WorldWideScience

Sample records for andesitic terrains dominica

  1. Dominica.

    Science.gov (United States)

    Barrie, Francois

    Dominica is the largest and least densely populated of the islands of the Organization of Easter Caribbean States. This paper provides a socioeconomic overview of Dominica and highlights the nation's efforts to comply with the provisions of the United Nations Convention on the Rights of the Child (CRC). The paper provides data on population, sex…

  2. Evidence of equilibrium peak runoff rates in steep tropical terrain on the island of Dominica during Tropical Storm Erika, August 27, 2015

    Science.gov (United States)

    Ogden, Fred L.

    2016-11-01

    Tropical Storm Erika was a weakly organized tropical storm when its center of circulation passed more than 150 km north of the island of Dominica on August 27, 2015. Hurricane hunter flights had difficulty finding the center of circulation as the storm encountered a high shear environment. Satellite and radar observations showed gyres imbedded within the broader circulation. Radar observations from Guadeloupe show that one of these gyres formed in convergent mid-level flow triggered by orographic convection over the island of Dominica. Gauge-adjusted radar rainfall data indicated between 300 and 750 mm of rainfall on Dominica, most of it over a four hour period. The result was widespread flooding, destruction of property, and loss of life. The extremity of the rainfall on steep watersheds covered with shallow soils was hypothesized to result in near-equilibrium runoff conditions where peak runoff rates equal the watershed-average peak rainfall rate minus a small constant loss rate. Rain gauge adjusted radar rainfall estimates and indirect peak discharge (IPD) measurements from 16 rivers at watershed areas ranging from 0.9 to 31.4 km2 using the USGS Slope-Area method allowed testing of this hypothesis. IPD measurements were compared against the global envelope of maximum observed flood peaks versus drainage area and against simulations using the U.S. Army Corps of Engineers Gridded Surface/Subsurface Hydrologic Analysis (GSSHA) model to detect landslide-affected peak flows. Model parameter values were estimated from the literature. Reasonable agreement was found between GSSHA simulated peak flows and IPD measurements in some watersheds. Results showed that landslide dam failure affected peak flows in 5 of the 16 rivers, with peak flows significantly greater than the envelope curve values for the flood of record for like-sized watersheds on the planet. GSSHA simulated peak discharges showed that the remaining 11 peak flow values were plausible. Simulations of an

  3. District nursing in Dominica

    NARCIS (Netherlands)

    Kolkman, PME; Luteijn, AJ; Nasiiro, RS; Bruney, [No Value; Smith, RJA; Meyboom-de Jong, B

    1998-01-01

    District nurses constitute the basis of the primary health care services in Dominica. All encounters of three district nurses were registered using the international classification of primary care. Information on other aspects of district nursing was collected by participating observation and the us

  4. District nursing in Dominica

    NARCIS (Netherlands)

    Kolkman, PME; Luteijn, AJ; Nasiiro, RS; Bruney, [No Value; Smith, RJA; Meyboom-de Jong, B

    1998-01-01

    District nurses constitute the basis of the primary health care services in Dominica. All encounters of three district nurses were registered using the international classification of primary care. Information on other aspects of district nursing was collected by participating observation and the

  5. Giambattista Bodoni’s Oratio Dominica

    Directory of Open Access Journals (Sweden)

    Valentino Romani

    2013-12-01

    Full Text Available Giambattista Bodoni is certainly one of the most influential character of the late eighteenth century. His skill as a printer played a crucial role in his reputation among some of the most important and influential European politicians, diplomats, and scholars. He also granted glory and fame to the city of Parma thanks to his ducal printing house. His skill as a printer was particularly improved during his stay in Rome, between 1758 and 1766, under the supervision of Costantino Ruggeri in the printing house of Propaganda Fide. In 1805, on the spur of Pius VII, Bodoni undertook one of his most famous enterprise, the Oratio Dominica CL linguis versa, et propriis cuiusque linguae characteribus plerumque expressa. The work was conceived as a reaction to Pater Poliglotto, published in the French Imperial typography directed by Jean-Joseph Marcel and offered to the Pope in January of the same year. This French version was made in large part thanks to punches and matrix confiscated precisely at the Typography of Propaganda Fide, and carried to Paris in 1798. The result of Bodoni’s work was extraordinary; the Oratio Dominica, dedicated to Eugene de Beauharnais and Augusta Amelia, was even acknowledged at the Paris Industrial Exposition in 1806.

  6. Tardigrada of the Caribbean island of Dominica (West Indies

    Directory of Open Access Journals (Sweden)

    Juliana G. Hinton

    2013-05-01

    Full Text Available In June 2009 we surveyed the terrestrial Tardigrada of Dominica, the most northerly of the Windward islands of the Lesser Antilles in the Caribbean sea. Out of 112 moss, lichen, liverwort and leaf litter samples, 35 had tardigrades, representing 10 genera and 25 species or species groups. This survey increases the number of species reported from Dominica from 3 to 25, more than the total recorded from any other West Indian island. Twelve species found in Dominica are cosmopolitan or belong to cosmopolitan species groups. Eight species are new to the fauna of the West Indies, one is new to the fauna of the Americas, and at least one is endemic to Dominica.

  7. Suscetibilidade de Rhyzopertha dominica (Fabricius (Coleoptera: Bostrichidae ao enxofre Susceptibility of Rhyzopertha dominica (Fabricius (Coleoptera: Bostrichidae to sulfur

    Directory of Open Access Journals (Sweden)

    José Roberto Gonçalves

    2007-08-01

    Full Text Available As criações de Rhyzopertha dominica (Fabricius (Coleoptera: Bostrichidae são freqüentemente infestadas pelo ácaro Acarophenax lacunatus (Cross e Krantz (Prostigmata: Acarophenacidae. O objetivo deste trabalho foi avaliar doses de enxofre, acaricida eficaz contra A. lacunatus, não-prejudiciais ao desenvolvimento de R. dominica. As unidades experimentais foram constituídas de placas de Petri contendo 30 g de grãos de trigo infestados com 30 adultos de R. dominica. Os tratamentos consistiram na utilização de doses de enxofre sobre os grãos, correspondentes a 0,0; 0,6; 0,9; 1,2; 1,5; 3,0; 6,0; 12,0; 24,0 e 48,0mg i a g-1, em dez repetições. As unidades experimentais foram armazenadas por 60 dias a 30±1°C, 60±5% UR e escotofase de 24h. O desenvolvimento de R. dominica foi afetado pela utilização de doses de enxofre maiores que 3,0mg i a g-1.The laboratory rearing of Rhyzopertha dominica (Fabricius (Coleoptera: Bostrichidae is frequently infested by the parasite mite Acarophenax lacunatus (Cross and Krantz (Prostigmata: Acarophenacidae. This study was aimed at evaluating the sulfur doses, an effective acaricide against A. lacunatus, not harmful to the development of with R. dominica. The experimental units were Petri dishes containing 30g of whole wheat grains powdered with the different doses of the sulfur (0.0, 0.6, 0.9, 1.2, 1.5, 3.0, 6.0, 12.0, 24.0 and 48.0mg a i g-1 infested with 30 adults of R. dominica, in ten replicates. All treatments were maintained under controlled conditions (30±1°C, 60±5% r h and 24h scotophase for 60 days after the insect infestation. Sulfur doses higher than 3.0mg a i g-1 negatively affected R. dominica development.

  8. Late Holocene Andesitic Eruptions at Mount Rainier

    Science.gov (United States)

    Sisson, T. W.; Vallance, J. W.

    2005-12-01

    Holocene Mt. Rainier erupted much more frequently than is recorded by its 11 pumiceous tephras. In the 2.6-2.2 ka Summerland eruptive period, 6 groups of thin (1-5 mm) Sparsely Vesicular Glassy (SVG) ashes were deposited (S1-S6), followed by the 0.3 km3 C-tephra. Two groups of andesitic lava flows and one andesitic block-and-ash flow (2.45 ka) also erupted in the Summerland period (ice conceals any other products). Based on glass composition the pyroclastic flow correlates with S4 ashes that also contain pumiceous grains and rare pumice lapilli. The first of the lava groups, exposed in windows through the Emmons and Winthrop glaciers, is Sr-rich for Mt. Rainier eruptives and correlates with S5 & S6 ashes based on similar high-Sr plagioclase. The ensuing C-tephra formed by plinian eruption of mixed and mingled magma comprising 4 juvenile components: mixed porphyritic andesite pumice, crystal-poor andesite scoria, vesicular high-Sr dacite blebs in pumice and scoria, and poorly inflated crystal-rich high-Sr dacite. High-Sr components were probably entrained conduit linings and segregations from the preceding high-Sr eruptions. The youngest lava group, exposed at the summit, is normal-Sr andesite lacking mixing textures of the C-tephra, and represents eruption of another small batch of andesitic magma perhaps just after the C event. SVG ash grains have blocky-to-fluidal shapes, are rich in plagioclase microlites, and their glasses are high-SiO2 (66-78%) and low-Al2O3 (15-11%). Melting experiments yield apparent equilibration pressures <50MPa for SVG liquids. SVG ashes likely result from shallow hydromagmatic explosions as largely degassed magmas transited the upper-edifice hydrothermal system during effusive eruptions. Rare pumice lapilli codeposited with S1, S2, and S4 ashes have microlite-free dacitic glasses, one with nonreacted hbl phenocrysts. These pumice formed from magmas that ascended rapidly from reservoir depths, synchronous with or closely between effusive

  9. Spatial and Temporal Clustering of Chikungunya Virus Transmission in Dominica.

    Directory of Open Access Journals (Sweden)

    Elaine O Nsoesie

    Full Text Available Using geo-referenced case data, we present spatial and spatio-temporal cluster analyses of the early spread of the 2013-2015 chikungunya virus (CHIKV in Dominica, an island in the Caribbean. Spatial coordinates of the locations of the first 417 reported cases observed between December 15th, 2013 and March 11th, 2014, were captured using the Global Positioning System (GPS. We observed a preponderance of female cases, which has been reported for CHIKV outbreaks in other regions. We also noted statistically significant spatial and spatio-temporal clusters in highly populated areas and observed major clusters prior to implementation of intensive vector control programs suggesting early vector control measures, and education had an impact on the spread of the CHIKV epidemic in Dominica. A dynamical identification of clusters can lead to local assessment of risk and provide opportunities for targeted control efforts for nations experiencing CHIKV outbreaks.

  10. Walking stability of Rhyzopertha dominica (Fabricius, 1792 (Coleoptera: Bostrichidae

    Directory of Open Access Journals (Sweden)

    E. M. Pires

    Full Text Available Abstract Results obtained in studies can contribute to the advancement of science and innovative methods and techniques for developing practical activities. Reporting conditions that may restrict the implementation of research is critical to ensure the optimal development of further technical studies. The objective of this study was to assess the walking stability of R. dominica on a flat and smooth surface. The study was based on the determination of mortality, morphology and walking stability of the insect outside the grain mass, on a flat and smooth surface. Mortality of adults of this Coleoptera in conditions with and without food was similar, which explains the difficulty that this insect had for accessing the food source on the flat and smooth surface. The measurements of body length (BOL, width (BOW and height (BOH of R. dominica were compared with those of Tribolium castaneum (Coleoptera: Tenebrionidae, which showed good ability to walk in these conditions. This study indicated that the former presents lower BOL and BOW, and greater BOH than the second, and all these variables showed differences when analyzed simultaneously by means of the construction of multivariate morphometric indices (Width × Height, Length × Height and Height × Length × Width. These morphometric variables, together with the definition of the geometry most similar to the body shape, resulted in determination of the center of gravity (CG and static rollover threshold (SRTgeom for both species. Rhyzopertha dominica and T. castaneum presented CGs considered high and low, respectively, and together with the values obtained for SRTgeom, may justify that R. dominica can be considered a less stable species during movement, and presents greater risk of rollover on flat and smooth surfaces.

  11. A sustainability analysis of geothermal energy development on the island of Dominica

    Science.gov (United States)

    Edwards, Kiyana Marie-Jose

    Dominica is heavily dependent on fossil fuels to meet its electricity generation needs. Dominica's volcanic origin and current volcanic activity allow the island to be an ideal place for the production of geothermal energy. Once geothermal exploration and development has begun in Dominica, it is uncertain whether the efforts will produce an environmentally, economically and socially feasible exploitation of the resource. Using content analysis and cost benefit analysis, this study examined the impacts of geothermal energy development based on the triple bottom line of sustainability for the Wotten Waven community, as well as the island as a whole. The results indicate that this project will have an overall positive impact on the triple bottom line of sustainability for Dominica. Therefore, geothermal energy may provide substantial net benefits to economic and sustainable development of the island. Assessing the sustainability of geothermal development is important as Dominica begins to produce geothermal energy.

  12. Chaotic Terrain

    Science.gov (United States)

    2003-01-01

    [figure removed for brevity, see original site] Released 4 June 2003Chaotic terrain on Mars is thought to form when there is a sudden removal of subsurface water or ice, causing the surface material to slump and break into blocks. The chaotic terrain in this THEMIS visible image is confined to a crater just south of Elysium Planitia. It is common to see chaotic terrain in the vicinity of the catastrophic outflow channels on Mars, but the terrain in this image is on the opposite side of the planet from these channels, making it somewhat of an oddity.Image information: VIS instrument. Latitude -5.9, Longitude 108.1 East (251.9 West). 19 meter/pixel resolution.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  13. The distribution of seagrasses in Dominica, Lesser Antilles.

    Science.gov (United States)

    Steiner, S C C; Macfarlane, K J; Price, L M; Willette, D A

    2010-10-01

    Seagrass beds are the largest organism-built marine habitat in Dominica, yet have only been surveyed since 2007. Standardized examinations along a depth gradient between 0 and 24 m, focusing on magnoliophyte species composition and benthic cover of shoots at 17 seagrass bed sites, were carried out between September 10 and December 7, 2008. The Cymodoceaceae Syringodium filiforme (Kuetzing 1860) and Halodule wrightii (Ascherson 1868), as well as the Hydrocharitaceae Halophila decipiens (Ostenfeld 1902), H. stipulacea (Fosskal & Ascherson 1867) and Thalassia testudinum (Banks ex König 1805) displayed distinct regional and horizontal distribution patterns. Syringodium filiforme is the island's dominant seagrass along the western and northern coasts, occurring at depths between 2 and 18 m and with a mean benthic cover ranging from 0.9-10% along the West coast. Along the North coast it grew between 0.2 and 1 m depth with a mean maximum benthic cover of 48.9%. Halodule wrightii grew along the North and West coasts, in depths between 1 and 14m in areas of recent and chronic disturbances. Its delicate morphology and sparse benthic cover (< 0.1%) did not constitute seagrass beds. Halophila decipiens grew along the deep, shallow and lateral margins of west coast S. filiforme beds and monospecifically in depths between 3 and 24m. Halophila stipulacea, an invasive species, was widespread along 45km of the West coast and was found in depths between 5 and 24m. Both Halophila species formed extensive beds at depths beyond the survey limit of 24m thus playing a potentially important role in the resettlement of shallow areas after storms. H. decipiens and H. stipulacea are currently the second and third most common seagrasses on the island respectively, despite their absence along the North coast. T. testudinum was confined to North coast's sheltered reef flats at depths Im or less with mean a benthic cover ranging from 2 to 76%. It grew monospecifically in the most turbulent and

  14. ACUERDO DE COOPERACIÓN ENERGÉTICA PETROCARIBE. CASO: COMMONWEALTH DE DOMINICA

    Directory of Open Access Journals (Sweden)

    Dani José Villalobos Soto

    2014-05-01

    Full Text Available Latinamerica and the Caribbean has become the primary focus of the energy cooperation that has proposed the Bolivarian Republic of Venezuela for the region in the context of new paradigms Integration today that expresses the dynamics of the Latin American and Caribbean countries. This research has as its sole proposto present the behavior of the trade balance of the Commonwealth of Dominica to the Energy Cooperation Agreement PETROCARIBE. The overall objective is primarily focused on examining the exports and imports present in the trade balance of the Commonwealth of Dominica in the period 2003-2007. The study of this research is being conducted through a type of documentary research-descriptive bibliographic under design. It is concluded that the Petrocaribe agreement Dominica benefits as it allows you to access resources given fossil contentivas payment arrangements in the agreement

