of the hydrate stability zone if modeled with a geothermal gradient of 19.6{+-}0.5 deg C/km. A BSR is seen in the seismic data in vertical section, but the more convincing images of the base of gas hydrate stability are seen in map view. (authors)

  20. Sea-level and environmental changes since the last interglacial in the Gulf of Carpentaria, Australia: an overview

    Science.gov (United States)

    Chivas, Allan R.; Garcı́a, Adriana; van der Kaars, Sander; Couapel, Martine; Holt, Sabine; Reeves, Jessica M.; Wheeler, David J.; Switzer, Adam D.; Murray-Wallace, Colin V.; Banerjee, Debabrata; Price, David M.; Wang, Sue X.; Pearson, Grant; Edgar, N. Terry; Beaufort, Luc; de Deckker, Patrick; Lawson, Ewan; Cecil, C. Blaine

    2001-01-01

    The Gulf of Carpentaria is an epicontinental sea (maximum depth 70 m) between Australia and New Guinea, bordered to the east by Torres Strait (currently 12 m deep) and to the west by the Arafura Sill (53 m below present sea level). Throughout the Quaternary, during times of low sea-level, the Gulf was separated from the open waters of the Indian and Pacific Oceans, forming Lake Carpentaria, an isolation basin, perched above contemporaneous sea-level with outlet channels to the Arafura Sea. A preliminary interpretation is presented of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria. The longest core (approx. 15 m) spans the past 130 ka and includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 ka when sea-level repeatedly breached and withdrew from Gulf/Lake Carpentaria. Evidence from biotic remains (foraminifers, ostracods, pollen), sedimentology and geochemistry clearly identifies a final marine transgression at about 9.7 ka (radiocarbon years). Before this transgression, Lake Carpentaria was surrounded by grassland, was near full, and may have had a surface area approaching 600 km×300 km and a depth of about 15 m. The earlier rise in sea-level which accompanied the Marine Isotopic Stage 6/5 transgression at about 130 ka is constrained by sedimentological and biotic evidence and dated by optical- and thermoluminescence and amino acid racemisation methods.

  1. Coastal vulnerability assessment of the Northern Gulf of Mexico to sea-level rise and coastal change

    Science.gov (United States)

    2010-01-01

    A coastal vulnerability index (CVI) was used to map the relative vulnerability of the coast to future sea-level rise along the Northern Gulf of Mexico from Galveston, TX, to Panama City, FL. The CVI ranks the following in terms of their physical contribution to sea-level rise-related coastal change: geomorphology, regional coastal slope, rate of relative sea-level rise, historical shoreline change rate, mean tidal range, and mean significant wave height. The rankings for each variable are combined and an index value is calculated for 1-kilometer grid cells along the coast. The CVI highlights those regions where the physical effects of sea-level rise might be the greatest. The CVI assessment presented here builds on an earlier assessment conducted for the Gulf of Mexico. Recent higher resolution shoreline change, land loss, elevation, and subsidence data provide the foundation for a better assessment for the Northern Gulf of Mexico. The areas along the Northern Gulf of Mexico that are likely to be most vulnerable to sea-level rise are parts of the Louisiana Chenier Plain, Teche-Vermillion Basin, and the Mississippi barrier islands, as well as most of the Terrebonne and Barataria Bay region and the Chandeleur Islands. These very high vulnerability areas have the highest rates of relative sea-level rise and the highest rates of shoreline change or land area loss. The information provided by coastal vulnerability assessments can be used in long-term coastal management and policy decision making.

  2. Gulf Canada Resources Limited 1998 annual report

    International Nuclear Information System (INIS)

    A review of operations in 1998 and financial information from Gulf Canada Resources Limited is provided to keep shareholders abreast of company performance. Gulf Canada Resources Limited explores for, develops, produces and markets conventional and synthetic crude oil, natural gas and natural gas liquids. In 1998, the company's main operating centres were in western Canada (where it owns a nine per cent interest in the Syncrude Joint Venture), Indonesia, the North Sea and Australia. The report summarizes the company's energy resource activities, presents a detailed review of operations, and provides consolidated financial statements, and common share information. Although Gulf Canada Resources sold $ 1.2 billion worth of non-producing assets during the year, year end proved reserves of 838 million barrels of oil equivalent were less than ten per cent lower than a year earlier, reflecting reserve additions of 100 million barrels of oil equivalent. tabs., figs

  3. Deep Eddies in the Gulf of Mexico

    Science.gov (United States)

    Furey, H. H.; Bower, A. S.; Perez-Brunius, P.; Hamilton, P.

    2014-12-01

    A major Lagrangian program is currently underway to map the deep (1500-2500 m) circulation of the entire Gulf of Mexico. Beginning in 2011, more than 120 acoustically tracked RAFOS floats have been released in the eastern, central and western Gulf, many in pairs and triplets. Most floats are programmed to drift for two years, obtaining position fixes and temperature/pressure measurements three times daily. More than 80 floats have completed their missions, and results from the trajectories will be described with a focus on mesoscale eddying behavior. In particular, the first-ever observations of deep energetic anticyclonic eddies (possibly lenses) forming at and separating from a northeastward-flowing boundary current west of Campeche Bank will be discussed. The existence of these eddies has major implications for exchange between the continental slope and interior Gulf. The project is being supported by the U.S. Bureau of Ocean Energy Management (BOEM).

  4. Symptom Patterns Among Gulf War Registry Veterans

    Science.gov (United States)

    Hallman, William K.; Kipen, Howard M.; Diefenbach, Michael; Boyd, Kendal; Kang, Han; Leventhal, Howard; Wartenberg, Daniel

    2003-01-01

    Objectives. We identify symptom patterns among veterans who believe they suffer from Gulf War–related illnesses and characterize groups of individuals with similar patterns. Methods. A mail survey was completed by 1161 veterans drawn from the Gulf War Health Registry. Results. An exploratory factor analysis revealed 4 symptom factors. A K-means cluster analysis revealed 2 groups: (1) veterans reporting good health and few moderate/severe symptoms, and (2) veterans reporting fair/poor health and endorsing an average of 37 symptoms, 75% as moderate/severe. Those in Cluster 2 were more likely to report having 1 or more of 24 medical conditions. Conclusions. These findings are consistent with previous investigations of symptom patterns in Gulf War veterans. This multisymptom illness may be more fully characterized by the extent, breadth, and severity of symptoms reported. PMID:12660208

  5. A High Resolution Geophysical Study of the Offshore Western Gulf of Corinth Rift

    Science.gov (United States)

    McNeill, L.; Cotterill, C.; Stefatos, A.; Henstock, T.; Bull, J.; Collier, R.; Papatheodorou, G.; Georgiopoulou, A.; Ferentinos, G.

    2003-12-01

    The western Gulf of Corinth has generated recent debate in terms of distribution of extensional strain, interactions between active faults and fault geometry. Onshore data suggest that faults do not accommodate extensional strain of the magnitude suggested by geodetic measurements. Recently acquired high resolution geophysical data in the western Gulf of Corinth, including Reson Seabat 8160 50 kHz multibeam bathymetry (with sidescan collected simultaneously) and sparker and boomer seismic profiles, will allow a detailed study of faulting relationships, fault propagation history and associated sedimentological processes. Multibeam data indicate the complex axial and tributary channel pattern of the gulf as well as revealing the surface expression of active faults on both margins and within the basin centre. Several fault tips are evident, including the Aigion fault which has been surveyed in great detail with boomer lines spaced between 25-100 m. The fault tip is complex with multiple synthetic and antithetic splays. The post-lowstand transgressive surface is clearly imaged and therefore fault growth rates can be established. Gas-related features are common, including pockmarks and mud volcanoes. To the east, displacement on the eastern tip of the Eliki fault decreases rapidly offshore and a splay of the Derveni fault is observed. A major S-dipping antithetic fault opposite the Eastern Eliki fault has clear bathymetric expression and is locally associated with a prominent basement ridge. This fault may make a significant contribution to extensional strain in this part of the rift. In the centre of the basin, sediments are deformed by multiple minor faults with seafloor displacement. Ultimately, high resolution offshore interpretations can be integrated with regional datasets and existing data (e.g., geomorphic, paleoseismological and sedimentological) onshore and used to better assess rift deformation models, rift evolution and local seismic hazards.

  6. Generation of Wind Waves in the Persian Gulf: A Numerical Investigation

    Science.gov (United States)

    Liao, Y.; Kaihatu, J. M.

    2010-12-01

    The Persian Gulf is a long shallow basin located between the Arabian Peninsula and Iran. Wind-wave generation processes in the region are often affected by the shamal, a strong wind caused by the passage of cold fronts over the mountains of Turkey and Kurdistan. This can set up sudden energetic wind seas, hampering marine traffic. It is not immediately clear whether present wind-wave models can predict this intense, short-term growth and evolution under these conditions. Furthermore, few wave measurements or models studies have been performed in this area. In advance of a wind-wave generation experiment to be conducted off the Qatar coast, we performed a climatological study of the wind wave environment in the Persian Gulf. Using the SWAN wave model as a baseline of the state of the art, five years (2004-2008)of wind field model hindcasts from COAMPS are used as forcing.To investigate the sensitivity of the results to bathymetry, the climatological analysis was run twice more, with refraction or wave breaking deactivated, in turn. The results do not show significant differences with and without refraction, which implies the wind-wave process in Persian Gulf is less dominated by the variation of bathymetry. However the results show that a large amount of wave is dissipated by wave breaking. Wide, flat and shallow bathymetry in Persian Gulf results in a long-fetch scenario, particularly for waves arriving from the northwest. It implies that long period wind-generated waves can be fully generated in this region. Wave height is therefore fully grown by the long-fetch condition, so as to lead in higher possibility of wave breaking and energy dissipation.

  7. Gulf International Conference on Applied Mathematics 2013

    CERN Document Server

    Advances in Applied Mathematics

    2014-01-01

    This volume contains contributions from the Gulf International Conference in Applied Mathematics, held at the Gulf University for Science & Technology. The proceedings reflects the three major themes of the conference. The first of these was mathematical biology, including a keynote address by Professor Philip Maini. The second theme was computational science/numerical analysis, including a keynote address by Professor Grigorii Shishkin. The conference also addressed more general applications topics, with papers in business applications, fluid mechanics, optimization, scheduling problems, and engineering applications, as well as a keynote by Professor Ali Nayfeh.

  8. Star Formation in the Gulf of Mexico

    CERN Document Server

    Armond, Tina; Bally, John; Aspin, Colin

    2011-01-01

    We present an optical/infrared study of the dense molecular cloud, L935, dubbed "The Gulf of Mexico", which separates the North America and the Pelican nebulae, and we demonstrate that this area is a very active star forming region. A wide-field imaging study with interference filters has revealed 35 new Herbig-Haro objects in the Gulf of Mexico. A grism survey has identified 41 Halpha emission-line stars, 30 of them new. A small cluster of partly embedded pre-main sequence stars is located around the known LkHalpha 185-189 group of stars, which includes the recently erupting FUor HBC 722.

  9. Gulf Coast Clean Energy Application Center

    Energy Technology Data Exchange (ETDEWEB)

    Dillingham, Gavin

    2013-09-30

    The Gulf Coast Clean Energy Application Center was initiated to significantly improve market and regulatory conditions for the implementation of combined heat and power technologies. The GC CEAC was responsible for the development of CHP in Texas, Louisiana and Oklahoma. Through this program we employed a variety of outreach and education techniques, developed and deployed assessment tools and conducted market assessments. These efforts resulted in the growth of the combined heat and power market in the Gulf Coast region with a realization of more efficient energy generation, reduced emissions and a more resilient infrastructure. Specific t research, we did not formally investigate any techniques with any formal research design or methodology.

  10. Intrinsic low-frequency variability of the Gulf Stream

    Directory of Open Access Journals (Sweden)

    G. Quattrocchi

    2012-03-01

    Full Text Available In this paper a process study aimed at analyzing the low-frequency variability of intrinsically oceanic origin of the Gulf Stream (GS and GS extension (GSE is presented. An eddy-permitting reduced-gravity nonlinear shallow water model is implemented in an idealized North Atlantic Ocean, with schematic boundaries including the essential geometric features of the coastline and a realistic zonal basin width at all latitudes. The forcing is provided by a time-independent climatological surface wind stress obtained from 41 years of monthly ECMWF fields. The model response yields strong intrinsic low-frequency fluctuations on the interannual to decadal time scales. The modelled time-averaged GS/GSE flows are found to exhibit several features that can also be deduced from satellite altimeter data, such as the Florida Current seaward deflection, the GS separation at Cape Hatteras, and the overall structure of the GSE. The intrinsic low-frequency variability yields two preferred states of the GSE differing in latitudinal location that also have their counterpart in the altimeter data. A preliminary analysis of the variability in terms of dynamical systems theory is carried out by using the lateral eddy viscosity as the control parameter. A complex transition sequence from a steady state to irregular low-frequency variability emerges, in which Hopf and global bifurcations can be identified.

  11. Formation of Continental Fragments: The Tamayo Bank, Gulf of California

    Science.gov (United States)

    van Wijk, J.; Abera, R.; Axen, G. J.

    2015-12-01

    Potential field data are used to construct a two-dimensional crustal model along a profile through the Tamayo Trough and Bank in the Gulf of California. The model is constrained by seismic reflection and refraction data, and field observations. The potential field data do not fit a model where the crust of the Tamayo trough is continental, but they fit well with a model where the Tamayo trough crust is oceanic. This implies that the Tamayo Bank is entirely bounded by oceanic crust and is a microcontinent. The oceanic crust of the Tamayo trough that separates the Tamayo Bank from the mainland of Mexico is thin (~4 km), so oceanic spreading was probably magma-starved before it ceased. This led us to come up with a model that explains the formation of microcontinents that are smaller in size and are not found in the proximity of hotspots. At first, seafloor spreading commences following continental breakup. When the magma supply to the ridge slows down, the plate boundary strengthens. Hence, the ridge may be abandoned while tectonic extension begins elsewhere, or slow spreading may continue while a new ridge starts to develop. The old spreading ridge becomes extinct. An asymmetric ocean basin forms if the ridge jumps within oceanic lithosphere; a microcontinent forms if the ridge jumps into a continental margin. This model for formation of continental fragments is applicable to other regions as well, eliminating the need of mantle plume impingement to facilitate rifting of a young continental margin and microcontinent formation.

  12. Reconstruction of the Gulf of Lions margin during the Messinian Salinity Crisis

    Science.gov (United States)

    Steckler, M. S.; Lofi, J.; Mountain, G. S.; Ryan, W. B. F.; Berné, S.; Gorini, C.

    2003-04-01

    The desiccation of the Mediterranean Sea during the Messinian Salinity Crisis from 5.9 to 5.3 Ma subaerially exposed its continental margins. In regions near major rivers, the margins were eroded into dissected subaerial ramps. Farther seaward, the deep Mediterranean basin received extensive evaporitic deposits along with clastic debris shed from the margins. The fluvial landscape at the former continental margins and the deep evaporite basins were then rapidly resubmerged at by the flooding of the Mediterranean at the end of the crisis. Since that time, rivers have fed a continuous supply of sediment, rebuilt the margins and buried the erosion surface and Messinian sediments. The geometry of the Messinian erosion surfaces and strata has been progressively deformed by subsidence, compaction, sediment loading and tectonics. Seismic reflection profiles show a large sag in the Messinian erosion surface beneath the Gulf of Lions margin that was clearly not present at 5.3 Ma. This geometry highlights the need to reconstruct the past bathymetry and stratigraphy. In order to address this problem, we have performed preliminary 2D backstripping of several profiles constructed from a TotalFinaElf MCS survey on the shelf and the CALMAR project survey farther offshore. Our reconstructions provide estimates of the geometry of the margin during the Salinity Crisis and support a two-stage model for the desiccation of the Western Mediterranean. During the first stage the Western Mediterranean was drawn down to the depth of a sill separating the Eastern and Western basins; during the second phase the Western basin was fully desiccated and the upper salt was deposited. Our reconstructions indicate the presence of two erosion surfaces that correspond to these two phases. We have used river thalwegs in the reconstructed profiles to define the incised lower erosion surface as a concave up surface that averages ˜0.6^o dip and ends at the evaporites at a depth of 1800--1900 m. The first

  13. EXPORTACIÓN DE SEDIMENTOS DESDE CUENCAS HIDROGRÁFICAS DE LA VERTIENTE ORIENTAL DEL GOLFO DE URABÁ: INFLUENCIAS CLIMÁTICAS Y ANTRÓPICAS SEDIMENT EXPORTS FROM THE EASTERN BASIN IN THE GULF OF URABA: CLIMATIC AND ANTHROPOGENIC INFLUENCES

    Directory of Open Access Journals (Sweden)

    Andrea Arroyave-Rincón

    2012-06-01

    Full Text Available En este artículo se analizaron series de tiempo mensuales de precipitación (mm, caudal (m³/s y exportación de sedimentos (kton/día en cuencas de la vertiente oriental del golfo de Urabá. Se analizó la dinámica de la exportación de sedimentos, la relación caudal-exportación y caudal-precipitación. Se infirió el papel de fenómenos atmosféricos estacionales y multianuales (El Niño-Oscilación Sureña, ENOS, y factores antrópicos. Se encontraron variabilidades intra-anuales significativas (ANOVA: pThis article reports on a time-series analysis of monthly precipitation (mm, river discharge (m³/s and sediment export (kton/day in Urabá Gulf. We analyzed the dynamics of sediment exports relative to river discharge, and the dynamics of this latter variable relative to precipitation. We inferred the role of seasonal and multi-annual atmospheric drivers, and anthropogenic factors. We found significant intra-annual variability (ANOVA: p<0.001 consistent with the movement of the Inter-Tropical Convergence Zone. The Pearson correlation between variables showed direct and significant relationships (p<0.001. The ENSO did not influence precipitation. Using aerial-photographs, we analyzed anthropogenic factors in the municipalities of Apartadó (1961-2005 and Chigorodó (1961-2007, finding up to a 90% forest-cover loss. Using double-mass graphs, it was observed an increase in slope steepness (during mid 90’s, consistent with an increase in sediment export rate relative to discharge, thus suggesting that there was a significant effect of human factors, such as deforestation.

  14. Tides in the Gulf of Kutch, India

    Digital Repository Service at National Institute of Oceanography (India)

    Shetye, S.R.

    cause for ampli"cation of the M 2 and S 2 is quarter wavelength resonance. This assertion is motivated by the fact that the length of the gulf and its average depth are suitably matched to set up near-resonance co-oscillations as envisioned...

  15. New offshore platform in the Mexican Gulf

    Energy Technology Data Exchange (ETDEWEB)

    Beisel, T.

    1982-04-01

    After a construction period of only 10 months, the second steel Offshore platform was recently completed in the Mexican Gulf. The pattern for this structure was the Cognac platform. The erection of the new platform, called the 'Cerveza' platform, is described in the article.

  16. The Gulf Stream and Density of Fluids

    Science.gov (United States)

    Landstrom, Erich

    2006-01-01

    A few kilometers from the shores of Palm Beach County, Florida, is the Gulf Stream current--a remarkable "river" within an ocean. The current's journey across the Atlantic Ocean connects southeast Florida and southwest Great Britain as it streams steadily north at speeds of 97 km a day; moving 100 times as much water as all the rivers on Earth.…

  17. Multiple Currents in the Gulf Stream System

    OpenAIRE

    Fuglister, F. C.

    2011-01-01

    A new interpretation of the accumulated temperature and salinity data from the Gulf Stream Area indicates that the System is made up of a series of overlapping currents. These currents are separated by relatively weak countercurrents. Data from a recent survey are presented as supporting this hypothesis.DOI: 10.1111/j.2153-3490.1951.tb00804.x

  18. The Gulf Stream: Inertia and friction

    OpenAIRE

    ASSAF, GAD

    2011-01-01

    The inertial theory of the Gulf Stream (Charney, 1955) is extended to include vertical friction in the cyclonic shear zone (the western side) of the stream. The vertical friction is assumed to be controlled by local Froude conditions.DOI: 10.1111/j.2153-3490.1977.tb00717.x

  19. 77 FR 56749 - Gulf Coast Ecosystem Restoration

    Science.gov (United States)

    2012-09-13

    ... plan for addressing ecological concerns in the Gulf of Mexico. In light of the release of the Strategy..., including section 311 of the Federal Water Pollution Control Act (FWPCA) (33 U.S.C. 1321), section 1006 of the Oil Pollution Act of 1990 (33 U.S.C. 2706), and section 301 of title 3, United States Code, it...

  20. Fishery potential of the Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Govindan, K.; Ramaiah, Neelam; Gajbhiye, S.N.

    /h) was three times more productive than the creek (av. 2.3 kg/h). The number of species found in the Gulf and creek were respectively 34 and 20 suggesting good biodiversity of the living resources of the area....

  1. Rickettsiae in Gulf Coast Ticks, Arkansas, USA

    OpenAIRE

    Trout, Rebecca; Steelman, C Dayton; Szalanski, Allen L.; Williamson, Phillip C

    2010-01-01

    To determine the cause of spotted fever cases in the southern United States, we screened Gulf Coast ticks (Amblyomma maculatum) collected in Arkansas for rickettsiae. Of the screened ticks, 30% had PCR amplicons consistent with Rickettsia parkeri or Candidatus Rickettsia amblyommii.

  2. Prospects for Gulf Region with closed greenhouse

    NARCIS (Netherlands)

    Campen, J.B.

    2009-01-01

    In countries such as Saudi Arabia and the United Arab Emirates, water is scarce as rainfall is minimal. Growers in the Gulf Region rely on groundwater for evaporative cooling and irrigation. This source of water is running out and growers are deciding to end production. The governments of the Kingdo

  3. Sediment transport and fan deposition in the Gulf of Alaska: Effects of transform motion on deep sea sedimentation

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, A.J.; Bruns, T.R.; Carlson, P.R. (Geological Survey, Palo Alto, CA (USA)); Dobson, M.R. (Univ. of College of Wales, Aberystwyth (Wales))

    1990-06-01

    GLORIA side-scan sonar images and two channel seismic profiles recently collected in the Gulf of Alaska reveal a major site of late Miocene to Recent terrigenous sediment accumulation on the oceanic plate adjacent to the Fairweather-Queen Charlotte transform and the Yakutat Terrane. Sediment moving across this margin has formed several large channel dominated fan systems that blanket the entire gulf and spill westward onto the Tufts Abyssal Plain. The Surveyor Fan, fed by the glaciers of the Yakutat Terrane and insulated from transform sediment source offset by the Terrane, has maintained a single channel course over the entire life of the fan. The Chirikov and Baranof fans receive their sediment supply from glaciofluvial point sources along the SE Alaska margin, separated from the fans by an active transform. The fans show a southward younging of channel ages consistent with the sense of plate motion. Early (late Miocene) deposition within the gulf was limited to the structural basin between the continental margin and the Kodiak-Bowie seamount chain. The geometry of these early depositional systems is poorly known, but available data suggest their channels were oriented NW-SE. Subsequent establishment of a depositional slope between the margin and the seamount chain, coupled with the filling of the basin, led to a reorganization into SW-NE channel systems. The fan bodies of the Gulf of Alaska are members of a distinct class of fans that are characterized by long distributary channels which persist to near the fan limits. This type of fan morphology is most often attributed to a predominantly fine-grained sediment supply. This is difficult to reconcile with the obvious proximal glacial source for much of the sediment supplied to these fans.

  4. Integration of numerical modeling and observations for the Gulf of Naples monitoring network

    Science.gov (United States)

    Iermano, I.; Uttieri, M.; Zambianchi, E.; Buonocore, B.; Cianelli, D.; Falco, P.; Zambardino, G.

    2012-04-01

    Lethal effects of mineral oils on fragile marine and coastal ecosystems are now well known. Risks and damages caused by a maritime accident can be reduced with the help of better forecasts and efficient monitoring systems. The MED project TOSCA (Tracking Oil Spills and Coastal Awareness Network), which gathers 13 partners from 4 Mediterranean countries, has been designed to help create a better response system to maritime accidents. Through the construction of an observational network, based on state of the art technology (HF radars and drifters), TOSCA provides real-time observations and forecasts of the Mediterranean coastal marine environmental conditions. The system is installed and assessed in five test sites on the coastal areas of oil spill outlets (Eastern Mediterranean) and on high traffic areas (Western Mediterranean). The Gulf of Naples, a small semi-closed basin opening to the Tyrrhenian Sea is one of the five test-sites. It is of particular interest from both the environmental point of view, due to peculiar ecosystem properties in the area, and because it sustains important touristic and commercial activities. Currently the Gulf of Naples monitoring network is represented by five automatic weather stations distributed along the coasts of the Gulf, one weather radar, two tide gauges, one waverider buoy, and moored physical, chemical and bio-optical instrumentation. In addition, a CODAR-SeaSonde HF coastal radar system composed of three antennas is located in Portici, Massa Lubrense and Castellammare. The system provides hourly data of surface currents over the entire Gulf with a 1km spatial resolution. A numerical modeling implementation based on Regional Ocean Modeling System (ROMS) is actually integrated in the Gulf of Naples monitoring network. ROMS is a 3-D, free-surface, hydrostatic, primitive equation, finite difference ocean model. In our configuration, the model has high horizontal resolution (250m), and 30 sigma levels in the vertical. Thanks

  5. Messinian paleoenvironmental evolution in the lower Guadalquivir Basin (SW Spain) based on benthic foraminifera.

    OpenAIRE

    Pérez-Asensio, J.N.; Aguirre, J.; Schmiedl, G.; Civis Llovera, J.

    2012-01-01

    Benthic foraminiferal assemblages of a drill core from the lower Guadalquivir Basin (northern Gulf of Cádiz, SW Spain) have been analyzed in order to reconstruct the paleoenvironmental evolution in the vicinity of the Betic seaways during the Messinian. The core consists of marine sediments ranging from the latest Tortonian to the early Pliocene. Changes in the abundance of certain marker species, planktonic/benthic ratio (P/B ratio), paleodepth estimated with a transfer function, content of ...

  6. Flow-Through, Low Retention Hydrocarbon Generation in Active Sedimentary Basins

    Science.gov (United States)

    Cathles, L. M.

    2002-12-01

    Hydrocarbons are typically generated when thin (consumption of oil to date, from a 100 x 200 km portion of one basin in a relatively short timespan (about 20 Ma) provides an interesting geologic context for human production and consumption. The rapid venting also has potentially important implications for the fisheries food chain in the northern Gulf of Mexico. The venting rate is fast enough that hydrocarbons could be a significant aquatic food source.

  7. The progress in knowledge of physical oceanography of the Gulf of Finland: a review for 1997-2007

    Directory of Open Access Journals (Sweden)

    Tarmo Soomere

    2008-09-01

    Full Text Available The main findings of studies of the physical oceanography of the Gulf of Finland (GoF during 1997-2007 are reviewed. The aim is to discuss relevant updates published in international peer-reviewed research papers and monographs, bearing in mind that a comprehensive overview of the studies up to the mid-1990s is available (Alenius et al. 1998. We start the discussion with updates on the basic hydrographical and stratification conditions, and progress in the understanding of atmospheric forcing and air-sea interaction. Advances in the knowledge of basin-scale and mesoscale dynamics are summarised next. Progress in circulation and water exchange dynamics has been achieved mostly by means of numerical studies. While the basic properties of circulation patterns in the gulf have been known for a century, new characteristics and tools such as water age, renewal index, and high-resolution simulations have substantially enriched our knowledge of processes in the Gulf of Finland during the last decade. We present the first overview of both status and advances in optical studies in this area. Awareness in this discipline has been significantly improved as a result of in situ measurements. Our understanding of the short- and long-term behaviour of the sea level as well as knowledge of the properties of both naturally and anthropogenically induced surface waves have expanded considerably during these ten years. Developments in understanding the ice conditions of the Gulf of Finland complete the overview, together with a short discussion of the gulf's future, including the response to climate change. Suggestions for future work are outlined.

  8. The Mimallonidae (Lepidoptera, Mimallonoidea) of the Caribbean Basin, with the descriptions of two new species.

    Science.gov (United States)

    Laurent, Ryan A St; Mccabe, Timothy L

    2016-01-01

    Mimallonidae of the Caribbean Basin are discussed, with attention primarily given to species endemic to the Caribbean islands and the northern coast of Venezuela. The Caribbean Basin is a political term for tropical regions circumscribed by the Gulf of Mexico. Cicinnus bahamensis sp. n. is described from the Bahamas, the first species of Mimallonidae from this country. The Cuban species Cicinnus packardii (Grote, 1865), the closest relative of C. bahamensis sp. n., is figured and compared. A third, similar, species from northern coastal Venezuela, C. falcoargenteus sp. n., is described and compared to the previous two species. PMID:27394281

  9. Rationale, design, methodology and hospital characteristics of the first gulf acute heart failure registry (gulf care

    Directory of Open Access Journals (Sweden)

    Kadhim J Sulaiman

    2014-01-01

    Full Text Available Background: There is paucity of data on heart failure (HF in the Gulf Middle East. The present paper describes the rationale, design, methodology and hospital characteristics of the first Gulf acute heart failure registry (Gulf CARE. Materials and Methods: Gulf CARE is a prospective, multicenter, multinational registry of patients >18 year of age admitted with diagnosis of acute HF (AHF. The data collected included demographics, clinical characteristics, etiology, precipitating factors, management and outcomes of patients admitted with AHF. In addition, data about hospital readmission rates, procedures and mortality at 3 months and 1-year follow-up were recorded. Hospital characteristics and care provider details were collected. Data were entered in a dedicated website using an electronic case record form. Results: A total of 5005 consecutive patients were enrolled from February 14, 2012 to November 13, 2012. Forty-seven hospitals in 7 Gulf States (Oman, Saudi Arabia, Yemen, Kuwait, United Gulf Emirates, Qatar and Bahrain participated in the project. The majority of hospitals were community hospitals (46%; 22/47 followed by non-University teaching (32%; 15/47 and University hospitals (17%. Most of the hospitals had intensive or coronary care unit facilities (93%; 44/47 with 59% (28/47 having catheterization laboratory facilities. However, only 29% (14/47 had a dedicated HF clinic facility. Most patients (71% were cared for by a cardiologist. Conclusions: Gulf CARE is the first prospective registry of AHF in the Middle East, intending to provide a unique insight into the demographics, etiology, management and outcomes of AHF in the Middle East. HF management in the Middle East is predominantly provided by cardiologists. The data obtained from this registry will help the local clinicians to identify the deficiencies in HF management as well as provide a platform to implement evidence based preventive and treatment strategies to reduce the burden

  10. 78 FR 6404 - Agency Information Collection (Survey of Chronic Gastrointestinal Illness in Persian Gulf...

    Science.gov (United States)

    2013-01-30

    ... AFFAIRS Agency Information Collection (Survey of Chronic Gastrointestinal Illness in Persian Gulf Veterans....'' SUPPLEMENTAL INFORMATION: Titles: a. Survey of Chronic Gastrointestinal Illness in Persian Gulf Veterans, VA... Persian Gulf War returned with persistent gastrointestinal symptoms, typical of...

  11. Gulf of Mexico circulation within a high-resolution numerical simulation of the North Atlantic Ocean

    Science.gov (United States)

    Romanou, Anastasia; Chassignet, Eric P.; Sturges, Wilton

    2004-01-01

    The Gulf of Mexico circulation is examined from the results of a high-resolution (1/12°) North Atlantic simulation using the Miami Isopycnic Coordinate Ocean Model. The motivation for this paper is twofold: first, we validate the model's performance in the Gulf of Mexico by comparing the model fields to past and recent observations, and second, given the good agreement with the observed Gulf of Mexico surface circulation and Loop Current variability, we expand the discussion and analysis of the model circulation to areas that have not been extensively observed/analyzed, such as the vertical structure of the Loop Current and associated eddies, especially the deep circulation below 1500 m. The interval between successive model eddy sheddings is 3 to 15 months, the eddy diameters range between 140 and 500 km, the life span is about 1 year, and the translational speeds are 2-3 km d-1, in good agreement with observations. Areas of high cyclonic eddy occurrence in the model are southwest of Florida, the Loop Current boundary, and the western Campeche Bay area. The cyclonic eddy diameters range between 50 and 375 km, the orbital speeds range between 1 and 55 cm s-1, the translational speeds range between 0.5 and 14 km d-1, and the eddy life spans range between 1 and 3 months. The vertical structure of the temperature and salinity of each modeled eddy, from the moment it is shed until it disintegrates in the western Gulf of Mexico, is in agreement with the few available observations. Below 1500 m, deep cyclonic eddies are associated with the surface Loop Current anticyclones. The eddy variability is consistent with Rossby waves propagating westward, and there is bottom intensification of the flow close to steep topography. Overall, we show that this very high horizontal resolution isopycnic coordinate ocean model, which is able to produce a quite realistic surface circulation for the North and equatorial Atlantic, is also able to reproduce well the smaller-scale, basin

  12. Mid- to Late Holocene Climate Shift in the Southern Gulf of California and Tropical Pacific Ocean

    Science.gov (United States)

    Perez-Cruz, L. L.; Fucugauchi, J. U.; Velasco, V.; Rodriguez, A.; Choumiline, K.

    2014-12-01

    A multiproxy record has been acquired from a gravity core (DIPAL-I K47) taken in La Paz Basin, an area which is situated in the southwestern sector of the Gulf of California at the junction to the Tropical Pacific Ocean. The high-resolution data sets, from XRF, TOC, magnetic susceptibility and hysteresis measurements, were used to track climatic changes in the tropical climate system at sub-centennial time scales over the past 7.3 cal kyr BP. The paleoprecipitation record shows variation trends, with a shift during the mid- to late Holocene, characterized by changes from high to low humidity. Pluvial, biogenic and eolian input, marked by variations in Ti, Si, Fe, K, Ca, Zr/Ti, Ca/Ti and magnetic susceptibility, shows trend changes between 7-5 cal kyr, 5-4.5 cal kyr, 4.5-3.5 cal kyr and 2.15-1.4 kyr. Drought events are recognized from 3.7 to 3.4, 2.8 to 1.8 cal kyr BP, and between 1.4 and 1.2 cal kyr BP. The southern Gulf is well suited for documenting the climatic and precipitation changes in the tropical Pacific Ocean associated with ITCZ latitudinal migration, PDO, ENSO events and the North American monsoon. Analysis of sourcing, transport and deposition of sediments is used for reconstructing the changing ocean-atmosphere circulation patterns, particularly sensitive to paleoprecipitation. The Bay receives sediments mainly from the surrounding volcanic ranges of the peninsular Baja California. There are no rivers in the peninsula and sediments are related to pluvial input trough ephemeral creeks along the steep cliff ranges and narrow shelf. Biogenic sediments are associated with productivity and oceanographic conditions through upwellings and mesoscale gyres. Eolian sediments are transported into the basin from the peninsula and continent, including transport of fine dust from the northern desert of Sonora-Mojave and arid terrains in the peninsula. It is important to highlight that a common 1800 yr solar variation spectral periodicity has been captured

  13. A high-resolution hydrodynamic-biogeochemical coupled model of the Gulf of Cadiz – Alboran Sea region.

    Directory of Open Access Journals (Sweden)

    D. M. MACIAS

    2015-01-01

    Full Text Available The southern Iberia regional seas comprise the Gulf of Cadiz and the Alboran Sea sub-basins connected by the narrow Strait of Gibraltar. Both basins are very different in their hydrological and biological characteristics but are, also, tightly connected to each other. Integrative studies of the whole regional oceanic system are scarce and difficult to perform due to the relative large area to cover and the different relevant time-scales of the main forcings in each sub-basin. Here we propose, for the first time, a fully coupled, 3D, hydrodynamic-biogeochemical model that covers, in a single domain (~2km resolution both marine basins for a 20 years simulation (1989-2008. Model performance is assessed against available data in terms of spatial and temporal distributions of biological variables. In general, the proposed model is able to represent the climatological distributions of primary and secondary producers and also the main seasonality of primary production in the different sub-regions of the analyzed basins. Potential causes of the observed mismatches between model and data are identified and some solutions are proposed for future model development. We conclude that most of these mismatches could be attributed to the missing tidal forcing in the actual model configuration. This model is a first step to obtain a meaningful tool to study past and future oceanographic conditions in this important marine region constituting the unique connection of the Mediterranean Sea with the open world’s ocean.

  14. Depleted uranium and the Gulf War syndrome

    International Nuclear Information System (INIS)

    Some military personnel involved in the 1991Gulf War have complained of continuing stress-like symptoms for which no obvious cause has been found. These symptoms have at times been attributed to the use of depleted uranium (DU) in shell casings which are believed to have caused toxic effects. Depleted uranium is natural uranium which is depleted in the rarer U-235 isotope. It is a heavy metal and in common with other heavy metals is chemically toxic. It is also slightly radioactive and could give rise to a radiological hazard if dispersed in finely divided form so that it was inhaled. In response to concerns, the possible effects of DU have been extensively studied along with other possible contributors to Gulf War sickness. This article looks at the results of some of the research that has been done on DU. (author)

  15. Gulf of Mexico Regional Collaborative Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Kathleen S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Judd, Chaeli [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Engel-Cox, Jill A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gulbransen, Thomas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, Michael G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodruff, Dana L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guzy, Michael [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hardin, Danny [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Estes, Maury [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2007-12-01

    This report presents the results of the Gulf of Mexico Regional Collaborative (GoMRC), a year-long project funded by NASA. The GoMRC project was organized around end user outreach activities, a science applications team, and a team for information technology (IT) development. Key outcomes are summarized below for each of these areas. End User Outreach; Successfully engaged federal and state end users in project planning and feedback; With end user input, defined needs and system functional requirements; Conducted demonstration to End User Advisory Committee on July 9, 2007 and presented at Gulf of Mexico Alliance (GOMA) meeting of Habitat Identification committee; Conducted significant engagement of other end user groups, such as the National Estuary Programs (NEP), in the Fall of 2007; Established partnership with SERVIR and Harmful Algal Blooms Observing System (HABSOS) programs and initiated plan to extend HABs monitoring and prediction capabilities to the southern Gulf; Established a science and technology working group with Mexican institutions centered in the State of Veracruz. Key team members include the Federal Commission for the Protection Against Sanitary Risks (COFEPRIS), the Ecological Institute (INECOL) a unit of the National Council for science and technology (CONACYT), the Veracruz Aquarium (NOAA’s first international Coastal Ecology Learning Center) and the State of Veracruz. The Mexican Navy (critical to coastal studies in the Southern Gulf) and other national and regional entities have also been engaged; and Training on use of SERVIR portal planned for Fall 2007 in Veracruz, Mexico Science Applications; Worked with regional scientists to produce conceptual models of submerged aquatic vegetation (SAV) ecosystems; Built a logical framework and tool for ontological modeling of SAV and HABs; Created online guidance for SAV restoration planning; Created model runs which link potential future land use trends, runoff and SAV viability; Analyzed SAV

  16. Natural gamma radionuclides in sediments of Gulf of Mexico: An approach to radio-tracers transport and distribution of sediments in marine environments

    International Nuclear Information System (INIS)

    The following paper contains information of 23 cores collected nuclides in the Gulf of Mexico from 70 to 2,100 meters of depth. The cores were collected in Mexican Gulf of Mexico on OGMEX Oceanographic Campaigns between 1993 and 1995. Radiometric determinations were measured by the Silena gamma-spectrometer from 50 to 60,000 s at the Environmental Laboratory in Cienfuegos, Cuba. A database of 920 natural radio-nuclides from chains of 232Th and 238U, was obtained from 180 samples. The most significant result was the geographic distribution of gamma radionuclides measured concentrations is regionally distinct. Finding a low 238U gamma radio-nuclides concentration at low depth zones and high concentration in depth waters. While the already mentioned conditions are inverted for the 232Th gamma radionuclides. As it is the case of 214Pb and 212Pb. The discussion of results as here presented allows to assume a geographic distribution of natural gamma radionuclides under sedimentary material supplying conditions by the hydrological basins which drain to the Gulf of Mexico and the marine currents transport those materials through the inside of the Gulf of Mexico. Associated results are shown to the rest of Gamma Radionuclides Natural that belong to the 238U and 232Th chains in order to permit corroborating associations in different proportions of these radionuclides in geological material of hydrological basins associated to the western slope in the Gulf of Mexico. In conclusion the work as here presented allows the understanding and elucidation of the origin, transport and, deposition of sedimentary material by means of natural radionuclides tracers using low gamma spectrometry

  17. Natural gamma radionuclides in sediments of the Gulf of Mexico: An approach to radio-tracers transport and distribution of sediments in marine environments

    International Nuclear Information System (INIS)

    The following paper contains information of 23 cores collected nuclides in the Gulf of Mexico from 70 to 2,100 meters of depth. The cores were collected in Mexican Gulf of Mexico on OGMEX Oceanographic Campaigns between 1993 and 1995. Radiometric determinations were measured by the Silena gamma-spectrometer from 50 to 60,000 s at the Environmental Laboratory in Cienfuegos, Cuba. A database of 920 natural radio-nuclides from chains of 232Th and 238U, was obtained from 180 samples. The most significant result was the geographic distribution of gamma radionuclides measured concentrations is regionally distinct. Finding a low 238U gamma radio-nuclides concentration at low depth zones and high concentration in depth waters. While the already mentioned conditions are inverted for the 232Th gamma radionuclides. As it is the case of 214Pb and 212 Pb. The discussion of results as here presented allows to assume a geographic distribution of natural gamma radionuclides under sedimentary material supplying conditions by the hydrological basins which drain to the Gulf of Mexico and the marine currents transport those materials through the inside of the Gulf of Mexico. Associated results are shown to the rest of Gamma Radionuclides Natural that belong to the 238U and 232Th chains in order to permit corroborating associations in different proportions of these radionuclides in geological material of hydrological basins associated to the western slope in the Gulf of Mexico. In conclusion the work as here presented allows the understanding and elucidation of the origin, transport and, deposition of sedimentary material by means of natural radionuclides tracers using low gamma spectrometry

  18. Gulf of Mexico mud toxicity limitations

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, H.E.; Beardmore, D.H. (Phillips Petroleum Co., Bartlesville, OK (USA)); Stewart, W.S. (Drilling Specialties Co. (US))

    1989-10-01

    Because of the Environmental Protection Agency's recent toxicity limits on drilling mud discharges for offshore Gulf of Mexico, Phillips Petroleum conducted a mud toxicity study based on both field and lab tests. The study, discussed in this article, found the polyanionic cellulose-sulfomethylated quebracho-chrome lignosulfonate mud Phillips had been using would comfortably pass the toxicity limitations. The study also found barite and thinners were of low toxicity, and hydrocarbons and surfactants were highly toxic.

  19. Florida, Bahamas, Cuba and Gulf Stream, USA

    Science.gov (United States)

    1992-01-01

    This unique photo offers a view of the Florida peninsula, western Bahamas, north central Cuba and the deep blue waters of the Gulf Stream, that hugs the east coast of Florida (27.0N, 82.0W). In addition to being an excellent photograph for showing the geographical relationships between the variety of landforms in this scene, the typical effect of the land-sea breeze is very much in evidence as few clouds over water, cumulus build up over landmass.

  20. Q&A on Beibu Gulf

    Institute of Scientific and Technical Information of China (English)

    Alice

    2010-01-01

    China-ASEAN FTA, the world's largest free trade area in terms of population took effect on January 1, 2010, covering 13 million square kilometers and 1.9 billion people. Over 90 percent of the commodities traded between China and the six original ASEAN countries, including Brunei, Indonesia, Malaysia, the Philippines, Singapore and Thailand, now enjoy no tariffs from 2010. As a window to ASEAN countries, Beibu Gulf Economic Zone is in more limelight since the new year.

  1. Upwelling in the Gulf of Lions

    OpenAIRE

    Millot, Claude; Wald, Lucien

    1981-01-01

    International audience The hydrological and meteorological characteristics of the Gulf of Lions are such that upwelling occurs with no bias due to tides or strong longshore circulation. The sky is generally cloud-free, an uncommon feature in an upwelling area that allows extensive use of satellite infrared data. The observations are adequate to compute mean maps of the sea-surface temperature during upwelling events. Undoubtedly upwelling is much more intense along straitght coastal segmen...

  2. NASA Gulf of Mexico Initiative Hypoxia Research

    Science.gov (United States)

    Armstrong, Curtis D.

    2012-01-01

    The Applied Science & Technology Project Office at Stennis Space Center (SSC) manages NASA's Gulf of Mexico Initiative (GOMI). Addressing short-term crises and long-term issues, GOMI participants seek to understand the environment using remote sensing, in-situ observations, laboratory analyses, field observations and computational models. New capabilities are transferred to end-users to help them make informed decisions. Some GOMI activities of interest to the hypoxia research community are highlighted.

  3. The influence of the Gulf Stream on wintertime European blocking

    Science.gov (United States)

    O'Reilly, Christopher H.; Minobe, Shoshiro; Kuwano-Yoshida, Akira

    2016-09-01

    Wintertime blocking is responsible for extended periods of anomalously cold and dry weather over Europe. In this study, the influence of the Gulf Stream sea surface temperature (SST) front on wintertime European blocking is investigated using a reanalysis dataset and a pair of atmospheric general circulation model (AGCM) simulations. The AGCM is forced with realistic and smoothed Gulf Stream SST, and blocking frequency over Europe is found to depend crucially on the Gulf Stream SST front. In the absence of the sharp SST gradient European blocking is significantly reduced and occurs further downstream. The Gulf Stream is found to significantly influence the surface temperature anomalies during blocking periods and the occurrence of associated cold spells. In particular the cold spell peak, located in central Europe, disappears in the absence of the Gulf Stream SST front. The nature of the Gulf Stream influence on European blocking development is then investigated using composite analysis. The presence of the Gulf Stream SST front is important in capturing the observed quasi-stationary development of European blocking. The development is characterised by increased lower-tropospheric meridional eddy heat transport in the Gulf Stream region and increased eddy kinetic energy at upper-levels, which acts to reinforce the quasi-stationary jet. When the Gulf Stream SST is smoothed the storm track activity is weaker, the development is less consistent and European blocking occurs less frequently.

  4. Evolution and hydrocarbon potential of offshore Pinar Del Rio area, Southern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tenreyro-Perez, R.; Lopez-Rivera, J.G.; Fernandez-Carmona, J.; Lopez-Quintero, J.O.

    1996-09-01

    The evolution of Southeast Gulf of Mexico comprises three main periods: pre-orogenic, syn-orogenic and post-orogenic. During pre-orogenic time, from Lower Jurassic to Campanian, the stages are the rift of Pangaea and the thermal subsidence (or drift). In drift stage two domains interacted in the space; the carbonate platforms (Bahamas, Yucatan, Organos and others), and the deepwater basins. These fluctuations were dictated by the differential subsidence and horizontal displacements of basement blocks as well as by the eustatic movements of the ocean. The Organos platform, for example, was entirely drowned since Upper Jurassic and the sedimentation continued in deepwater environment. The collision between Great Antilles Volcanic Arc and the continental margins since Upper Cretaceous modeled the Cuban orogen. Here, the southern facies thrusted over the northern section with simultaneous strike-slip movements. The interaction suddenly ceased in Eocene. The source rock levels are considerably more frequent in the deepwater domain than in the platforms. The Lower and Upper Jurassic as well as Lower and Middle Cretaceous horizons contain very high levels of organic matter. The offshore seismic shows the transition from the thrusted belt to the foreland basin with a typical triangle zone configuration. Reservoirs are expected in the Cretaceous section covered by seals conformed by early foreland basin sediments of Upper Cretaceous-Paleocene age. Foothill structures has a great potential for hydrocarbon exploration.

  5. Prey consumption and energy transfer by marine birds in the Gulf of Alaska

    Science.gov (United States)

    Hunt, G.L., Jr.; Drew, G.S.; Jahncke, J.; Piatt, J.F.

    2005-01-01

    We investigated prey consumption by marine birds and their contribution to cross-shelf fluxes in the northern Gulf of Alaska. We utilized data from the North Pacific Pelagic Seabird Database for modeling energy demand and prey consumption. We found that prey consumption by marine birds was much greater over the continental shelf than it was over the basin. Over the shelf, subsurface-foraging marine birds dominated food consumption, whereas over the basin, surface-foraging birds took the most prey biomass. Daily consumption by marine birds during the non-breeding season ("winter") from September through April was greater than daily consumption during the breeding season, between May and August. Over the shelf, shearwaters, murres and, in winter, sea ducks, were the most important consumers. Over the basin, northern fulmars, gulls and kittiwakes predominated in winter and storm-petrels dominated in May to August. Our results suggest that marine birds contribute little to cross-shelf fluxes of energy or matter, but they do remove energy from the marine system through consumption, respiration and migration. ?? 2005 Elsevier Ltd. All rights reserved.

  6. Environmental Assessment: Geothermal Energy Geopressure Subprogram. Gulf Coast Well Testing Activity, Frio Formation, Texas and Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-02-01

    This Environmental Assessment (EA) has been prepared to provide the environmental input into the Division of Geothermal Energy's decisions to expand the geothermal well testing activities to include sites in the Frio Formation of Texas and Louisiana. It is proposed that drilling rigs be leased before they are removed from sites in the formation where drilling for gas or oil exploration has been unsuccessful and that the rigs be used to complete the drilling into the geopressured zone for resource exploration. This EA addresses, on a regional basis, the expected activities, affected environment, and the possible impacts in a broad sense as they apply to the Gulf Coast well testing activity of the Geothermal Energy Geopressure Subprogram of the Department of Energy. Along the Texas and Louisiana Gulf Coast (Plate 1 and Overlay, Atlas) water at high temperatures and high pressures is trapped within Gulf basin sediments. The water is confined within or below essentially impermeable shale sequences and carries most or all of the overburden pressure. Such zones are referred to as geopressured strata. These fluids and sediments are heated to abnormally high temperatures (up to 260 C) and may provide potential reservoirs for economical production of geothermal energy. The obvious need in resource development is to assess the resource. Ongoing studies to define large-sand-volume reservoirs will ultimately define optimum sites for drilling special large diameter wells to perform large volume flow production tests. in the interim, existing well tests need to be made to help define and assess the resource.

  7. Estimating tsunami inundation from hurricane storm surge predictions along the U.S. gulf coast

    Science.gov (United States)

    Pampell-Manis, Alyssa; Horrillo, Juan; Figlus, Jens

    2016-06-01

    Gulf of Mexico (GOM) coasts have been included in the U.S. Tsunami Warning System since 2005. While the tsunami risk for the GOM is low, tsunamis generated by local submarine landslides pose the greatest potential threat, as evidenced by several large ancient submarine mass failures identified in the northern GOM basin. Given the lack of significant historical tsunami evidence in the GOM, the potential threat of landslide tsunamis in this region is assessed from a worst-case scenario perspective based on a set of events including the large ancient failures and most likely extreme events determined by a probabilistic approach. Since tsunamis are not well-understood along the Gulf Coast, we investigate tsunami inundation referenced to category-specific hurricane storm surge levels, which are relatively well established along the Gulf Coast, in order to provide information for assessing the potential threat of tsunamis which is more understandable and accessible to emergency managers. Based on tsunami inundation studies prepared for the communities of South Padre Island, TX, Galveston, TX, Mobile, AL, Panama City, FL, and Tampa, FL, we identify regional trends of tsunami inundation in terms of modeled storm surge inundation. The general trends indicate that tsunami inundation can well exceed the level of storm surge from major hurricanes in open beachfront and barrier island regions, while more interior areas are less threatened. Such information can be used to better prepare for tsunami events as well as provide a preliminary estimate of tsunami hazard in locations where detailed tsunami inundation studies have not been completed.

  8. Estimating tsunami inundation from hurricane storm surge predictions along the U.S. gulf coast

    Science.gov (United States)

    Pampell-Manis, Alyssa; Horrillo, Juan; Figlus, Jens

    2016-08-01

    Gulf of Mexico (GOM) coasts have been included in the U.S. Tsunami Warning System since 2005. While the tsunami risk for the GOM is low, tsunamis generated by local submarine landslides pose the greatest potential threat, as evidenced by several large ancient submarine mass failures identified in the northern GOM basin. Given the lack of significant historical tsunami evidence in the GOM, the potential threat of landslide tsunamis in this region is assessed from a worst-case scenario perspective based on a set of events including the large ancient failures and most likely extreme events determined by a probabilistic approach. Since tsunamis are not well-understood along the Gulf Coast, we investigate tsunami inundation referenced to category-specific hurricane storm surge levels, which are relatively well established along the Gulf Coast, in order to provide information for assessing the potential threat of tsunamis which is more understandable and accessible to emergency managers. Based on tsunami inundation studies prepared for the communities of South Padre Island, TX, Galveston, TX, Mobile, AL, Panama City, FL, and Tampa, FL, we identify regional trends of tsunami inundation in terms of modeled storm surge inundation. The general trends indicate that tsunami inundation can well exceed the level of storm surge from major hurricanes in open beachfront and barrier island regions, while more interior areas are less threatened. Such information can be used to better prepare for tsunami events as well as provide a preliminary estimate of tsunami hazard in locations where detailed tsunami inundation studies have not been completed.

  9. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter;

    2014-01-01

    of the folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...

  10. Transtensional Rifting in the Late Proto-Gulf of California Near Bahía Kino, Sonora, México

    Science.gov (United States)

    Bennett, S. E.; Oskin, M. E.; Dorsey, R. J.

    2009-12-01

    We investigate the role of obliquity in continental rupture from the example of the Gulf of California rift. Focused transtensional strain adjacent to strike-slip faults, ubiquitous in oblique rifts, may act as a catalyst for lithospheric rupture. To test this hypothesis we completed detailed structural mapping, fault kinematic analysis, basin analysis, and paleomagnetism of pre- and syn-rift volcanic and sedimentary rocks exposed in coastal Sonora, near Bahía Kino, México. This area is host to the NW-striking, dextral Sacrificio and Bahía Kino faults onshore that are likely linked to the offshore De Mar transform fault that accommodated Gulf opening. Three fault-bounded sedimentary basins formed unconformably above the 12.50 ± 0.08 Ma Tuff of San Felipe. The 6.53 ± 0.18 Ma Tuff of Cerro Tordillo and the 6.39 ± 0.02 Ma Tuffs of Mesa Cuadrada are interbedded in the lower part of the non-marine basin fill. In one of these basins, we used these tuff markers to calibrate a sedimentation rate of 1.2 ± 0.2 mm/yr and a tilting rate of 0.12 ± 0.02 °/kyr. These rapid rates suggest transtensional strain and related basin subsidence initiated ca. 6.6 Ma, near the end of proto-Gulf time. Paleomagnetism of the Tuff of San Felipe and Tuffs of Mesa Cuadrada in coastal Sonora show variable amounts of clockwise vertical-axis rotation when compared to paleomagnetic reference sites in Baja California. Fault blocks in the central and southern parts of the study area are rotated counter-clockwise 15° to clockwise 35°. Strike-slip faults in this area accommodate up to 10 km of slip. In contrast, ~53° of clockwise rotation occurred in the northern part of the study area, where strike-slip faults are absent. In this northern area, transtensional deformation occurred primarily by block rotation and ~6 km of normal slip on the low-angle (5-15°) Punta Chueca fault. After correcting for variable amounts of rotation, fault blocks display a consistent tilt down to the ENE. Pre

  11. K Basin safety analysis

    International Nuclear Information System (INIS)

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall

  12. K Basin safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Porten, D.R.; Crowe, R.D.

    1994-12-16

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall.