  15. The distribution of seagrasses in Dominica, Lesser Antilles

    Directory of Open Access Journals (Sweden)

    S.C.C Steiner

    2010-10-01

    Full Text Available Seagrass beds are the largest organism-built marine habitat in Dominica, yet have only been surveyed since 2007. Standardized examinations along a depth gradient between 0 and 24m, focusing on magnoliophyte species composition and benthic cover of shoots at 17 seagrass bed sites, were carried out between September 10 and December 7, 2008. The Cymodoceaceae Syringodium filiforme (Kuetzing 1860 and Halodule wrightii (Ascherson 1868, as well as the Hydrocharitaceae Halophila decipiens (Ostenfeld 1902, H. stipulacea (Fosskal & Ascherson 1867 and Thalassia testudinum (Banks ex König 1805 displayed distinct regional and horizontal distribution patterns. Syringodium filiforme is the island’s dominant seagrass along the western and northern coasts, occurring at depths between 2 and 18m and with a mean benthic cover ranging from 0.9-10% along the West coast. Along the North coast it grew between 0.2 and 1m depth with a mean maximum benthic cover of 48.9%. Halodule wrightii grew along the North and West coasts, in depths between 1 and 14m in areas of recent and chronic disturbances. Its delicate morphology and sparse benthic cover (Pastos marinos son los ambientes más grandes constituidos por organismos en Dominica. Sin embargo, sólo se han examinado desde 2007. Entre el 10 de septiembre y 9 de diciembre 2008, se examinaron la composicion de especies y la densidad de magnoliofitas en profundidades de 0 a 24m. Los Cymodoceaceae: Syringodium filiforme y Halodule wrightii, tal como los Hydrocharitaceae: Halophila decipiens, H. stipulacea y Thalassia testudinum, mostraron una distribución regional y horizontal muy distinta. Syringodium filiforme fue la especie dominante en las costas del oeste y del norte de la isla. Se encontró en profundidades de 2 a 18m y con un promedio de cobertura béntica de 0.9-10% en la costa del oeste. En las costas del norte creció entre 0.2 y 1m de profundidad con un pormedio de cobertura béntica de 48.9%. Halodule

  16. OBSTETRICAL CONDITION AND NEONATAL NEUROLOGICAL OUTCOME IN DOMINICA, THE CARIBBEAN - A COMPARATIVE-STUDY

    NARCIS (Netherlands)

    VANDERVEERE, CN; LUTEYN, AJ; SORHAINDO, BA; FERREIRA, CJ; BOERSMA, ER; HUISJES, HJ; TOUWEN, BCL; HADDERSALGRA, M

    1992-01-01

    Risk factors during pregnancy and delivery and neurological morbidity of newborns were assessed in a birth cohort in Dominica, the Caribbean. The data were compared with two reference groups, one from Grenada, the Caribbean, and the other from Groningen, the Netherlands. Despite variations in cultur

  17. [Prime Ministers Eugenia Charles of Dominica, Margaret Thatcher and Indira Gandhi

    OpenAIRE

    Cooper, Neil

    2004-01-01

    207 x 153 mm. A photograph showing Eugenia Charles, Prime Minister of Dominica, Margaret Thatcher, British Prime Minister, and Indira Gandhi, Indian Prime Minister, with Tom Adams, Prime Minister of Barbados, and Lester Bird, Deputy Prime Minister and Foreign Minister of Antigua and Barbuda, behind them. The delegates are pictured at Fort Aguada, Goa.

  18. Health status of the elderly in the Marigot Health District, Dominica

    NARCIS (Netherlands)

    Veen-de Vries, N.R.; Luteijn, A.J.; Nasiiro, R.S.; Meyboom-de Jong, B.

    The health status and the prevalence of hypertension, diabetes mellitus, glaucoma and visual disorders of 123 elderly people (56 men, 67 women) in the Marigot Health District, Dominica, were assessed by means of four questionnaires, collection of data from their medical records; physical

  19. The land Mollusca of Dominica (Lesser Antilles), with notes on some enigmatic or rare species

    NARCIS (Netherlands)

    Robinson, D.G.; Hovestadt, A.; Fields, A.; Breure, A.S.H.

    2009-01-01

    An overview of the land-snail fauna of the Lesser Antillean island of Dominica is given, based on data from literature and four recent surveys. There are 42 taxa listed, of which the following species are recorded for the first time from the island: Allopeas gracile (Hutt on, 1834), A. micra (d’Orbi

  20. Health status of the elderly in the Marigot Health District, Dominica

    NARCIS (Netherlands)

    Veen-de Vries, N.R.; Luteijn, A.J.; Nasiiro, R.S.; Meyboom-de Jong, B.

    1999-01-01

    The health status and the prevalence of hypertension, diabetes mellitus, glaucoma and visual disorders of 123 elderly people (56 men, 67 women) in the Marigot Health District, Dominica, were assessed by means of four questionnaires, collection of data from their medical records; physical examination

  1. Haromyia, a new genus of long-legged flies from Dominica (Diptera: Dolichopodidae)

    Science.gov (United States)

    Justin B. Runyon

    2015-01-01

    The new micro-dolichopodid genus Haromyia gen. nov. and the type species H. iviei sp. nov. are described from the island of Dominica in the Lesser Antilles. Males and females of Haromyia are distinguished by the large setae on a bulging clypeus, minute size, and wing veins that are nearly straight and evenly diverging from wing base. Haromyia does not fit readily into...

  2. Formation of hybrid arc andesites beneath thick continental crust

    Science.gov (United States)

    Straub, Susanne M.; Gomez-Tuena, Arturo; Stuart, Finlay M.; Zellmer, Georg F.; Espinasa-Perena, Ramon; Cai, Yue; Iizuka, Yoshiyuki

    2011-03-01

    Andesite magmatism at convergent margins is essential for the differentiation of silicate Earth, but no consensus exists as to andesite petrogenesis. Models proposing origin of primary andesite melts from mantle and/or slab materials remain in deadlock with the seemingly irrefutable petrographic and chemical evidence for andesite formation through mixing of basaltic mantle melts with silicic components from the overlying crust. Here we use 3He/4He ratios of high-Ni olivines to demonstrate the mantle origin of basaltic to andesitic arc magmas in the central Mexican Volcanic Belt (MVB) that is constructed on ~ 50 km thick continental crust. We propose that the central MVB arc magmas are hybrids of high-Mg# > 70 basaltic and dacitic initial mantle melts which were produced by melting of a peridotite subarc mantle interspersed with silica-deficient and silica-excess pyroxenite veins. These veins formed by infiltration of reactive silicic components from the subducting slab. Partial melts from pyroxenites, and minor component melts from peridotite, mix in variable proportions to produce high-Mg# basaltic, andesitic and dacitic magmas. Moderate fractional crystallization and recharge melt mixing in the overlying crust produces then the lower-Mg# magmas erupted. Our model accounts for the contrast between the arc-typical SiO2 variability at a given Mg# and the strong correlation between major element oxides SiO2, MgO and FeO which is not reproduced by mantle-crust mixing models. Our data further indicate that viscous high-silica mantle magmas may preferentially be emplaced as intrusive silicic plutonic rocks in the crust rather than erupt. Ultimately, our results imply a stronger turnover of slab and mantle materials in subduction zones with a negligible, or lesser dilution, by materials from the overlying crust.

  3. FUMIGATION TOXICITY OF ESSENTIAL OILS AGAINST Rhyzopertha dominica (F. IN STORED MAIZE GRAIN

    Directory of Open Access Journals (Sweden)

    VALDEANY NÚBIA DE SOUZA

    2016-01-01

    Full Text Available The Rhyzopertha dominica F. (Coleoptera: Bostrichidae is a primary pest of stored grains in many regions of the world. In this work we evaluated the fumigant activity of essential oils of Ocimum basilicum L., Citrus aurantium L., Mentha spicata L. and Croton pulegiodorus Baill on adult R. dominica in stored maize. Tests were conducted to determine lethals concentrations (CL50 and CL100 and mortality (fumigation.The fumigation test was done in containers made of glass containing 10 individuals of R. dominica, where essential oils were applied at different concentrations: O. basilicum and M. spicata (5, 10, 15, 20, 30 and 40μL/L of air, C. aurantium (10, 20, 30, 40, 50 and 60μL/L of air and C. pulegiodorus (0, 20, 30, 50, 70 and 90μL/L of air. After 48 hours of exposure to the oils the percentage of insect mortality was evaluated. According to LC50 and LC100 the toxicity of essential oils decreased in the following order: O. basilicum> M. spicata> C. pulegiodorus> C. aurantium. The essential oil of O. basilicum exhibited strong fumigant toxicity against R. dominica adults, with a LC50 value of 17.67 μL/L air and LC100 value of 27.15 μL/ L air. The C. aurantium essential oil required higher concentrations than O. basilicum, M. spicata and C. pulegiodorus to kill insects. However, all oils evaluated presented fumigating property to promote the control of R. dominica and demonstrated potential use in the management of this coleoptera.

  4. Ethnomedicine of menstruation in rural Dominica, West Indies.

    Science.gov (United States)

    Flores, Katherine E; Quinlan, Marsha B

    2014-05-14

    In Dominica, women offer dysmenorrhea, delayed menses, and menorrhagia as prevalent menstrual troubles. Dominican humoral theory considers menstruation to be "hot" such that menstrual problems are caused by the introduction of too much "cold" in the body. These conditions can be painful and may require herbal medicine. Our method finds the most culturally salient plants for these conditions-those which are of common knowledge across the population. We hypothesize that cultural agreement on ethnobotanical treatments (1) reflects their perceived ethnophysiological efficacy, and that (2) salient plants contain bioactive compounds appropriate for the menstrual conditions for which Dominicans employ the plants. Qualitative data on local explanatory models and treatment of menstrual conditions were collected using participant-observation, focus groups, and informal key informant interviews. Quantitative ethnobotanical data come from freelist (or "free-list") tasks, conducted with 54 adults. Mean salience values calculated from freelisted data reveal that the same four plants, Cinnamomum verum (synonym Cinnamomum zeylanicum) (Lauraceae), Mentha suaveolens (Lamiaceae), Pimenta racemosa (Myrtaceae) and Sphagneticola trilobata (synonym Wedelia trilobata) (Asteraceae) are used to treat dysmenorrhea and delayed menses. The only remedy reported for menorrhagia, Sphagneticola trilobata (Asteraceae), is also a treatment for dysmenorrhea and delayed menses. The Dominican humoral system views menstruation as a "hot" condition, yet these "bush medicines" are also "hot." Dominicans do not view menstruation as a problem, rather, they reckon that excess "cold" in a woman׳s menstruating body impedes menstrual function to cause problems thus requiring "hot" plants to alleviate their symptoms. A literature review revealed that all four plants contain analgesic, anti-nociceptive, and anti-inflammatory properties. Additionally, Mentha suaveolens is muscle-relaxing and anti

  5. Late Tertiary andesites and basaltic andesites from Khangai, Khingan, and Vitim Plateau: geochemical similarities and differences of sources

    Science.gov (United States)

    Rudneva, Nadezhda; Chuvashova, Irina; Rasskazov, Sergei; Yasnygina, Tatiana

    2015-04-01

    Andesite is a typical rock of island arcs and active continental margins. This kind of volcanic rocks is not characteristic for inner parts of continents. Andesites and associated rocks (basaltic andesites, trachyandesites, basaltic trachyandesites) were identified, however, in many Cenozoic volcanic fields of Inner Asia, which was never referred to the mentioned geodynamic settings. To define geodynamic meaning of andesites and related rocks, we present isotopic and geochemical systematics of their sources for three key areas: Khangai, Khingan, and Vitim Plateau. Low-K andesite and basaltic trachyandesite lavas from East Khangai erupted at about 7-6 Ma from lower crustal source with enriched isotopic signatures of Nd and Sr and were followed by high-K mantle-derived basaltic lavas at 5.5-4.8 Ma that show depleted signature in terms of Sr isotopes and enriched one in terms of Nd isotopes. This lava sequence is indicative for delamination of the lower lithosphere beneath the East Khangai orogenic province. Andesite, basaltic andesite, trachyandesite, and basalt lavas from Greater and Lesser Khingan, which are characterized by wide variations of K2O/Na2O ratios, erupted in different areas of the Greater and Lesser Khingan in the time interval from 22 to 1 Ma from heterogeneous crustal and mantle sources with enriched isotopic signatures of Nd and Sr. Unlike the crust-mantle magma-generated processes beneath East Khangai, those beneath Khingan were dispersed in time and space. Basaltic andesite lavas from Vitim Plateau, erupted at 14-13 Ma after high-Mg basanites and picrobasalts, show depleted isotopic signatures of Nd and Sr. In terms of trace-element modeling, lavas of this unit were derived through high-degree partial melting (15-20 %) in the shallow (garnet-free) mantle lithospheric source. The found geochemical grouping of rocks is considered as the basis for systematics of shallow mantle and crustal sources of Cenozoic volcanic rocks from different regions of

  6. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    Science.gov (United States)

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

  7. Terrain-Toolkit

    DEFF Research Database (Denmark)

    Wang, Qi; Kaul, Manohar; Long, Cheng

    2014-01-01

    , as will be shown, is used heavily for query processing in spatial databases; and (3) they do not provide the surface distance operator which is fundamental for many applications based on terrain data. Motivated by this, we developed a tool called Terrain-Toolkit for terrain data which accepts a comprehensive set...

  8. Interpretation of the relations between massive, pillowed and brecciated facies in an archean submarine andesite volcano — amulet andesite, rouyn-noranda, Canada

    Science.gov (United States)

    Cousineau, Pierre; Dimroth, Erich

    1982-07-01

    The Amulet andesite formation in the Archean terrain of Rouyn-Noranda, P.Q., consists of 19 flows, distinguished by variations in phenocryst content and vesicularity and by the presence of concentric contraction fractures. Detailed mapping of flows revealed the presence of three main facies: (1) massive facies; (2) pillowed facies; and (3) foreset-bedded (brecciated) facies. The massive facies consists of > 50% massive lava overlain by pillow lava and/or pillow breccia. The pillowed facies consists of > 50% pillows. In some flows, the pillowed facies contains a thin sheet of massive lava at the base of the flow (facies 2a). Generally, massive lava fills braided channels 10-50 m wide (facies 2b). Facies 2c consists of pillows and large, irregular, megapillows. Determination of the flow direction shows that facies 1 is proximal, facies 2 distal. The foreset-bedded facies 3 consists of alternating thin (1-2 m) lobes of massive lava, pillow lava and broken-pillow breccia. It makes up flows 16-19 at the top of the sequence. Flow M, a unit entirely composed of massive lava, is ponded against flows 9 and 10. We interpret the growth of the Amulet andesite volcano in the light of new work on ocean-floor basalt and on the 1969-1973 Mauna Ulu eruption. The feeding fissure was located in the area of massive facies. At the beginning of eruptions lava spread laterally as a sheet-flood flow (massive base of facies 2a) but rapidly became channelized. The pillow lava and in particular the facies 2b, 2c and 3 are considered as the subaqueous equivalents of tube-fed pahoehoe. Flow M probably represents a lava lake. Shallowing-upward of the sequence during the built-up of the volcano is indicated by increasing vesicularity of the flows and by an upward increase of the proportion of broken pillow breccia. This increase is gradual from flow 1 to flow 15 but abrupt from flow 15 to 16-19.

  9. Phosphine resistance in Tribolium castaneum and Rhyzopertha dominica from stored wheat in Oklahoma.

    Science.gov (United States)

    Opit, G P; Phillips, T W; Aikins, M J; Hasan, M M

    2012-08-01

    Phosphine gas, or hydrogen phosphide (PH3), is the most common insecticide applied to durable stored products worldwide and is routinely used in the United States for treatment of bulk-stored cereal grains and other durable stored products. Research from the late 1980s revealed low frequencies of resistance to various residual grain protectant insecticides and to phosphine in grain insect species collected in Oklahoma. The present work, which used the same previously established discriminating dose bioassays for phosphine toxicity as in the earlier study, evaluated adults of nine different populations of red flour beetle, Tribolium castaneum (Herbst), and five populations of lesser grain borer, Rhyzopertha dominica (F.) collected from different geographic locations in Oklahoma. One additional population for each species was a laboratory susceptible strain. Discriminating dose assays determined eight out of the nine T. castaneum populations, and all five populations of R. dominica, contained phosphine-resistant individuals, and highest resistance frequencies were 94 and 98%, respectively. Dose-response bioassays and logit analyses determined that LC99 values were approximately 3 ppm for susceptible and 377 ppm for resistant T. castaneum, and approximately 2 ppm for susceptible and 3,430 ppm for resistant R. dominica. The most resistant T. castaneum population was 119-fold more resistant than the susceptible strain and the most resistant R. dominica population was over 1,500-fold more resistant. Results suggest a substantial increase in phosphine resistance in these major stored-wheat pests in the past 21 yr, and these levels of resistance to phosphine approach those reported for other stored-grain pest species in other countries.

  10. Life stage and resistance effects in modelling phosphine fumigation of Rhyzopertha dominica (F.)

    OpenAIRE

    Thorne, J.; Fulford, G.; Ridley, A.; Schlipalius, D.; P. Collins

    2010-01-01

    Resistance to phosphine in insect pests of stored grain is a serious problem and there is a world-wide need for the development of sustainable resistance management strategies. Here we introduce results from a new mathematical model of resistance development that includes all life stages, rates of oviposition, natural mortality and mortality under fumigation in relation to resistant genotype. The example we discuss is phosphine resistance in the lesser grain borer, Rhyzopertha dominica where ...

  11. Genotoxic studies of selected plant oil extracts on Rhyzopertha dominica (Coleoptera: Bostrichidae

    Directory of Open Access Journals (Sweden)

    Sameer H. Qari

    2017-05-01

    Full Text Available This study was conducted to compare the genotoxic effects of various concentrations of plant oils from Eruca sativa (Brassicaceae, Zingiber officinale (Zingiberaceae and Origanum majorana (Lamiaceae to the conventional organophosphate insecticide (Chlorpyrifos against Rhyzopertha dominica Fabricius. The R. dominica population was reared for several generations without exposure to any insecticide. Wheat grains were sterilized at 55 °C for 6 h in order to eliminate any hidden infestation, treated with serial dilutions of Chlorpyrifos and plant oil extracts, and subsequently fed to R. dominica for 1, 2, 3, 6 and 8 days. The results indicated that the LC50 values of oils from E. sativa, Z. officinale and O. Majorana were 0.14, 0.23 and 0.32%, respectively, after 2 days. Genetic variations in DNA fragments after treatment with LC50 and LC25 concentrations of E. sativa, Z. officinale and O. majorana were detected by RAPD-PCR analysis using five primers. The results exhibited distinct DNA polymorphisms or alterations in DNA bands. These alterations varied depending on the substance being examined. Chlorpyrifos causes the highest level of DNA alterations (based on the appearance and disappearance DNA bands followed by E. sativa, Z. officinale and O. majorana. These results were in direct correlation with the differences in mortality rates between extracts. It could be concluded that the plant oil extracts can be used as one of the integrated pest management tools to control R. dominica in stored products, as they are safer than chemical insecticides.

  12. Insecticidal efficacy of silica nanoparticles against Rhyzopertha dominica F. and Tribolium confusum Jacquelin du Val

    Directory of Open Access Journals (Sweden)

    Ziaee Masumeh

    2016-07-01

    Full Text Available Bioassays were conducted to assess the effects of two silicon dioxide nanoparticles of Aerosil® and Nanosav against adults of Rhyzopertha dominica F. and Tribolium confusum Jacquelin du Val. Silica nanoparticles were applied at the rates of 50, 100, 200 and 300 mg · kg−1 on wheat and peeled barley. The mortality was counted after 1, 2, 3, and 7 days of exposure. Another experiment was carried out to evaluate the effect of food source on the survival of beetles after exposure to silica nanoparticles. Adults were exposed to silica nanoparticles at the rate of 0.2 mg · cm−2 for 1 and 2 days on filter paper inside plastic Petri dishes, respectively. After exposure, the initial mortality was counted and live individuals of both species were held for a week in empty glass vials or vials containing wheat and wheat flour, respectively. Silica nanoparticles have high toxicity on R. dominica and T. confusum adults. Rhyzopertha dominica was more susceptible than T. confusum. However, the mortality of both species increased with increasing concentrations and time exposed to each concentration. At low concentrations, Aerosil® was more effective than Nanosav. Silica nanoparticles were more effective in wheat grains than barley. Results indicated that the initial mortality was so high that the impact of food source on delay mortality was unclear in most cases. Silica nanoparticles were efficient against tested species and can be used effectively in a stored grain integrated pest management program.

  13. Reptile-associated ticks from Dominica and the Bahamas with notes on hyperparasitic erythraeid mites.

    Science.gov (United States)

    Durden, Lance A; Knapp, Charles R; Beati, Lorenza; Dold, Stephanie

    2015-02-01

    Ticks were collected or recorded from 522 individual reptiles on Dominica and from 658 reptiles from the Bahamas. Two species of ticks were collected on Dominica: Amblyomma antillorum and Amblyomma rotundatum. Similarly, 2 species were collected in the Bahamas: Amblyomma albopictum and Amblyomma torrei. On Dominica, A. antillorum was recorded from 517 Lesser Antillean iguanas (Iguana delicatissima), 2 boa constrictors (Boa nebulosa), 1 Antilles snake (Alsophis sibonius), and 1 Dominican ground lizard (Ameiva fuscata), whereas A. rotundatum was recorded from 1 Lesser Antillean skink (Mabuya mabouya). In the Bahamas, A. albopictum was recorded from 131 Andros iguanas (Cyclura cychlura cychlura), 271 Exuma Island iguanas (Cyclura cychlura figginsi), and 1 Andros curlytail lizard (Leiocephalus carinatus coryi), whereas A. torrei was recorded from 255 Exuma Island iguanas. In the Bahamas, A. albopictum parasitized iguanas on Andros Island and the central Exuma Islands, and A. torrei parasitized iguanas in the southern Exumas. An exception to this trend was that A. torrei was collected from iguanas on Pasture Cay in the central Exumas, an anomaly that is explained by the fact that iguanas (with attached ticks) on Pasture Cay were introduced by humans in the past from islands further south. External hyperparasitic larval erythraeid mites ( Leptus sp.) were recorded from A. torrei in the Bahamas.

  14. Andesite Petrogenesis in Nevado de Toluca Stratovolcano, Central Mexico

    Science.gov (United States)

    Gomez-Tuena, A.; Capra, L.; Cai, Y.; Goldstein, S. L.

    2007-05-01

    A popular model for andesite petrogenesis in continental arcs involves a hydrous parental basalt that fractionates and probably assimilates continental crust during ascent. Nevertheless, andesites erupted from polygenetic volcanoes in the Trans-Mexican Volcanic Belt are not entirely consistent with this scenario because: (1) they display a shift to higher SiO2 contents at similar Mg# than true basalts, (2) they trend to lower HREE and HFSE contents with increasing SiO2, and (3) they often show correlated isotopic compositions with proxies for slab inputs but not with fractionation indexes. Young andesites from Toluca stratovolcano (1-0.042 Ma) also display modest adakite-like features (Sr/YToluca rock-suite revealed that some other andesites (2.6-1 Ma) also exhibit very strong negative Ce (Ce/Ce~0.25) anomalies, fractionated HREE patterns (Gd/Yb~4.2), as well as low Zr/Sm (~12.6), and Sr/Y (~12) ratios. These features are not easily explained by low or even high pressure differentiation from a common primitive magma, unless enormous quantities of fractionating accessory minerals are taken into account. And yet these geochemical signals are almost identical to those observed in the pelagic sedimentary horizon of the subducted Cocos plate sampled at DSDP site 487, and thus provide strong evidence for slab-derived sediment contributions to the petrogenesis of Toluca andesites. Since sediment transfer to the Toluca source must have occurred in the form of a silicate melt, the new evidence brings further support to the slab melting hypothesis in the Mexican subduction zone. Interestingly, Ce/Pb ratios of the Toluca rocks display a linear positive correlation with Pb isotopes, that departs from the pelagic sediment values, and extends to the enriched Pb isotopic compositions of intraplate-type volcanic rocks from the Chichinautzin volcanic field. Thus the Toluca rocks likely represent discrete slab-derived melts coming from different portions of the subducted slab that

  15. DIORAMA Earth Terrain Model

    Energy Technology Data Exchange (ETDEWEB)

    Werley, Kenneth Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-10

    When simulating near-surface nuclear detonations, the terrain of the Earth can have an effect on the observed outputs. The critical parameter is called the “height of burst”. In order to model the effect of terrain on the simulations we have incorporated data from multiple sources to give 9 km resolution data with global coverage.

  16. Terrain correlation suitability

    Science.gov (United States)

    Tang, Wang; McClintock, Robert L.

    1994-07-01

    Terrain-aided navigation (TAN), also referred to as terrain correlation, is a technique that has proven to be highly successful as a navigational aid for autonomous, unmanned guided missiles. Qualitatively speaking, the effectiveness of terrain correlation is a function of signal- to-noise (S/N) ratio. The signal is equivalent to terrain roughness, while the noise is the combination of reference map errors, radar altimeter errors, and INS altitude errors. However, it is not practical to use only a single parameter, such as S/N, to define the suitability of terrain correlation. This paper discusses the shortcomings of the conventional single-parameter approach to the terrain contour matching algorithm (TERCOM) used in cruise missile guidance systems scene selection. A more comprehensive technique is then presented that analyzes the terrain correlation suitability based on a Monte Carlo simulation technique. A figure-of-merit (FOM) for terrain correlation suitability, computed from sample statistics, is introduced and simulation results are provided to illustrate the feasibility of using a multi-parameter FOM technique. The preliminary results indicate that the proposed approach could provide a cost effective enhancement to the TAN-based mission planning process.

  17. Terrain Software Conversion.

    Science.gov (United States)

    1987-06-29

    iv~ 1. Background. In 1979, CASAA (now TRAC-FLVN) contracted BDM Corporation to produce a terrain data base for the Corps Battle Game (predecessor to...vie% and mod-fv terrain Gata used by several of TRAO-FLVN’s war - si-,ulatiors was comnatible only with Tektronix 4027 hardware. TAB-GT was -,e- tc

  18. Eucalyptus dundasii Maiden essential oil, chemical composition and insecticidal values against Rhyzopertha dominica (F. and Oryzaephilus surinamensis (L.

    Directory of Open Access Journals (Sweden)

    Aref Shiva Parsia

    2015-01-01

    Full Text Available The insecticidal effects of Eucalyptus dundasii Maiden essential oil was studied on the adults of the lesser grain borer, Rhyzopertha dominica (F., and the saw-toothed grain beetle, Oryzaephilus surinamensis (L.. Essential oil was obtained by the hydro-distillation method and essential oil composition was analysed by GC-MS. Chemical analysis indicated that 1,8-cineole (54.15%, p-cymene (12.41%, α-thujene (11.37%, and E-caryophyllene (6.7% were major constituents. For R. dominica and O. surinamensis, the LC50 of E. dundasii essential oil was 41.69 and 57.92 μl · l-1 of air, respectively. Increasing the concentration of the essential oil and the exposure time, increased mortality. The durability of fumigant toxicity on O. surinamensis adults was higher than on R. dominica adults and was statistically different. Based on the mean of the repellent indexes and the standard deviation, E. dundasii essence was repellent for both insects at 70, 140, and 280 μl · l-1 of air concentrations. Statistical analysis showed that Relative Growth Rate (RGR in O. surinamensis was higher than in R. dominica, and the Relative Consumption Rate (RCR, the Efficiency of Conversion of Ingested food (ECI, and the Feeding Deterrence Index (FDI in O. surinamensis was lower than in R. dominica. The many diverse bio-effects of E. dundasii essential oil confirmed that it is a good candidate for management of R. dominica and O. surinamensis

  19. Eucalyptus dundasii Maiden essential oil, chemical composition and insecticidal values against Rhyzopertha dominica (F.) and Oryzaephilus surinamensis (L.)

    OpenAIRE

    Aref Shiva Parsia; Valizadegan Oruj; Farashiani Mohammad Ebrahim

    2015-01-01

    The insecticidal effects of Eucalyptus dundasii Maiden essential oil was studied on the adults of the lesser grain borer, Rhyzopertha dominica (F.), and the saw-toothed grain beetle, Oryzaephilus surinamensis (L.). Essential oil was obtained by the hydro-distillation method and essential oil composition was analysed by GC-MS. Chemical analysis indicated that 1,8-cineole (54.15%), p-cymene (12.41%), α-thujene (11.37%), and E-caryophyllene (6.7%) were major constituents. For R. dominica and O. ...

  20. Distribution and size of benthic marine habitats in Dominica, Lesser Antilles

    Directory of Open Access Journals (Sweden)

    Sascha Claus Christoff Steiner

    2010-06-01

    Full Text Available Los ambientes béntico-marinos de Dominica, Antillas Menores, incluyen 1 814.7ha y cerca del 90% de la costa. Este es el primer trabajo sobre el tamaño y distribución de los ambientes costeros sublitorales y sus comunidades epibénticas. Los pastos marinos constituyeron el ambiente más extenso, con 265ha. Los arrecifes coralinos presentaron una cobertura de 72.2ha. Ambos tipos de ambientes se encontraron principalmente en la costa oeste y norte, regiones con la mayor diversidad de ambientes marinos. Las áreas rocosas (911.5ha dominaron las costas este y sur de la isla, y junto con las áreas arenosas (566ha constituyeron el 81% de los ambientes bénticos. La distribución de pastos marinos, que incluyeron cuatro especies nativas y una invasiva, no se pudo corroborar con los pocos informes previos. La cobertura béntica de los arrecifes coralinos de Dominica fue mucho menor que las 7 000ha que se habían reportado previamente. Estas discrepancias ilustran la ventaja de los estudios ambientales basados en trabajo de campo y la compilación sistemática de datos ambientales, especialmente en casos como Dominica donde por lo angosto de la plataforma insular, los ambientes marinos sublitorales quedan muy cerca de los centros urbanos. Se demuestra que técnicas simples pueden ser utilizadas a gran escala alrededor de una isla para realizar inventarios de los recursos marino-costeros, mediante mapas y repositorios públicos de datos para usos futuros, que permiten el desarrollo de medidas de conservación efectivas.

  1. Detection and characterisation of strong resistance to phosphine in Brazilian Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae).

    Science.gov (United States)

    Lorini, Irineu; Collins, Patrick J; Daglish, Gregory J; Nayak, Manoj K; Pavic, Hervoika

    2007-04-01

    As failure to control Rhyzopertha dominica (F.) with phosphine is a common problem in the grain-growing regions of Brazil, a study was undertaken to investigate the frequency, distribution and strength of phosphine resistance in R. dominica in Brazil. Nineteen samples of R. dominica were collected between 1991 and 2003 from central storages where phosphine fumigation had failed to control this species. Insects were cultured without selection until testing in 2005. Each sample was tested for resistance to phosphine on the basis of the response of adults to discriminating concentrations of phosphine (20 and 48 h exposures) and full dose-response assays (48 h exposure). Responses of the Brazilian R. dominica samples were compared with reference susceptible, weak-resistance and strong-resistance strains from Australia in parallel assays. All Brazilian population samples showed resistance to phosphine: five were diagnosed with weak resistance and 14 with strong resistance. Five samples showed levels of resistance similar to the reference strong-resistance strain. A representative highly resistant sample was characterised by exposing mixed-age cultures to a range of constant concentrations of phosphine for various exposure periods. Time to population extinction (TPE) and time to 99.9% suppression of population (LT(99.9)) values of this sample were generally similar to those of the reference strong-resistance strain. For example, at 0.1, 0.5 and 1.0 mg L(-1), LT(99.9) values for BR33 and the reference strong-resistance strain were respectively 21, 6.4 and 3.7 days and 17, 6.2 and 3.8 days. With both strains, doubling phosphine concentrations to 2 mg L(-1) resulted in increased LT(99.9) and TPE. High level and frequency of resistance in all population samples, some of which had been cultured without selection for up to 12 years, suggest little or no fitness deficit associated with phosphine resistance. The present research indicates that widespread phosphine resistance may

  2. TERRAIN, TRAVIS COUNTY, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  3. TERRAIN, Pierce County, WA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, Franklin COUNTY, MS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. TERRAIN, KENDALL COUNTY, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, WORTH COUNTY, IOWA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, BARNSTABLE COUNTY, MASSACHUSETTS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, HOWARD COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, BERKS COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. TERRAIN, MITCHELL COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  11. TERRAIN, MITCHELL COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  12. TERRAIN, Mecklenburg County, NC

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  13. TERRAIN, KITSAP COUNTY, WASHINGTON

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN, FRANKLIN COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  15. TERRAIN, HANCOCK COUNTY, OH

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  16. TERRAIN, MIAMI COUNTY, OH

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN, DELAWARE COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, NOBLES COUNTY, MN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. TERRAIN, PIERCE, COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. TERRAIN, SHERIDAN COUNTY, WY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. TERRAIN, DAWSON COUNTY, NE

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN, Northampton COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that were used to create...