  13. A Geographic Information System (GIS) analysis for trace metal assessment of sediments in the Gulf of Paria, Trinidad

    International Nuclear Information System (INIS)

    The Gulf of Paria is a semi-enclosed shallow basin with increasing coastal development activities along Trinidad's west coast. Sediments present a host for trace metal pollutants from overlying waters, therefore determination of their content is critical in evaluating and detecting sources of marine pollution. This paper presents a Geographic Information System (GIS) analysis of geochemical assessment for trace metals in coastal sediments of the Gulf of Paria. This GIS approach facilitates interpretation of the spatial relationships among key environmental processes. The GIS development involves the integration of spatial and attribute data pertaining to bathymetry, current systems, topography, rivers, land use/land cover and coastal sediments. It employs spatial interpolation and retrieval operations to analyze the total trace metal concentrations of aluminum, copper and lead in the sediments and the clay-enriched sediments, to determine whether they are related to sediment type or are affected by the discharge from anthropogenic sources. Spatial distribution modeling of element concentrations are produced to indicate contamination plumes from possible anthropogenic sources such as rivers entering the Gulf of Paria, and to reveal potential hot spots and dispersion patterns. A direct spatial correlation between clay-enriched sediments and high concentrations of aluminum and lead is detected, however regions of high concentrations of copper and lead indicate a relationship to anthropogenic sources. The effectiveness of GIS for visualization, spatial query and overlay of geochemical analysis is demonstrated

  14. The Gulf of Cádiz pelagic ecosystem: A review

    Science.gov (United States)

    García Lafuente, Jesús; Ruiz, Javier

    2007-08-01

    The Gulf of Cádiz, strategically situated between the North Atlantic Ocean and the Mediterranean Sea, has been the focus of attention of a few oceanographic studies dealing with the deep circulation in order to understand the dynamics of the dense plume of Mediterranean water. Much less attention has been paid to the surface pelagic layer which holds important living resources of commercial and ecological interest. This overview summarizes the recent advances that have been made concerning the regional oceanography of the northern half of this important basin from an interdisciplinary point of view. Probably the most relevant oceanographic feature of the basin is its strong seasonality, which is linked to the meteorologically-induced seasonality of the eastern boundary current system of the North Atlantic. The prominent cape Santa Maria divides the continental shelf off the southern Iberian Peninsula in two shelves of different shape that hold different oceanographic processes, which in turn determine the characteristics of the pelagic ecosystem. Mass and energy inputs from land as well as tidally-driven processes makes the wider eastern shelf be more productive while the narrower western shelf, cut by a sharp submarine canyon, is under the influence of the almost-permanent upwelling spot off cape San Vicente. Under easterlies, the west-going, warm coastal countercurrent that is observed in the eastern shelf may invade the western shelf thus connecting biologically both shelves in an east-to-west direction. Westerlies induce generalised upwelling off the southern Iberia Peninsula, which adds to the almost-permanent one off cape San Vicente and generates an upwelling jet that moves eastwards. Cape Santa Maria may deflect this flow by generating a cold filament that extends southward and diverts water from the western shelf to the open ocean. This pattern of circulation hampers the biological connection between shelves in the west-to-east direction, which is

  15. Structural evolution of the southern transfer zone of the Gulf of Suez rift, Egypt

    Science.gov (United States)

    Abd-Allah, Ali M. A.; Abdel Aal, Mohamed H.; El-Said, Mohamed M.; Abd El-Naby, Ahmed

    2014-08-01

    We present a detailed study about the initiation and reactivations of Zeit-El Tor transfer zone, south Gulf of Suez rift, and its structural setting and tectonic evolution with respect to the Cretaceous-Cenozoic tectonic movements in North Egyptian margin. NE trending zone of opposed-dipping faults (22 km wide) has transferred the NE and SW rotations of the sub-basins in central and south Gulf of Suez rift, respectively. The evolution of this zone started by reactivation of the NE oriented late Neoproterozoic fractures that controlled the occurrence of Dokhan Volcanics in the rift shoulders. Later, the Syrian Arc contraction reactivated these fractures by a sinistral transpression during the Late Cretaceous-Eocene time. N64°E extension of the Oligo-Miocene rift reactivated the NE fractures by a sinistral transtension. During this rifting, the NE trending faults forming the transfer zone were more active than the rift-bounding faults; the Upper Cretaceous reverse faults in the blocks lying between these NE trending faults were rotated; and drape-related reverse faults and the positive flower structures were formed. Tectonic inversion from contraction to extension controlled the distribution and thickness of the Upper Cretaceous-Miocene rocks.

  16. Application of Thermal Modelling for Geochemical Characterization of Gadvan Formation, Persian Gulf, Iran

    Directory of Open Access Journals (Sweden)

    Ahmad Vaezian

    2014-12-01

    Full Text Available In the this research, the hydrocarbon generation potential of the Gadvan Formation as a probable source rock was investigated in the central part of the Persian Gulf at the borders of Iran. Type and maturity level of kerogen were investigated in six wells using the results of Rock-Eval pyrolysis and compared with results yielded by the modelling software program known as Pars Basin Modeler (PBM. The cross-plot of hydrogen index (HI versus maximum temperature suggests that the Gadvan Formation reached early to mid-maturity stages in the studied area, which means that it could act as a gas prone source rock. Furthermore, the burial and thermal history of the Gadvan Formation was determined in one well. Two methods, Easy %Ro and time-temperature index (TTI were used for the reconstruction of thermal modelling and studying the thermal maturity level in all of the drilled wells reaching the Gadvan Formation. The results of the TTI and Easy %Ro methods were in good agreement and both of confirmed the results of Rock Eval analysis. An integrated approach using different techniques showed that the Gadvan Formation can be classified as a poor gas bearing source rock in the studied area, while its maturity increases towards the southern parts of the Persian Gulf.

  17. Seismic-stratigraphic geochemical model of occurrence of oils in Gulf of Mexico flexure trend

    Energy Technology Data Exchange (ETDEWEB)

    Dinkelman, M.; Curry, D.J.

    1988-01-01

    Several models have recently been proposed for the generation and migration of the oil and gas in the Gulf of Mexico flexure trend. However, geologic and geochemical data suggest that much of the flexure trend oil was generated in Cretaceous-upper Tertiary sediments and migrated vertically through the faulting associated with continued salt tectonism. Generalized cross sections along the continental margin commonly show a thick, continuous salt layer. Regional seismic stratigraphic analysis shows that the salt is discontinuous in many places along the middle and lower slope owing to thinning and perforation caused by basinward creep, withdrawal, diapirism, and tonguing. The discontinuous salt distribution allows direct stratigraphic contact in places between the late Tertiary sediments and the underlying Paleogene and Cretaceous intervals. Seismic data indicate the salt movement has captured large volumes of slope and basinal sediments through ridging and tonguing. The onset of significant sediment loading on the shelf during the mid-Miocene to Pleistocene implies that shelf instability and sediment capture did not commence until the late Miocene. This scenario is consistent with geochemical data indicating that flexure trend oils are probably from carbonate-rich sources deposited in relatively shallow water. In contrast, Neogene sediments in the Gulf are clastic in nature, and were deposited in environments unfavorable for the accumulation of oil-prone organic matter. Mature migrated bitumens from carbonate sections recovered at DSDP Sites 535 and 540 are very similar geochemically to flexure trend oils.

  18. New Constraints on the Timing, Magnitude and Style of Deformation in the Southern Gulf of California: Oblique Rifting Since ~14-12 Ma

    Science.gov (United States)

    Kent, G. M.; Harding, A. J.; Sutherland, F. H.; Umhoefer, P. J.; Lizarralde, D.; Driscoll, N. W.

    2008-12-01

    A multichannel seismic (MCS) profile spanning 600 km across conjugate rifted margins in the southern Gulf of California provides insight into the spatial and temporal evolution of extension of the Baja peninsula away from mainland Mexico. Stratigraphic analysis of multiple rifted basins within the Alarcon spreading corridor indicates an initial stage of extension starting near or shortly after 14-12 Ma. This initial phase of extension was characterized by the formation of several large, widely distributed basins, that show little to no syn-rift sedimentation. A second phase of extension, likely synchronous with large-scale basin opening in the central and northern Gulf of California, began at or near 6 Ma, and was characterized by the formation of smaller half-grabens along both conjugate margins, with syn- and post-rift sedimentary sequences. A key feature imaged in the MCS data is a highly reflective, ropey layer at the top of basement with a maximum thickness variation ranging between 250-500 m. Travel-time modeling of common mid-point (CMP) supergathers shows that this layer has a P-wave velocity of around 2.5 km/s, overlying a basement velocity of 4 km/s. The ropey reflectivity patterns along with its low P-wave velocity suggests a volcanic origin, which is interpreted to be either late-stage Comondu volcano-clastics ending near 11 Ma, and/or early rifting volcanics that range in age between 10-9 Ma. This layer is imaged continuously over the Tamayo bank and appears to be mantling the Tamayo trough, partially concealing the largest episode of rift-induced subsidence. Basic extrapolation of sediment thickness to time of deposition within the largest basins in this corridor (i.e., Tamayo trough) suggests that the onset of rifting began at ~14-11 Ma. These new spatial and temporal constraints, when combined with a crustal thickness tomographic profile obtained across the entire Alarcon corridor, support a model of NW-SE oblique extension within the Gulf of

  19. Time series current meter data from buoys in the North Atlantic as part of the Deep Circulation in the Gulf of Maine Field Program from platforms GYRE and MARY LOUISE between July 25th, 1985 and August 2nd, 1987 (NODC Accession 0053940)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A two-year field study to investigate the deep flow between the major basins in the Gulf of Maine. This deep flow of warm-salty Slope water is an important driving...

  20. Geodynamics of the Gulf of California from surface wave tomography

    NARCIS (Netherlands)

    Zhang, X.; Paulssen, H.

    2012-01-01

    The Gulf of California, which forms part of the Pacific-North American plate boundary, is an ideal place to investigate upper mantle dynamics in a continental rifting area. With 19 seismic stations located around the gulf, the NARS-Baja experiment (2002-2008) was designed to image its crustal and ma

  1. Regional Industry Workforce Development: The Gulf Coast Petrochemical Information Network

    Science.gov (United States)

    Hodgin, Johnette; Muha, Susan

    2008-01-01

    The Gulf Coast Petrochemical Information Network (GC-PIN) is a workforce development partnership among industry businesses and area institutions of higher education in the four-county Gulf Coast region. GC-PIN partners develop new industry-specific curricula, foster industry career awareness, and retrain existing employees in new technologies.

  2. 78 FR 28292 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2013-05-14

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... War Veterans' Illnesses Task Force Draft Written Report is now complete. VA is inviting...

  3. 76 FR 65321 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2011-10-20

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... War Veterans' Illnesses Task Force Draft Written Report is now complete. VA is inviting...

  4. 75 FR 16577 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2010-04-01

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... Veterans' Illnesses Task Force Draft Written Report is now complete. The VA is inviting public comments...

  5. Seasonal surface connectivity in the Gulf of California

    Science.gov (United States)

    Marinone, S. G.

    2012-03-01

    A three-dimensional numerical model is used to study seasonal connectivity in the Gulf of California. From the Eulerian velocity fields of the model, particle trajectories were calculated for the 12 months of the year using an advection/diffusion scheme. Connectivity was quantified for twelve Gulf provinces with different dynamic/circulation characteristics being defined by the Eulerian velocity field: strong or weak coastal currents, eddies, and areas of mixing and exchange. Retention occurred for 9-12 months of the year in the Upper Gulf, Eddy and Sonora regions of the northern Gulf because of the Gulf-wide eddy circulation, which implies high potential for the auto-recruitment of larvae in this province. High retention was also found on the peninsula side of the southern Gulf in association with weaker residual currents, again implying potential for self-recruitment. In contrast, low retention was observed on the mainland side of the central and southern Gulf, from which particles are exported to many areas by the faster residual currents enhancing the potential for recruitment of distant coastal species. Empirical Orthogonal Function analyses revealed a strong annual and semiannual evolution in accordance with the strong seasonality of the Gulf dynamics.

  6. Sediment dispersal in the macro tidal Gulf of Kachchh, India

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S

    of the inner gulf is marked with U and V shaped cuttings extending in the parallel clays, deposited in an earlier phase of deposition. In the outer gulf, there exists a palaeo-channel, buried under 18 m thick sediments (in the central region). Existence...

  7. Good Order at Sea in the Gulf of Guinea

    DEFF Research Database (Denmark)

    Jacobsen, Katja Lindskov; Nordby, Johannes

    2015-01-01

    and Central African states decided to establish six maritime zones along their coastline in order to improve the maritime security in the Gulf of Guinea. A process heavily supported by UN’s International Maritime Organisation (IMO). Finally, the chapter suggests that maritime security issues in the Gulf...

  8. Rapid evolution of a Gulf Stream warm-core ring

    Science.gov (United States)

    Joyce, T.; Backus, R.; Cowles, T.; Baker, K.; Blackwelder, P.; Brown, O.; Evans, R.; Olson, D.; Fryxell, G.; Mountain, D.

    1984-01-01

    Satellite images are used to show that major alterations in the structure of Gulf Stream warm-core rings can occur during very short periods of two to five days when an interaction with the Gulf Stream is particularly intense. The role of these interactions in the evolution of a ring are discussed.

  9. Behavior and trends for Zn in Saronikos Gulf

    Directory of Open Access Journals (Sweden)

    Chalkiadakis O.

    2013-04-01

    Full Text Available The study of Zn in the water column of Saronikos Gulf in Greece during a two year period between 2008 and 2010 added data to the available time series of metal data for this marine area since 1985. The Saronikos Gulf, is directly influenced by the Athens metropolitan area. The operation of the Wastewater Treatment Plant of Athens situated on the small island of Psitalia, in 1995, was considered to be the turning point in the efforts of de-pollution of the gulf. Major sources of pollution for the gulf include also the port of Piraeus, with intensive navigation and shipping activities and the significant industrial activity occurring along the coast of Attica. This study of dissolved and particulate Zn gave results consistent with previous studies of the area such as the prevalence of the dissolved form of Zn and the most affected areas being the smaller most enclosed Gulf of Elefsina and Psitalia Island near the wastewater outfall. However, the concentrations of Zn were below toxic levels for marine aquatic organisms. Furthermore, a clear decrease in the Eastern part of the gulf was exhibited as well as a more subtle decrease in the gulf of Elefsina. The levels of Zn in Saronikos Gulf were found comparable to those of other Greek coastal areas.

  10. Cost of areal reduction of gulf hypoxia through agricultural practice

    Science.gov (United States)

    A major share of the area of hypoxic growth in the Northern Gulf of Mexico has been attributed to nutrient run-off from agricultural fields, but no estimate is available for the cost of reducing Gulf hypoxic area using agricultural conservation practices. We apply the Soil and Water Assessment Tool ...

  11. Coastal sensitivity mapping of Gulf of Kachchh and Gulf of Cambay, India

    Digital Repository Service at National Institute of Oceanography (India)

    ManiMurali, R.; Boora, P.; Vethamony, P.

    sq km. The intertidal biomass is very high at Vadinar and Sikka compared to Bedi and Okha. According to satellite data, the total reef area in the Gulf is 139.72 sq km. It has decreased from 217 sq km in 1975 to 139.7 sq km in 2011 which amounts to a...

  12. Gulf Stream Ring Coalescence with the Gulf Stream off Cape Hatteras.

    Science.gov (United States)

    Watts, D R; Olson, D B

    1978-12-01

    A cyclonic ring, which had separated from the Gulf Stream 7 months earlier and traveled 500 kilometers westward, collided with the stream in September 1977. Within 3 days the ring and stream joined to form a sharp S-shaped meander. Shipboard expendable temperature probes and four bottom-moored inverted echo sounders were used to obtain synoptic descriptions of the rejoining process.

  13. Wada basin boundaries and basin cells

    NARCIS (Netherlands)

    Nusse, H.E.; Yorke, J.A.

    1996-01-01

    In dynamical systems examples are common in which two or more attractors coexist, and in such cases the basin boundary is nonempty. We consider a two-dimensional diffeomorphism F (that is, F is an invertible map and both F and its inverse are differentiable with continuous derivatives), which has at

  14. Controls, budgets and variability of riverine sediment fluxes to the Gulf of Lions (NW Mediterranean Sea)

    Science.gov (United States)

    Sadaoui, Mahrez; Ludwig, Wolfgang; Bourrin, François; Raimbault, Patrick

    2016-09-01

    The present study investigates the spatio-temporal variability of riverine sediment fluxes to the Gulf of Lions, one of the most extensive shelf regions in the Mediterranean Sea. Small coastal rivers compete here with the Rhone River, nowadays the largest Mediterranean river in terms of water discharge. Our scientific objectives were to investigate the major controls of riverine sediment yields (SY) in this area and to quantify the role of the small coastal rivers, largely ignored in previous studies, in the total sediment budgets. Another objective concerned the source identification of the Rhone sediments with regard to the major tributary contributions, and to test whether the sediment fluxes are in equilibrium in the basin. For the calculation of representative long-term fluxes, we used a Simplified Rating Curve Approach (SiRCA) which could be validated by high resolution monitoring and existing literature data. An overall of 13 drainage basins could be distinguished, covering about 86% of the study area (6 coastal rivers, the Rhone River, and 6 of its tributaries). Representative SY range from 19 to 151 t km-2 yr-1 in the investigated drainage basins. Despite their smaller basin areas and more torrential discharge regimes, SY of the coastal rivers were generally lower compared to SY of the Rhone River and its tributaries. Confrontation with the lithological, morphological and hydroclimatic basin characteristics indicate that lithology exerts the dominant control on SY in the study region. In particular, the existence of erodible sedimentary rocks in the headwater regions yields high SY. Peak values of 135 and 151 t km-2 yr-1 were observed for the Isere and Durance tributaries of the Rhone River, where badlands exist. The coastal rivers contribute on average only to slightly more than 5% of the long-term sediment inputs to the Gulf of Lions. During individual years however, their contribution can strongly increase (up to 27% in 2011). Their contribution is

  15. Shallow seismic study of the geothermal areas in the Gülbahçe Bay and İzmir Gulf (Aegean Sea, Western Turkey)

    Science.gov (United States)

    Altan, Zehra; Ocakoǧlu, Neslihan

    2016-09-01

    The two seismic units, i.e., the basement and the basin sediments are interpreted as Miocene and Plio-Quaternary deposits, respectively. The basin sediments of approximately 255 m thickness are risen and compressed through the active strike-slip faults, GF1-GF3 extending in N-S direction towards the outer Gülbahçe Bay. These compressed sediments are interpreted as upwelling zones with weak reflection character and internal frequency attenuation. The most significant one is marked as a possible mud diaper zone with a ~320 m width and the approximately 500 m. A synthetic model of the field data gathered from the diaper indicates that the top of the diapir is characterised by a strong positive reflection character while the internal diaper is represented by polarity reversals and weak reflections due to a velocity decrease with depth. Moreover, phase changes are observed at the border of the diapiric structure. A relatively thicker basin sediment unit of approximately 700 m was observed on the pro-delta sediments of the Gediz River and the sediments below in the İzmir Gulf. The active strike-slip faults, İF1-İF5 deform the basement and basin deposits. Moreover, two active normal faults, İF6 and İF7 are marked from inner to outer part of the gulf. The seismic attribute sections indicate weak reflection zones and frequency attenuation particularly both inside the pro-delta sediments and the sediments below. Observations suggest to us the existence of possible fluid and/or gas discharges and saturations in the Gülbahçe Bay and İzmir Gulf.

  16. Distribution, diet, and energetic condition of age-0 walleye pollock (Gadus chalcogrammus) and pacific cod (Gadus macrocephalus) inhabiting the Gulf of Alaska

    Science.gov (United States)

    Moss, Jamal H.; Zaleski, Marilyn F.; Heintz, Ron A.

    2016-10-01

    Walleye pollock (Gadus chalcogrammus) and Pacific cod (Gadus macrocephalus) are commercially and ecologically important species in Alaska waters. Little is known about their ecology after transitioning from larvae to free swimming fish until settlement to nursery habitats in the eastern Gulf of Alaska. Differences in the distribution, diet, body size, and energetic status between the eastern and central Gulf of Alaska were investigated during summer months to better understand regional and interspecific differences in life history and ecology. The composition of zooplankton prey in the diets of walleye pollock and Pacific cod inhabiting shelf waters was more varied relative to those inhabiting the slope and basin. Body condition and total energy content of Pacific cod was greater than walleye pollock, however total energy content increased with length at a similar rate for both species. Walleye pollock inhabiting continental slope waters had higher energy stores relative to those inhabiting the continental shelf and basin, indicating an energetic advantage for individuals remaining off the shelf during summer months or potentially the advection of fish with higher energy reserves off of the shelf. Previous studies have documented the importance of energy stores for surviving winter and future studies should focus on understanding the mechanisms influencing lipid storage and somatic growth for walleye pollock and Pacific cod inhabiting the eastern and central Gulf of Alaska.

  17. Reserves in western basins

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  18. Three-dimensional flushing times of the Persian Gulf

    Science.gov (United States)

    Sadrinasab, Masoud; Kämpf, Jochen

    2004-12-01

    A three-dimensional hydrodynamic model is employed in a fully prognostic mode to derive flushing times of the Persian Gulf-an evaporation-driven inverse estuary that is governed by import of surface water from the adjacent ocean and export of saline bottom gulf water through the Strait of Hormuz. During spring and summer, a cyclonic overturning circulation establishes along the full length of the Gulf. During autumn and winter, this circulation breaks up into mesoscale eddies, laterally stirring most of the Gulf's surface waters. As a result of this, 95% flushing times of surface waters are shortest (1-3 yr, increasing with distance from the Strait) along the Iranian coast, but are much longer (>5 yr) along the coasts of Kuwait and Saudi Arabia. Owing to density stratification introduced by the surface inflow of ocean water, flushing times of bottom waters are ~6 yr in most parts of the Gulf.

  19. NASA Earth Observations Track the Gulf Oil Spill

    Science.gov (United States)

    Jones, Jason B.; Childs, Lauren

    2010-01-01

    The NASA Applied Sciences Program created the Gulf of Mexico Initiative (GOMI) in 2007 "to enhance the region s ability to recover from the devastating hurricanes of 2005 and to address its coastal management issues going into the future." The GOMI utilizes NASA Earth science assets to address regional priorities defined by the Gulf of Mexico Alliance, a partnership formed by the states of Alabama, Florida, Louisiana, Mississippi, and Texas, along with 13 federal agencies and 4 regional organizations to promote regional collaboration and enhance the ecological and economic health of the Gulf of Mexico. NASA's GOMI is managed by the Applied Science and Technology Project Office at Stennis Space Center and has awarded over $18 million in Gulf of Mexico research since 2008. After the Deepwater Horizon oil spill, GOMI personnel assisted members of the Gulf of Mexico Alliance with obtaining NASA remote sensing data for use in their oil spill response efforts.

  20. Abundance and size of Gulf shrimp in Louisiana's coastal estuaries following the Deepwater Horizon oil spill.

    Directory of Open Access Journals (Sweden)

    Joris L van der Ham

    Full Text Available The Deepwater Horizon oil spill impacted Louisiana's coastal estuaries physically, chemically, and biologically. To better understand the ecological consequences of this oil spill on Louisiana estuaries, we compared the abundance and size of two Gulf shrimp species (Farfantepeneus aztecus and Litopeneus setiferus in heavily affected and relatively unaffected estuaries, before and after the oil spill. Two datasets were used to conduct this study: data on shrimp abundance and size before the spill were available from Louisiana Department of Wildlife and Fisheries (LDWF. Data on shrimp abundance and size from after the spill were independently collected by the authors and by LDWF. Using a Before-After-Control-Impact with Paired sampling (BACIP design with monthly samples of two selected basins, we found brown shrimp to become more abundant and the mean size of white shrimp to become smaller. Using a BACIP with data on successive shrimp year-classes of multiple basins, we found both species to become more abundant in basins that were affected by the spill, while mean shrimp size either not change after the spill, or increased in both affected and unaffected basins. We conclude that following the oil spill abundances of both species increased within affected estuaries, whereas mean size may have been unaffected. We propose two factors that may have caused these results: 1 exposure to polycyclic aromatic hydrocarbons (PAHs may have reduced the growth rate of shrimp, resulting in a delayed movement of shrimp to offshore habitats, and an increase of within-estuary shrimp abundance, and 2 fishing closures established immediately after the spill, may have resulted in decreased fishing effort and an increase in shrimp abundance. This study accentuates the complexities in determining ecological effects of oil spills, and the need of studies on the organismal level to reveal cause-and-effect relationships of such events.

  1. Abundance and size of Gulf shrimp in Louisiana's coastal estuaries following the Deepwater Horizon oil spill.

    Science.gov (United States)

    van der Ham, Joris L; de Mutsert, Kim

    2014-01-01

    The Deepwater Horizon oil spill impacted Louisiana's coastal estuaries physically, chemically, and biologically. To better understand the ecological consequences of this oil spill on Louisiana estuaries, we compared the abundance and size of two Gulf shrimp species (Farfantepeneus aztecus and Litopeneus setiferus) in heavily affected and relatively unaffected estuaries, before and after the oil spill. Two datasets were used to conduct this study: data on shrimp abundance and size before the spill were available from Louisiana Department of Wildlife and Fisheries (LDWF). Data on shrimp abundance and size from after the spill were independently collected by the authors and by LDWF. Using a Before-After-Control-Impact with Paired sampling (BACIP) design with monthly samples of two selected basins, we found brown shrimp to become more abundant and the mean size of white shrimp to become smaller. Using a BACIP with data on successive shrimp year-classes of multiple basins, we found both species to become more abundant in basins that were affected by the spill, while mean shrimp size either not change after the spill, or increased in both affected and unaffected basins. We conclude that following the oil spill abundances of both species increased within affected estuaries, whereas mean size may have been unaffected. We propose two factors that may have caused these results: 1) exposure to polycyclic aromatic hydrocarbons (PAHs) may have reduced the growth rate of shrimp, resulting in a delayed movement of shrimp to offshore habitats, and an increase of within-estuary shrimp abundance, and 2) fishing closures established immediately after the spill, may have resulted in decreased fishing effort and an increase in shrimp abundance. This study accentuates the complexities in determining ecological effects of oil spills, and the need of studies on the organismal level to reveal cause-and-effect relationships of such events.

  2. A Paleomagnetic Investigation of Large-Scale Vertical Axis Rotations in Coastal Sonora: Evidence for Transtensional Proto-Gulf Deformation

    Science.gov (United States)

    Herman, S. W.; Gans, P. B.

    2006-12-01

    A paleomagnetic investigation into possible vertical axis rotations has been conducted in the Sierra el Aguaje and Sierra Tinajas del Carmen, Sonora, Mexico, in order assess proposed styles for oblique continental rifting in the Gulf of California. Two styles of rifting have been proposed; (1) strain partitioning (Stock and Hodges, 89), and (2) transtension (Gans, 97), for the Proto-Gulf period of the Gulf of California. The presence of large- scale vertical axis rotations would lend weight to the argument for transtension. The Sierra el Aguaje and Sierra Tinajas del Carmen are located in southwestern coastal Sonora, Mexico. The ranges represent the eastern-rifted margin of the central Gulf of California. This is one of the few areas of that margin which is entirely above water, with new ocean crust of the Guaymas basin lying immediately offshore of the western edge of the ranges. The ranges are composed of volcanic units and their corresponding volcaniclastic units that are the result of persistent magmatic activity between 20 and 8.8 Ma, including three packages of basalt and andesite that make excellent paleomagnetic recorders. Based on cross cutting relations and geochronologic data for pre-, syn-, and post-tectonic volcanic units, most of the faulting and tilting in the Sierra El Aguaje and Sierra Tinajas del Carmen is bracketed between 11.9 and 9.0 Ma, thus falling entirely within Proto-Gulf time. Existing field relations suggest the presence of large (>45°) vertical axis rotations in this region. This evidence includes: a) abrupt changes in the strike of tilted strata in different parts of the range b) ubiquitous NE-SW striking faults with left lateral-normal oblique slip, that terminate against major NW-trending right lateral faults, and c) obliquity between the general strike of tilted strata and the strike of faults. The results of the paleomagnetic investigation are consistent with the field evidence and show large clockwise rotations between ~30° and

  3. Processes in Environmental Depositional Systems and Deformation in Sedimentary Basins: Goals for Exoloration in Mexico

    Science.gov (United States)

    Sandoval-Ochoa, J.

    2005-05-01

    Among the recent needs to establish new goals in the mexican energy industry to increase the petroleum reserves, has been necessary to recapitulate on some academic an operative concepts and definitions applied to the Petroliferous Basins Exploration; first of all, in order to understand the Petroleum System in given tectonophysical framework. The tectonophysical environment experienced by the petroliferous basin in the southwestern Gulf of Mexico, merely in the Campeche Sound and adjacent terrestrial regions (Figure 1); has been the result of interaction among the tectonic plates, the Coco's Plate with impingement and subduction beneath the Northamerican Plate and the Yucatán Microplate and even in very deep connection with the oceanic crust of southwesternmost portion of the Gulf of Mexico and the one of the Caribbean sea beneath the gulf of Belize-Honduras. The tectonosedimentary effects in the Campeche Bay starting with the skeleton formed for the Cenozoic Era, kept simultaneous conditions in depositions and deformations because of strain, stress and collapse fields, acted through this Era up to the present day, as observed in the surface Aguayo et al, 1999 and Sandoval, 2000. The involved portions of the crust and its boundaries have also been performing the relative sinking of the mere southwestern centre of the Gulf of Mexico, and the rising of the southeastern lands of Mexico. In the middle contiguity are found the productive Tertiary basins of: Comalcalco, Macuspana, Salina del Itsmo, Campeche-Champoton and other in deep waters; all of them, in an arrangement of basins among distensive faulted blocks in echelon, falling down to the deep centre of the Gulf Sandoval, op cit. With this scenario and that ones of other basins, a recapitulation on concepts and definitions, has been made on the regional natural processes of the environmental depositional systems and on the basins analysis in the tectonophysical framework, in order to reflect on the

  4. 75 FR 9116 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2010-03-01

    ... 29 (74 FR 44732). These measures allow for more efficient functioning of the grouper and tilefish IFQ... implementing Amendment 29 to the Fishery Management Plan for Reef Fish Resources of the Gulf of Mexico (FMP), as prepared and submitted by the Gulf of Mexico Fishery Management Council (Council). Amendment...

  5. 76 FR 9735 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2011-02-22

    ..., approximately one-third of the Gulf was closed to fishing for much of the summer. The direct loss of fishing... be expected to directly affect commercial and for-hire fishing vessels that harvest red snapper in... (Gulf) reef fish fishery for the 2011 fishing year, provided that NMFS determines the total...

  6. 75 FR 63786 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2010-10-18

    ... proposed temporary rule that would implement interim measures to reduce overfishing of gag in the Gulf of... this proposed rule is to reduce overfishing of the gag resource in the Gulf. DATES: Written comments... prevent overfishing and achieve, on a continuing basis, the optimum yield (OY) from Federally managed...

  7. 76 FR 78245 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery...

    Science.gov (United States)

    2011-12-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XA727 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery; South Atlantic Snapper-Grouper Fishery...

  8. 76 FR 64327 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery...

    Science.gov (United States)

    2011-10-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XA727 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery; South Atlantic Snapper-Grouper Fishery...

  9. 75 FR 74650 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2010-12-01

    ...-third of the Gulf EEZ, from western Louisiana east to the panhandle of Florida and south to Campeche Bay... 18, 2010, NMFS published the proposed temporary rule and requested public comment (75 FR 63786). This... Amendment 31 (75 FR 21512; April 26, 2010) have reduced the number of longline vessels in the Gulf reef...

  10. Citizenship and migration in Arab Gulf monarchies

    DEFF Research Database (Denmark)

    Sater, J.

    2014-01-01

    , whereas fear and security concerns are often embedded in more populist debates. In the Arab Gulf region, as in many other regions, such as East Asia, this debate has taken distinctively different shapes, partially because the concept of citizenship remains a contested notion not just with regard to...... migrants, but also with regard to local populations. In addition to the contested nature of citizenship, migrants' lack of citizenship rights fulfils distinctive functions in what Saskia Sassen calls 'global cities'. This concept links the Arab world with a new phenomenon of globalized migration in which...

  11. The July 1990 Gulf Stream Experiment

    Science.gov (United States)

    Valenzuela, G. R.; Mied, R. P.; Ochadlick, A. R.; Kobrick, M.; Smith, P. M.; Askari, F.; Lai, R. J.; Sheres, D.; Morrison, J. M.; Beal, R. C.

    1991-01-01

    The specific scientific tasks addressed in the July 1990 Gulf Stream (GS) experiment were the following: (1) Kelvin wake behavior across fronts at various ship speeds, (2) the physics of temperature front/radar cross section (RCS) mismatch, (3) wave-current interactions in curvature fronts, and (4) the hydrodynamic structure and origin of synthetic-aperture-radar (SAR) slick-like features. Overall, the GS Experiment was most successful, and about 60 percent of the planned data was collected. On-going efforts concentrate on the analysis and interpretation of the data. An overview of the experiment and preliminary results of the data analysis are given.

  12. Physical Oceanography of the Gulf of Aden

    Digital Repository Service at National Institute of Oceanography (India)

    Al Saafani, M.A.

    gradient force andtheCoriolisforce. Thisiscalled”geostrophicbalance”orgeostrophy. Whenthe flow is geostrophic, forces and accelerations other than the pressure gradient and Coriolis force become negligible . Under geostrophic balance, the pressure gradient...) in the west of A1 in both data sets; but the drop in sea level has not manifested as a cyclonic eddy. The existence of low sea level interspaced with high sea level (A1) manifests as a meandering eastward flow in Circulation in the Gulf ofAden 100 Figure 4...

  13. 78 FR 50030 - Implementation of New Gulf Coast Ecosystem Restoration Science, Observation, Monitoring, and...

    Science.gov (United States)

    2013-08-16

    ... modeling efforts and plans (e.g., NRDA science, Gulf of Mexico States' Centers of Excellence, Gulf of Mexico Research Initiative, Gulf Coast Ecosystem Restoration Strategy and associated Science Needs.... Numerous documents have been developed in recent years that identify science needs in the Gulf of...

  14. Marine Magnetic Anomalies of the Northern Part of the Gulf of Aqaba, Dead Sea Rift

    Science.gov (United States)

    Al-Zoubi, A.

    2009-04-01

    MARINE MAGNETIC ANOMALIES OF THE NORTHERN PART OF THE GULF OF AQABA, DEAD SEA RIFT Al-Zoubi (1), Z. Ben-Avraham (2), T. M. Niemi (3), E. Akawi (1), G. Tibor (4), R. Al-Rzouq (1), J.K. Hall (5), A. Abueladas (1), G. Hartman (2) (1) Surveying & Geomatics Department, Al-Balqa' Applied University, Salt, Jordan (2) Department of Geophysics & Planetary Sciences, Tel-Aviv University, Tel-Aviv, Israel (3) University of Missouri-Kansas City, USA. (4) Israel Oceanographic and Limnological Research, Haifa, Israel (5) Geological Survey of Israel, Jerusalem, Israel A high-resolution marine magnetic survey in the northern part of the Gulf of Aqaba, Dead Sea Rift was carried out during October and November 2006. The survey led by an international research group (Israel, Jordan, and USA) funded by MERC, USA and aims to provide the municipalities of Aqaba and Elat a base map of active faults for seismic hazard assessment. The total magnetic intensity at sea surface was measured by a proton precession magnetometer. Diurnal magnetic variation was corrected from the data by using the observation located in southern part of Israel during the survey period. The correction of the external field variation was carried out based on the continuous magnetic observations at a reference magnetic observatory close to the survey area. For calculations of the total intensity of magnetic anomaly, the IGRF model was used as the core field model in accordance with the recommendation of the IAGA. Geomagnetic total intensity anomaly map of the study area has been produced. The magnetic anomaly map shows that there are two major magnetic trends appear in the study area. These are the magnetic high across the northwest section of the Gulf and a magnetic low across the southeast section. These two general trends are divided by a northeast-trending boundary. The magnetic map reveals a complex faults system between the deep part of the Gulf as a pull-apart basin and the on land transform fault in the Araba

  15. Tulare Basin protection plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Tulare Basin Protection Plan has been initiated by The Nature Conservancy to elucidate the problems and opportunities of natural diversity protection....

  16. Mitigation : Closed Basin Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The upcoming meeting on waterfowl mitigation for the Closed Basin Project will have several people talk about possible changes to the waterfowl mitigation program....

  17. Early Mesozoic basin aquifers

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the extent of the Early Mesozoic basin aquifers in the states of Massachusettes, Connecticut, New York, New Jersey, Pennsylvania, Maryland,...

  18. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  19. K Basin Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    PECH, S.H.

    2000-08-23

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  20. Offshore and onshore stratigraphic constraints to rebuild the evolution of the two conjugate margins (Gulf of Lion and West Sardinia) over the last 30 Myr

    Science.gov (United States)

    Leroux, Estelle; Gorini, Christian; Rubino, Jean-Loup; Rabineau, Marina; Aslanian, Daniel; Blanpied, Christian; Taillepierre, Rachel; Haq, Bilal

    2016-04-01

    Principles of seismic and sequential stratigraphy [Vail et al., 1977] are applied onto an extensive set of seismic reflection and drilling data in the Provençal Basin to correlate post-rift Miocene and Plio-Quaternary chronostratigraphic markers at the basin-wide scale. Stratigraphic, sedimentological and micropaleontological studies [Cravatte et al., 1974] for some of the boreholes provide additional information on the depositional environments and the chronostratigraphy of the drilled series. Synthesis of previous onshore studies on the both conjugate margins (Gulf of Lion and West Sardinia), and new fieldwork [Rueda, 2014] enable us to establish the stratigraphical link between onshore and offshore syn-rift and post-rift sequences. Miocene peri-Alpine foreland basin is particularly connected toward the south with the Gulf of Lion passive margin and is predominantly filled by marine shallow water siliciclastic deposits ranging from lower Miocene to Pliocene in age. Nine to ten depositional onshore sequences are identified [Besson et al., 2005, Rubino et al., 2015] and can be traced into the post rift part of the Gulf of Lion. The recognition of these sequences on the distal part of the shelf from the Burdigalian to the Messinian with a good well calibration is fully consistent and integrated in a chronostratigraphic history of the Provençal Basin over the last 30 Myr. We quantify, model and discuss the evolution of vertical movements and sediment budgets since the rifting. This study also allows us to construct a complete sea-level change curve for the western Mediterranean Neogene. Besson, D. (2005). Architecture du bassin rhodano-provençal miocène (Alpes, SE France). Relations entre déformation, physiographie et sédimentation dans un bassin molassique d'avant-pays (Doctoral dissertation, Paris, ENMP). Rueda, T. (2014). Analyse sédimentologique et stratigraphique du remplissage Oligo-Aquitanien du fossé du Campidano - Comparaison avec le remplissage

  1. Phytoplankton and sediments in Gulf of Mexico

    Science.gov (United States)

    2002-01-01

    Affected both by terrestrial factors like agriculture, deforestation, and erosion, and by marine factors like salinity levels, ocean temperature and water pollution, coastal environments are the dynamic interface between land and sea. In this MODIS image from January 15, 2002, the Gulf of Mexico is awash in a mixture of phytoplankton and sediment. Tan-colored sediment is flowing out into the Gulf from the Mississippi River, whose floodplain cuts a pale, wide swath to the right of center in the image, and also from numerous smaller rivers along the Louisiana coast (center). Mixing with the sediment are the multi-colored blue and green swirls that reveal the presence of large populations of marine plants called phytoplankton. Phytoplankton populations bloom and then fade, and these cycles affect fish and mammals-including humans-higher up the food chain. Certain phytoplankton are toxic to both fish and humans, and coastal health departments must monitor ecosystems carefully, often restricting fishing or harvesting of shellfish until the blooms have subsided.

  2. Plate boundary deformation at the latitude of the Salton Trough - northern Gulf of California (Invited)

    Science.gov (United States)

    Stock, J. M.

    2013-12-01

    Along the Pacific-North America plate boundary zone, the segment including the southern San Andreas fault to Salton Trough and northern Gulf of California basins has been transtensional throughout its evolution, based on Pacific-North America displacement vectors calculated from the global plate circuit (900 × 20 km at N54°W since 20 Ma; 460 × 20 km at N48°W since 11 Ma). Nevertheless, active seismicity and focal mechanisms show a broad zone of plate boundary deformation within which the inferred stress regime varies locally (Yang & Hauksson 2013 GJI), and fault patterns in some regions suggest ongoing tectonic rotation. Similar behavior is inferred to have occurred in this zone over most of its history. Crustal structure in this region is constrained by surface geology, geophysical experiments (e.g., the 2011 Salton Seismic Imaging Project (SSIP), USGS Imperial Valley 1979, PACE), and interdisciplinary marine and onland studies in Mexico (e.g., NARS-Baja, Cortes, and surveys by PEMEX). Magnetic data (e.g., EMAG-2) aids in the recognition of large-scale crustal provinces and fault boundaries in regions lacking detailed geophysical surveys. Consideration of existing constraints on crustal thickness and architecture, and fault and basin evolution suggests that to reconcile geological deformation with plate motion history, the following additional factors need to be taken into account. 1) Plate boundary displacement via interacting systems of rotating blocks, coeval with slip on steep strike slip faults, and possibly related to slip on low angle extensional faults (e.g, Axen & Fletcher 1998 IGR) may be typical prior to the onset of seafloor spreading. This fault style may have accommodated up to 150 km of plate motion in the Mexican Continental Borderland and north of the Vizcaino Peninsula, likely between 12 and 15 Ma, as well as explaining younger rotations adjacent to the Gulf of California and current deformation southwest of the Salton Sea. 2) Geophysical

  3. The Aquitaine basin

    Energy Technology Data Exchange (ETDEWEB)

    Biteau, J.-J.; Le Marrec, A.; Le Vot, M.; Masset, J.-M.

    2006-07-01

    The Aquitaine Basin is located in the southwest of France, between the Gironde Arch in the north and the Pyrenean Mountain Chain in the south. It is a triangular-shaped domain, extending over 35000km{sup 2}. From north to south, six main geological provinces can be identified: (1) the Medoc Platform located south of the Gironde Arch; (2) the Parentis sub-basin; (3) the Landes Saddle; (4) the North Aquitaine Platform; (5) the foreland of the Pyrenees (also known as the Adour, Arzacq and Comminges sub-basins); and (6) the Pyrenean fold-and-thrust belt. Only the Parentis sub-basin, the foreland of the Pyrenean Chain and a minor part of the fold-and-thrust belt itself are proven hydrocarbon provinces. The Aquitaine Basin, in turn, is subdivided into four sub-basins - the Parentis, Adour-Arzacq, Tarbes and Comminges areas. The lozenge shape of these depocentres is related to the Hercynian tectonic framework of the Palaeozoic basement, reactivated during Early Cretaceous rifting. This rift phase aborted at the end of the Albian (prior to the development of an oceanic crust) in response to the beginning of the subduction of the Iberian plate under the European plate. During the Upper Cretaceous, continued subduction led to the creation of northwards-migrating flexural basins. In the Eocene, a paroxysmal phase of compression was responsible for the uplift of the Pyrenean Mountain Chain and for the thin-skinned deformation of the foreland basin. The resulting structuration is limited to the south by the internal core of the chain and to the north by the leading edge of the fold-and-thrust belt, where the Lacq and Meillon gas fields are located. Four main petroleum provinces have been exploited since the Second World War: (1) the oil-prone Parentis sub-basin and (2) salt ridges surrounding the Arzacq and Tarbes sub-basins; and (3) the gas-prone southern Arzacq sub-basin (including the external Pyrenean fold-and-thrust belt and the proximal foreland sub-basin) and (4

  4. Gulf States and the Conflict between India and Pakistan

    Directory of Open Access Journals (Sweden)

    Zahid Shahab Ahmed

    2010-05-01

    Full Text Available Traditional cultural and economic ties between the Indian subcontinent and the Gulf region have existed for several centuries now. Strengthened further, both India and Pakistan continue to have important economic and strategic ties with the countries of the Gulf. While the Gulf region offers substantial economic advantages to both, they also have the potential to make positive interventions in the bilateral conflict between India and Pakistan. The following chapter analyses the role and position of the Gulf Arab States - in particular the member states of the Gulf Cooperation Council (GCC, and their potential in acting as a buffer for the Indo-Pak conflict. It will evaluate the official positions of the Gulf region towards various aspects of the Indo-Pak conflict. The Gulfcountries have often voiced their positions at regional and internationalforums. An additional aspect of this relationship is that the Gulf States are also members of the Organization of Islamic Conference (OIC, a pan- Islamic body which has often addressed issues of contention between India and Pakistan, particularly with respect to Kashmir. Through an academic understanding of the issues and incorporating viewpoints of experts in the area, the chapter seeks to provide fresh insights into an aspect which has the possibility of becoming a crucial incentive for peace between India and Pakistan.

  5. Numerical model of circulation and residence times in the Persian Gulf

    Science.gov (United States)

    O'Donncha, Fearghal; Ragnoli, Emanuele

    2014-05-01

    The Persian Gulf is a semi-enclosed, marginal sea that is exposed to arid, subtropical climate. As a consequence of the extreme climate, evaporation is greater than freshwater inflow resulting in a net loss of water and associated, reverse flow, estuarine circulation as the highly saline waters exit the basin through the Straits of Hormuz, into the Gulf of Oman. Because of their consistent direction, these density currents are central in the distribution and removal of pollutants from the gulf. Tidal forcing impacts circulation in the region, particularly on smaller scales of length and time. Wind forcing can be significant, particularly the Shamal weather phenomenon; wind that sets in with great abruptness and force, and is related to synoptic weather systems to the Northwest. Output from high resolution (~1km) numerical simulations, using NEMO (Nucleus for European Modelling of the Ocean), provide insight into the physical oceanography of the region. The model was forced by 0.75° European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric data and tidal constituents extracted from the Oregon State University Tidal Prediction Software (OTPS/TPXO). Model results permit a detailed examination of the three primary forcing processes, namely: tidal forces, wind forces, and density differences. To assess fundamental model performance, results are compared with two historical observation datasets: (1) a comprehensive dataset of velocity and CTD measurements collected by Reynolds (1993) and (2) time series measurements recorded in the Strait of Hormuz from December 1996 to March 1998 by Johns et al. (2003). Model results exhibit close agreement to field values validating the model for a more detailed analysis of circulations patterns within the gulf. To better elucidate the dominant forcing processes, classical tidal analysis decomposed the flow currents by fitting the flow profile to a finite set of sinusoids at specific frequencies related to astronomical

  6. Evidence for atmospheric carbon dioxide variability over the Gulf Stream

    Science.gov (United States)

    Bufton, J. L.

    1984-01-01

    Two airborne surveys of atmospheric carbon dioxide concentration have been conducted over the Gulf Stream off the east coast of Virginia and North Carolina on September 7-8, 1983. In situ CO2 data were acquired at an aircraft altitude of 300 m on trajectories that transcected the Gulf Stream near 36 deg N 73 deg W. Data show evidence of a CO2 concentration increase by 4 ppm to 15 ppm above the nominal atmospheric background value of 345 ppm. These enhanced values were associated with the physical location of the Gulf Stream prior to the passage of a weak cold front.

  7. SAR observations of the Gulf Stream during SWADE

    Science.gov (United States)

    Vachon, Paris W.; Liu, Antony K.; Mollo-Christensen, Erik

    1992-01-01

    The Surface Wave Dynamics Experiment (SWADE) has gathered SAR observations of the Gulf Stream that show a change in ocean surface brightness; this may be due to the effects of a change in air-sea temperature difference across the observed edge, where the boundary is defined by warm, quickly flowing Gulf Stream water and cooler, relatively stationary shelf water. The two images discussed indicate the possibility of deepening understanding of Gulf Stream front dynamics by using the abundant spatial data of SAR imagery, in conjunction with more conventional (point-like) data on hydrography and currents.

  8. Gulf Stream density structure and transport during the past millennium

    OpenAIRE

    Lund, David C.; Lynch-Stieglitz, Jean; Curry, William B.

    2006-01-01

    The Gulf Stream transports approximately 31 Sv (1 Sv = 10^6 m^3 s^(-1)) of water and 1.3 10^(15) W of heat into the North Atlantic ocean. The possibility of abrupt changes in Gulf Stream heat transport is one of the key uncertainties in predictions of climate change for the coming centuries. Given the limited length of the instrumental record, our knowledge of Gulf Stream behaviour on long timescales must rely heavily on information from geologic archives. Here we use foraminifera from a su...

  9. Northern Gulf Littoral Initiative (NGLI), Geology and Physical Properties of Marine Sediments in the N.E. Gulf of Mexico: Data Report

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Northern Gulf Littoral Initiative (NGLI), Geology and Physical Properties of Marine Sediments in the N.E. gulf of Mexico: Data Report, was produced by the U.S....

  10. Population Structure, Abundance and Movement of Whale Sharks in the Arabian Gulf and the Gulf of Oman

    Science.gov (United States)

    Robinson, David P.; Jaidah, Mohammed Y.; Bach, Steffen; Lee, Katie; Jabado, Rima W.; Rohner, Christoph A.; March, Abi; Caprodossi, Simone; Henderson, Aaron C.; Mair, James M.; Ormond, Rupert; Pierce, Simon J.

    2016-01-01

    Data on the occurrence of whale sharks, Rhincodon typus, in the Arabian Gulf and Gulf of Oman were collected by dedicated boat surveys and via a public-sightings scheme during the period from 2011 to 2014. A total of 422 individual whale sharks were photo-identified from the Arabian Gulf and the northern Gulf of Oman during that period. The majority of sharks (81%, n = 341) were encountered at the Al Shaheen area of Qatar, 90 km off the coast, with the Musandam region of Oman a secondary area of interest. At Al Shaheen, there were significantly more male sharks (n = 171) than females (n = 78; X2 = 17.52, P 9 m individuals were visually assessed as pregnant. Connectivity among sharks sighted in Qatari, Omani and UAE waters was confirmed by individual spot pattern matches. A total of 13 identified sharks were re-sighted at locations other than that at which they were first sighted, including movements into and out of the Arabian Gulf through the Strait of Hormuz. Maximum likelihood techniques were used to model an estimated combined population for the Arabian Gulf and Gulf of Oman of 2837 sharks ± 1243.91 S.E. (95% C.I. 1720–6295). The Al Shaheen aggregation is thus the first site described as being dominated by mature males while the free-swimming pregnant females are the first reported from the Indian Ocean. PMID:27362839

  11. The origin of islands in the Kandalaksha Gulf of the White Sea: joint work of internal and external geodynamic processes

    Science.gov (United States)

    Kosevich, Natalia; Romanovskaya, Maria

    2016-04-01

    The modern White Sea basin is a part of the encounter zone between the East European Platform and of the Fennoscandian Shield. The Kandalaksha Gulf in its northwest lies on the Mesoarchean-Paleoproterozoic structure known as the White Sea Shift Belt. In the Oligocene, it entered its neotectonic stage. Geologically, there are two structural storeys beneath the seafloor of the Kandalaksha Gulf: 1) crystalline bedrock of the Archean White Sea complex; 2) a cover of sediment consisting of three layers: Riphean sandstones, terrigenous Vendian deposits; a cloak of Pleistocene and Holocene deposits and sediments - glacial drifts, transitional glaciomarine sediments and purely marine sediments. The modern White Sea is a young basin formed just 10 to 12 ka. The geological and geomorphic history of the White Sea region was very complicated, with various and often conflicting tectonic movements. Besides the postglacial isostatic rise of Scandinavia amounted to some 100 meters in the White Sea area. The White Sea has numerous islands that are very different in the geological-geomorphological and genetic senses because their origin is the result of interactions between various endogenous and exogenous processes. Large and detailed scale geological and morphological researches of the islands at the southern and northern coast of the Kandalaksha Gulf have been carried out. Landforms of the islands were produced by the joint effects of such processes as (1) glacial-tectonic effects and marine wave action, (2) tidal and surge effects; (3) glacial-tectonic, marine, and gravity effects, and (4) glacial-tectonic, marine, lake, and biogenic effects (Kosevich, 2015). The relief structure of the islands has the following regularities: 1) structures of the northern coast islands are more often landforms that are composed of loose deposits with small sites of structural denudation residual outcrops; 2) the structures of the southern coast islands are typically combinations of loose

  12. Petroleum systems of the Malay Basin Province, Malaysia

    Science.gov (United States)

    Bishop, Michele G.

    2002-01-01

    The offshore Malay Basin province is a Tertiary oil and gas province composed of a complex of half grabens that were filled by lacustrine shales and continental clastics.These deposits were overlain by clastics of a large delta system that covered the basin.Delta progradation was interupted by transgressions of the South China Sea to the southeast, which finally flooded the basin to form the Gulf of Thailand.Oil and gas from the Oligocene to Miocene lacustrine shales and Miocene deltaic coals is trapped primarily in anticlines formed by inversion of the half grabens during the late Miocene.Hydrocarbon reserves that have been discovered amount to 12 billion barrels of oil equivalent.The U.S. Geological Survey assessment of the estimated quantities of conventional oil, gas and condensate that have the potential to be added to reserves by the year 2025 for this province is 6.3 billion barrels of oil equivalent (BBOE) (U. S. Geological Survey World Energy Assessment Team, 2000).

  13. Obesity, diabetes and longevity in the Gulf: is there a Gulf Metabolic Syndrome?

    OpenAIRE

    Guy, Geoffrey W.; Nunn, Alistair V.W.; Thomas, Louise E; Bell, Jimmy D.

    2009-01-01

    The Gulf is experiencing a pandemic of lifestyle-induced obesity and type 2 diabetes mellitus (T2DM), with rates exceeding 50 and 30%, respectively. It is likely that T2DM represents the tip of a very large metabolic syndrome iceberg, which precedes T2DM by many years and is associated with abnormal/ectopic fat distribution, pathological systemic oxidative stress and inflammation. However, the definitions are still evolving with the role of different fat depots being critical. Hormetic stimul...