  3. TERRAIN, TULSA COUNTY, OKLAHOMA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, POTTER COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that were used to create...

  5. TERRAIN, CALVERT COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, Bennington County, Vermont

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, LAWRENCE COUNTY, ARKANSAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, WEBER COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, LEON COUNTY, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  10. TERRAIN, Norfolk County, Massachusetts

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  11. TERRAIN, Hampden County, Massachusetts

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  12. TERRAIN, Walthall COUNTY, MS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. TERRAIN, CLALLAM COUNTY, WASHINGTON

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN, CEDAR COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  15. TERRAIN, HARDIN COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  16. TERRAIN, DARKE COUNTY, OH

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN, WRIGHT COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, TROUSDALE COUNTY, TENNESSEE

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. TERRAIN, WAYNE COUNTY, TENNESSEE

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. TERRAIN, CECIL COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. International Civic Engagement: From Development Studies and Service-Learning, to Miami University-Dominica Partnerships

    Directory of Open Access Journals (Sweden)

    Thomas Klak

    2012-04-01

    Full Text Available During the past four years, faculty, students, and staff from Miami University have been cultivating civic engagement relationships with citizens of the Commonwealth of Dominica, in the Eastern Caribbean. For members of the Miami University community, this has been an effort to create opportunities for learning and scholarship through partnerships with people in the Global South who are working for community empowerment, progressive change, and sustainable development. For our Dominican counterparts, benefits include financial inputs, manual labor, relevant research projects, and an outside interest in contributing positively to ameliorating their community challenges. We work to base the Miami University-Dominica relationships on trust, long-term commitment, and mutuality, so that the benefits go back and forth in myriad ways. The result has been a set of relationships across international borders and cultural differences that is more fulfilling for both sides than typical study abroad, research, or ecotourism encounters in the Global South. This paper describes the conceptual underpinnings of this international civic engagement, and recounts three examples of the kinds of community groups and activities that the partnerships involve. We also note where the project has encountered constraints and limitations, and our next steps in the effort. We hope this example can serve as a template and motivation for other university groups to commit to cultivating civic engagement relationships with people and communities in the Global South. KEYWORDScivic engagement; community engagement; community partnerships; sustainability

  2. DAÑOS EN GERMOPLASMA DE CEBADA (Hordeum vulgare Lin. PRODUCIDOS POR Rhyzoperta dominica FABRICIUS

    Directory of Open Access Journals (Sweden)

    Regla M. Cárdenas

    2009-01-01

    Full Text Available Los daños cuantitativos producidos por plagas de almacén revisten vital importancia cuando se trata de semillas con destino a la investigación, pues generalmente las cantidades son muy pequeñas. El estudio se desarrolló con el objetivo de conocer las pérdidas de este tipo, producidas por Rhyzoperta dominica F. en semillas de 96 líneas de cebada procedentes de Siria y conservadas a la temperatura de 15 ± 2°C durante seis meses; para ello, se tuvo en cuenta la reducción producida en el peso (g, se determinó el peso de mil granos (PMG, se estimó el número de insectos adultos en mil granos (NAMG y se calculó, además, el índice de ataque (IA. Los resultados mostraron que 12 líneas presentaron daños producidos por R. dominica, con una pérdida promedio de 18 % en el peso en gramos; las líneas en estudio mostraron un bajo PMG (32.38 g, mientras el NAMG estimado fue de 31.25 y el IA de 3.17 %.

  3. Origin of High-Alumina Basalt, Andesite, and Dacite Magmas.

    Science.gov (United States)

    Hamilton, W

    1964-10-30

    The typical volcanic rocks of most island arcs and eugeosynclines, and of some continental environments, are basalt, andesite, and dacite, of high alumina content. The high-alumina basalt differs from tholeiitic basalt primarily in having a greater content of the components of calcic plagioclase. Laboratory data indicate that in the upper mantle, below the level at which the basaltic component of mantle rock is transformed by pressure to eclogite or pyroxenite, the entire basaltic portion probably is melted within a narrow temperature range, but that above the level of that transformation plagioclase is melted selectively before pyroxene over a wide temperature range. The broad spectrum of high-alumina magmas may represent widely varying degrees of partial melting above the transformation level, whereas narrow-spectrum tholeiite magma may represent more complete melting beneath it.

  4. Children, Learning and Chronic Natural Disasters: How Does the Government of Dominica Address Education during Low-Intensity Hurricanes?

    Science.gov (United States)

    Serrant, Ted Donaldson

    2013-01-01

    By the time today's Grade K students graduate high school in the Commonwealth of Dominica, they will have experienced five major and many low-intensity hurricanes (LIH). Between August and November each year, each hurricane, major or low-intensity, represents a major threat to their safety and schooling. This mixed-method case study investigated…

  5. A Method for Measuring Fishing Effort by Small-Scale Fish Aggregating Device (FAD) Fishers from the Commonwealth of Dominica

    Science.gov (United States)

    Alvard, Michael; McGaffey, Ethan; Carlson, David

    2015-01-01

    We used global positioning system (GPS) technology and tracking analysis to measure fishing effort by marine, small-scale, fish aggregating device (FAD) fishers of the Commonwealth of Dominica. FADs are human-made structures designed to float on the surface of the water and attract fish. They are also prone to common pool resource problems. To…

  6. Contact and fumigant toxicities of calamusenone isolated from Acorus gramineus rhizome against adults of Sitophilus zeamais and Rhizopertha dominica

    Institute of Scientific and Technical Information of China (English)

    Yan-Zhang Huang; Hong-Xia Hua; Shi-Guang Li; Chang-Ju Yang

    2011-01-01

    Calamusenone [3,8-dimethyl-5-(l-methylethylidene)- 1,2,3,4,5,6,7,8-octa-hydroazulene-6-one, C15H220] from Acorus gramineus Soland rhizome was tested in the laboratory for its insecticidal activities against adults of Sitophilus zeamais Motsch. and Rhizopertha dominica (Fab.), using dry film contact and fumigation methods. Responses varied with insect species, dosage and exposure time. In the dry film contact experiment, the highest insecticidal effects of calamusenone against S. zeamais and R. dominica adults were produced at 170.32 μg/cm2 after treatment for 72 h, with 96.2% and 98.7% mortalities, respectively. The median lethal concentration (LC50) (72 h) values of calamusenone against S. zeamais and R. dominica adults were 67.00 μg/cm2 and 77.30 μg/cm2, respectively. As a potential fumigant, calamusenone showed moderate insecticidal effect on the adults of S. zeamais and R. dominica in fumigation experiment, with their LC50 (120 h) values of 125.7μzL/L and 93.64μL/L respectively. Calamusenone isolated from A. gramineus rhizome showed promise as a novel pesticide candidate for stored-product pest control.

  7. Control of Rhyzopertha dominica (F.) in stored rough rice through a combination of diatomaceous earth and varietal resistance

    Science.gov (United States)

    Adults of Rhyzopertha dominica (F.), the lesser grain borer, were exposed on four varieties of rough rice each with low (Jupiter, Bengal, Wells, Progue) and high (Rico, M-205, Akita, and Cocodrie) Dobie indices of susceptibility, and treated with varying rates of the commercial diatomaceous earth (D...

  8. Magma heating by decompression-driven crystallization beneath andesite volcanoes.

    Science.gov (United States)

    Blundy, Jon; Cashman, Kathy; Humphreys, Madeleine

    2006-09-01

    Explosive volcanic eruptions are driven by exsolution of H2O-rich vapour from silicic magma. Eruption dynamics involve a complex interplay between nucleation and growth of vapour bubbles and crystallization, generating highly nonlinear variation in the physical properties of magma as it ascends beneath a volcano. This makes explosive volcanism difficult to model and, ultimately, to predict. A key unknown is the temperature variation in magma rising through the sub-volcanic system, as it loses gas and crystallizes en route. Thermodynamic modelling of magma that degasses, but does not crystallize, indicates that both cooling and heating are possible. Hitherto it has not been possible to evaluate such alternatives because of the difficulty of tracking temperature variations in moving magma several kilometres below the surface. Here we extend recent work on glassy melt inclusions trapped in plagioclase crystals to develop a method for tracking pressure-temperature-crystallinity paths in magma beneath two active andesite volcanoes. We use dissolved H2O in melt inclusions to constrain the pressure of H2O at the time an inclusion became sealed, incompatible trace element concentrations to calculate the corresponding magma crystallinity and plagioclase-melt geothermometry to determine the temperature. These data are allied to ilmenite-magnetite geothermometry to show that the temperature of ascending magma increases by up to 100 degrees C, owing to the release of latent heat of crystallization. This heating can account for several common textural features of andesitic magmas, which might otherwise be erroneously attributed to pre-eruptive magma mixing.

  9. Viscosity measurements of crystallizing andesite from Tungurahua volcano (Ecuador)

    Science.gov (United States)

    Cimarelli, Corrado; deBiasi, Lea; Hanson, Jonathan B.; Lavallée, Yan; Arzilli, Fabio; Dingwell, Donald B.

    2015-01-01

    Abstract Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt‐sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but rather left in the sample during quenching thus preserving an undisturbed textural configuration of the crystals. The inspection of products quenched during the crystallization process reveals evidence for heterogeneous crystal nucleation at the spindle and near the crucible wall, as well as crystal alignment in the flow field. At the end of the crystallization, defined when viscosity is constant, plagioclase is homogeneously distributed throughout the crucible (with the single exception of experiment performed at the lowest temperature). In this experiments, the crystallization kinetics appear to be strongly affected by the stirring conditions of the viscosity determinations. A TTT (Time‐Temperature‐Transformation) diagram illustrating the crystallization “nose” for this andesite under stirring conditions and at ambient pressure has been constructed. We further note that at a given crystal content and distribution, the high aspect ratio of the acicular plagioclase yields a shear‐thinning rheology at crystal contents as low as 13 vol %, and that the relative viscosity is higher than predicted from existing viscosity models. These viscosity experiments hold the potential for delivering insights into the relative influences of the cooling path, undercooling, and deformation on crystallization kinetics and resultant crystal morphologies, as well as their impact on magmatic viscosity. PMID:27656114

  10. Viscosity measurements of crystallizing andesite from Tungurahua volcano (Ecuador).

    Science.gov (United States)

    Chevrel, Magdalena Oryaëlle; Cimarelli, Corrado; deBiasi, Lea; Hanson, Jonathan B; Lavallée, Yan; Arzilli, Fabio; Dingwell, Donald B

    2015-03-01

    Viscosity has been determined during isothermal crystallization of an andesite from Tungurahua volcano (Ecuador). Viscosity was continuously recorded using the concentric cylinder method and employing a Pt-sheathed alumina spindle at 1 bar and from 1400°C to subliquidus temperatures to track rheological changes during crystallization. The disposable spindle was not extracted from the sample but rather left in the sample during quenching thus preserving an undisturbed textural configuration of the crystals. The inspection of products quenched during the crystallization process reveals evidence for heterogeneous crystal nucleation at the spindle and near the crucible wall, as well as crystal alignment in the flow field. At the end of the crystallization, defined when viscosity is constant, plagioclase is homogeneously distributed throughout the crucible (with the single exception of experiment performed at the lowest temperature). In this experiments, the crystallization kinetics appear to be strongly affected by the stirring conditions of the viscosity determinations. A TTT (Time-Temperature-Transformation) diagram illustrating the crystallization "nose" for this andesite under stirring conditions and at ambient pressure has been constructed. We further note that at a given crystal content and distribution, the high aspect ratio of the acicular plagioclase yields a shear-thinning rheology at crystal contents as low as 13 vol %, and that the relative viscosity is higher than predicted from existing viscosity models. These viscosity experiments hold the potential for delivering insights into the relative influences of the cooling path, undercooling, and deformation on crystallization kinetics and resultant crystal morphologies, as well as their impact on magmatic viscosity.

  11. Studi Potensi Sumberdaya Andesit Menggunakan Metode Geolistrik Di Daerah Kokap, Kabupaten Kulonprogo, Daerah Istimewa Yogyakarta

    Directory of Open Access Journals (Sweden)

    Eko Bayu Purwasatriya

    2013-06-01

    Full Text Available The study of andesite resources was carried out in Hargowilis village, Kokap sub-district, Kulonprogo regency, Daerah Istimewa Yogyakarta province using geoelectrical data with Schlumberger configuration, as much as 14 point which is spreading on 8 hectares area. Based on regional geological map of Yogyakarta area, study area include on intrusive rock lithology’s unit compose of hipersten andesite to augite-hornblende andesite and trachiandesite. Geoelectrical method is one of geophysical method that used to observed geological condition in subsurface based on rock’s electrical properties. Andesite is one type of igneous rock which have contrast electrical properties with its surrounding rock, generally sedimentary rocks, makes it suitable for geoelectrical method to identify the presence of andesite in subsurface and also estimate its thickness to calculate the resources. Geoelectrical configuration used is 1D Schlumberger configuration where this method have advantage more accurate to calculate the thickness of rock layer especially in shallow area. The result of geoelectrical survey showing that it consist 2 layer of andesite, there are shallow layer and deep layer. This result indicate that the igneous rock in study area not only intrusion type, but also lava flow type. Resources potential of andesite both shallow and deep layer are 5,072,354 tons and resources potential of shallow andesite only is 3,162,566 tons.

  12. Control of Rhyzopertha dominica in stored rough rice through a combination of diatomaceous earth and varietal resistance

    Institute of Scientific and Technical Information of China (English)

    Yaowaluk Chanbang; Frank H Arthur; Gerald E. Wilde; James E. Throne

    2008-01-01

    Adults of Rhyzopertha dominica(F.),the lesser grain borer, were exposed on four varieties of rough rice with Dobie indices of susceptibility of 1.1 to 1.1 (low), and four varieties with Dobie indices of susceptibility of 3.4 to 3.8 (high). The varieties with low and high Dobie indices were classified as resistant and susceptible, respectively, to R. dominica.The purpose of the study was to evaluate control of R. dominica through the use of diatomaceous earth (DE) in combination with rice varieties that were either susceptible or resistant to R. dominica. The rice was treated with varying rates of the commercial DE lnsecto(R), up to a maximum of 1000 mg DE/kg of rice. Adult mortality at each application rate of DE was generally greater on three of four resistant varieties compared to three of four susceptible varieties. Progeny production from the parental generation exposed on the rice was also greater in 3 of the 4 resistant varieties compared to 3 of the 4 susceptible varieties at DE rates of 500 mg/kg or more. Progeny production in rice treated with a maximum rate of 1000 mg/kg DE ranged from 7-44 adults on the resistant varieties compared to 75-155adults on the susceptible varieties. At DE rates of 500, 750, and 1000 mg/kg, the percentage of insect-damaged kernels (IDK) was also greater in 3/4 resistant varieties than in the susceptible varieties. Results show combining the use of DE with varietal resistance of rough rice to R. dominica could be used to limit populations of this insect in stored rice and help prevent economic damage.