  14. Pliocene-Quaternary contourites along the northern Gulf of Cadiz margin: sedimentary stacking pattern and regional distribution

    Science.gov (United States)

    Llave, Estefanía; Matias, Hugo; Hernández-Molina, F. Javier; Ercilla, Gemma; Stow, Dorrik A. V.; Medialdea, Teresa

    2011-12-01

    This study reports novel findings on the Pliocene-Quaternary history of the northern Gulf of Cadiz margin and the spatiotemporal evolution of the associated contourite depositional system. Four major seismic units (P1, P2, QI and QII) were identified in the Pliocene-Quaternary sedimentary record based on multichannel seismic profiles. These are bounded by five major discontinuities which, from older to younger, are the M (Messinian), LPR (lower Pliocene revolution), BQD (base Quaternary discontinuity), MPR (mid-Pleistocene revolution) and the actual seafloor. Unit P1 represents pre-contourite hemipelagic/pelagic deposition along the northern Gulf of Cadiz margin. Unit P2 reflects a significant change in margin sedimentation when contourite deposition started after the Early Pliocene. Mounded elongated and separated drifts were generated during unit QI deposition, accompanied by a general upslope progradation of drifts and the migration of main depocentres towards the north and northwest during both the Pliocene and Quaternary. This progradation became particularly marked during QII deposition after the mid-Pleistocene (MPR). Based on the spatial distribution of the main contourite depocentres and their thickness, three structural zones have been identified: (1) an eastern zone, where NE-SW diapiric ridges have controlled the development of two internal sedimentary basins; (2) a central zone, which shows important direct control by the Guadalquivir Bank in the south and an E-W Miocene palaeorelief structure in the north, both of which have significantly conditioned the basin-infill geometry; and (3) a western zone, affected in the north by the Miocene palaeorelief which favours deposition in the southern part of the basin. Pliocene tectonic activity has been an important factor in controlling slope morphology and, hence, influencing Mediterranean Outflow Water pathways. Since the mid-Pleistocene (MPR), the sedimentary stacking pattern of contourite drifts has been

  15. Late Glacial to Holocene evolution and sea-level history of Gulf of Gemlik, Sea of Marmara, Turkey

    Science.gov (United States)

    Sabuncu, Asen; Kadir Eriş, K.; Kaslilar, Ayse; Namık Çaǧatay, M.; Gasperini, Luca; Filikçi, Betül

    2016-04-01

    The Gulf of Gemlik is an E-W elongated trans-tensional basin with a maximum depth of 113 m, located on the middle strand of the North Anatolian Fault (NAF) in the south eastern part of the Sea of Marmara (SoM). While during the Holocene the sea level in the Gulf of Gemlik changed in tandem with the water level changes in the SoM, it may have been different in the late glacial when the Sea of Marmara was lacustrine. Beside the tectonic activity related to the NAFZ, eustatic sea level changes would have controlled the basin evolution and consequent sedimentary history during the different paleocanographic phases of the SoM. Considering the limited studies on the late glacial-Holocene stratigraph of the Gulf of Gemlik, this study aims to investigate the depositional units and their environments with respect to different allogenic and autogenic controls. For these purposes, we analyzed over 300 2 - 7 kHz bandwidth high-resolution gridded seismic sub-bottom CHIRP profiles together with 70 kHz high resolution multibeam bathymetry with backscatter data. Four seismic stratigraphic units were defined and correlated with chronstratigraphic units in five piston cores covering the last 15.8 ka BP according to radiocarbon ages (14C). The depth-scale accuracy of chronostratigraphic units in cores is of key importance for the precise calculation of sedimentation rates. Correlation between the seismic profiles and cores were made by matching Multi-Sensor Core-Logger (MSCL) data and seismic reflection coefficients and amplitudes for different stratigraphic units. The impedance data derived from the logger were used to generate a synthetic seismogram. We used an approach to display, estimate, and correct the depth-scale discrepancies due to oversampling affecting the upper part of sedimentary series during piston coring. The method is based on the resynchronization of synthetic seismograms computed from high-quality physical property logs to the corresponding CHIRP profiles. Each

  16. Evolution of Surface Water Conditions in the Gulf of California During the Past 2000 years: Implications for the North American Monsoon

    Science.gov (United States)

    Barron, J. A.; Bukry, D.; Addison, J. A.; McGann, M.; Schwartz, V.; McGeehin, J. P.; McClymont, E.

    2015-12-01

    High-resolution analyses of diatoms, silicoflagellates, biogenic silica, and alkenones in laminated sediment cores from the Guaymas Basin (central Gulf of California) reveal pronounced changes in surface water conditions over the past 2000 years. Prior to ~AD 1200, surface waters in the western Guaymas Basin (boxcore MD02-2517c2 at 27.4850° N, 112.0743°W, water depth 887 m) were characterized by high biologic productivity with alternating assemblages of productive diatoms (Thalassionema nitzschioides, Fragilariopsis doliolus) and silicoflagellates (Octactis pulchra, Dictyocha stapedia). Beginning at ~ AD 1200 productivity declined abruptly in two steps (at ~AD 1200 and ~1500) that were marked by increases in the relative abundance of tropical diatoms and silicoflagellates. In contrast, eastern Guaymas Basin Kasten Core BAM80 E-17 (27.920° N, 111.610°W, 620 m of water depth), was dominated by high biosiliceous productivity during the past 2000 years with increases corresponding to solar minima, arguing that an intensification of winter northwest winds drove coastal upwelling. In both Guaymas Basin records silicoflagellate assemblages suggest surface-water cooling during Medieval Climate Anomaly (MCA; ~AD 800-1200) relative to the intervals before and after. Together, these records support a cooler La Niña-like MCA followed by a warmer El Niño-like Little Ice Age, similar to results obtained from the Santa Barbara Basin to the north. During La Niñas, the Intertropical Convergence Zone (ITCZ) occupies a more northerly position in the eastern tropical Pacific, facilitating summertime surges of Pacific tropical moisture up the Gulf and higher monsoonal precipitation in the southwestern US. A modeling study by Song Feng et al. (2008, JGR) of the broader MCA (AD 800-1300) utilizes La Niña-like Pacific sea surface temperatures to argues for an intensified North American Monsoon during the MCA. Limited terrestrial proxy records from Arizona and New Mexico are

  17. New era in Gulf of Mexico seismic

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, H.; Brune, R. [TGS-Calibre Geophysical Co., Houston, TX (United States)

    1996-05-01

    The 1990s have seen tremendous changes in seismic activity in the Gulf of Mexico (GOM). Until the 1980s, seismic surveys in the GOM, particularly 3-D, were almost always proprietary. From 1990 to 1993, activity shifted so that now nearly all seismic surveys are non-exclusive 3-D, available for license by any operator. An obvious motivation for this shift was the reduced costs to E and P companies. Technical reasons also motivated this shift. Larger surveys have halos sufficient to image steeper dips and deeper targets, and allow analysis of complex regional geologic settings. This paper briefly summarizes the new technologies, trends in 3-D usage, ocean bottom cabling, data processing, data quality, and navigational tracking systems.

  18. Directional wave measurements off Navinal, Gulf of Kachchh, India

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; KrishnaKumar, V.; Suryanarayana, A.; Antony, M.K.; Swamy, G.N.

    Results of directional wave measurements carried out off Navinal, Gulf of Kachchh representing pre-monsoon and southwest monsoon wave conditions are presented. Maximum wave height encountered during pre-monsoon and southwest monsoon is 1.36 and 1...

  19. Gulf sturgeon Critical Habitat Units 1-7

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Gulf Sturgeon as designated by Federal Register Vol. 68, No. 53, Wednesday, March 19, 2003, Rules and Regulations.

  20. Gulf of Mexico Marine Mammal Assessment Vessel Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets are a compilation of large vessel surveys for marine mammal stock assessments in the Gulf of Mexico from 1991 to the present. These are designed as...

  1. Gulf of Maine Cooperative Bottom Longline Survey Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database is for a bottom longline (fixed gear) survey executed in the western and central Gulf of Maine targeting complex rocky habitats. The survey is...

  2. EAARL Topography-Gulf Islands National Seashore-Florida

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed, geographically-referenced...

  3. Gulf of Mexico sperm whale photo-ID catalog

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Photo-identification data on sperm whales occupying the north central Gulf of Mexico have been collected during vessel surveys. Photographs of sperm whales are...

  4. Narrative report: Gulf Island National Wildlife Refuges: 1966

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Gulf Island National Wildlife Refuges (Petit Bois National Wildlife Refuge, Horn Island National Wildlife Refuge, and Breton...

  5. Water Density Raster Images for the Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This geodatabase contains water density raster images for the Gulf of Maine that were interpolated from water density (sigma t or kilograms/ meters cubed) point...

  6. Water Stratification Raster Images for the Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This geodatabase contains seasonal water stratification raster images for the Gulf of Maine. They were created by interpolating water density (sigma t) values at 0...

  7. Mercury levels in seabirds in the Gulf of Maine

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We conducted a pilot study to screen mercury (Hg) levels in Gulf of Maine seabirds in an effort to determine which species are most at risk, are the most...

  8. Piram island: Pirates Fort in the Gulf of Khambat

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A; Bhatt, B.K.

    Traditionally, Piram Island has been considered as landmark point for the navigators in the Gulf of Cambay. The mention has also been made that Island has served as heaven for pirates. A coastal archaeological exploration was undertaken in order...

  9. The role of the Gulf Stream in European climate.

    Science.gov (United States)

    Palter, Jaime B

    2015-01-01

    The Gulf Stream carries the warm, poleward return flow of the wind-driven North Atlantic subtropical gyre and the Atlantic Meridional Overturning Circulation. This northward flow drives a significant meridional heat transport. Various lines of evidence suggest that Gulf Stream heat transport profoundly influences the climate of the entire Northern Hemisphere and, thus, Europe's climate on timescales of decades and longer. The Gulf Stream's influence is mediated through feedback processes between the ocean, atmosphere, and cryosphere. This review synthesizes paleoclimate archives, model simulations, and the instrumental record, which collectively suggest that decadal and longer-scale variability of the Gulf Stream's heat transport manifests in changes in European temperature, precipitation, and storminess. Given that anthropogenic climate change is projected to weaken the Atlantic Meridional Overturning Circulation, associated changes in European climate are expected. However, large uncertainty in the magnitude of the anticipated weakening undermines the predictability of the future climate in Europe.

  10. Narrative report: Gulf Island National Wildlife Refuges: 1964

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Gulf Island National Wildlife Refuges (Petit Bois National Wildlife Refuge, Horn Island National Wildlife Refuge, and Breton...

  11. Narrative report: Gulf Island National Wildlife Refuges: 1965

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Gulf Island National Wildlife Refuges (Petit Bois National Wildlife Refuge, Horn Island National Wildlife Refuge, and Breton...

  12. Narrative report: Gulf Island National Wildlife Refuges: 1967

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Gulf Island National Wildlife Refuges (Petit Bois National Wildlife Refuge, Horn Island National Wildlife Refuge, and Breton...

  13. Narrative report: Gulf Island National Wildlife Refuges: 1968

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Gulf Island National Wildlife Refuges (Petit Bois National Wildlife Refuge, Horn Island National Wildlife Refuge, and Breton...

  14. 2009 Survey of Gulf of Mexico Dockside Seafood Processors

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This survey gathered and analyze economic data from seafood processors throughout the states in the Gulf region. The survey sought to collect financial variables...

  15. EAARL Topography-Gulf Islands National Seashore-Mississippi

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Abstract: Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed,...

  16. Gulf of Mexico Kemps ridley sea turtle age and growth

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study involves analysis of skeletal growth marks in humerus bones of 340 Kemps ridley sea turtles stranded dead along the Gulf of Mexico US coast (hatchling to...

  17. Shipping Fairways in the Gulf of Mexico, from BOEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Polygon data for all major shipping lanes associated with all ports in the Gulf of Mexico are presented. These layers were modified from GIS data acquired from the...

  18. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: First surface

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first surface elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  19. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  20. Gulf of Mexico Marine Mammal Vessel Surveys - NRDA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large vessel surveys were conducted during June-August and Oct-Nov, 2010 in the north central Gulf of Mexico to collect data on marine mammal spatial distribution...

  1. Gulf of Mexico killer whale photo-ID catalog

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Photo-identification data on killer whales occupying the northern Gulf of Mexico have been collected in association with large vessel surveys since 1991....

  2. 2012 Economic Survey of Gulf State Shrimp License Holders

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This mail survey collected economic data on inshore commercial shrimp fishermen who held licenses to commercially harvest shrimp in state waters of the U.S. Gulf of...

  3. Gulf of Maine Contaminated Sediments Database (GOMCSDB shapefile)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Contaminated Sediments Database for the Gulf of Maine provides a compilation and synthesis of existing data to help establish the environmental status of our...

  4. Gulf of Mexico Regional Climatology (NCEI Accession 0123320)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Gulf of Mexico Regional Climatology is a set of objectively analyzed climatological fields of temperature, salinity, oxygen, phosphate, silicate, and nitrate at...

  5. Northern Gulf of Mexico Marine Mammal Unusual Mortality Event Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Tissues and samples collected from marine mammals during investigation of the Northern Gulf of Mexico Marine Mammal Unusual Mortality Event are tracked within this...

  6. Gulf of Mexico Protected Species Assessment Aerial Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets include a compilation of aerial line-transect surveys conducted over continental shelf waters of the Gulf of Mexico since 1992. The majority of...

  7. Gulf of Mexico Sperm Whale Acoustic Prey Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large vessel surveys were conducted during the summer of 2009 and the winter of 2010 in the north-central Gulf of Mexico to examine the spatial distribution of...

  8. Gulf sturgeon Critical Habitat Units 8-14

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Gulf Sturgeon as designated by Federal Register Vol. 68, No. 53, Wednesday, March 19, 2003, Rules and Regulations.

  9. Wind Simulations for the Gulf of Suez with KAMM

    DEFF Research Database (Denmark)

    Frank, Helmut Paul

    In order to get a better overview of the spatial distribution of the wind resource in the Gulf of Suez, numerical simulations to determine the wind climate have been carried out with the Karlsruhe Atmospheric Mesoscale Model KAMM. The method and the results are described here. The simulations of ...... of the wind climate of the Gulf of Suez with KAMM capture the main features of the observed wind climate. The mean wind speed and energy flux density are somewhat underpredicted....

  10. Carnosine Treatment for Gulf War Illness: A Randomized Controlled Trial

    OpenAIRE

    Baraniuk, James Nicholas; El-Amin, Suliman; Corey, Rebecca; Rayhan, Rakib; Timbol, Christian

    2013-01-01

    About 25% of 1990-1991 Persian Gulf War veterans experience disabling fatigue, widespread pain, and cognitive dysfunction termed Gulf War illness (GWI) or Chronic Multisymptom Illness (CMI). A leading theory proposes that wartime exposures initiated prolonged production of reactive oxygen species (ROS) and central nervous system injury. The endogenous antioxidant L-carnosine (β-alanyl-L-histidine) is a potential treatment since it is a free radical scavenger in nervous tissue. To determine if...

  11. The Neolithic origins of seafaring in the Arabian Gulf

    Directory of Open Access Journals (Sweden)

    Robert Carter

    2002-10-01

    Full Text Available The inhabitants of the Arabian Gulf were among the world’s earliest maritime traders. Their ships sailed regularly between the Bronze Age civilizations of Mesopotamia, Bahrain and the Indus Valley, and they reached China by sea in the eighth century AD, thus bypassing the long and perilous overland Silk Road route across Central Asia. Now excavations at a coastal site in Kuwait by a team from the Institute have revealed even earlier evidence of maritime activity in the Gulf.

  12. Sperm whales (Physeter catodon) in the Gulf of Mexico

    Science.gov (United States)

    Collum, L.A.; Fritts, T.H.

    1985-01-01

    The distribution of the sperm whale, Physeter catodon, was documented in the Gulf of Mexico during 1979 to 1981 using regular aerial surveys and opportunistic sightings from ships. Most sightings were in the western Gulf of Mexico in deep waters near the edge of the continental shelf. A total of 47 adults and 12 young animals was sighted in groups containing from one to 14 animals.

  13. Study on artificial island port in Beibu gulf

    OpenAIRE

    Jinrong, A.M.; Yaqiong, B.G.; Kunqiang, C.L.; Zhimin, D.W.

    2013-01-01

    Regarding preservation and development of coast, artificial island port has been concerned for years by the government of Guangxi province which locates in the north coast of Beibu gulf in China. The nature conditions are suitable to build ports for the semi-closed gulf and curvilinear bays. There are three main port bays in Guangxi province named as Fangcheng, Qinzhou, and Tieshan. The former two bays have developed almost all the deepwater shoreline into docks. With many land reclamation pr...

  14. Chronology and dynamics of the Amundsen Gulf Ice Stream in Arctic Canada during the last glacial-interglacial transition

    Science.gov (United States)

    Lakeman, T. R.; MacLean, B.; Blasco, S.; Bennett, R.; Hughes Clarke, J. E.

    2012-04-01

    influence of the Mackenzie and other fluvial sediment discharge on the seabed over the last 13,000 cal yr BP. The deglacial history of Amundsen Gulf under ameliorating climate conditions of the last ~19,000 cal yr BP provides important constraints on the variables that occasioned the demise of the northwest Laurentide Ice Sheet, such as sea level change, paleoclimate, and regional ice sheet dynamics. Understanding the complex interplay among these variables during the last deglaciation will bear on current model projections of the dynamics of the Greenland and Antarctic ice sheets. In addition, quantifying past iceberg fluxes to the Arctic Ocean has implications for assessing the origin of deep ice scours in the Arctic Ocean Basin and the nature of rapid climate changes at the last glacial-interglacial transition.

  15. Evolution and timing of salt diapirism in the Iranian sector of the Persian Gulf

    Science.gov (United States)

    Perotti, Cesare; Chiariotti, Luca; Bresciani, Ilenia; Cattaneo, Luciano; Toscani, Giovanni

    2016-06-01

    The Iranian sector of the Persian Gulf is affected by more than 30 large diapiric structures triggered by the mobilization of the Infracambrian Hormuz Complex, an evaporite-rich unit that overlies Precambrian basement at the base of the sedimentary succession. Nineteen non-piercing diapirs, without any appreciable salt intrusion into the upper succession, were studied in detail and retro-deformed by the decompaction and unfolding of 13 seismic horizons that were identified by the interpretation of a dense grid of 2D seismic lines and calibrated by well data. Salt uplift had begun by the Early Palaeozoic and persists to the present day, with major pulses of intensity during the Middle Triassic, Cenomanian, Late Oligocene, and post-Middle Miocene. The structural reconstructions and the analysis of the progressive deformation of the study diapirs do not show any link between diapiric uplift and local tectonic structures, and no clear correlation with the regional geodynamic events acting at the boundary of the Arabian plate. On the contrary, the salt uplift seems strongly influenced by the differential rate of sedimentation that affected the whole study basin (more than 40,000 km2), with a coefficient of correlation between the salt uplift rate and the differential rate of sedimentation (expressed by the standard deviation of the sedimentation rate calculated over the entire basin) of 0.95. This downbuilding mechanism of diapiric growth is apparently induced by differential sedimentation over long distances (several tens of kilometers), showing that the flow of salt affected the whole basin and not just the areas around the single diapiric structures.

  16. Modifed Great Basin Extent (Buffered)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Two different great basin perimeter files were intersected and dissolved using ArcGIS 10.2.2 to create the outer perimeter of the great basin for use modeling...

  17. Grain size distribution, clay mineralogy and chemistry of bottom sediments from the outer Thermaikos Gulf, Aegean Sea, Greece

    Directory of Open Access Journals (Sweden)

    K.G. PEHLIVANOGLOU

    2012-12-01

    Full Text Available The Thermaikos Gulf constitutes the NW part of the North Aegean Sea and is limited eastward from the Chalkidiki Peninsula and westward from the Pieria Prefecture. Its plateau covers an area of 3,500 km2. The mechanisms responsible for the grain size distribution into the Gulf, the clay mineralogy and the chemistry of some bottom sediments from the outer Thermaikos Gulf, are examined. Source mixing during transportation, flocculation, differential settling processes and organic matter appear to be the main mechanisms for the distribution of clay minerals in shallow waters. All grain size fractions studied present a wide range of values confirming the extreme variations of the discharged load and the variability in marine processes. Plagioclases predominate over K-feldspars, while quartz is the most abundant mineral present. In addition, micas, chlorites, amphiboles and pyroxenes exist as primary and/or accessory minerals in all samples. Among clay minerals, illite predominates over smectite and smectite over chlorite (+ kaolinite. The ordered interstratified phase of I/S, with 30-35% S layers, is present in the 2-0.25µm fraction. The randomly interstratified phase of I/S, with 50% S layers, is present in the <0.25& micro; m fraction. On average the clay mineral content of the studied samples is: 48% I, 23% S, 17% Ch (+K and 12% others for the 2-0.25µm fraction and 50% I, 30% S and 20% Ch (+K for the <0.25 µm fraction. All these minerals are the weathering products of the rocks from the drainage basins of the rivers flowing into the Gulf, as well as of the Neogene and Quaternary unconsolidated sediments of the surrounding coasts. The terrigenous input, the water mass circulation and, to a lesser extent, the quality of the discharged material and the differential settling of grains, control the grain size distribution within the outer Thermaikos Gulf. The chemical composition of the analysed samples is generally in agreement with their mineral

  18. Oil spill in the Gulf of Mexico and spiral vortex

    Institute of Scientific and Technical Information of China (English)

    ZHENG Quanan; ZHAO Qing; Nan Walker; LI Chunyan

    2010-01-01

    @@ Drilling rig Decpwater Horizon in the Gulf of Mexico, leased by BP PLC from Transocean Ltd., ex-ploded and caught on fire on April 20, 2010. The drilling location is at some 50 miles (80 kilometers) off the coast of Louisiana, USA. The rig sank on April 22. Since then, oil has been pouring into the Gulf from the blown-out undersea well. As reported by US Today and Calgary Herald on July 3, an estimated 35 000 to 60 000 barrels of oil per day has been gush-ing out of the ruptured well into the Gulf. That means amounts to a total of 1.9 to 3.6 million barrels of oil so far have gushed into the Gulf. Using the high end of that estimate, the spill has now surpassed the 1979 Ixtoc blowout, which took nine months to cap and dumped estimated 3.3 million barrels (140 000 million gallons) into the Gulf of Mexico. It is topped only by the deliberate release of six to eight million barrels of crude oil by Iraqi troops who destroyed tankers and oil terminals and set wells ablaze in Kuwait during the 1991 Gulf War.

  19. Influence of the Gulf Stream on the troposphere.

    Science.gov (United States)

    Minobe, Shoshiro; Kuwano-Yoshida, Akira; Komori, Nobumasa; Xie, Shang-Ping; Small, Richard Justin

    2008-03-13

    The Gulf Stream transports large amounts of heat from the tropics to middle and high latitudes, and thereby affects weather phenomena such as cyclogenesis and low cloud formation. But its climatic influence, on monthly and longer timescales, remains poorly understood. In particular, it is unclear how the warm current affects the free atmosphere above the marine atmospheric boundary layer. Here we consider the Gulf Stream's influence on the troposphere, using a combination of operational weather analyses, satellite observations and an atmospheric general circulation model. Our results reveal that the Gulf Stream affects the entire troposphere. In the marine boundary layer, atmospheric pressure adjustments to sharp sea surface temperature gradients lead to surface wind convergence, which anchors a narrow band of precipitation along the Gulf Stream. In this rain band, upward motion and cloud formation extend into the upper troposphere, as corroborated by the frequent occurrence of very low cloud-top temperatures. These mechanisms provide a pathway by which the Gulf Stream can affect the atmosphere locally, and possibly also in remote regions by forcing planetary waves. The identification of this pathway may have implications for our understanding of the processes involved in climate change, because the Gulf Stream is the upper limb of the Atlantic meridional overturning circulation, which has varied in strength in the past and is predicted to weaken in response to human-induced global warming in the future.

  20. Anthropogenic and authigenic uranium in marine sediments of the central Gulf of California adjacent to the Santa Rosalía mining region

    OpenAIRE

    Shumilin, Evgueni; Rodríguez Figueroa, Griselda Margarita; Sapozhnikov, Dmitry; Sapozhnikov, Yuri; Choumiline, Konstantin

    2012-01-01

    To investigate the causes of uranium (U) enrichment in marine sediments in the eastern sector of the Gulf of California, surface sediments and sediment cores were collected adjacent to the Santa Rosalı´a copper mining region in the Baja California peninsula. Three coastal sediment cores were found to display high concentrations of U (from 54.2 ± 7.3 mg kg-1 to 110 ± 13 mg kg-1) exceeding those found in the deeper cores (1.36 ± 0.26 mg kg-1 in the Guaymas Basin to 9.31 ± 3.03 mg kg-1 in the SR...

  1. 76 FR 43250 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Stone Crab Fishery of the Gulf of...

    Science.gov (United States)

    2011-07-20

    ... action is to enhance the effectiveness and efficiency of managing the stone crab fishery in the Gulf of... Microsoft Word, Excel, WordPerfect, or Adobe PDF file formats only. Comments received through means...

  2. Geology Arc Export Layer From Coal Bearing Geology of the Gulf Coast Coal Region (gulf_geol_dd.e00)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is a polygon vector coverage of coal bearing geologic units that occur in states which comprise the Gulf Coast Coal Assessment Region as defined by the...

  3. Reversing the indus basin closure

    OpenAIRE

    2011-01-01

    After independence, a swift and extensive development of Indus river basin has intensified commitment of water resources. During dry period, the indication of over commitment and basin closure are visible. In the beginning 2000s, he river basin water resources were committed to more than 99% without any environmental flows. The paper tries to unfold drivers closing the Indus basin and the scope for change. Defining and implementing water allocation mechanism to ascertain equity, sustainabilit...

  4. Final report on Paradox Basin/Gulf Interior: Regulatory project management

    International Nuclear Information System (INIS)

    This final report on the Regulatory Project Manager (RPM) program begins with a discussion of the key products produced during the 9-year effort and then focuses on the work performed in the major disciplines. The report then discusses the management of the work effort and the Quality Assurance (QA) program. It concludes with a brief discussion of the records turned over to the Office of Nuclear Waste Isolation (ONWI) at the conclusion of the work. 14 figs., 14 tabs

  5. Single-basined choice

    NARCIS (Netherlands)

    Bossert, W.; Peters, H.J.M.

    2013-01-01

    Single-basined preferences generalize single-dipped preferences by allowing for multiple worst elements. These preferences have played an important role in areas such as voting, strategy-proofness and matching problems. We examine the notion of single-basinedness in a choice-theoretic setting. In co

  6. The Mediterranean basin

    DEFF Research Database (Denmark)

    Tomas, Carmen; Sanchez Sanchez, Juan Jose; Barbaro, A.;

    2008-01-01

    genetically from the rest of the populations in the Mediterranean area. This result supports the hypothesis of a low incidence of the south-north genetic interchange at the western shores of the Mediterranean basin. A low genetic distance was found between populations in the Middle East and the western part...

  7. Gulf Coast Programmatic Environmental Assessment Geothermal Well Testing: The Frio Formation of Texas and Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-10-01

    In accordance with the requirements of 10 CFR Part 711, environmental assessments are being prepared for significant activities and individual projects of the Division of Geothermal Energy (DGE) of the Energy Research and Development Administration (ERDA). This environmental assessment of geopressure well testing addresses, on a regional basis, the expected activities, affected environments, and possible impacts in a broad sense. The specific part of the program addressed by this environmental assessment is geothermal well testing by the take-over of one or more unsuccessful oil wells before the drilling rig is removed and completion of drilling into the geopressured zone. Along the Texas and Louisiana Gulf Coast (Plate 1 and Overlay) water at high temperatures and high pressures is trapped within Gulf basin sediments. The water is confined within or below essentially impermeable shale sequences and carries most or all of the overburden pressure. Such zones are referred to as geopressured strata. These fluids and sediments are heated to abnormally high temperatures (up to 260 C) and may provide potential reservoirs for economical production of geothermal energy. The obvious need in resource development is to assess the resource. Ongoing studies to define large-sand-volume reservoirs will ultimately define optimum sites for drilling special large diameter wells to perform large volume flow production tests. In the interim, existing well tests need to be made to help define and assess the resource. The project addressed by this environmental assessment is the performance of a geothermal well test in high potential geothermal areas. Well tests involve four major actions each of which may or may not be required for each of the well tests. The four major actions are: site preparation, drilling a salt-water disposal well, actual flow testing, and abandonment of the well.

  8. Oceanic and climatic drivers of mangrove changes in the Gulf of Urabá, Colombian Caribbean

    Directory of Open Access Journals (Sweden)

    July A Suárez

    2015-11-01

    Full Text Available The Gulf of Uraba is the largest estuary on the Caribbean coast of Colombia. The aim of this research was to analyse the oceanic, climatic and environmental variables that influence mangrove structure and composition in the gulf. Based on the availability of remote sensing, the study area was divided into western and eastern zones. The spatial pattern of environmental variables (water salinity, pH and percentage of organic matter, sand, silt and clay in the soils and oceanic and climatic variables (winds, wave height and wave period was analysed. The relationship of these variables with variables of vegetation structure (basal area, diameter at breast height, tree height, and abundance of seedlings of mangrove species in 1 m² subplots was analysed in 27 plots of 500 m² containing fringe mangroves and 5 plots containing basin mangroves. Mangroves of the western zone showed a higher structural development and were dominated by Rhizophora mangle (red mangrove. This zone is supplied by fresh water and sediments, and the soils have a high content of organic matter and clay and a low degree of anthropogenic disturbance. The eastern zone was characterized by higher pore water salinity due to lower freshwater input from rivers. In this area there is a smaller impact of waves and winds, higher sedimentation rates, high anthropogenic disturbance and mangroves are dominated by Avicennia germinans (black mangrove. Although Laguncularia racemosa (white mangrove did not show a particular spatial pattern, due to its tolerance to open canopy conditions it was commonly found in anthropogenically disturbed areas.

  9. Hydrocarbons in surface sediments from a Guaymas Basin hydrothermal vent site. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Bazylinski, D.A.; Farrington, J.W.; Jannasch, H.W.

    1988-01-01

    Petroleum-like materials found at the Guaymas Basin hydrothermal vent site (Gulf of California) are derived from pyrolysis of organic matter. Two characteristics surface sediment cores differing in temperature profiles and other parameters were collected by DSV ALVIN, sectioned, and analyzed for hydrocarbons. The quantitative and qualitative composition of alkanes, steranes, diasteranes, and triterpanes differed between these cores as well as within sections of the same core. These differences, apparent for scales of tens of centimeters, are related to interactive physical, chemical, and microbial processes as well as the influence of multiple sources for the petroleum.

  10. Hydrocarbons in surface sediments from a Guaymas Basin hydrothermal vent site

    Energy Technology Data Exchange (ETDEWEB)

    Bazylinski, D.A.; Farrington, J.W.; Jannasch, H.W. (Woods Hole Oceanographic Institution, Woods Hole, MA (USA))

    1988-01-01

    Petroleum-like materials found at the Guaymas Basin hydrothermal vent site (Gulf of California) are derived from pyrolysis of organic matter. Two characteristic surface sediment cores differing in temperature profiles and other parameters were collected by DSV ALVIN, sectioned and analyzed for hydrocarbons. The quantitative and qualitative composition of alkanes, steranes, diasteranes, and triterpanes differed between these cores as well as within sections of the same core. These differences, apparent for scales of tens of centimeters, are related to interactive physical, chemical, and microbial processes as well as the influence of multiple sources for the petroleum.

  11. Bransfield Basin and Cordilleran Orogenesis

    Science.gov (United States)

    Dalziel, I. W.; Austin, J. A.; Barker, D. H.; Christensen, G. L.

    2003-12-01

    Tectonic uplift of the Andean Cordillera was initiated in the mid-Cretaceous with inversion of a composite marginal basin along 7500 km of the continental margin of South America, from Peru to Tierra del Fuego and the North Scotia Ridge. In the southernmost Andes, from 50-56 degrees S, the quasi-oceanic floor of this basin is preserved in the obducted ophiolitic rocks of the Rocas Verdes (Green Rocks) basin. We suggest that the basin beneath Bransfield Strait, 61-64 degrees S, separating the South Shetland Islands from the Antarctic Peninsula, constitutes a modern analog for the Rocas Verdes basin. Marine geophysical studies of Bransfield basin have been undertaken over the past 12 years by the Institute for Geophysics, University of Texas at Austin, under the auspices of the Ocean Sciences Division and United States Antarctic Program, National Science Foundation. These studies have elucidated the structure and evolution of Bransfield basin for comparison with the Rocas Verdes basin, with a view to eventual forward modeling of the evolution of a hypothetical cordilleran orogen by compression and inversion of the basin. These are the processes that can be observed in the tectonic transformation of the Rocas Verdes basin into the southernmost Andean cordillera, as South America moved rapidly westward in an Atlantic-Indian ocean hot-spot reference frame during the mid-Cretaceous. Multi-channel reflection seismic data from the Bransfield basin reveal an asymmetric structural architecture characterized by steeply-dipping normal faults flanking the South Shetlands island arc and gently dipping listric normal faults along the Antarctic Peninsula margin. Normal fault polarity reversals appear to be related to distributed loci of magmatic activity within the basin. This architecture is remarkably similar to that deduced from field structural studies of the Rocas Verdes basin. Notably, the oceanward-dipping, low angle normal faults along the Antarctic Peninsula margin

  12. Seismic Activity in the Gulf of Mexico: a Preliminary Analysis

    Science.gov (United States)

    Franco, S. I.; Canet, C.; Iglesias, A.; Valdes-Gonzales, C. M.

    2013-05-01

    The southwestern corner of Gulf of Mexico (around the northern Isthmus of Tehuantepec) is exposed to an intense deep (> 100 km) seismic activity caused by the subduction of the Cocos plate. Aside from this, the gulf has been considered as a zone of low or no-seismicity. However, a sparse shallow seismic activity is observed across the Gulf of Mexico; some of these earthquakes have been strongly felt (e.g. 23/05/2007 and 10/09/2006), and the Jaltipan, 1959 earthquake caused fatalities and severe destruction in central and southern Veracruz. In this work we analyze 5 relevant earthquakes that occurred since 2001. At the central Gulf of Mexico focal mechanisms show inverse faults oriented approximately NW-SE with dip near 45 degrees, suggesting a link to sediment loading and/or to salt tectonics. On the other hand, in the southwestern corner of the gulf we analyzed some clear examples of strike-slip faults and activity probably related to the Veracruz Fault. One anomalous earthquake, recorded in 2007 in the western margin of the gulf, shows a strike-slip mechanism indicating a transform regime probably related with the East Mexican Fault. The recent improvement of the Mexican Seismological broadband network have allowed to record small earthquakes distributed in and around the Gulf of Mexico. Although the intermediate and large earthquakes in the region are infrequent, the historic evidence indicates that the magnitudes could reach Mw~6.4. This fact could be taken in consideration to reassess the seismic hazard for oil and industrial infrastructure in the region.

  13. Salinity Measurements During the Gulf Stream Experiment

    Science.gov (United States)

    LeVine, D. M.; Koblinsky, C.; Howden, S.; Goodberlet, M.

    2000-01-01

    The salinity of the open ocean is important for understanding ocean circulation, for understanding energy exchange with the atmosphere and for improving models to predict weather and climate. Passive microwave sensors at L-band (1.4 GHz) operating from aircraft have demonstrated that salinity can be measured with sufficient accuracy (1 psu) to be scientifically meaningful in coastal waters. However, measuring salinity in the open ocean presents unresolved issues largely because of the much greater accuracy (approx. 0.1 psu) required to be scientifically viable. In the summer of 1999 a series of measurements called, The Gulf Stream Experiment, were conducted as part of research at the Goddard Space Flight Center to test the potential for passive microwave remote sensing of salinity in the open ocean. The measurements consisted of a compliment of airborne microwave instruments (radiometers and scatterometer) and ships and drifters for surface truth. The study area was a 200 km by 100 km rectangle about 250 km east of Delaware Bay between the continental shelf waters and north wall of the Gulf Stream. The primary passive instruments were the ESTAR radiometer (L-band, H-pol) and the SLFMR radiometer (L-band, V-pol). In addition, the compliment of instruments on the aircraft included a C-band radiometer (ACMR), an ocean wave scatterometer (ROWS) and an infrared radiometer. A GPS backscatter experiment was also part of the package. These instruments were mounted on the NASA P-3 Orion aircraft. Surface salinity measurements were provided by the RN Cape Henlopen and MN Oleander (thermosalinographs) plus salinity and temperature sensors on three surface drifters deployed from the RN Cape Henopen. The primary experiment period was August 26-September 2, 1999. During this period the salinity field within the study area consisted of a gradient on the order of 2-3 psu in the vicinity of the shelf break and a warm core ring with a gradient of 1-2 psu. Detailed maps were made

  14. Rapid ventilation of the Mexico City basin and regional fate of the urban plume

    Directory of Open Access Journals (Sweden)

    B. de Foy

    2006-01-01

    Full Text Available Urban areas can be large emitters of air pollutants leading to negative health effects and environmental degradation. The rate of venting of these airsheds determines the pollutant loading for given emission levels, and also determines the regional impacts of the urban plume. Mexico City has approximately 20 million people living in a high altitude basin with air pollutant concentrations above the health limits most days of the year. A mesoscale meteorological model (MM5 and a particle trajectory model (FLEXPART are used to simulate air flow within the Mexico City basin and the fate of the urban plume during the MCMA-2003 field campaign. The simulated trajectories are validated against pilot balloon and radiosonde trajectories. The residence time of air within the basin and the impacted areas are identified by episode type. Three specific cases are analysed to identify the meteorological processes involved. For most days, residence times in the basin are less than 12 h with little carry-over from day to day and little recirculation of air back into the basin. Very efficient vertical mixing leads to a vertically diluted plume which, in April, is transported predominantly towards the Gulf of Mexico. Regional accumulation was found to take place for some days however, with urban emissions sometimes staying over Mexico for more than 6 days. Knowledge of the residence times, recirculation patterns and venting mechanisms will be useful in guiding policies for improving the air quality of the MCMA.

  15. Multi-approach quantification of denudation rates in the Gulf of Lion source-to-sink system (SE France)

    Science.gov (United States)

    Molliex, S.; Rabineau, M.; Leroux, E.; Bourlès, D. L.; Authemayou, C.; Aslanian, D.; Chauvet, F.; Civet, F.; Jouët, G.

    2016-06-01

    During the Pliocene and the Quaternary, the Gulf of Lion, the northern passive margin of the Liguro-Provençal basin in the western Mediterranean Sea, received sediments from a 120 000 km2 drainage area constituted by several structural domains. The denudation of mountainous areas, source of this sedimentary supply, results from complex interactions between tectonics, climate, morphology, and rock erodibility. In this study, denudation rates from the present-day and ranging back to the Quaternary and the Pliocene are quantified using four independent methods allowing an investigation over different time scales: 1) compilation of present-day measured sediment fluxes, 2) determination of catchment-scale cosmogenic denudation rates through measurements of in situ-produced 10Be concentrations in sands sampled at the outlet of present-day rivers, 3) estimation of eroded volumes within catchments using a DEM to quantify long-term averaged Quaternary denudation rates, and 4) quantification of sediment volumes deposited within the marine realm of the Gulf of Lion. The results obtained by these four methods are in agreement within the range of uncertainties. The internal part of the Alps exhibits significantly higher denudation rates (∼700 mm ka-1) than those estimated in the other structural domains: 150-250 mm ka-1 in the foreland Alps, ∼100 mm ka-1 in the Pyrenees, and 55-75 mm ka-1 in the Massif Central. The Alpine domain provides at least 80% of the total eroded volume supplied towards the Gulf of Lion. A quantitative geomorphological approach shows that denudation rates are controlled at the first order by catchment morphologies (slope, relief) over different time scales, suggesting glacial conditioning to be the main driver on denudation from the Quaternary to present-day. Throughout the Pliocene-Quaternary, a doubling of denudation rates related to the mid-Pleistocene Revolution (∼0.9 Ma) is highlighted.

  16. 76 FR 18723 - Proposed Information Collection; Comment Request; Southeast Region Gulf of Mexico Red Snapper IFQ...

    Science.gov (United States)

    2011-04-05

    ... Region Gulf of Mexico Red Snapper IFQ Program AGENCY: National Oceanic and Atmospheric Administration... Act. NMFS manages the red snapper fishery in the waters of the Gulf of Mexico under the Reef Fish...

  17. Gulf of Mexico dissolved oxygen model (GoMDOM) research and quality assurance project plan

    Science.gov (United States)

    An integrated high resolution mathematical modeling framework is being developed that will link hydrodynamic, atmospheric, and water quality models for the northern Gulf of Mexico. This Research and Quality Assurance Project Plan primarily focuses on the deterministic Gulf of Me...

  18. State of oil pollution in the northern Arabian Sea after the 1991 Gulf oil spill

    Digital Repository Service at National Institute of Oceanography (India)

    Sengupta, R.; Fondekar, S.P.; Alagarsamy, R.

    Following the enormous oil spills resulting from the 1990-91 military conflict in the Gulf, fears were expressed concerning dissipation of oil from the Gulf into the Arabian Sea and Indian Ocean. To investigate contamination of the northern Arabian...

  19. Implication of coastal refineries to the ecology of the Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Anand, N.M.

    bank of the Gulf of Kachchh. An assessment of probable impact of establishment of these refineries to the rich biodiversity of the Gulf and suggestions to minimise these impacts have been made in this paper....

  20. 75 FR 1754 - Gulf of Mexico Fishery Management Council; Public Meetings

    Science.gov (United States)

    2010-01-13

    ... 33607. FOR FURTHER INFORMATION CONTACT: Dr. Stephen Bortone, Executive Director, Gulf of Mexico Fishery... committee will also consider a control rule for Gulf group King and Spanish Mackerel. Although other...

  1. Stratigraphy of two conjugate margins (Gulf of Lion and West Sardinia): modeling of vertical movements and sediment budgets

    Science.gov (United States)

    Leroux, Estelle; Gorini, Christian; Aslanian, Daniel; Rabineau, Marina; Blanpied, Christian; Rubino, Jean-Loup; Robin, Cécile; Granjeon, Didier; Taillepierre, Rachel

    2016-04-01

    The post-rift (~20-0 Ma) vertical movements of the Provence Basin (West Mediterranean) are quantified on its both conjugate (the Gulf of Lion and the West Sardinia) margins. This work is based on the stratigraphic study of sedimentary markers using a large 3D grid of seismic data, correlations with existing drillings and refraction data. The post-rift subsidence is measured by the direct use of sedimentary geometries analysed in 3D [Gorini et al., 2015; Rabineau et al., 2014] and validated by numerical stratigraphic modelling. Three domains were found: on the platform (1) and slope (2), the subsidence takes the form of a seaward tilting with different amplitudes, whereas the deep basin (3) subsides purely vertically [Leroux et al., 2015a]. These domains correspond to the deeper crustal domains respectively highlighted by wide angle seismic data. The continental crust (1) and the thinned continental crust (2) are tilted, whereas the intermediate crust, identified as lower continental exhumed crust [Moulin et al., 2015, Afhilado et al., 2015] (3) sagged. The post-break-up subsidence re-uses the initial hinge lines of the rifting phase. This striking correlation between surface geologic processes and deep earth dynamic processes emphasizes that the sedimentary record and sedimentary markers is a window into deep geodynamic processes and dynamic topography. Pliocene-Pleistocene seismic markers enabled high resolution quantification of sediment budgets over the past 6 Myr [Leroux et al., in press]. Sediment budget history is here completed on the Miocene interval. Thus, the controlling factors (climate, tectonics and eustasy) are discussed. Afilhado, A., Moulin, M., Aslanian, D., Schnürle, P., Klingelhoefer, F., Nouzé, H., Rabineau, M., Leroux, E. & Beslier, M.-O. (2015). Deep crustal structure across a young 1 passive margin from wide-angle and reflection seismic data (The SARDINIA Experiment) - II. Sardinia's margin. Bull. Soc. géol. France, 186, ILP Spec. issue, 4

  2. Holocene palaeoseismic events along northernmost segment of Dead Sea Fault Zone (Hatay-Maras) and relevant shoreline changes on eastern coast of Iskenderun Gulf, SE Turkey- N Syria

    Science.gov (United States)

    Salih Bayraktutan, Mehmet

    2010-05-01

    M.Salih Bayraktutan, BOTAS-BIL, Marine Terminal Golovasi, Ceyhan. 01499 Adana.Turkey Seismotectonic and palaeoseismic researches on the eastern coast of the Iskenderun Gulf, and northernmost segment of Dead Sea Rift zone, between Hatay-and-Maras, has revealed the several episodes of seismotectonic uplift, in late Holocene. Uplifting movements upto few meters associated with sea level changes along the NE Mediterranean coasts of Turkey (Iskenderun Gulf), Syria and N Cyprus. Submergence of DS Rift zone and the Iskenderun Gulf, resulted in uplift of Amanos Ranges. Highest rate of subsidence occurred at the area of triple-junction (Amik Basin). East Anatolian Fault Zone crossing DSR caused closing the rift at the north end. Two main sense of movements, SS and rifting, affected the Amanos range and was dissected by EAF zone branches. Coseismic vertical movements and associated sea level changes have been documented at coastal areas of eastern Meditterranean. Sea. In this article palaeoseismic and archeological data obtained from recent trenches and archeological ruins located along the Iskenderun and DSR faults presented. The correlation amoung seismic-and-depositional episodes was discussed, interms of sea level changes.

  3. Gulf team delivers on DP drillship promise

    Energy Technology Data Exchange (ETDEWEB)

    Flatern, R. von

    2001-06-01

    The technological achievements of the project by Amoco and BP to complete a deepwater subsea well in the Gulf of Mexico from a dynamically positioned (DP) vessel are described. In 2000, the dual activity drillship, Discoverer Enterprise (owned by Transocean Sedco Forex), completed the Nile well in the Viosca Knoll area and then the King Well in Mississippi Canyon Block 85. Stringent safety and environmental protection criteria imposed by Amoco and BP drove the design of the Dril-Quip subsea wellhead to ensure that the wellhead profile and connector coped with the worst case scenario. BP also specified a disconnect system that would secure the well in less than a minute. The SenTREE 7 and Commander telemetry systems developed by Schlumberger, the components of the work string and test work with the Nile well to ensure BP conditions were met and that the perforation and surge procedure proceeded successfully are explained. The time reduction achieved by using large DP drillships and future BP plans are outlined.

  4. Gulf of Mexico Oceanography Atlas available

    Science.gov (United States)

    The second full-color volume of the Atlas Oceanogáfico del Golfo de México has recently been published by the Grupo de Estudios Oceanográficos of the Instituto de Investigaciones Eléctricas of México (GEO-IIE) (see Eos, Feb. 20, 1990, for announcement of volume 1). This second of an eight-volume series describes the hydrography, baroclinic flows and transports, water masses distributions, and the kinematic properties of anticyclonic-cyclonic ring pairs (modons) of the central and western Gulf of Mexico (26°-20°40‧N, 97°40‧-93°W). The data presented and analyzed in this volume were collected during the Argos 86-1 oceanographic cruise conducted by the GEO-IIE aboard the R/V Justo Sierra during October and November 1986. Authors of the volume are Víctor M. V. Vidal, Francisco V. Vidal, and Abel Hernández. It has 16 chapters in 715 pages, including 248 full-page color plates and 35 tables.

  5. Population Structure, Abundance and Movement of Whale Sharks in the Arabian Gulf and the Gulf of Oman.

    Science.gov (United States)

    Robinson, David P; Jaidah, Mohammed Y; Bach, Steffen; Lee, Katie; Jabado, Rima W; Rohner, Christoph A; March, Abi; Caprodossi, Simone; Henderson, Aaron C; Mair, James M; Ormond, Rupert; Pierce, Simon J

    2016-01-01

    Data on the occurrence of whale sharks, Rhincodon typus, in the Arabian Gulf and Gulf of Oman were collected by dedicated boat surveys and via a public-sightings scheme during the period from 2011 to 2014. A total of 422 individual whale sharks were photo-identified from the Arabian Gulf and the northern Gulf of Oman during that period. The majority of sharks (81%, n = 341) were encountered at the Al Shaheen area of Qatar, 90 km off the coast, with the Musandam region of Oman a secondary area of interest. At Al Shaheen, there were significantly more male sharks (n = 171) than females (n = 78; X2 = 17.52, P sharks was 6.90 m ± 1.24 (median = 7 m; n = 296). Males (7.25 m ± 1.34; median = 8 m, n = 171) were larger than females (6.44 m ±1.09; median = 7 m, n = 78; Mann-Whitney U test, p sharks assessed for maturity 63% were mature (n = 81), with 50% attaining maturity by 7.29 m and 100% by 9.00 m. Two female sharks of >9 m individuals were visually assessed as pregnant. Connectivity among sharks sighted in Qatari, Omani and UAE waters was confirmed by individual spot pattern matches. A total of 13 identified sharks were re-sighted at locations other than that at which they were first sighted, including movements into and out of the Arabian Gulf through the Strait of Hormuz. Maximum likelihood techniques were used to model an estimated combined population for the Arabian Gulf and Gulf of Oman of 2837 sharks ± 1243.91 S.E. (95% C.I. 1720-6295). The Al Shaheen aggregation is thus the first site described as being dominated by mature males while the free-swimming pregnant females are the first reported from the Indian Ocean.

  6. Population Structure, Abundance and Movement of Whale Sharks in the Arabian Gulf and the Gulf of Oman.

    Science.gov (United States)

    Robinson, David P; Jaidah, Mohammed Y; Bach, Steffen; Lee, Katie; Jabado, Rima W; Rohner, Christoph A; March, Abi; Caprodossi, Simone; Henderson, Aaron C; Mair, James M; Ormond, Rupert; Pierce, Simon J

    2016-01-01

    Data on the occurrence of whale sharks, Rhincodon typus, in the Arabian Gulf and Gulf of Oman were collected by dedicated boat surveys and via a public-sightings scheme during the period from 2011 to 2014. A total of 422 individual whale sharks were photo-identified from the Arabian Gulf and the northern Gulf of Oman during that period. The majority of sharks (81%, n = 341) were encountered at the Al Shaheen area of Qatar, 90 km off the coast, with the Musandam region of Oman a secondary area of interest. At Al Shaheen, there were significantly more male sharks (n = 171) than females (n = 78; X2 = 17.52, P sharks was 6.90 m ± 1.24 (median = 7 m; n = 296). Males (7.25 m ± 1.34; median = 8 m, n = 171) were larger than females (6.44 m ±1.09; median = 7 m, n = 78; Mann-Whitney U test, p sharks assessed for maturity 63% were mature (n = 81), with 50% attaining maturity by 7.29 m and 100% by 9.00 m. Two female sharks of >9 m individuals were visually assessed as pregnant. Connectivity among sharks sighted in Qatari, Omani and UAE waters was confirmed by individual spot pattern matches. A total of 13 identified sharks were re-sighted at locations other than that at which they were first sighted, including movements into and out of the Arabian Gulf through the Strait of Hormuz. Maximum likelihood techniques were used to model an estimated combined population for the Arabian Gulf and Gulf of Oman of 2837 sharks ± 1243.91 S.E. (95% C.I. 1720-6295). The Al Shaheen aggregation is thus the first site described as being dominated by mature males while the free-swimming pregnant females are the first reported from the Indian Ocean. PMID:27362839

  7. Population Structure, Abundance and Movement of Whale Sharks in the Arabian Gulf and the Gulf of Oman

    Science.gov (United States)

    Robinson, David P.; Jaidah, Mohammed Y.; Bach, Steffen; Lee, Katie; Jabado, Rima W.; Rohner, Christoph A.; March, Abi; Caprodossi, Simone; Henderson, Aaron C.; Mair, James M.; Ormond, Rupert; Pierce, Simon J.

    2016-01-01

    Data on the occurrence of whale sharks, Rhincodon typus, in the Arabian Gulf and Gulf of Oman were collected by dedicated boat surveys and via a public-sightings scheme during the period from 2011 to 2014. A total of 422 individual whale sharks were photo-identified from the Arabian Gulf and the northern Gulf of Oman during that period. The majority of sharks (81%, n = 341) were encountered at the Al Shaheen area of Qatar, 90 km off the coast, with the Musandam region of Oman a secondary area of interest. At Al Shaheen, there were significantly more male sharks (n = 171) than females (n = 78; X2 = 17.52, P sharks was 6.90 m ± 1.24 (median = 7 m; n = 296). Males (7.25 m ± 1.34; median = 8 m, n = 171) were larger than females (6.44 m ±1.09; median = 7 m, n = 78; Mann-Whitney U test, p sharks assessed for maturity 63% were mature (n = 81), with 50% attaining maturity by 7.29 m and 100% by 9.00 m. Two female sharks of >9 m individuals were visually assessed as pregnant. Connectivity among sharks sighted in Qatari, Omani and UAE waters was confirmed by individual spot pattern matches. A total of 13 identified sharks were re-sighted at locations other than that at which they were first sighted, including movements into and out of the Arabian Gulf through the Strait of Hormuz. Maximum likelihood techniques were used to model an estimated combined population for the Arabian Gulf and Gulf of Oman of 2837 sharks ± 1243.91 S.E. (95% C.I. 1720–6295). The Al Shaheen aggregation is thus the first site described as being dominated by mature males while the free-swimming pregnant females are the first reported from the Indian Ocean. PMID:27362839

  8. Petroleum exploration potential of Tamtsag Basin

    Institute of Scientific and Technical Information of China (English)

    SUN Guo-qing; GUO Qing-xia; ZHANG Ya-jin; ZHAO Hong-wen

    2004-01-01

    The Tamtsag Basin is located in the extreme eastern portion of the Mongolia. The Basin and its counterpart in China (the Hailar Basin) are united a whole basin on the structural setting. In recent years, the Tamtsag Basin attracts more and more attention with the important exploration discovered in the 19th block by SOCO and in Hailar Basin of China. This paper discusses the exploration potential of Tamtsag Basin from the viewpoint of petroleum geology.

  9. Upwelling characteristics in the Gulf of Finland (Baltic Sea) as revealed by Ferrybox measurements in 2007-2013

    Science.gov (United States)

    Kikas, Villu; Lips, Urmas

    2016-07-01

    Ferrybox measurements have been carried out between Tallinn and Helsinki in the Gulf of Finland (Baltic Sea) on a regular basis since 1997. The system measures autonomously water temperature, salinity, chlorophyll a fluorescence and turbidity and takes water samples for further analyses at a predefined time interval. We aimed to show how the Ferrybox technology could be used to study the coastal upwelling events in the Gulf of Finland. Based on the introduced upwelling index and related criteria, 33 coastal upwelling events were identified in May-September 2007-2013. The number of events, as well as the frequency of their occurrence and intensity expressed as a sum of daily average temperature deviations in the 20 km wide coastal area, were almost equal near the northern and southern coasts. Nevertheless, the wind impulse, which was needed to generate upwelling events of similar intensity, differed between the northern and southern coastal areas. It is suggested that the general thermohaline structure adapted to the prevailing forcing and the estuarine character of the basin weaken the upwelling created by the westerly to southwesterly (up-estuary) winds and strengthen the upwelling created by the easterly to northeasterly (down-estuary) winds. Two types of upwelling events were identified - one characterized by a strong temperature front and the other revealing gradual decrease in temperature from the open sea to the coastal area, with maximum temperature deviation close to the shore.

  10. Detachment Faulting and Hanging-wall Segmentation in the Gulf Extensional Province, Baja California

    Science.gov (United States)

    Seiler, C.; Fletcher, J. M.; Quigley, M. C.; Gleadow, A. J.; Kohn, B. P.