  13. Influence of growing location and cultivar on Rhyzopertha dominica (Coleoptera: Bostrichidae) and Sitophilus oryzae (Coleoptera: Curculionidae) infestation of rough rice

    Institute of Scientific and Technical Information of China (English)

    FRANK H. ARTHUR; RUSTY C. BAUTISTA; TERRENCE J. SIEBENMORGEN

    2007-01-01

    Long-grain rice cultivars Cocodrie, Wells, and XP 723 grown in three locations (Hazen, MO; Essex and Newport, AR, USA), and medium-grain rice cultivars Bengal and XP 713 grown in two locations (Jonesboro and Lodge Corner, AR, USA), were harvested and assayed for susceptibility to Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), the lesser grain borer, and Sitophilus oryzae (L.) (Coleoptera: Curculionidae), the rice weevil, on rice held at 27℃ 57% and 75% relative humidity (RH).Separate samples from the same harvest lots were also analyzed for the physical characteristics of brown rice yield, percentage whole kernels and kernel thickness. Progeny production and feeding damage of R. dominica were significantly different among long-grain cultivars within two of the three locations (P < 0.05), but not for location or RH (P ≥ 0.05), while progeny production of S. oryzae was different among cultivars, location, and RH (P < 0.05). On medium-grain rice, both cultivar and location were significant for progeny production of R. dominica, but not RH, while cultivar and RH were significant for progeny production of S. oryzae, but not location. On both rice types, feeding damage of R. dominica followed the same trends and was always strongly positively correlated with progeny production (P < 0.05), but for S. oryzae there were several instances in which progeny production was not correlated with feeding damage (P ≥ 0.05). Physical characteristics of both rice types were statistically significant (P < 0.01) but actual numerical differences were extremely small, and were generally not correlated with progeny production of either species. Results indicate that the location in which a particular rice cultivar is grown, along with its characteristics, could affect susceptibility of the rice to R. dominica and S. oryzae.

  14. DspaceOgreTerrain 3D Terrain Visualization Tool

    Science.gov (United States)

    Myint, Steven; Jain, Abhinandan; Pomerantz, Marc I.

    2012-01-01

    DspaceOgreTerrain is an extension to the DspaceOgre 3D visualization tool that supports real-time visualization of various terrain types, including digital elevation maps, planets, and meshes. DspaceOgreTerrain supports creating 3D representations of terrains and placing them in a scene graph. The 3D representations allow for a continuous level of detail, GPU-based rendering, and overlaying graphics like wheel tracks and shadows. It supports reading data from the SimScape terrain- modeling library. DspaceOgreTerrain solves the problem of displaying the results of simulations that involve very large terrains. In the past, it has been used to visualize simulations of vehicle traverses on Lunar and Martian terrains. These terrains were made up of billions of vertices and would not have been renderable in real-time without using a continuous level of detail rendering technique.

  15. Submarine Salt Karst Terrains

    Directory of Open Access Journals (Sweden)

    Nico Augustin

    2016-06-01

    Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many

  16. Gas and water geochemistry of geothermal systems in Dominica, Lesser Antilles island arc

    Science.gov (United States)

    Joseph, Erouscilla P.; Fournier, Nicolas; Lindsay, Jan M.; Fischer, Tobias P.

    2011-09-01

    Four of the nine potentially active volcanoes on the island of Dominica in the Lesser Antilles volcanic island arc have associated active volcanic-hydrothermal systems. Between 2000 and 2006 the gas and thermal waters from these systems were investigated to geochemically characterise the fluids, gain insight into the temperature and equilibrium state of the underlying reservoirs, and evaluate the feasibility of monitoring geothermal features as a volcano surveillance tool in Dominica. The geothermal gases are typical of those found in arc-type settings, with N 2 excess and low amounts of He and Ar. The dry gas is dominated by CO 2 (ranging from 492 to 993 mmol/mol), and has a hydrothermal signature with hydrogen sulphide as the main sulphurous gas. The waters are predominantly acid-sulphate (SO 4 = 100-4200 mg/L, pH ≤ 4), and likely formed as a result of dilution of acidic gases in near surface oxygenated groundwater. Enrichment in both δ 18O and δD with respect to the global meteoric water line (GMWL) confirms that the waters are of primarily meteoric origin, but have been affected by evaporation processes. Quartz geothermometers gave equilibrium temperatures of 83 °C-203 °C. These temperatures contrast with the higher equilibrium temperature ranges (170 °C-350 °C) obtained for the gases using the H 2/Ar*-CH 4/CO 2 gas ratios plot, suggesting that the quartz geothermometers are affected by non-attainment of equilibrium. This may be a result of precipitation of the dissolved silica and/or dilution by relatively cold shallow aquifers of the thermal fluids. Generally, no significant variations in fluid gas chemistry of the hydrothermal systems were observed during the study period, and we propose that there were no changes in the state of volcanic activity in this period. One exception to this occurred in a feature known as the Boiling Lake, which underwent a month-long period of significant compositional, temperature and water level fluctuations ascribed to

  17. Melting the hydrous, subarc mantle: the origin of primitive andesites

    Science.gov (United States)

    Mitchell, Alexandra L.; Grove, Timothy L.

    2015-08-01

    This experimental study is the first comprehensive investigation of the melting behavior of an olivine + orthopyroxene ± spinel—bearing fertile mantle (FM) composition as a function of variable pressure and water content. The fertile composition was enriched with a metasomatic slab component of ≤0.5 % alkalis and investigated from 1135 to 1470 °C at 1.0-2.0 GPa. A depleted lherzolite with 0.4 % alkali addition was also studied from 1225 to 1240 °C at 1.2 GPa. Melts of both compositions were water-undersaturated: fertile lherzolite melts contained 0-6.4 wt% H2O, and depleted lherzolite melts contained ~2.5 wt% H2O. H2O contents of experimental glasses are measured using electron microprobe, secondary ion mass spectrometry, and synchrotron-source reflection Fourier transform infrared spectroscopy, a novel technique for analyzing H2O in petrologic experiments. Using this new dataset in conjunction with results from previous hydrous experimental studies, a thermobarometer and a hygrometer-thermometer are presented to determine the conditions under which primitive lavas were last in equilibration with the mantle. These predictive models are functions of H2O content and pressure, respectively. A predictive melting model is also presented that calculates melt compositions in equilibrium with an olivine + orthopyroxene ± spinel residual assemblage (harzburgite). This model quantitatively predicts the following influences of H2O on mantle lherzolite melting: (1) As melting pressure increases, melt compositions become more olivine-normative, (2) as melting extent increases, melt compositions become depleted in the normative plagioclase component, and (3) as melt H2O content increases, melts become more quartz-normative. Natural high-Mg# [molar Mg/(Mg + Fe2+)], high-MgO basaltic andesite and andesite lavas—or primitive andesites (PAs)—contain high SiO2 contents at mantle-equilibrated Mg#s. Their compositional characteristics cannot be readily explained by melting

  18. Composition-volume changes during hydrothermal alteration of andesite at Buttercup Hill, Noranda District, Quebec

    Science.gov (United States)

    Lesher, C. M.; Gibson, H. L.; Campbell, I. H.

    1986-12-01

    Hydrothermally altered andesites in the upper member of the Amulet formation at Buttercup Hill, Noranda, Quebec represent part of the aquifer and cap of a self-sealing geothermal system that focussed the discharge of hydrothermal fluids during the formation of massive Cu-Zn sulfide deposits. Five alteration facies are recognized pervasive greenschist faciés regional metamorphism (least-altered andesite) epidotization-silicification albitization-silicification chloritization sericitization-silicification. Alteration is localized on permeable zones such as amygdules, fractures, flow tops, discordant breccia dikes, and conformable breccia horizons. Epidotized-silicified andesite is enriched in Ca-Sr-Eu and depleted in Mg and first transition series metals (FTSM) relative to least-altered andesite. Albitized-silicified andesite is significantly enriched in Na and depleted in most FTSM relative to least-altered andesite. The abundances and inter-element ratios of the rare-earth elements (REE) and most high field-strength elements (HFS: Y, Zr, Th, U, Hf, Ta) are similar in least-altered, epidotized-silicified and albitized-silicified andesites. The most silicified andesites are strongly enriched in Na-Si, strongly depleted in Mg and divalent FTSM and slightly but systematically depleted in REE and most HFS elements. Serialized andesites were previously silicified; they are very strongly enriched in K-Rb-Cs-Ba, very strongly depleted in Na-Ca-Sr-Eu and slightly depleted in light REE relative to silicified andesite. Chloritized andesitic rocks exhibit heavy REE and HFS element ratios similar to those of leastaltered andesite, but are relatively strongly enriched in Mg and divalent FTSM, strongly depleted in Si and large ion lithophile (LIL) elements and slightly depleted in light REE. The coupled behavior of the heavy REE and most HFS elements during epidotization, albitization, silicification, chloritization and serialization suggests that they were inert during

  19. Controle de Rhyzopertha dominica pela atmosfera controlada com CO2, em trigo Control of Rhyzopertha dominica using a controlled atmosphere with CO2, in wheat

    Directory of Open Access Journals (Sweden)

    Rogério Amaro Gonçalves

    2000-01-01

    Full Text Available A utilização de gases inertes como fumigantes no controle de pragas é uma alternativa ao uso de fosfina. O objetivo deste trabalho foi avaliar a eficiência de uma atmosfera com CO2 no controle de Rhyzoperta dominica (Fabr. (Coleoptera: Bostrichidae em grãos de trigo armazenado. O trabalho constou de cinco concentrações de CO2 (0, 30 , 40, 50 e 60%, completadas com N2, três períodos de exposição (5, 10, 15 dias, três populações de R. dominica (Fabr. (Coleoptera: Bostrichidae (Campo Mourão, PR, Sete Lagoas, MG e Santa Rosa, RS e sete fases de desenvolvimento do inseto (ovo, larva de 1º, 2º, 3º e 4º ínstar, pupa e adulto com três repetições. As diferentes fases da R. dominica foram acondicionadas em tecido organza e levadas para câmaras de expurgo de 200 litros com 75% deste volume repletos de grãos. As câmaras foram vedadas com borracha de silicone para garantir a hermeticidade. Após a vedação das câmaras injetavam-se os gases contendo diferentes teores de CO2. Os resultados mostraram que todos os teores de CO2 causaram 100% de mortalidade de adultos das três populações nos três períodos de exposição utilizados. Em pupas a mortalidade atingiu 100% no teor de 60% de CO2 para as três populações no período de 15 dias de exposição; porém, todos os teores de CO2 utilizados no período de 15 dias de exposição causaram 100% de mortalidade das pupas da população de Santa Rosa. Para o adequado controle de larvas de diferentes ínstares são necessários teores de CO2 iguais ou acima de 50%. Nos períodos de 10 e 15 dias de exposição, todos os teores de CO2 causaram 100% de mortalidade dos ovos das três populações avaliadas.Controlled atmosphere with inert gases offers an alternative to phosphine use to control stored grain pests. The objective of this research was to test a controlled atmosphere with CO2 to control Rhyzoperta dominica, (Fabr. (Coleoptera: Bostrichidae, an important pest of stored wheat

  20. Sakhalin Island terrain intelligence

    Science.gov (United States)

    ,

    1943-01-01

    This folio of maps and explanatory tables outlines the principal terrain features of Sakhalin Island. Each map and table is devoted to a specialized set of problems; together they cover the subjects of terrain appreciation, climate, rivers, water supply, construction materials, suitability for roads, suitability for airfields, fuels and other mineral resources, and geology. In most cases, the map of the island is divided into two parts: N. of latitude 50° N., Russian Sakhalin, and south of latitude 50° N., Japanese Sakhalin or Karafuto. These maps and data were compiled by the United States Geological Survey during the period from March to September, 1943.

  1. Distribution and size of benthic marine habitats in Dominica, Lesser Antilles

    Directory of Open Access Journals (Sweden)

    Sascha Claus Christoff Steiner

    2010-06-01

    Full Text Available Los ambientes béntico-marinos de Dominica, Antillas Menores, incluyen 1 814.7ha y cerca del 90% de la costa. Este es el primer trabajo sobre el tamaño y distribución de los ambientes costeros sublitorales y sus comunidades epibénticas. Los pastos marinos constituyeron el ambiente más extenso, con 265ha. Los arrecifes coralinos presentaron una cobertura de 72.2ha. Ambos tipos de ambientes se encontraron principalmente en la costa oeste y norte, regiones con la mayor diversidad de ambientes marinos. Las áreas rocosas (911.5ha dominaron las costas este y sur de la isla, y junto con las áreas arenosas (566ha constituyeron el 81% de los ambientes bénticos. La distribución de pastos marinos, que incluyeron cuatro especies nativas y una invasiva, no se pudo corroborar con los pocos informes previos. La cobertura béntica de los arrecifes coralinos de Dominica fue mucho menor que las 7 000ha que se habían reportado previamente. Estas discrepancias ilustran la ventaja de los estudios ambientales basados en trabajo de campo y la compilación sistemática de datos ambientales, especialmente en casos como Dominica donde por lo angosto de la plataforma insular, los ambientes marinos sublitorales quedan muy cerca de los centros urbanos. Se demuestra que técnicas simples pueden ser utilizadas a gran escala alrededor de una isla para realizar inventarios de los recursos marino-costeros, mediante mapas y repositorios públicos de datos para usos futuros, que permiten el desarrollo de medidas de conservación efectivas.Surveys of benthic marine habitats encompassing 1 814.7ha and lining 90% of Dominica’s shoreline were carried out to build the first composite picture of the distribution and size of the island’s near-shore sublittoral habitats, and the epibenthic communities they harbor. Field survey sites covered areas ranging from 1 425 to 29.6ha, lining the shore in bands ranging between 50 and 250m in width, in waters no deeper than 30m. Thus a

  2. Insecticidal and insect-repellent activities of essential oils from Verbenaceae and Anacardiaceae against Rhizopertha dominica.

    Science.gov (United States)

    Benzi, Verónica S; Murrayb, Ana P; Ferrero, Adriana A

    2009-09-01

    Essential oils extracted from leaves of Aloysia polystachya and A. citriodora (Verbenaceae) and from leaves and fruits of Schinus molle var. areira (Anacardiaceae) were tested for their repellent and toxic activities against adults of Rhizopertha dominica (Coleoptera: Bostrichidae). Topical application and filter paper assays were employed for contact toxicity studies; filter paper impregnation was also used for fumigant and repellent assays. In topical tests A. polystachya was as effective as S. molle leaves. In the case of repellent assays, A. citriodora was the most effective oil based on the class scale. A. polystachya was the most toxic plant on contact toxicity by filter paper assay (LC50 26.6 mg/cm2). Fumigant toxicity was only evaluated with fruits and leaves of S. molle, and no significant differences were found between them. Published data are included to compare the fumigant toxicity of S. molle with that of A. citridora and A. polystachya.

  3. Weathering Rinds and Soil Development on Basaltic Andesite, Guadeloupe

    Science.gov (United States)

    Sak, P. B.; Murphy, M.; Ma, L.; Engel, J.; Pereyra, Y.; Gaillardet, J.; Brantley, S. L.

    2014-12-01

    An oriented clast of basaltic andesite collected from the B horizon of a soil developed in a late Quaternary volcanoclastic debris flow on the eastern, windward side of Basse Terre Island, Guadeloupe exhibits weathering patterns like that observed in many clasts from tropical settings. The sample consists of unweathered core material overlain by a ~19 mm thick weathering rind and a narrow ≤ 2mm thick indurated horizon separating the outer portion of the rind from the overlying >10mm of soil matrix material. Elemental variations are constrained by a seven point bulk ICP-AES vertical transect extending from the core, across the rind and ~15 mm into the overlying soil matix and six parallel electron microprobe transections. The porous-hydrated fraction increases from the core to the rind to the surrounding soil from 7±4% to 45±18% to 60±15%, respectively. Like the well-studied clast from the nearby Bras David watershed (Sak et al., 2010) the isovolumetric transformation from core to rind material is marked by a narrow (Ba>K≈Mn>Mg>Si>Al≈P>Fe»Ti, consistent with the relative reactivity of phases in the clast from plagioclasepyroxeneglass>apatite>ilmenite. Unlike previously studied clasts, the preservation of the rind-soil interface permits characterization of weathering reactions between the weathering clast and surrounding soil matrix. The abrupt (weathering rind suggests that weathering processes active within clasts are distinct from surrounding soil formation processes.