    2007-12-01

    The opening of the Gulf of California, caused by the re-localization of the Pacific -- North America plate boundary, is a premier example of an incipient passive margin. The San Felipe area in northern Baja California comprises a typical basin and range-style topography, produced by Neogene extension affecting the Gulf Extensional Province (GEP). The > 100 km long Sierra San Pedro Mártir (SSPM) escarpment is defined by an east-down normal fault system, separating the unextended western part of the peninsula from the GEP. The hanging-wall of the SSPM fault is characterized by several fault-bound blocks that have been rotated around both vertical and horizontal axes. The Las Cuevitas and the Santa Rosa detachments are two major fault systems in the Sierra San Felipe that are responsible for segmentation of the hanging-wall of the SSPM fault. The curvilinear, NE to NNW striking Las Cuevitas Detachment extends for more than 43 km and brings Neogene volcanics and sediments in contact with the Mesozoic basement of the footwall. The detachment dips at 15-50° and accommodates more than 4-6 km of east-down displacement. Faulting appears to preferentially occur at the contact of Mesozoic metamorphics to granitoid intrusives with transfer faults translating deformation between the faulted contacts. Fission track and (U-Th)/He thermochronology constrain the initiation of deformation on the Las Cuevitas detachment to the latest Miocene. The > 45 km long and equally curvilinear Santa Rosa Detachment system consists of a low-angle normal fault system (15-35° dip) with transfer zones facilitating the transfer of strain between individual segments of the detachment fault. The slip direction varies between top-to-the-east and top-to-the-south, a possible explanation for the change in strike from NW to NE to NW. The roughly 4-5 km offset of Neogene volcanic and sedimentary deposits has created the necessary space for syntectonic deposition in the Santa Rosa Basin. The onset of

  11. Archeterokrohnia docrickettsae (Chaetognatha: Phragmophora: Heterokrohniidae), a new species of deep-sea arrow worm from the Gulf of California.

    Science.gov (United States)

    Thuesen, Erik V; Haddock, Steven H D

    2013-01-01

    A new species of deep-sea chaetognath, Archeterokrohnia docrickettsae n. sp. is described from a single specimen captured by the ROV Doc Ricketts ~2 m above the sea floor at 3245 m depth in the Pescadero Basin of the Gulf of California, Mexico. This is the first record of a living specimen of Archeterokrohnia and the second known occurrence of Archeterokrohnia in the Pacific Ocean. In life, the head and trunk sections were orange, while the tail section was translucent, a unique colour pattern not before seen in chaetognaths. Observations of its swimming behaviour in situ are given. Comparisons are made with the three other species of Archeterokrohnia. At 28.5 mm in length, this is the largest known species of the genus. An artificial key to the four species of Archeterokrohnia is presented. PMID:26176108

  12. Is Gulf War Syndrome actually chronic Lyme disease?

    Science.gov (United States)

    Owen, David C

    2005-01-01

    Symptoms of Gulf War Syndrome and chronic Lyme disease are very similar. Lyme disease is a condition which can be difficult to diagnose since one of the main features of the condition, the erythema migrans rash, may be absent or overlooked and serological testing for Lyme disease may be falsely negative. Symptoms of Lyme disease may not became apparent until years after exposure to the causative organism. Military personnel during training in the field are at risk of tick bites and it may be that those who developed Gulf War Syndrome entered the conflict with latent Lyme disease. There has been no systematic examination of Gulf War Syndrome sufferers for chronic Lyme disease and it is hypothesized that chronic Lyme disease has been overlooked as a cause of Gulf War Syndrome. To address this it is suggested that sufferers of Gulf War Syndrome or similar illnesses should be examined by physicians who have experience diagnosing and treating large numbers of patients with Lyme disease.

  13. Gulf Stream density structure and transport during the past millennium.

    Science.gov (United States)

    Lund, David C; Lynch-Stieglitz, Jean; Curry, William B

    2006-11-30

    The Gulf Stream transports approximately 31 Sv (1 Sv = 10(6) m(3) s(-1)) of water and 1.3 x 10(15) W of heat into the North Atlantic ocean. The possibility of abrupt changes in Gulf Stream heat transport is one of the key uncertainties in predictions of climate change for the coming centuries. Given the limited length of the instrumental record, our knowledge of Gulf Stream behaviour on long timescales must rely heavily on information from geologic archives. Here we use foraminifera from a suite of high-resolution sediment cores in the Florida Straits to show that the cross-current density gradient and vertical current shear of the Gulf Stream were systematically lower during the Little Ice Age (ad approximately 1200 to 1850). We also estimate that Little Ice Age volume transport was ten per cent weaker than today's. The timing of reduced flow is consistent with temperature minima in several palaeoclimate records, implying that diminished oceanic heat transport may have contributed to Little Ice Age cooling in the North Atlantic. The interval of low flow also coincides with anomalously high Gulf Stream surface salinity, suggesting a tight linkage between the Atlantic Ocean circulation and hydrologic cycle during the past millennium.

  14. Canterbury Basin Sea Level

    OpenAIRE

    Fulthorpe, C. S.; Institute for Geophysics John A. and Katherine G. Jackson School of Geosciences The University of Texas at Austin J.J. Pickle Research Campus, Building 196 (ROC) 10100 Burnet Road (R2200) Austin TX 78758-4445 USA; Hoyanagi, K.; Department of Geology Faculty of Science Shinshu University 3-1-1 Asahi, Matsumoto 390-8621 Japan; Blum, P.; United States Implementing Organization Integrated Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station TX 77845 USA; Guèrin, G.; Borehole Research Group Lamont-Doherty Earth Observatory of Columbia University PO Box 1000, 61 Route 9W Palisades NY 10964 USA; Slagle, A. L.; Borehole Research Group Lamont-Doherty Earth Observatory of Columbia University PO Box 1000, 61 Route 9W Palisades NY 10964 USA; Blair, S. A.; Department of Geological Sciences Florida State University 006 Carraway Building Tallahassee FL 32306 USA; Browne, G. H.; Hydrocarbon Section GNS Science PO Box 30368 Lower Hutt New Zealand; Carter, R. M.; Marine Geophysical Laboratory James Cook University of North Queensland Townsville QLD 4811 Australia; Ciobanu, M.; Laboratoire de Microbiologie des Environnements Extrêmes CNRS UMR-6197 Institut Universitaire Européen de la Mer Technopole Brest-Iroise Plouzane 29280 France; Claypool, G. E.; Organic Geochemist 8910 West 2nd Avenue Lakewood CO 80226 USA; Crundwell, M. P.; New Zealand Observer/Paleontologist (foraminifers) Paleontology and Environmental Change Section GNS Science PO Box 30368 Lower Hutt New Zealand; Dinarès-Turell, J.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Ding, X.; School of Marine Sciences China University of Geosciences (Beijing) 29 XueYuan Road, Haidian District Beijing P.R. China; George, S. C.; Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia; Hepp, D. A.; MARUM – Center for Marine Environmental Sciences and Department of Geosciences University of Bremen Leobener Strasse MARUM Building, Room 2230 28359 Bremen Germany

    2010-01-01

    Integrated Ocean Drilling Program (IODP) Expedition 317 was devoted to understanding the relative importance of global sea level (eustasy) versus local tectonic and sedimentary processes in controlling continental margin sedimentary cycles. The expedition recovered sediments from the Eocene to recent period, with a particular focus on the sequence stratigraphy of the late Miocene to recent, when global sea level change was dominated by glacioeustasy. Drilling in the Canterbury Basin,...

  15. The consequences and hazards of depleted uranium weapons used by US army since gulf war

    International Nuclear Information System (INIS)

    Military equipment and development of depleted uranium weapon in USA, the depleted uranium weapon used in gulf war by USA army, personnel irradiation in the gulf war, and the protection in the gulf war are introduced. The radioactivity, radioactive characteristics, chemical toxicity and hazard of the depleted uranium are also introduced

  16. Observing environmental change in of the Gulf of Maine: ICUC smartphone app

    Science.gov (United States)

    Want to help collect data on environmental change in the Gulf of Maine with your smartphone? The Gulf of Maine Council’s EcoSystem Indicator Partnership (ESIP) is growing the community of citizen scientists in the Gulf of Maine region through its new smartphone app: ICUC (...

  17. Africa and Arab Gulf states : Divergent Development Paths and Prospects for Convergence

    OpenAIRE

    Fofack, Hippolyte

    2009-01-01

    In spite of the similarities between Sub-Saharan Africa and the Arab Gulf region (Gulf Cooperation Council states), development policies implemented in these two regions of the world have produced markedly different and even divergent outcomes. While Gulf Cooperation Council states have drawn on hydrocarbon revenues to dramatically transform their economic landscape, Sub-Saharan African co...

  18. The gulf implantable cardioverter-defibrillator registry: Rationale, methodology, and implementation

    Directory of Open Access Journals (Sweden)

    Alawi A Alsheikh-Ali

    2015-01-01

    Conclusions: Gulf ICD is the first prospective, observational, multi-center, and multinational study of the characteristics and, the outcomes of patients receiving ICDs in the Arab Gulf region. The study will provide valuable insights into the utilization of and outcomes related to ICD therapy in the Gulf region.

  19. 78 FR 77105 - Gulf of Mexico Fishery Management Council (Council); Public Meetings

    Science.gov (United States)

    2013-12-20

    ... National Oceanic and Atmospheric Administration RIN 0648-XD037 Gulf of Mexico Fishery Management Council... Atmospheric Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Gulf of Mexico..., 2014 at nine locations throughout the Gulf of Mexico. The Council will also host a webinar...

  20. 78 FR 63966 - Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-10-25

    ... National Oceanic and Atmospheric Administration RIN 0648-XC930 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice; public meeting. SUMMARY: The Gulf of Mexico Fishery Management... meeting will be held at the Gulf of Mexico Fishery Management Council, 2203 North Lois Avenue, Suite...

  1. 78 FR 33070 - Gulf of Mexico Fishery Management Council; Public Meetings

    Science.gov (United States)

    2013-06-03

    ... National Oceanic and Atmospheric Administration RIN 0648-XC709 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Gulf of Mexico Fishery... address: Gulf of Mexico Fishery Management Council, 2203 North Lois Avenue, Suite 1100, Tampa, FL...

  2. 75 FR 69921 - Gulf of Mexico Fishery Management Council; Public Meetings

    Science.gov (United States)

    2010-11-16

    ... National Oceanic and Atmospheric Administration RIN 0648-XA027 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Gulf of Mexico Fishery... Blvd., Webster, TX 77598; telephone: (281) 332-7952. Council Address: Gulf of Mexico Fishery...

  3. 78 FR 61842 - Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-10-04

    ... National Oceanic and Atmospheric Administration RIN 0648-XC912 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Meeting of the Gulf of Mexico Fishery Management Council. SUMMARY: The Gulf of Mexico Fishery Management Council (Council) will hold meetings of the: Mackerel,...

  4. 78 FR 59656 - Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-09-27

    ... National Oceanic and Atmospheric Administration RIN 0648-XC892 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of a public meeting. SUMMARY: The Gulf of Mexico Fishery...; telephone: (956) 761-6511. Council address: Gulf of Mexico Fishery Management Council, 2203 North...

  5. 77 FR 41376 - Gulf of Mexico Fishery Management Council; Public Meetings

    Science.gov (United States)

    2012-07-13

    ... National Oceanic and Atmospheric Administration Gulf of Mexico Fishery Management Council; Public Meetings...), Commerce. ACTION: Council to convene public meetings. SUMMARY: The Gulf of Mexico Fishery Management... Gulf of Mexico Fishery Management Council's Web site at www.gulfcouncil.org for instructions....

  6. 78 FR 4130 - Gulf of Mexico Fishery Management Council; Public Meetings

    Science.gov (United States)

    2013-01-18

    ... Offshore Marine Aquaculture in the Gulf of Mexico. 9:30 a.m.-9:45 a.m.--The Council will vote on Exempted... National Oceanic and Atmospheric Administration RIN 0648-XC449 Gulf of Mexico Fishery Management Council... Administration (NOAA), Commerce. ACTION: Notice of public meetings. SUMMARY: The Gulf of Mexico...

  7. Syn-rift volcanism and seafloor-spreading in the northern Gulf of Mexico: results from the GUMBO marine seismic refraction project

    Science.gov (United States)

    Eddy, D. R.; Van Avendonk, H. J.; Christeson, G. L.; Norton, I. O.; Karner, G. D.; Kneller, E. A.; Johnson, C. A.; Snedden, J.

    2013-12-01

    Continental rifting and seafloor-spreading between North America and the Yucatán Block during the Jurassic to early Cretaceous formed the small ocean basin known today as the Gulf of Mexico. The lack of deeply-penetrating geophysical data in the Gulf of Mexico limited early reconstructions of the timing and location of the rift-to-drift transition, particularly with respect to the influence of magmatism on the breakup of continental crust and the onset of seafloor-spreading. To better understand the deep structure of this economically important basin, we acquired four marine seismic refraction profiles in the northern Gulf of Mexico from the shelf to deep water as part of the 2010 Gulf of Mexico Basin Opening project (GUMBO). We use travel times from long-offset reflections and refractions to image compressional seismic velocities in the sediments, crystalline crust, and upper mantle using an iterative tomographic inversion. GUMBO Line 3 extends from offshore Alabama through the De Soto Canyon towards the central Gulf of Mexico. We interpret velocities >5.0 km/s in the sediment layer landward of the Florida Escarpment as a Lower Cretaceous carbonate platform. Crystalline crust with velocities between 5.5-7.5 km/s thins significantly from 23 km to 7 km across a narrow necking zone. A deep, localized region of anomalously high seismic velocities (>7.5 km/s) at the base of crystalline crust exceeds those of continental lower crust in the eastern US. We interpret this section of GUMBO 3 to represent mafic under-plating and/or infiltration of asthenospheric melts, common at volcanic rifted margins. The seaward end of GUMBO 3 has seismic velocities consistent with mafic ocean crust produced by normal seafloor-spreading (6.0-7.5 km/s); this observation is supported by a consistent crustal thickness of ~7 km and minimal lateral heterogeneities in velocity structure. GUMBO Line 2 extends from offshore Louisiana southward across the Sigsbee Escarpment. We find a massive

  8. A Novel Approach to River Basin Management that Utilizes a Multi-Day Forum to Educate Stakeholders

    Science.gov (United States)

    Langston, M. A.

    2015-12-01

    Large scale river basin management has long been a challenging task. Stakeholder involvement has often been posited as a means to provide a broad base of input and support for management decisions. This has been successful in some situations and not in others. The Desert Landscape Conservation Cooperative (LCC) has proposed a novel approach to large scale watershed management for conservation purposes by stakeholders. This approach involves conducting a multi-day stakeholder forum to gather interested parties, provide them science-based information about the watershed, and solicit their input regarding the research and management needs within the basin. Included within this forum is a Water Tournament patterned after those being developed by the U.S. Army Corps of Engineers' Institute for Water Resources. These tournaments bring stakeholders (such as the various water users, agencies, conservation organizations, and others) in small teams that develop watershed management scenarios (within appropriate constraints) that are then judged based on their merit for addressing the various issues within the basin. These tournaments serve to educate participants and to sensitize them to the perspectives of other participants. Another goal of the forum is to recruit a representative group of stakeholders who will provide guidance for further research to meet the basins management needs. The South Central Climate Science Center (SC CSC) has partnered with the Desert, Southern Rockies, Gulf Coast Prairie, Great Plains, and Gulf Coastal Plains and Ozarks LCCs to implement this approach in the Rio Grande and the Red River Basins. The LCCs are well positioned to convene stakeholders from across political boundaries and throughout these basins. The SC CSC's roles will be providing leadership, funding climate science for the effort, and evaluating the effectiveness of the forum-centered approach.

  9. Chemical quality of surface waters in the Brazos River basin in Texas

    Science.gov (United States)

    Irelan, Burdge; Mendieta, H.B.

    1964-01-01

    The Brazos River basin, which makes up 15 percent of the land area of Texas, extends from the High Plains, where altitudes reach 4,200 feet and the average precipitation ranges from 15 to 20 inches a year, to the Gulf of Mexico where the annual rainfall is 45-^50 inches. Large reservoirs have been built in the Brazos River basin, but the use of the stored water has been limited because the salinity often makes the water undesirable for municipal and industrial use. However, the water is generally satisfactory for irrigation. Records for the Brazos River show that the salinity of the water was a problem even as early as 1906 and that the water more often than not failed to meet today's chemical-quality standards for a municipal supply.

  10. Late differentiation of proximal and distal margins in the Gulf of Aden

    Science.gov (United States)

    Bache, F.; Leroy, S.; D'Acremont, E.; Autin, J.; Watremez, L.; Rouzo, S.

    2009-04-01

    Non-volcanic passive margins are usually described in three different domains (Boillot et al., 1988), namely (1) the continental domain, where the basement is structured in a series of basins and basement rises, (2) the true oceanic domain, where the bathymetry is relatively smooth, and (3) in between them, a transitional domain referred to as the oceanic-continental transition (OCT), where the basement is partly composed of exhumed mantle. The Gulf of Aden is a young and narrow oceanic basin formed in Oligo-Miocene time between the rifted margins of the Arabian and Somalian plates. The distal margin and particularly the OCT domain were previously studied considering a large set of data (Leroy et al., 2004; d'Acremont et al., 2005; d'Acremont et al., 2006; Autin, 2008). This study focalises on the sedimentary cover identified on seismic reflexion profiles acquired during Encens-Sheba (2000) and Encens (2006) cruises. Sedimentary stratal pattern and seismic facies succession suggest that the differentiation between the proximal and the distal margins occurred very late in the formation of the margin, after the deposition of ~2 km of "syn-OCT" sediments which filled the distal margin grabens. A high position of the proximal and distal margins during rifting and "syn-OCT" sediments deposition could be proposed. The major implication of this evolution should be a shallow nature of "syn-OCT" deposits. The lack of boreholes doesn't permit to affirm this last point. Comparable observations have been described on other passive margins (Moulin, 2003; Moulin et al., 2005; Labails, 2007; Aslanian et al., 2008; Bache, 2008). For some authors, it shows the persistence of a deep thermal anomaly during the early history of the margin (Steckler et al., 1988; Dupré et al., 2007). These observations could be a common characteristic of passive margins evolution and are of major interest for petroleum exploration. Aslanian, D., M. Moulin, O. J.L., P. Unternehr, F. Bache, I. Contrucci

  11. Sea surface temperature and Ekman transport in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    E. H.

    2002-12-01

    Full Text Available   The wind drift motion of the water which is produced by the stress of the wind exerted upon the surface of the ocean is described by Ekmans theory (1905. Using the mean monthly values for the wind stress and SST, seasonal Ekman transport for the Persian Gulf was computed and contoured. The geostrophic winds have combined with the SST to estimate the effect of cooling due to Ekman transport of colder northern waters and inflow from the Oman Sea. The monthly SST mainly obtained from the 10 10 grided data of Levitus atlas and Hormuz Cruis Experiment for 1997.   Analyses show a NW to SE Ekman transport due to wind stress and significant interannual variability of SST on sea surface in the Persian Gulf. The seasonal variation of SST shows a continental pattern due to severe interaction between the land and sea. But these variations somehow moderates because of Ekman transport in Persian Gulf.

  12. Reproductive health and pregnancy outcomes among French gulf war veterans

    Directory of Open Access Journals (Sweden)

    Bégassat Marion

    2008-04-01

    Full Text Available Abstract Background Since 1993, many studies on the health of Persian Gulf War veterans (PGWVs have been undertaken. Some authors have concluded that an association exists between Gulf War service and reported infertility or miscarriage, but that effects on PGWV's children were limited. The present study's objective was to describe the reproductive outcome and health of offspring of French Gulf War veterans. Methods The French Study on the Persian Gulf War (PGW and its Health Consequences is an exhaustive cross-sectional study on all French PGWVs conducted from 2002 to 2004. Data were collected by postal self-administered questionnaire. A case-control study nested in this cohort was conducted to evaluate the link between PGW-related exposures and fathering a child with a birth defect. Results In the present study, 9% of the 5,666 Gulf veterans who participated reported fertility disorders, and 12% of male veterans reported at least one miscarriage among their partners after the PGW. Overall, 4.2% of fathers reported at least one child with a birth defect conceived after the mission. No PGW-related exposure was associated with any birth defect in children fathered after the PGW mission. Concerning the reported health of children born after the PGW, 1.0% of children presented a pre-term delivery and 2.7% a birth defect. The main birth defects reported were musculoskeletal malformations (0.5% and urinary system malformations (0.3%. Birth defect incidence in PGWV children conceived after the mission was similar to birth defect incidence described by the Paris Registry of Congenital Malformations, except for Down syndrome (PGWV children incidence was lower than Registry incidence. Conclusion This study did not highlight a high frequency of fertility disorders or miscarriage among French PGW veterans. We found no evidence for a link between paternal exposure during the Gulf War and increased risk of birth defects among French PGWV children.

  13. Multi-sensor in situ observations to resolve the sub-mesoscale features in the stratified Gulf of Finland, Baltic Sea

    Science.gov (United States)

    Lips, Urmas; Kikas, Villu; Liblik, Taavi; Lips, Inga

    2016-05-01

    High-resolution numerical modeling, remote sensing, and in situ data have revealed significant role of sub-mesoscale features in shaping the distribution pattern of tracers in the ocean's upper layer. However, in situ measurements are difficult to conduct with the required resolution and coverage in time and space to resolve the sub-mesoscale, especially in such relatively shallow basins as the Gulf of Finland, where the typical baroclinic Rossby radius is 2-5 km. To map the multi-scale spatiotemporal variability in the gulf, we initiated continuous measurements with autonomous devices, including a moored profiler and Ferrybox system, which were complemented by dedicated research-vessel-based surveys. The analysis of collected high-resolution data in the summers of 2009-2012 revealed pronounced variability at the sub-mesoscale in the presence of mesoscale upwelling/downwelling, fronts, and eddies. The horizontal wavenumber spectra of temperature variance in the surface layer had slopes close to -2 between the lateral scales from 10 to 0.5 km. Similar tendency towards the -2 slopes of horizontal wavenumber spectra of temperature variance was found in the seasonal thermocline between the lateral scales from 10 to 1 km. It suggests that the ageostrophic sub-mesoscale processes could contribute considerably to the energy cascade in such a stratified sea basin. We showed that the intrusions of water with different salinity, which indicate the occurrence of a layered flow structure, could appear in the process of upwelling/downwelling development and relaxation in response to variable wind forcing. We suggest that the sub-mesoscale processes play a major role in feeding surface blooms in the conditions of coupled coastal upwelling and downwelling events in the Gulf of Finland.

  14. Shrimp Farms and Mangroves, Gulf of Fonseca

    Science.gov (United States)

    2002-01-01

    For decades, astronauts on space missions have documented land use changes around the world. In this pair of images, astronauts track the development of shrimp farming along the Honduran coastline of the Gulf of Fonseca between 1989 and 2001. Mariculture, primarily shrimp farming, has become a leading agricultural effort in Honduras. The regional transformation of large tracts of coastal swamps into shrimp farms blossomed throughout the 1990s. The top image was taken with color infrared film in 1989. Dense vegetation, like the coastal mangrove swamps and the forested slopes of Volcan Cosiguina show up as dark red. The bottom image, taken with color visible film by the crew of the most recent Space Shuttle mission in December 2001 shows that hundreds of square kilometers of coastal swamp, primarily in Honduras, have been converted to shrimp ponds. These appear as the light-colored, rectilinear land use pattern. The Honduras shrimp farms were hit hard by flooding after Hurricane Mitch in 1998, and a devastating virus in 1999-2000. It is not known how many of the ponds in this view are still functional. A vigorous debate continues about the sustainability of the shrimp farms and the impacts to the environment and coastal ecosystem due to mangrove clearing and mariculture waste production. Apart from the shrimp farms, the other prominent feature on these images is the impressive volcano Cosiguina, which erupted explosively in 1859 (the largest recorded eruption in the Western Hemisphere). Photograph STS-108-717-85 was taken in the December 2001 by the crew of Space Shuttle mission 108 using a Hasselblad camera with 250-mm lens. Photograph STS030-93-15 was taken in May 1989 using a Hasselblad camera and color infrared film. Both images are provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  15. Crustal Deformation in the Southwestern Gulf of Mexico: Underthrusting of the Gulf of Mexico beneath Tehuantepec

    Science.gov (United States)

    Suarez, Gerardo; Aguilar, Sergio

    2016-04-01

    An array of 45 broad band sensors were installed along the Isthmus of Tehuantepec in southeastern. This experiment, called VEOX, was implemented on August 2007 to March 2009. Data were registered continuously during the whole period. In order to search in the seismic records of the data obtained for crustal events in the Isthmus of Tehuantepec, To this purpose, an STA/LTA algorithm was designed to detect earthquakes with S-P times indicating they occurred close the seismic stations, at crustal or upper mantle depths. During the 18 months that the experiment lasted, about 40 crustal earthquakes were recorded in more than three stations, allowing us to determine a hypo central location. All earthquakes occurring at depths greater than 120 km, within the subjected slab, were discarded. The majority of this crustal or upper mantle activity occurred in the northern part of the Isthmus, along the coast of the Gulf of Mexico or just inland from it. No velocity model exists in the area. Therefore, we tested three different velocity models, including one obtained in an adjacent region and based on seismic refraction data. One of these three models rendered the more stable solutions and smaller errors in the hypocentral locations and was used as the local seismic velocity model. In order to improve the quality of the locations, we experimented using a double difference hypocentral algorithm (HYPODD). There was no noticeable improvement in the quality of the hypocenters using this technique. The best located events suggest a southwestern-dipping zone of seismic seismicity, deepening from the Gulf of Mexico towards the interior of the Isthmus of Tehuantepec. The focal mechanisms of the earthquakes indicate the maximum axis of compresion (P axis) is oriented nearly horizontally and in a southwest-northeast direction. These mechanisms are similar to those observed for earthquakes previously studied in the region on the basis of teleseismic data, such as the Mw 6.9, 29 August

  16. Tides in the Gulf of Khambhat, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, R.K.; Shetye, S.R.

    of Khambhat do reproduce the observed pattern of variability of tides in the gulf. In Section 3, the response of the channel as a function of spatial position to tidal forcing at different periods is examined. The pattern of response, as a function... influenced by channel geometry and by friction. The response of the model Gulf of Khambhat is then com- pared with response of model channels representative of other better-known embayments. Section 4 summarises the results of the study. 2. A model for tides...

  17. Sea level differences across the Gulf Stream and Kuroshio extension

    Science.gov (United States)

    Zlotnicki, Victor

    1991-01-01

    The sea level differences between the Sargasso Sea and the slope waters across the Gulf Stream region, averaged between 73 and 61 deg W, and the comparable areas across the Kuroshio extension region, averaged between 143 and 156 deg E, were estimated using the Geosat altimeter data obtained between November 1986 and December 1988. The sea-level differences between the two regions showed a strong correlation between the northwest Atlantic and Pacific, dominated by annual cycles that peak in late-September to mid-October, with about 9 cm (the Gulf Stream region) and about 6.9 cm (Kuroshio region) amplitudes.

  18. Remote Sensing of Suspended Sediment Over Gulf of Martaban

    OpenAIRE

    Matamin Abd Rahman; Ahmad Fadhli; Mamat Mustafa; Abdullah Khiruddin; Harun Shahariah

    2015-01-01

    Gulf of Martaban is located at the north of Andaman, and is one of the world most turbid areas. The presence of suspended sediment concentration (SSC) in the water body could reduce the underwater transmittance. This study has been conducted to investigate the variation of SSC over the Gulf of Martaban. Remote sensing reflectance (Rrs) of 667 nm is used as a proxy to represent the sediment SSC variation over the study area. The data for the period of July 2002 to March 2014 acquired from MODI...