  4. Combining Geological and Geophysical Data in Volcanic Hazard Estimation for Dominica, Lesser Antilles

    Science.gov (United States)

    George, O.; Latchman, J. L.; Connor, C.; Malservisi, R.; Connor, L.

    2014-12-01

    Risk posed by volcanic eruptions are generally quantified in a few ways; in the short term geophysical data such as seismic activity or ground deformation are used to assess the state of volcanic unrest while statistical approaches such as spatial density estimates are used for long term hazard assessment. Spatial density estimates have been used in a number of monogenetic volcanic fields for hazard map generation and utilize the age, location and volumes of previous eruptions to calculate the probability of a new event occurring at a given location within this field. In a previously unpublished study, spatial density estimates of the Lesser Antilles volcanic arc showed the island of Dominica to have the highest likelihood of future vent formation. In this current study, this technique was used in combination with relocated seismic events occurring beneath Dominica within the last ~ 20 years as well as InSAR images of ground deformation to generate a hazard map which not only takes into consideration the past events but also the current state of unrest. Here, geophysical data serve as a weighting factor in the estimates with those centers showing more vigorous activity receiving stronger favorability in the assessment for future activity. In addition to this weighting, the bandwidth utilized in the 2D-radially symmetric kernel density function was optimized using the SAMSE method so as to find the value which best minimizes the error in the estimate. The end results of this study are dynamic volcanic hazards maps which will be readily updatable as changes in volcanic unrest occurs within the system.

  5. Phreatic activity on Dominica (Lesser Antilles) - constraints from field investigations and experimental volcanology

    Science.gov (United States)

    Mayer, K.; Scheu, B.; Rott, S.; Dingwell, D. B.; Gilg, H. A.

    2015-12-01

    Dominica has one of the highest concentrations of potentially active volcanoes worldwide. In addition to this activity, abundant geothermal manifestations are observed at the surface, especially in the southern part of the Island. The Boiling Lake - Valley of Desolation area is one of the most vigorous ones, hosting hot springs, mud pools, fumaroles, and steam vents. Intense alteration and many, predominantly phreatic explosive features, of varying scales characterize the whole area. The most prominent manifestation of such a phreatic eruption is the Boiling Lake, a high temperature volcanic crater lake and popular tourist attraction. Thus phreatic activity is one of the main volcanic hazards on the Island, to date largely unpredictable in time and magnitude. The conditions causing these eruptions, as well as their trigger mechanisms and magnitude need to be better understood. Field mapping, together with the determination of in situ physical (density, humidity, permeability) and mechanical (strength, stiffness) properties yield the characterization of 3 main active areas with high probabilities for phreatic events. Rapid decompression experiments on samples from these areas gave insights into the fragmentation and ejection behavior. These experiments were flanked by chemical analyses and laboratory characterization (porosity, granulometry). The results show that hydrothermal alteration likely plays a crucial role in determining the probability of explosive events. High temperature acidic fluids, which lead to an intense alteration of the host rock's mineralogy, change the rock properties favoring the formation of a low permeability layer above the vent and increasing the likelihood of the site experiencing a steam-blast eruption. The contribution of these results to constraining the conditions for and the dynamics involved in phreatic eruptions provides valuable input to hazard assessment of these frequently visited sites on Dominica and similar hydrothermally

  6. Flow on noisy terrains

    DEFF Research Database (Denmark)

    Tsirogiannis, Konstantinos; Haverkort, Herman

    2011-01-01

    Computing watersheds on triangulated terrain models in a robust manner is a difficult task as it is sensitive to noise that appears in the elevation values of the input. This is amplified by the existence of many very small watersheds (corresponding to spurious minima) that obscure the overall hy...... to use a robust flow model together with exact arithmetic....

  7. Navigating Hypermasculine Terrains

    DEFF Research Database (Denmark)

    Henriksen, Ann-Karina Eske

    2015-01-01

    The study addresses how young women navigate urban terrains that are characterized by high levels of interpersonal aggression and crime. It is argued that young women apply a range of gendered tactics to establish safety and social mastery, and that these are framed by the limits and possibilitie...

  8. Good terrain geometry, cheap!

    Energy Technology Data Exchange (ETDEWEB)

    Duchaineau, M. [Los Alamos National Lab., NM (United States)]|[Lawrence Livermore National Lab., CA (United States); Wolinsky, M.; Sigeti, D.E. [Los Alamos National Lab., NM (United States)] [and others

    1997-04-01

    Real-time terrain rendering for interactive visualization remains a demanding task. We present a novel algorithm with several advantages over previous methods: our method is unusually stingy with polygons yet achieves real-time performance and is scalable to arbitrary regions and resolutions. The method provides a continuous terrain mesh of specified triangle count having provably minimum error in restricted but reasonably general classes of permissible meshes and error metrics. Our method provides an elegant solution to guaranteeing certain elusive types of consistency in scenes produced by multiple scene generators which share a common finest-resolution database but which otherwise operate entirely independently. This consistency is achieved by exploiting the freedom of choice of error metric allowed by the algorithm to provide, for example, multiple exact lines-of-sight in real-time. Our methods rely on an off-line pre-processing phase to construct a multi-scale data structure consisting of triangular terrain approximations enhanced ({open_quotes}thickened{close_quotes}) with world-space error information. In real time, this error data is efficiently transformed into screen-space where it is used to guide a greedy top-down triangle subdivision algorithm which produces the desired minimal error continuous terrain mesh. Our algorithm has been implemented and it operates at real-time rates.

  9. Terrain perception for robot navigation

    Science.gov (United States)

    Karlsen, Robert E.; Witus, Gary

    2007-04-01

    This paper presents a method to forecast terrain trafficability from visual appearance. During training, the system identifies a set of image chips (or exemplars) that span the range of terrain appearance. Each chip is assigned a vector tag of vehicle-terrain interaction characteristics that are obtained from simple performance models and on-board sensors, as the vehicle traverses the terrain. The system uses the exemplars to segment images into regions, based on visual similarity to the terrain patches observed during training, and assigns the appropriate vehicle-terrain interaction tag to them. This methodology will therefore allow the online forecasting of vehicle performance on upcoming terrain. Currently, the system uses a fuzzy c-means clustering algorithm for training. In this paper, we explore a number of different features for characterizing the visual appearance of the terrain and measure their effect on the prediction of vehicle performance.

  10. The rph2 gene is responsible for high level resistance to phosphine in independent field strains of Rhyzopertha dominica.

    Science.gov (United States)

    Mau, Yosep S; Collins, Patrick J; Daglish, Gregory J; Nayak, Manoj K; Ebert, Paul R

    2012-01-01

    The lesser grain borer Rhyzopertha dominica (F.) is one of the most destructive insect pests of stored grain. This pest has been controlled successfully by fumigation with phosphine for the last several decades, though strong resistance to phosphine in many countries has raised concern about the long term usefulness of this control method. Previous genetic analysis of strongly resistant (SR) R. dominica from three widely geographically dispersed regions of Australia, Queensland (SR(QLD)), New South Wales (SR(NSW)) and South Australia (SR(SA)), revealed a resistance allele in the rph1 gene in all three strains. The present study confirms that the rph1 gene contributes to resistance in a fourth strongly resistant strain, SR2(QLD), also from Queensland. The previously described rph2 gene, which interacts synergistically with rph1 gene, confers strong resistance on SR(QLD) and SR(NSW). We now provide strong circumstantial evidence that weak alleles of rph2, together with rph1, contribute to the strong resistance phenotypes of SR(SA) and SR2(QLD). To test the notion that rph1 and rph2 are solely responsible for the strong resistance phenotype of all resistant R. dominica, we created a strain derived by hybridising the four strongly resistant lines. Following repeated selection for survival at extreme rates of phosphine exposure, we found only slightly enhanced resistance. This suggests that a single sequence of genetic changes was responsible for the development of resistance in these insects.

  11. The rph2 gene is responsible for high level resistance to phosphine in independent field strains of Rhyzopertha dominica.

    Directory of Open Access Journals (Sweden)

    Yosep S Mau

    Full Text Available The lesser grain borer Rhyzopertha dominica (F. is one of the most destructive insect pests of stored grain. This pest has been controlled successfully by fumigation with phosphine for the last several decades, though strong resistance to phosphine in many countries has raised concern about the long term usefulness of this control method. Previous genetic analysis of strongly resistant (SR R. dominica from three widely geographically dispersed regions of Australia, Queensland (SR(QLD, New South Wales (SR(NSW and South Australia (SR(SA, revealed a resistance allele in the rph1 gene in all three strains. The present study confirms that the rph1 gene contributes to resistance in a fourth strongly resistant strain, SR2(QLD, also from Queensland. The previously described rph2 gene, which interacts synergistically with rph1 gene, confers strong resistance on SR(QLD and SR(NSW. We now provide strong circumstantial evidence that weak alleles of rph2, together with rph1, contribute to the strong resistance phenotypes of SR(SA and SR2(QLD. To test the notion that rph1 and rph2 are solely responsible for the strong resistance phenotype of all resistant R. dominica, we created a strain derived by hybridising the four strongly resistant lines. Following repeated selection for survival at extreme rates of phosphine exposure, we found only slightly enhanced resistance. This suggests that a single sequence of genetic changes was responsible for the development of resistance in these insects.

  12. The rph2 Gene Is Responsible for High Level Resistance to Phosphine in Independent Field Strains of Rhyzopertha dominica

    Science.gov (United States)

    Mau, Yosep S.; Collins, Patrick J.; Daglish, Gregory J.; Nayak, Manoj K.; Ebert, Paul R.

    2012-01-01

    The lesser grain borer Rhyzopertha dominica (F.) is one of the most destructive insect pests of stored grain. This pest has been controlled successfully by fumigation with phosphine for the last several decades, though strong resistance to phosphine in many countries has raised concern about the long term usefulness of this control method. Previous genetic analysis of strongly resistant (SR) R. dominica from three widely geographically dispersed regions of Australia, Queensland (SRQLD), New South Wales (SRNSW) and South Australia (SRSA), revealed a resistance allele in the rph1 gene in all three strains. The present study confirms that the rph1 gene contributes to resistance in a fourth strongly resistant strain, SR2QLD, also from Queensland. The previously described rph2 gene, which interacts synergistically with rph1 gene, confers strong resistance on SRQLD and SRNSW. We now provide strong circumstantial evidence that weak alleles of rph2, together with rph1, contribute to the strong resistance phenotypes of SRSA and SR2QLD. To test the notion that rph1 and rph2 are solely responsible for the strong resistance phenotype of all resistant R. dominica, we created a strain derived by hybridising the four strongly resistant lines. Following repeated selection for survival at extreme rates of phosphine exposure, we found only slightly enhanced resistance. This suggests that a single sequence of genetic changes was responsible for the development of resistance in these insects. PMID:22461899

  13. Effect of ozone on respiration of adult Sitophilus oryzae (L.), Tribolium castaneum (Herbst) and Rhyzopertha dominica (F.).

    Science.gov (United States)

    Lu, Baoqian; Ren, Yonglin; Du, Yu-zhou; Fu, Yueguan; Gu, Jie

    2009-10-01

    The effect of ozone on the respiration of three species of adult stored-product Coleoptera was tested in an air-tight flask. Sitophilus oryzae (L.), Rhyzopertha dominica (F.) and Tribolium castaneum (Herbst) adults were exposed to atmosphere containing 0.1, 0.2 or 0.4microg/ml initial ozone at 23-25 degrees C and 50% r.h. Carbon dioxide (CO(2)) production reflected the respiration rates of insects and was determined with a gas chromatograph (GC). The experiments showed that the effects of ozone on respiration had two distinct phases. Phase 1 involved a lower respiration rate of the adult stored-product Coleoptera under ozone atmosphere and reflected the need for insects to reduce ozone toxicity. After 1h, CO(2) production of S. oryzae was 3.19, 2.63, 2.27 and 1.99microl/mg for the ozone concentration of 0, 0.1, 0.2 and 0.4microg/ml, respectively. The results also showed that there were decreases in the rate of respiration in R. dominica and T. castaneum with an increase in ozone concentration. During phase 2, respiration of S. oryzae, R. dominica, and T. castaneum adults treated with ozone increased as the ozone degraded to oxygen. After 7h, the effect of ozone on CO(2) production, relative to the control, changed from a decrease to an increase. The findings in relation to control strategies were discussed.

  14. Urban Terrain Zone Characteristics

    Science.gov (United States)

    1987-09-01

    GROUP SUB-GROUP MOUT Urban Geography 13 13 MOBA Structures 15 06 06.07 Combat in Cities 19. ABSTRACT (Continue on reverie if necessary ind identify by...was introduced by the autbor in conjunction with the development end use of a computer-assisted game (ACABUG) for combat development studies...Activity (TRASANA) under the title of American Canadian Australian British Urban Game . (ACABUG) Urban Terrain Classification System. The claseification

  15. The geothermal resource in Dominica : from the class room to the fieldwork

    Science.gov (United States)

    Olivia, Urity

    2014-05-01

    In Martinique and more generally in the Caribbean area, the Global warming is not only a topic you can read about in a scientific article but a true issue in the everyday life of the inhabitants. Many effects of the increase of the sea level or the erosion can be observed in the environment. For example, beaches are being destroyed, frightening buildings built on the seafront. This is not only an environmental issue but a touristic and economical one. By the way it is a problem to give a new home to these inhabitants who are now losing their houses. So, with their limited territory and their economy depending on tourism, the islands of the Lesser Antilles have a big challenge which is to find some solutions to minimize the effects of the Global warming on their populations. Anyway, anthropic activities and particularly the using of fossil fuels are named to be responsible for a big part of the climate changes. Knowing this allows us to understand that the Caribbean countries have to develop renewable energies. Guadeloupe and Dominica are two good examples of these islands, where the politicians have already decided to use sustainable energies. They use geothermal energy and hydroelectricity to provide to the families' needs. In this way, the Dominican government, with finances from The European Union, Guadeloupe and Martinique decided to explore the geothermal resource in the island and to build a plant in the area of Roseau Valley. Therefore the students and I, we have decided to study the geology of Dominica in order to find the origin of the geothermal resource and to get more information about the geothermal power plant project. Furthermore, we wanted to understand how this resource is used by the locals and to determine the impact of the presence of the future plant in the chosen sites. In the poster to come, I have chosen to introduce the "journey in Dominica" and the fieldwork that I have realized with my students of upper sixth form. The poster will focus

  16. Evolving volcanism at the tip of a propagating arc: The earliest high-Mg andesites in northern New Zealand

    Science.gov (United States)

    Booden, Mathijs A.; Smith, Ian E. M.; Mauk, Jeffrey L.; Black, Philippa M.

    2010-08-01

    A NNW-striking string of isolated volcanic centers, the Kiwitahi chain, erupted between 15 and 5.5 Ma in northern New Zealand. Prior to 6.2 Ma, the erupted rocks were plagioclase- and hornblende-dominated andesites, which are geochemically comparable to coeval andesites erupted in the nearby, much larger Coromandel Volcanic Zone (CVZ). Compared to CVZ andesites, however, the Kiwitahi andesites show more subdued incompatible element enrichments, and they generally have relatively unradiogenic Sr isotope compositions. These features, and the small eruption volumes involved, suggest that the Kiwitahi centers formed over the edge of a magmatic system that was centered on the CVZ. The Kiwitahi centers progressively become younger towards the SSE representing the migration over the time of the edge of this magmatic system. Between 6.2 and 5.5 Ma, four centers at the southern end of the chain erupted pyroxene-dominated, high-magnesium andesites that are geochemically unlike coeval andesites in the CVZ, but similar to Quaternary high-Mg andesites erupted along the western edge of the Taupo Volcanic Zone. These are the earliest known high-Mg andesites in northern New Zealand; their appearance may mark the inception of the current configuration where high-Mg andesite eruptions precede regular andesitic volcanism at the leading edge of the arc.

  17. A dearth of intermediate melts at subduction zone volcanoes and the petrogenesis of arc andesites.

    Science.gov (United States)

    Reubi, Olivier; Blundy, Jon

    2009-10-29

    Andesites represent a large proportion of the magmas erupted at continental arc volcanoes and are regarded as a major component in the formation of continental crust. Andesite petrogenesis is therefore fundamental in terms of both volcanic hazard and differentiation of the Earth. Andesites typically contain a significant proportion of crystals showing disequilibrium petrographic characteristics indicative of mixing or mingling between silicic and mafic magmas, which fuels a long-standing debate regarding the significance of these processes in andesite petrogenesis and ultimately questions the abundance of true liquids with andesitic composition. Central to this debate is the distinction between liquids (or melts) and magmas, mixtures of liquids with crystals, which may or may not be co-genetic. With this distinction comes the realization that bulk-rock chemical analyses of petrologically complex andesites can lead to a blurred picture of the fundamental processes behind arc magmatism. Here we present an alternative view of andesite petrogenesis, based on a review of quenched glassy melt inclusions trapped in phenocrysts, whole-rock chemistry, and high-pressure and high-temperature experiments. We argue that true liquids of intermediate composition (59 to 66 wt% SiO(2)) are far less common in the sub-volcanic reservoirs of arc volcanoes than is suggested by the abundance of erupted magma within this compositional range. Effective mingling within upper crustal magmatic reservoirs obscures a compositional bimodality of melts ascending from the lower crust, and masks the fundamental role of silicic melts (>/=66 wt% SiO(2)) beneath intermediate arc volcanoes. This alternative view resolves several puzzling aspects of arc volcanism and provides important clues to the integration of plutonic and volcanic records.

  18. Evaluation of Standard Loose Plastic Packaging for the Management of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebriondiae).

    Science.gov (United States)

    Hassan, Muhammad Waqar; Gulraize; Ali, Usman; Ur Rehman, Fazal; Najeeb, Hafsa; Sohail, Maryam; Irsa, Bakhtawar; Muzaffar, Zubaria; Chaudhry, Muhammad Shafiq

    2016-01-01

    Three standard foodstuff plastic packaging namely polyethylene (PE), polypropylene (PP), and polyvinylchloride (PVC) were evaluated for management of lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and red flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Resistance parameters in packaging were recorded as punctures, holes, penetrations, sealing defects, and invasions with two thicknesses and tested for two lengths of time. Damages like punctures, holes and penetrations by both insects were more in PE packaging however R. dominica made more penetrations in PP than in PE. For both insects sealing defects and invasions were predominant in PVC than in others. Thickness did not affect significantly damage types but significantly more holes and penetrations by R. dominica were in less thickness. Punctures and holes by R. dominica were more after less time period but other damages in packaging were more after more time period. However for T. castaneum all sorts of damages were seen more after more time period. Overall categorization between two insects showed R. dominica made more penetrations and T. castaneum made more invasions compared with their counterparts. Pictures were taken under camera fitted microscope to magnify punctures and holes in different packaging and thicknesses. Insect mortality due to phosphine was more in PP and PE packaging and least in PVC packaging and thickness effect was marginal. T. castaneum mortality was significantly more after 48 h than after 24 h. Damages extent in packaging and fumigation results showed PP to be the best of three packaging materials to manage these insects.

  19. Evaluation of Standard Loose Plastic Packaging for the Management of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebriondiae)

    Science.gov (United States)

    Hassan, Muhammad Waqar; Gulraize; Ali, Usman; Ur Rehman, Fazal; Najeeb, Hafsa; Sohail, Maryam; Irsa, Bakhtawar; Muzaffar, Zubaria; Chaudhry, Muhammad Shafiq

    2016-01-01

    Three standard foodstuff plastic packaging namely polyethylene (PE), polypropylene (PP), and polyvinylchloride (PVC) were evaluated for management of lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and red flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Resistance parameters in packaging were recorded as punctures, holes, penetrations, sealing defects, and invasions with two thicknesses and tested for two lengths of time. Damages like punctures, holes and penetrations by both insects were more in PE packaging however R. dominica made more penetrations in PP than in PE. For both insects sealing defects and invasions were predominant in PVC than in others. Thickness did not affect significantly damage types but significantly more holes and penetrations by R. dominica were in less thickness. Punctures and holes by R. dominica were more after less time period but other damages in packaging were more after more time period. However for T. castaneum all sorts of damages were seen more after more time period. Overall categorization between two insects showed R. dominica made more penetrations and T. castaneum made more invasions compared with their counterparts. Pictures were taken under camera fitted microscope to magnify punctures and holes in different packaging and thicknesses. Insect mortality due to phosphine was more in PP and PE packaging and least in PVC packaging and thickness effect was marginal. T. castaneum mortality was significantly more after 48 h than after 24 h. Damages extent in packaging and fumigation results showed PP to be the best of three packaging materials to manage these insects. PMID:27638958

  20. Mechanistic studies of antiproliferative effects of Salvia triloba and Salvia dominica (Lamiaceae) on breast cancer cell lines (MCF7 and T47D).

    Science.gov (United States)

    Abu-Dahab, Rana; Abdallah, Maha R; Kasabri, Violet; Mhaidat, Nizar M; Afifi, Fatma U

    2014-01-01

    Ethanol extracts obtained from two Salvia species, S. triloba and S. dominica, collected from the flora of Jordan, were evaluated for their antiproliferative activity against MCF7 and T47D breast cancer cell lines by the sulforhodamine B assay. The ethanol extracts were biologically active with IC50 values of (29.89 ±0.92) and (38.91 ±2.44) μg/mL for S. triloba against MCF7 and T47D cells, respectively, and (5.83 ±0.51) and (12.83 ±0.64) μg/mL for S. dominica against MCF7 and T47D cells, respectively. Flow cytometry analysis and the annexinV-propidium iodide (PI) assay revealed apoptosismediated, and to a lesser extent necrosis-induced, cell death by the S. triloba and S. dominica ethanolic extracts in T47D cells. The mechanism of apoptosis was further investigated by determining the levels of p53, p21/WAF1, FasL (Fas ligand), and sFas (Fas/APO-1). The extract from S. triloba induced a more pronounced enrichment in cytoplasmic mono- and oligonucleosomes than that from S. dominica (p Salvia spp. did not enhance p53 levels, and apoptosis induced by them was not caspase-8- or sFas/FasL-dependent. Thus, our findings indicate that S. triloba and S. dominica ethanolic extracts may be useful in breast cancer management/treatment via proapoptotic cytotoxic mechanisms.

  1. Implications of coral harvest and transplantation on reefs in northwestern Dominica

    Directory of Open Access Journals (Sweden)

    Andrew W Bruckner

    2010-10-01

    Full Text Available In June, 2002, the government of Dominica requested assistance in evaluating the coral culture and transplantation activities being undertaken by Oceanographic Institute of Dominica (OID, a coral farm culturing both western Atlantic and Indo-Pacific corals for restoration and commercial sales. We assessed the culture facilities of OID, the condition of reefs, potential impacts of coral collection and benefits of coral transplantation. Coral reefs (9 reefs, 3-20m depth were characterized by 35 species of scleractinian corals and a live coral cover of 8-35%. Early colonizing, brooders such as Porites astreoides (14.8% of all corals, P. porites (14.8%, Meandrina meandrites (14.7% and Agaricia agaricites (9.1% were the most abundant corals, but colonies were mostly small (mean=25cm diameter. Montastraea annularis (complex was the other dominant taxa (20.8% of all corals and colonies were larger (mean=70cm. Corals (pooled species were missing an average of 20% of their tissue, with a mean of 1.4% recent mortality. Coral diseases affected 6.4% of all colonies, with the highest prevalence at Cabrits West (11.0%, Douglas Bay (12.2% and Coconut Outer reef (20.7%. White plague and yellow band disease were causing the greatest loss of tissue, especially among M. annularis (complex, with localized impacts from corallivores, overgrowth by macroalgae, storm damage and sedimentation. While the reefs appeared to be undergoing substantial decline, restoration efforts by OID were unlikely to promote recovery. No Pacific species were identified at OID restoration sites, yet species chosen for transplantation with highest survival included short-lived brooders (Agaricia and Porites that were abundant in restoration sites, as well as non-reef builders (Palythoa and Erythropodium that monopolize substrates and overgrow corals. The species of highest value for restoration (massive broadcast spawners showed low survivorship and unrestored populations of these species

  2. Toxicity of some essential oils and plant extracts against Sitophilus oryzea, Aconthocelides obtectus and Rhizoperta dominica

    Science.gov (United States)

    Şimşek, Şeyda; Yaman, Cennet; Yarımoǧlu, Berkan; Yılmaz, Ayşegül

    2017-04-01

    In the present study, experiments were conducted to investigate fumigant toxicity of the essential oil from Myrtus sp plants for adult Aconthocelides obtectus, Sitophilus oryzea and Rhizoperta dominica in vitro conditions. The essential oils were isolated with the water distillation method by Neo-Clevenger apparatus. During the study 10% (v/v) doses of oils in 20 cc of compressed rubber-capped glass tubes were used. After 24 hours mortality rates of the essential oil were compared. Myrtus sp essential oil showed the highest fumigant toxicity on A. obtectus (46.66%). The lowest fumigant toxicity on S. oryzea (8.88%). The contact toxicity plant extracts (Prangos ferulacea, Alkanna orientalis, Myrtus communis) were tested against S. oryzea under laboratory conditions. Single dose contact toxicity effects of plant extracts were tested on S. oryzea adults via applying 1 µl extract suspension (10% w/v) to individual insect. The greatest contact toxicity to S. oryzea adults was observed with M. communis (43.33%) and A. orientalis (41.11%) extracts. P. ferulacea (34.44%) extracts produced moderate toxicity to S. oryzea adults.

  3. Information measures for terrain visualization

    Science.gov (United States)

    Bonaventura, Xavier; Sima, Aleksandra A.; Feixas, Miquel; Buckley, Simon J.; Sbert, Mateu; Howell, John A.

    2017-02-01

    Many quantitative and qualitative studies in geoscience research are based on digital elevation models (DEMs) and 3D surfaces to aid understanding of natural and anthropogenically-influenced topography. As well as their quantitative uses, the visual representation of DEMs can add valuable information for identifying and interpreting topographic features. However, choice of viewpoints and rendering styles may not always be intuitive, especially when terrain data are augmented with digital image texture. In this paper, an information-theoretic framework for object understanding is applied to terrain visualization and terrain view selection. From a visibility channel between a set of viewpoints and the component polygons of a 3D terrain model, we obtain three polygonal information measures. These measures are used to visualize the information associated with each polygon of the terrain model. In order to enhance the perception of the terrain's shape, we explore the effect of combining the calculated information measures with the supplementary digital image texture. From polygonal information, we also introduce a method to select a set of representative views of the terrain model. Finally, we evaluate the behaviour of the proposed techniques using example datasets. A publicly available framework for both the visualization and the view selection of a terrain has been created in order to provide the possibility to analyse any terrain model.

  4. Eastern Siberia terrain intelligence

    Science.gov (United States)

    ,

    1942-01-01

    The following folio of terrain intelligence maps, charts and explanatory tables represent an attempt to bring together available data on natural physical conditions such as will affect military operations in Eastern Siberia. The area covered is the easternmost section of the U.S.S.R.; that is the area east of the Yenisei River. Each map and accompanying table is devoted· to a specialized set of problems; together they cover such subjects as geology, construction materials, mineral fuels, terrain, water supply, rivers and climate. The data is somewhat generalized due to the scale of treatment as well as to the scarcity of basic data. Each of the maps are rated as to reliability according to the reliability scale on the following page. Considerable of the data shown is of an interpretative nature, although precise data from literature was used wherever possible. The maps and tables were compiled  by a special group from the United States Geological Survey in cooperation with the Intelligence Branch of the Office, Chief of Engineers, War Department.

  5. Prediction models in complex terrain

    DEFF Research Database (Denmark)

    Marti, I.; Nielsen, Torben Skov; Madsen, Henrik

    2001-01-01

    The objective of the work is to investigatethe performance of HIRLAM in complex terrain when used as input to energy production forecasting models, and to develop a statistical model to adapt HIRLAM prediction to the wind farm. The features of the terrain, specially the topography, influence...

  6. Diagnostic Molecular Markers for Phosphine Resistance in U.S. Populations of Tribolium castaneum and Rhyzopertha dominica

    Science.gov (United States)

    Chen, Zhaorigetu; Schlipalius, David; Opit, George; Subramanyam, Bhadriraju; Phillips, Thomas W.

    2015-01-01

    Stored product beetles that are resistant to the fumigant pesticide phosphine (hydrogen phosphide) gas have been reported for more than 40 years in many places worldwide. Traditionally, determination of phosphine resistance in stored product beetles is based on a discriminating dose bioassay that can take up to two weeks to evaluate. We developed a diagnostic cleaved amplified polymorphic sequence method, CAPS, to detect individuals with alleles for strong resistance to phosphine in populations of the red flour beetle, Tribolium castaneum, and the lesser grain borer, Rhyzopertha dominica, according to a single nucleotide mutation in the dihydrolipoamide dehydrogenase (DLD) gene. We initially isolated and sequenced the DLD genes from susceptible and strongly resistant populations of both species. The corresponding amino acid sequences were then deduced. A single amino acid mutation in DLD in populations of T. castaneum and R. dominica with strong resistance was identified as P45S in T. castaneum and P49S in R. dominica, both collected from northern Oklahoma, USA. PCR products containing these mutations were digested by the restriction enzymes MboI and BstNI, which revealed presence or absence, respectively of the resistant (R) allele and allowed inference of genotypes with that allele. Seven populations of T. castaneum from Kansas were subjected to discriminating dose bioassays for the weak and strong resistance phenotypes. Application of CAPS to these seven populations confirmed the R allele was in high frequency in the strongly resistant populations, and was absent or at a lower frequency in populations with weak resistance, which suggests that these populations with a low frequency of the R allele have the potential for selection of the strong resistance phenotype. CAPS markers for strong phosphine resistance will help to detect and confirm resistant beetles and can facilitate resistance management actions against a given pest population. PMID:25826251

  7. Diagnostic molecular markers for phosphine resistance in U.S. populations of Tribolium castaneum and Rhyzopertha dominica.

    Science.gov (United States)

    Chen, Zhaorigetu; Schlipalius, David; Opit, George; Subramanyam, Bhadriraju; Phillips, Thomas W

    2015-01-01

    Stored product beetles that are resistant to the fumigant pesticide phosphine (hydrogen phosphide) gas have been reported for more than 40 years in many places worldwide. Traditionally, determination of phosphine resistance in stored product beetles is based on a discriminating dose bioassay that can take up to two weeks to evaluate. We developed a diagnostic cleaved amplified polymorphic sequence method, CAPS, to detect individuals with alleles for strong resistance to phosphine in populations of the red flour beetle, Tribolium castaneum, and the lesser grain borer, Rhyzopertha dominica, according to a single nucleotide mutation in the dihydrolipoamide dehydrogenase (DLD) gene. We initially isolated and sequenced the DLD genes from susceptible and strongly resistant populations of both species. The corresponding amino acid sequences were then deduced. A single amino acid mutation in DLD in populations of T. castaneum and R. dominica with strong resistance was identified as P45S in T. castaneum and P49S in R. dominica, both collected from northern Oklahoma, USA. PCR products containing these mutations were digested by the restriction enzymes MboI and BstNI, which revealed presence or absence, respectively of the resistant (R) allele and allowed inference of genotypes with that allele. Seven populations of T. castaneum from Kansas were subjected to discriminating dose bioassays for the weak and strong resistance phenotypes. Application of CAPS to these seven populations confirmed the R allele was in high frequency in the strongly resistant populations, and was absent or at a lower frequency in populations with weak resistance, which suggests that these populations with a low frequency of the R allele have the potential for selection of the strong resistance phenotype. CAPS markers for strong phosphine resistance will help to detect and confirm resistant beetles and can facilitate resistance management actions against a given pest population.

  8. Diagnostic molecular markers for phosphine resistance in U.S. populations of Tribolium castaneum and Rhyzopertha dominica.