  19. Viscosity correlations for Gulf of Mexico crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Petrosky, G.E. Jr.; Farshad, F.F. [Univ. of Southwestern Louisiana, Lafayette, LA (United States)

    1995-12-31

    In 1984, Sutton and Farshad evaluated the accuracy of several published viscosity correlations for application in the Gulf of Mexico. A total of 31 different crude oil systems from the Louisiana and Texas gulf coast were used in their analysis. The errors encountered were rather high for dead and saturated oil viscosity. New empirical viscosity correlations for estimating dead oil, saturated oil and undersaturated oil viscosities have been developed as a function of commonly available field data. Results show that these viscosities can be predicted with average absolute errors ranging from 2.91% for undersaturated oil viscosity to 14.47% for saturated oil viscosity.

  20. Oil and gas, strategic regional cooperation between Persian Gulf countries

    Energy Technology Data Exchange (ETDEWEB)

    Zalloi, Mir Mahdi

    2010-09-15

    Almost two-thirds of proven oil and a third of world natural gas resources are in the Persian Gulf countries. Unfortunately strategic region of Persian Gulf in the past three decades faced with many security challenges due to wars and political conflicts. For security in this region, there are several methods such as military treaties between regional countries or Military presence of foreign countries, but historical evidence has shown, none of them could not guarantee the stable security in this region. The regional cooperation between countries can be replaced to mentioned methods. IPI Gas pipeline is an objective sample for this regional cooperation.

  1. Strontium-90 in the western Gulf of Mexico

    International Nuclear Information System (INIS)

    The results of measurements of 90Sr in water, coral, hermit crabs and molluscs from the western Gulf of Mexico and in fresh water molluscs from Canyon Lake, Texas are reported. Preparation of samples for measurement in the anticoincidence mode in a lead shielded flow proportional counter is described. The measured value of 0.095 +- 0.003 pCi/litre for Gulf water is in accord with literature values. Concentration factors for 90Sr are apparently 1 for coral. The activity incorporated into shells normalized to calcium content, decreases from Galveston to Campeche Bay. (U.K.)

  2. Education in the Gulf Monarchies: Retrospect and Prospect

    Science.gov (United States)

    Bahgat, Gawdat

    1999-03-01

    For the last several decades there has been tremendous expansion in the educational facilities in all the six Gulf monarchies (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates). The quality of education, however, does not correspond to the needs of Gulf societies. This study examines three of the apparent deficiencies in the educational system in the region: the mismatch between traditional and modern learning, the imbalance between indigenous and expatriate labor forces, and the gap between men and women. The paper concludes that a fundamental change in the quality of education needs to be made in order to overcome these imbalances.

  3. Multiple oscillatory modes of the Argentine Basin. Part II. The spectral origin of the basin modes

    NARCIS (Netherlands)

    Weijer, W.; Vevier, F.; Gille, S.T.; Dijkstra, H.A.

    2007-01-01

    In this paper the spectrum of barotropic basin modes of the Argentine Basin is shown to be connected to the classical Rossby basin modes of a flat-bottom (constant depth), rectangular basin. First, the spectrum of basin modes is calculated for the Argentine Basin, by performing a normal-mode analysi

  4. Intracontinental basins and strong earthquakes

    Institute of Scientific and Technical Information of China (English)

    邓起东; 高孟潭; 赵新平; 吴建春

    2004-01-01

    The September 17, 1303 Hongtong M=8 earthquake occurred in Linfen basin of Shanxi down-faulted basin zone. It is the first recorded M=8 earthquake since the Chinese historical seismic records had started and is a great earthquake occurring in the active intracontinental basin. We had held a Meeting of the 700th Anniversary of the 1303 Hongtong M=8 Earthquake in Shanxi and a Symposium on Intracontinental Basins and Strong Earthquakes in Taiyuan City of Shanxi Province on September 17~18, 2003. The articles presented on the symposium discussed the relationships between active intracontinental basins of different properties, developed in different regions, including tensional graben and semi-graben basins in tensile tectonic regions, compression-depression basins and foreland basins in compressive tectonic regions and pull-apart basins in strike-slip tectonic zones, and strong earthquakes in China. In this article we make a brief summary of some problems. The articles published in this special issue are a part of the articles presented on the symposium.

  5. Plio-Quaternary kinematic development and paleostress pattern of the Edremit Basin, western Turkey

    Science.gov (United States)

    Gürer, Ömer Feyzi; Sangu, Ercan; Özburan, Muzaffer; Gürbüz, Alper; Gürer, Aysan; Sinir, Hasan

    2016-06-01

    The Edremit Basin and Kazdağ High are the most prominent morphological features of the Biga Peninsula in northwest Anatolia. There is still no consensus on the formation of Edremit Basin and debates are on whether the basin evolved through a normal, a right-lateral or a left-lateral strike-slip faulting. In this study, the geometric, structural and kinematic characteristics of the Edremit Basin are investigated to make an analytical approach to this problem. The structural and kinematic features of the faults in the region are described according to field observations. These fault-slip data derived from the fault planes were analyzed to determine the paleostress pattern of faulting in the region. According to the performed analysis, the southern end of the Biga Peninsula is under the influence of the ENE-WSW-trending faults of the region, such as the Yenice-Gönen, the Edremit, the Pazarköy and the Havran-Balıkesir Fault Zones. The right step-over geometry and related extension caused to the development of the Edremit Basin as a transtensional pull-apart basin between the Havran-Balıkesir Fault Zone and the Edremit Fault Zone. Field observations showed that the Plio-Quaternary faults at the Edremit Gulf and adjacent areas are prominently right-lateral strike-slip faults. Our paleostress analyses suggest a dominant NE-SW extension in the study area, as well as NW-SE direction. This pattern indicates the major effects of the North Anatolian Fault System and the component of Aegean Extensional System in the region. However, our kinematic analysis represents the dominant signature of the North Anatolian Fault System in basin bounding faults. The field observations and kinematic findings of this study are also consistent with the regional GPS, paleomagnetic and seismological data. This study concludes that the North Anatolian Fault System is the prominent structure in the current morphotectonic framework of the Edremit Gulf and adjacent areas.

  6. Contributions to the sea level seasonal cycle within the Gulf of Cadiz (Southwestern Iberian Peninsula)

    Science.gov (United States)

    Laiz, Irene; Tejedor, Begoña; Gómez-Enri, Jesús; Aboitiz, Alazne; Villares, Pilar

    2016-07-01

    The spatial distribution of the sea level seasonal cycle within the Gulf of Cadiz (GoC) has been analysed using monthly maps of sea level anomalies from gridded multi-mission altimeter data, along with monthly means of sea level heights from three tide gauge stations. Moreover, the contribution to the sea level seasonal cycle of atmospheric pressure and wind and the steric effect were evaluated using maps of sea level residuals from the VANI2-ERA hindcast, and a combination of satellite Sea Surface Temperature maps with a very high resolution Temperature and Salinity climatology for the region. The atmospheric contribution accounted for 55-58% of the sea level variance offshore, with this percentage diminishing toward the coast, where the effect of wind stress might be underestimated, especially over regions of complex bathymetry. The steric contribution was addressed by considering local, open ocean, basin-wide and continental shelf steric effects. Results obtained highlighted the oceanographic complexity of the GoC at regional scales. In this sense, the open ocean steric contribution explained the largest percentage of atmospheric-corrected sea level variance at the offshore part of the basin (50-67%) and over the eastern shelf (42-48%), suggesting that the sea level seasonal cycle within the eastern shelf is connected to the large scale circulation system. West of Cape Santa Maria, both over the continental shelf and offshore, the best results were obtained with the local steric contribution, suggesting a decoupling of deep and shallow water sea level variations at the seasonal scale in that region.

  7. Wisconsinan-Holocene seismic stratigraphy of the Keathley Canyon Area and vicinity, northwestern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gwang Hoon; Bryant, W.R.; Watkins, J.S. (Texas A and M Univ., College Station (United States))

    1991-03-01

    The lower continental slope of the northwestern Gulf of Mexico is characterized by a hummocky topography with shallow salt masses interspersed by numerous salt-withdrawal basins containing thick Plio-Pleistocene and older sediments. Analysis of over 7500 km of multichannel seismic reflection data from the Keathley Canyon Area and vicinity defined the Wisconsinan-Holocene sequence and its seismic facies. In interbasinal areas and in the southern part of the study area where salt is shallow, the Wisconsinan-Holocene sequence consists mainly of low-amplitude (LA) facies underlain by strong basal-reflection (SBR) facies. The LA facies occasionally show subtle onlaps against SBR facies and grade upward into a draping pattern. Onlapping LA facies are interpreted to be a lowstand systems tract deposited by widespread low-energy turbidity currents. Draping LA facies at the top may consist of hemipelagic or pelagic sediments. The SBR facies are interpreted to consist of condensed sections formed during sea-level rises and highstands. Within basins, moderate-to-high amplitude-continuous (MHC) and hummocky-to-chaotic (HC) facies occur below LA facies. The MHC facies show a pattern of flat-lying or gently dipping reflections that onlap SBR facies. Onlapping MHC facies often grade upward into a conformable pattern and are obscured by transition into LA facies. The MHC facies are interpreted as alternating coarse- and fine-grained turbidites deposited during sea-level falls and/or lowstands. The HC facies occur commonly associated with MHC facies. The HC facies may represent slope fans formed by mass-transport processes or gravity flows during sea-level falls and/or lowstands.

  8. Source and dispersal of suspended sediment in the macro-tidal Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaswamy, V.; Nath, B.N.; Vethamony, P.; Ilangovan, D.

    with the literature values of inter- preted source areas in Table 2. Geographic distribution map of Rb variation in the Gulf is shown in Fig. 8. Rb val- ues are higher toward the northern regions of the Gulf compared to the southern region and higher near the mouth... of Kachchh, during October–November 2002, range between 0.5 and 674 mg l C01 . Highly turbid waters are observed towards mouth of the Gulf, at the head of the Gulf and adjacent to numer- ous shoals present within the Gulf. Near-bottom SSC val- ues...

  9. Perspective on eastern migration studies: stopover ecology of migratory landbirds in the Gulf Coast region

    Science.gov (United States)

    Barrow, W.C.; Johnson Randall, L.A.

    2004-01-01

    Millions of Nearctic-Neotropical landbirds move through the coastal habitats of the Gulf of Mexico each spring and autumn as they migrate across and around the Gulf. Migration routes in the Gulf region are not static and they shift year to year and season to season according to prevailing wind patterns. Using data from field and radar studies, we mapped patterns of migration movement and landfall in the Gulf of Mexico region. Map categories include coastal areas where migrant numbers are consistently high, consistently common, sporadically common-abundant, sporadically common, or sparse. Weather surveillance radar data indicates that habitats along the Northwest Gulf Coast are consistently used each year.

  10. Gulf of Mexico Climate, Laurentide Ice Sheet History, and Global Sea Level Change During the Last Glacial Cycle

    Science.gov (United States)

    Flower, B. P.; Williams, C.; Brown, E. A.; Hastings, D. W.; Hill, H.; Adams, S.; Hendrix, J.; Martin, E. E.; Biller, N. B.; Goddard, E.

    2011-12-01

    The interactions between low-latitude Atlantic climate and high-latitude ice sheet variability represent an important issue in past abrupt climate change. Specifically, Laurentide Ice Sheet (LIS) meltwater input seems to be decoupled at the millennial scale from Gulf of Mexico sea-surface temperature (SST), as well as Greenland air temperature, during the last glacial cycle. Indeed, comparison to Greenland ice core records indicate significant meltwater input during some North Atlantic cool episodes, including Heinrich Stadials 4, 3, and 1. Here we present published and new Mg/Ca and δ18O data on the planktic foraminifer Globigerinoides ruber from northern Gulf of Mexico sediment cores that provide detailed records of SST, δ18O of seawater (δ18Osw), and inferred salinity for the 48-10 ka interval. Age control for Orca Basin cores MD02-2550 and -2551 is based on AMS 14C dates on G. ruber and documents continuous sedimentation at rates >35 cm/kyr. Significant meltwater input is inferred from δ18Osw data during Antarctic Isotope Maxima (AIM) events and reaches a peak during the Bølling/Allerød, consistent with bipolar warming and a high sensitivity to greenhouse forcing. Furthermore, bulk sediment δ18O data show a brief spike reaching -5.5% ca. 14.5 ka during an interval barren of foraminifera. We speculate that this excursion represents fine carbonate sediment from Canadian Paleozoic marine carbonates, analogous to detrital carbonate in the North Atlantic that has a δ18O value of -5%. Radiogenic isotope data (Nd and Pb) also reach peak values at this interval, indicative of older continental material sourced from Canada vs. younger material from the Mississippi River drainage basin. Inferred major meltwater flow appears to have been associated with meltwater pulse 1a within the Bølling warm interval, consistent with a significant contribution by the LIS to rapid global sea level rise. Overall, the relations between Gulf of Mexico meltwater input, Heinrich

  11. Inferring probable dispersal of Flower Garden Banks Coral Larvae (Gulf of Mexico) using observed and simulated drifter trajectories

    Science.gov (United States)

    Lugo-Fernández, Alexis; Deslarzes, Kenneth J. P.; Price, James M.; Boland, Gregory S.; Morin, Michelle V.

    2001-01-01

    We investigated likely coral larvae dispersal in the Gulf of Mexico by means of a combination of satellite-tracked drifters and simulated currents. Drifter data were collected during spawning events in 1997 and 1998 at the Flower Garden Banks (FGB) and from the "Surface Current and Lagrangian Drift Program" in 1993 (Niiler et al., Surface current and langrangian-drift program. Unpublished Report, U.S. Department of the Interior, Minerals Management Service, 1997, 10pp). Observed and simulated tracks showed that likely coral dispersal is driven by five circulation modes. Mode 1 is a cyclonic motion reaching the Texas shelf and possible cyclonic motion along the shelf toward Mexico. Mode 2 is an entrainment by offshore eddies causing likely larval transport into deep water (>200 m). Mode 3 consists of a continuous eastward movement that reaches 87.5°W. Mode 4 consists of recirculating flows over or near the FGB. Mode 5 is a cross-basin transport that ends near the Florida Keys in 50-60 days. Modes 1 and 4 can bring larvae back to the FGB within 24-30 days after spawning creating conditions for self-seeding. Offshore eddies near the FGB, Modes 2 and 5, generate offshore transport that can carry coral larvae to reefs in Mexico and Florida. Only ˜43% of the drifters leave the northwestern Gulf shelf, which implies that most coral larvae can remain on the shelf through Modes 1, 3, and 4. Mode 3 suggests eastward larval dispersal and under influence of the Mississippi River plume where they can be adversely affected by low salinity, low temperature, and high sedimentation which limit recruitment on oil and gas platforms. Possible effects of hurricanes on larval dispersal include reduced travel time, considerable displacements, and physical damage by strong turbulence. Nineteen outer shelf banks were contacted by actual and simulated drifter tracks, but only 10 are suitable for coral larvae settlement given the substrate and crest depth. These 10 banks could represent a

  12. [Effects mangrove conversion to pasture on density and shell size of two gastropods in the Turbo River Delta (Urabá Gulf, Caribbean coast of Colombia)].

    Science.gov (United States)

    Blanco, Juan F; Castaño, María C

    2012-12-01

    Mangrove deforestation is widespread in the Greater Caribbean but its impact on macrobenthos has not been evaluated to date. In order to assess the impact of mangrove conversion to pasture, densities and shell sizes of two dominant gastropods (Neritina virginea and Melampus coffeus) were compared among four mangrove types: 1) Rhizophora mangle-dominated fringing mangroves, 2) Avicennia germinans-dominated basin mangroves, 3) Mixed-species basin mangroves, and 4) A. germinans- basin mangroves converted to pastures, in the Turbo River Delta (Urabá Gulf, Colombia). Mangrove types were polygon-delimited with satellite images and color aerial photographs were taken in 2009. Various (nmangle-fringing mangroves. N. virginea density decreased gradually towards the A. germinans-basin mangroves seemly related to the diadromous life-history. This species nearly disappeared in the neighboring pastures because individuals were constrained to a few remaining flooded areas. In the pastures, M. coffeus individuals were clumped in the remaining A. germinans trees due to its climbing behavior as a pulmonate. We hypothesize that the decline of these two gastropods was related to physical microhabitat (e.g. trees, prop roots, and seedlings) degradation, and alteration of soil properties (e.g. temperature, pH, organic matter content). Finally, we also hypothesize that the local extinction of N. virginea due to clear-cutting may exert strong negative effects on the ecosystem function because it is a dominant omnivore. PMID:23342523

  13. Geologic assessment of undiscovered oil and gas resources: Oligocene Frio and Anahuac Formations, United States Gulf of Mexico coastal plain and State waters

    Science.gov (United States)

    Swanson, Sharon M.; Karlsen, Alexander W.; Valentine, Brett J.

    2013-01-01

    The Oligocene Frio and Anahuac Formations were assessed as part of the 2007 U.S. Geological Survey (USGS) assessment of Tertiary strata of the U.S. Gulf of Mexico Basin onshore and State waters. The Frio Formation, which consists of sand-rich fluvio-deltaic systems, has been one of the largest hydrocarbon producers from the Paleogene in the Gulf of Mexico. The Anahuac Formation, an extensive transgressive marine shale overlying the Frio Formation, contains deltaic and slope sandstones in Louisiana and Texas and carbonate rocks in the eastern Gulf of Mexico. In downdip areas of the Frio and Anahuac Formations, traps associated with faulted, rollover anticlines are common. Structural traps commonly occur in combination with stratigraphic traps. Faulted salt domes in the Frio and Anahuac Formations are present in the Houston embayment of Texas and in south Louisiana. In the Frio Formation, stratigraphic traps are found in fluvial, deltaic, barrier-bar, shelf, and strandplain systems. The USGS Tertiary Assessment Team defined a single, Upper Jurassic-Cretaceous-Tertiary Composite Total Petroleum System (TPS) for the Gulf Coast basin, based on previous studies and geochemical analysis of oils in the Gulf Coast basin. The primary source rocks for oil and gas within Cenozoic petroleum systems, including Frio Formation reservoirs, in the northern, onshore Gulf Coastal region consist of coal and shale rich in organic matter within the Wilcox Group (Paleocene–Eocene), with some contributions from the Sparta Sand of the Claiborne Group (Eocene). The Jurassic Smackover Formation and Cretaceous Eagle Ford Formation also may have contributed substantial petroleum to Cenozoic reservoirs. Modeling studies of thermal maturity by the USGS Tertiary Assessment Team indicate that downdip portions of the basal Wilcox Group reached sufficient thermal maturity to generate hydrocarbons by early Eocene; this early maturation is the result of rapid sediment accumulation in the early

  14. Large Scale Moisture Fluxes that are related to dry and wet conditions over Mediterranean Basin

    Science.gov (United States)

    Sahin, Sinan; Luterbacher, Juerg; Xoplaki, Elena; Turkes, Murat

    2016-04-01

    Large scale moisture flux analysis was carried out for the Mediterranean Basin in order to investigate the large scale atmospheric controls on moisture flux convergence that are related to dry and wet conditions. The seasonal moisture budget (precipitation minus evaporation) was calculated using the National Centers for Environmental Prediction - National Center for Atmospheric Research reanalysis data for the period 1949-2014. We focus on winter and summer circulation patterns for explaining the changes in dry and wet conditions rather than spring and autumn, as the transitional nature and characterization of these seasons are more uncertain in the Mediterranean basin. The driest and wettest years were chosen according to Standardized Precipitation Index (SPI) and the differences between those years and average conditions were compared statistically and graphically. According to results, large scale climate changes over Mediterranean Region are linked to significant changes of the moisture fluxes in the Gulf of Mexico region and partially in the US East coast especially for wet years. Therefore the climatic role of the Gulf Stream for extreme climate conditions over Mediterranean region should be investigated.

  15. Paleomagnetic evidence of oblique rift localization in the Gulf of California

    Science.gov (United States)

    Bennett, S. E.; Oskin, M. E.

    2012-12-01

    sites within the rift where both SF and MC are present in the same fault block, SF is rotated clockwise by a greater amount than MC. 7 of these 10 sites are precise enough to statistically isolate differential rotation. At paired sites, a weighted mean of 16° of clockwise rotation (maximum of 48°) occurred prior to 6.4 Ma. By weighting all paired site results by the differential rotation error, we estimate that 48% (locally 0% to 75%) of the net rotation occurred during the proto-Gulf time period (12.5 - 6 Ma) and prior to rift localization ca. 6 Ma. This early rotation occurred in a ~50-100 kilometer-wide belt of strike-slip faulting embedded within the wider Mexican Basin and Range extensional province, and connected to the San Andreas fault in southern California. Where extension is hosted within a strike-slip-dominated setting (i.e. oblique rift), the overall higher strain rates along shear zones and across the intervening extensional pull-apart basins may localize crustal thinning within an otherwise wide-rift setting, facilitating crustal rupture. By increasing strain rates and connecting areas of focused crustal thinning, strike-slip faulting may have catalyzed the subsequent formation of the Gulf of California

  16. Ocean Carbon and Biogeochemistry Scoping Workshop on Terrestrial and Coastal Carbon Fluxes in the Gulf of Mexico, St. Petersburg, FL, May 6-8, 2008

    Science.gov (United States)

    Robbins, L.L.; Coble, P.G.; Clayton, T.D.; Cai, W.J.

    2009-01-01

    Despite their relatively small surface area, ocean margins may have a significant impact on global biogeochemical cycles and, potentially, the global air-sea fluxes of carbon dioxide. Margins are characterized by intense geochemical and biological processing of carbon and other elements and exchange large amounts of matter and energy with the open ocean. The area-specific rates of productivity, biogeochemical cycling, and organic/inorganic matter sequestration are high in coastal margins, with as much as half of the global integrated new production occurring over the continental shelves and slopes (Walsh, 1991; Doney and Hood, 2002; Jahnke, in press). However, the current lack of knowledge and understanding of biogeochemical processes occurring at the ocean margins has left them largely ignored in most of the previous global assessments of the oceanic carbon cycle (Doney and Hood, 2002). A major source of North American and global uncertainty is the Gulf of Mexico, a large semi-enclosed subtropical basin bordered by the United States, Mexico, and Cuba. Like many of the marginal oceans worldwide, the Gulf of Mexico remains largely unsampled and poorly characterized in terms of its air-sea exchange of carbon dioxide and other carbon fluxes. In May 2008, the Ocean Carbon and Biogeochemistry Scoping Workshop on Terrestrial and Coastal Carbon Fluxes in the Gulf of Mexico was held in St. Petersburg, FL, to address the information gaps of carbon fluxes associated with the Gulf of Mexico and to offer recommendations to guide future research. The meeting was attended by over 90 participants from over 50 U.S. and Mexican institutions and agencies. The Ocean Carbon and Biogeochemistry program (OCB; http://www.us-ocb.org/) sponsored this workshop with support from the National Science Foundation, the National Oceanic and Atmospheric Administration, the National Aeronautics and Space Administration, the U.S. Geological Survey, and the University of South Florida. The goal of

  17. Holocene climate variability in the North-Western Mediterranean Sea (Gulf of Lions

    Directory of Open Access Journals (Sweden)

    B. Jalali

    2015-07-01

    Full Text Available Sea surface temperatures (SSTs and land-derived input time series were generated from the Gulf of Lions inner-shelf sediments (NW Mediterranean Sea using alkenones and high-molecular-weight odd-carbon numbered n-alkanes (TERR-alkanes, respectively. The SST record depicts three main phases: a warm Early Holocene (∼ 18 ± 0.4 °C followed by a cooling of ∼ 3 °C (from 7000 to 1000 BP and rapid warming from ∼ 1850 AD onwards. Several superimposed multi-decadal cooling events of ∼ 1 °C amplitude were also identified. TERR-alkanes were also quantified to identify periods of high river discharge in relation with flood events of the Rhone River and precipitations. Their concentrations show a broad increase from the early Holocene towards present with a pronounced minimum around 2500 BP and large fluctuations during the second part of the Holocene. Comparison with Holocene flood activity reconstructions across the Alps region suggests that sediments of the inner shelf originate mainly from the Upper Rhone River catchment basin and that they are primarily delivered during positive NAO.

  18. Numerical simulation of the Gulf Stream and Mid-Ocean eddies

    Science.gov (United States)

    Semtner, A. J., Jr.; Mintz, Y.

    1977-01-01

    Oceanographic field measurements have revealed intense, transient mesoscale motions in many parts of the world ocean. The circulation of the western North Atlantic, considered in the present study as a rectangular basin, is simulated with a primitive equation model that has five levels and a horizontal grid size of 37 km. The model ocean is driven by a 2.5 gyre pattern of steady zonal wind stress and by a Newtonian-type surface heating. Two cases are considered: the first uses a Laplacian formulation for the subgrid-scale lateral diffusions of heat and momentum; the second uses a highly scale-selective biharmonic formulation for these diffusions. An analysis of the heat transport, in the biharmonic experiment, shows that the horizontal transport of heat by eddies is much larger than the subgrid-scale horizontal heat diffusion. In the Gulf Stream region, the eddy heat transport is comparable to the effect of a lateral diffusion coefficient of 10 to the 7th sq cm/s.

  19. Rapid Sedimentation, Overpressure, and Focused Fluid Flow, Gulf of Mexico Continental Margin

    Directory of Open Access Journals (Sweden)

    Cédric M. John

    2006-09-01

    Full Text Available Expedition 308 of the Integrated Ocean Drilling Program (IODP was the fi rst phase of a two-component project dedicated to studying overpressure and fl uid fl ow on the continental slope of the Gulf of Mexico. We examined how sedimentation, overpressure, fl uid fl ow, and deformation are coupled in a passive margin setting and investigated how extremely rapid deposition of fi ne-grained mud might lead to a rapid build-up of pore pressure in excess of hydrostatic (overpressure, underconsolidation, and sedimentary masswasting. Our tests within the Ursa region, where sediment accumulated rapidly in the late Pleistocene, included the first-ever in situ measurements of how physical properties, pressure, temperature,and pore fluid compositions vary within low-permeability mudstones that overlie a permeable, overpressured aquifer, and we documented severe overpressure in the mudstones overlying the aquifer. We also drilled and logged three references sites in the Brazos-Trinity Basin IV and documented hydrostatic pressure conditions and normalconsolidation. Post-expedition studies will address how the generation and timing of overpressure control slope stability, seafl oor seeps, and large-scale crustal fluid fl ow. The operations ofExpedition 308 provide a foundation for future long-term in situ monitoring experiments in the aquifer and bounding mudstones.

  20. Distributions and accumulation rates of polycyclic aromatic hydrocarbons in the northern Gulf of Mexico sediments.

    Science.gov (United States)

    Adhikari, Puspa L; Maiti, Kanchan; Overton, Edward B; Rosenheim, Brad E; Marx, Brian D

    2016-05-01

    Sediment samples collected from shelf, slope and interior basin of the northern Gulf of Mexico during 2011-2013, 1-3 years after the Deepwater Horizon (DWH) oil spill, were utilized to characterize PAH pollution history, in this region. Results indicate that the concentrations of surface ΣPAH43 and their accumulation rates vary between 44 and 160 ng g(-1) and 6-55 ng cm(-2) y(-1), respectively. ΣPAH43 concentration profiles, accumulation rates and Δ(14)C values are significantly altered only for the sediments in the immediate vicinity of the DWH wellhead. This shows that the impact of DWH oil input on deep-sea sediments was generally limited to the area close to the spill site. Further, the PAHs source diagnostic analyses suggest a noticeable change in PAHs composition from higher to lower molecular weight dominance which reflects a change in source of PAHs in the past three years, back to the background composition. Results indicate low to moderate levels of PAH pollution in this region at present, which are unlikely to cause adverse effects on benthic communities. PMID:26895564