    Directory of Open Access Journals (Sweden)

    Zhaorigetu Chen

    Full Text Available Stored product beetles that are resistant to the fumigant pesticide phosphine (hydrogen phosphide gas have been reported for more than 40 years in many places worldwide. Traditionally, determination of phosphine resistance in stored product beetles is based on a discriminating dose bioassay that can take up to two weeks to evaluate. We developed a diagnostic cleaved amplified polymorphic sequence method, CAPS, to detect individuals with alleles for strong resistance to phosphine in populations of the red flour beetle, Tribolium castaneum, and the lesser grain borer, Rhyzopertha dominica, according to a single nucleotide mutation in the dihydrolipoamide dehydrogenase (DLD gene. We initially isolated and sequenced the DLD genes from susceptible and strongly resistant populations of both species. The corresponding amino acid sequences were then deduced. A single amino acid mutation in DLD in populations of T. castaneum and R. dominica with strong resistance was identified as P45S in T. castaneum and P49S in R. dominica, both collected from northern Oklahoma, USA. PCR products containing these mutations were digested by the restriction enzymes MboI and BstNI, which revealed presence or absence, respectively of the resistant (R allele and allowed inference of genotypes with that allele. Seven populations of T. castaneum from Kansas were subjected to discriminating dose bioassays for the weak and strong resistance phenotypes. Application of CAPS to these seven populations confirmed the R allele was in high frequency in the strongly resistant populations, and was absent or at a lower frequency in populations with weak resistance, which suggests that these populations with a low frequency of the R allele have the potential for selection of the strong resistance phenotype. CAPS markers for strong phosphine resistance will help to detect and confirm resistant beetles and can facilitate resistance management actions against a given pest population.

  9. Turbulence measurements over complex terrain

    Science.gov (United States)

    Skupniewicz, Charles E.; Kamada, Ray F.; Schacher, Gordon E.

    1989-07-01

    Horizontal turbulence measurements obtained from 22 wind sensors located on 9 towers in a mountainous coastal area are described and categorized by stability and terrain. Vector wind time series are high-pass filtered, and lateral and longitudinal wind speed variance is calculated for averaging times ranging from 15 s to 2 h. Parameterizations of the functional dependence of variance on averaging time are discussed, and a modification of Panofsky's (1988) uniform terrain technique applicable to complex terrain is presented. The parameterization is applied to the data and shown to be more realistic than a less complicated power law technique. The parameter values are shown to be different than the flat terrain cases of Kaimal et al. (1972), and are primarily a function of sensor location within the complex terrain. The parameters are also examined in terms of their dependence upon season, stability, marine boundary-layer height, and measurement height.

  10. Polygonal terrains on Mars

    Directory of Open Access Journals (Sweden)

    Pedro Pina

    2009-06-01

    Full Text Available The presence of water ice on Mars is well established. Some featureson the planet point to the occurrence of processes similar to those that take place in periglacial areas of Earth. One of the clues for this is the existence of small-scale polygonal terrains. In this paper, we present a methodology that aims at the automated identification of polygonal patterns on high-spatial resolution images of the surface of Mars. In the context of the research project TERPOLI, this step will be complemented with a full characterization, in both geometric and topological terms, of thenetworks detected. In this manner, we hope to collect data that will lead to a better understanding of the conditions of formation of the polygons, and of their temporal evolution; namely, we intend to identify different groups of polygons and to compare them with terrestrial examples.

  11. Turbulence in complex terrain

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Jakob [Risoe National Lab., Wind Energy and Atmosheric Physics Dept., Roskilde (Denmark)

    1999-03-01

    The purpose of this work is to develop a model of the spectral velocity-tensor in neutral flow over complex terrain. The resulting equations are implemented in a computer code using the mean flow generated by a linear mean flow model as input. It estimates turbulence structure over hills (except on the lee side if recirculation is present) in the so-called outer layer and also models the changes in turbulence statistics in the vicinity roughness changes. The generated turbulence fields are suitable as input for dynamic load calculations on wind turbines and other tall structures and is under implementation in the collection of programs called WA{sup s}P Engineering. (au) EFP-97; EU-JOULE-3. 15 refs.

  12. Phreatic activity in the Valley of Desolation, Dominica (Lesser Antilles) - constraints from field investigations and experimental volcanology

    Science.gov (United States)

    Mayer, Klaus; Scheu, Bettina; Montanaro, Cristian; Yilmaz, Tim; Aßbichler, Donja; Gilg, H. Albert; Dingwell, Donald B.

    2016-04-01

    Dominica has one of the highest concentrations of potentially active volcanoes worldwide, flanked by abundant surficial geothermal manifestations: The Boiling Lake - Valley of Desolation area represents one of the most vigorous ones, hosting hot springs, mud pools, fumaroles, and steam vents. Intense alteration, together with predominantly phreatic explosive features of varying scales, characterize the whole area. The last historic eruptions in Dominica occurred at the Valley of Desolation. Phreatic eruptions are also the most likely type of volcanic activity to occur in the near future at Dominica in general and the Valley of Desolation in particular. Phreatic eruptions are up to date largely unpredictable in time and magnitude, strongly asking for constraints of eruptive conditions as well as trigger mechanisms. We conducted sampling and field mapping, together with the determination of in situ physical (density, humidity, permeability) and mechanical (strength, stiffness) properties to characterize the main active surficial area which possesses a high probability for a phreatic event. Rapid decompression experiments performed on selected samples from this area give insight into the fragmentation and ejection behavior of steam driven eruptions. These experiments were flanked by chemical analyses and laboratory measurements as porosity and granulometry. The results indicate that advanced argillic alteration in the proximity of degassing vents significantly changes the rock properties, which in turn play a crucial role for the degassing of hydrothermal systems. High-temperature acidic fluids lead to an intense alteration of the host rocks, and thereby cause the formation of a kaolinite-rich, low permeable layer above the vent. In addition, alteration enhances slope instabilities causing landslides which may cover and clog the outgassing vents. Such processes increase the likelihood of the site experiencing a pressurization, which may result in a steam

  13. Validating national landslide susceptibility and hazard maps for Caribbean island countries: the case of Dominica and tropical storm Erika.

    Science.gov (United States)

    van Westen, Cees; Jetten, Victor; Alkema, Dinand

    2016-04-01

    The aim of this study was to generate national-scale landslide susceptibility and hazard maps for four Caribbean islands, as part of the World Bank project CHARIM (Caribbean Handbook on Disaster Geoinformation Management, www.charim.net). This paper focuses on the results for the island country of Dominica, located in the Eastern part of the Caribbean, in-between Guadalupe and Martinique. The available data turned out to be insufficient to generate reliable results. We therefore generated a new database of disaster events for Dominica using all available data, making use of many different sources. We compiled landslide inventories for five recent rainfall events from the maintenance records of the Ministry of Public Works, and generated a completely new landslide inventory using multi-temporal visual image interpretation, and generated an extensive landslide database for Dominica. We analyzed the triggering conditions for landslides as far as was possible given the available data, and generated rainfall magnitude-frequency relations. We applied a method for landslide susceptibility assessment which combined bi-variate statistical analysis, that provided indications on the importance of the possible contributing factors, with an expert-based iterative weighing approach using Spatial Multi-Criteria Evaluation. The method is transparent, as the stakeholders (e.g. the engineers and planners from the four countries) and other consultants can consult the criteria trees and evaluate the standardization and weights, and make adjustments. The landslide susceptibility map was converted into a landslide hazard map using landslide density and frequencies for so called major, moderate and minor triggering events. The landslide hazard map was produced in May 2015. A major rainfall event occurred on Dominica following the passage of tropical storm Erika on 26 to 28 August 2015. An event-based landslide inventory for this event was produced by UNOSAT using very high resolution

  14. On characterizing terrain visibility graphs

    Directory of Open Access Journals (Sweden)

    William Evans

    2015-06-01

    Full Text Available A terrain is an $x$-monotone polygonal line in the $xy$-plane. Two vertices of a terrain are mutually visible if and only if there is no terrain vertex on or above the open line segment connecting them. A graph whose vertices represent terrain vertices and whose edges represent mutually visible pairs of terrain vertices is called a terrain visibility graph. We would like to find properties that are both necessary and sufficient for a graph to be a terrain visibility graph; that is, we would like to characterize terrain visibility graphs.Abello et al. [Discrete and Computational Geometry, 14(3:331--358, 1995] showed that all terrain visibility graphs are “persistent”. They showed that the visibility information of a terrain point set implies some ordering requirements on the slopes of the lines connecting pairs of points in any realization, and as a step towards showing sufficiency, they proved that for any persistent graph $M$ there is a total order on the slopes of the (pseudo lines in a generalized configuration of points whose visibility graph is $M$.We give a much simpler proof of this result by establishing an orientation to every triple of vertices, reflecting some slope ordering requirements that are consistent with $M$ being the visibility graph, and prove that these requirements form a partial order. We give a faster algorithm to construct a total order on the slopes. Our approach attempts to clarify the implications of the graph theoretic properties on the ordering of the slopes, and may be interpreted as defining properties on an underlying oriented matroid that we show is a restricted type of $3$-signotope.

  15. Chemical weathering and erosion rates in the Lesser Antilles: An overview in Guadeloupe, Martinique and Dominica

    Science.gov (United States)

    Rad, Sétareh; Rivé, Karine; Vittecoq, Benoit; Cerdan, Olivier; Allègre, Claude Jean

    2013-08-01

    Guadeloupe, Martinique and Dominica islands, like numerous tropical environments, have extreme weathering regimes. Physical denudation is mainly controlled by landslides, which reflect the torrential dynamics of the rivers. In Guadeloupe, the mechanical weathering rates vary between 800 and 4000 t/km2/yr. The lithology is very porous with high infiltration rates, which suggests that most of the element fluxes are produced in the subsurface, with chemical erosion rates 2-5 times higher than the rates from surface water. We show how the kinetics of chemical weathering rates depend on the age of the lava and subsurface circulation. In addition, erosion timescales were calculated from U-series analyses of river sediments. Our results show a broad range: 0-150 ka in Martinique and 0-60 ka in Guadeloupe. We evaluated residence times in river water on the basis of the dissolved load analyses. It appears that water circulation is globally 3-fold longer for subsurface water than for surficial water (Rad et al. 2011a,b). Moreover, these islands are highly impacted by agriculture. However, contrary to what one might think, our results show that human activity does not disturb critical zone processes. Indeed, we show that among the combined impacts of all parameters (climate, runoff, slope, vegetation, etc.), the basin's age seems to be the control parameter for chemical weathering and land use—the younger the basin, the higher the weathering rates. We could observe a combined effect between the higher erodibility and a higher climate erosivity of the younger reliefs.

  16. A new species of Lachesilla (Psocodea: 'Psocoptera': Lachesillidae from Dominica, representing a new species group Una especie nueva de Lachesilla (Psocodea: 'Psocoptera': Lachesillidae de Dominica, que representa un nuevo grupo de especies

    Directory of Open Access Journals (Sweden)

    Alfonso N. García Aldrete

    2011-06-01

    Full Text Available A new species of Lachesilla, from Cabrits National Park, St. John's Parish, Dominica, is here described and illustrated. The phallosome is V-shaped, and it is autapomorphic in having the distal ends of the apodeme arms articulated to each clasper. Based on these characters, a new species group is created, close to the L. forcepeta and L. palmera species groups (the latter also diagnosed in this paper. The holotype is deposited in the National Insect Collection (CNIN, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City.Se describe e ilustra una nueva especie de Lachesilla, procedente de Cabrits National Park, St. John's Parish, Dominica. El falosoma tiene forma de V, y es autapomórfico en tener los extremos distales de los brazos articulados a cada clásper. Con base en estos caracteres, se crea un nuevo grupo de especies, cercano a los grupos de L. forcepeta y L. palmera (este último también definido en este trabajo. El holotipo está depositado en la Colección Nacional de Insectos (CNIN, alojada en el Instituto de Biología de la Universidad Nacional Autónoma de México, México, D. F.

  17. Spectral evidence for weathered basalt as an alternative to andesite in the northern lowlands of Mars.

    Science.gov (United States)

    Wyatt, Michael B; McSween, Harry Y

    2002-05-16

    Mineral abundances derived from the analysis of remotely sensed thermal emission data from Mars have been interpreted to indicate that the surface is composed of basalt (Surface Type 1) and andesite (Surface Type 2). The global distribution of these rock types is divided roughly along the planetary dichotomy which separates ancient, heavily cratered crust in the southern hemisphere (basalt) from younger lowland plains in the north (andesite). But the existence of such a large volume of andesite is difficult to reconcile with our present understanding of the geological evolution of Mars. Here we reinterpret martian surface rock lithologies using mineral abundances from previous work and new mineralogies derived from a spectral end-member set representing minerals common in unaltered and low-temperature aqueously altered basalts. Our results continue to indicate the dominance of unaltered basalt in the southern highlands, but reveal that the northern lowlands can be interpreted as weathered basalt as an alternative to andesite. The coincidence between locations of such altered basalt and a suggested northern ocean basin implies that lowland plains material may be composed of basalts weathered under submarine conditions or weathered basaltic sediments transported into this depocentre.

  18. Experimental Study on the Electrical Conductivity of Pyroxene Andesite at High Temperature and High Pressure

    Science.gov (United States)

    Hui, KeShi; Dai, LiDong; Li, HePing; Hu, HaiYing; Jiang, JianJun; Sun, WenQing; Zhang, Hui

    2016-09-01

    The electrical conductivity of pyroxene andesite was in situ measured under conditions of 1.0-2.0 GPa and 673-1073 K using a YJ-3000t multi-anvil press and Solartron-1260 Impedance/Gain-phase analyzer. Experimental results indicate that the electrical conductivities of pyroxene andesite increase with increasing temperature, and the electrical conductivities decrease with the rise of pressure, and the relationship between electrical conductivity (σ) and temperature (T) conforms to an Arrhenius relation within a given pressure and temperature range. When temperature rises up to 873-923 K, the electrical conductivities of pyroxene andesite abruptly increase, and the activation enthalpy increases at this range, which demonstrates that pyroxene andesite starts to dehydrate. By the virtue of the activation enthalpy (0.35-0.42 eV) and the activation volume (-6.75 ± 1.67 cm3/mole) which characterizes the electrical properties of sample after dehydration, we consider that the conduction mechanism is the small polaron conduction before and after dehydration, and that the rise of carrier concentration is the most important reason of increased electrical conductivity.

  19. Pore-space distribution and transport properties of an andesitic intrusion

    Science.gov (United States)

    Jamtveit, Bjørn; Krotkiewski, Marcin; Kobchenko, Maya; Renard, Francois; Angheluta, Luiza

    2014-08-01

    The pore structure of magmatic rocks records processes operating during magma solidification and cooling. It has first order effects on the petrophysical properties of the magmatic rocks, and also influences mass transfer and mineral reactions during subsequent metamorphism or weathering. Here, the pore space characteristics of an andesitic sill intrusion were determined by multiscale resolution computed X-ray microtomography (μ-CT), and the 3D structure was used for transport modeling. Unaltered andesite has a power law distribution of pore volumes over a range of five orders of magnitude. The probability distribution function (PDF) scales with the inverse square of the pore volume (V), PDF∝V-2. This scaling behavior is attributed to the coalescence of pores at crystal-melt boundaries. Large pores are concentrated on the outer margins of amphibole and plagioclase phenocrystals. Incipient weathering of the andesite is associated with preferential growth of weathering products in the largest pores. This can be explained by a model in which diffusion of external components into the porous andesite is controlled by a random network of grain boundaries and/or microfractures. This network preferentially links the larger pores to the system boundaries and it is the major fluid transport pathway, confining incipient weathering into a small fraction of the rock volume only.

  20. Mapping Acid Sulfate Alteration of Basaltic Andesite with Thermal Infrared Data

    Science.gov (United States)

    Vaughan, R. G.; Calvin, W. M.; Hook, S. J.; Taranik, J. V.

    2002-01-01

    Airborne thermal infrared multi- and hyperspectral data sets are used to map sulfate alteration of basaltic andesites near Reno, NV. Alteration includes quartz-alunite, jarosite and a number of clay minerals such as kaolinite and montmorillonite. Additional information is contained in the original extended abstract.

  1. Robot Would Climb Steep Terrain

    Science.gov (United States)

    Kennedy, Brett; Ganino, Anthony; Aghazarian, Hrand; Hogg, Robert; McHerny, Michael; Garrett, Michael

    2007-01-01

    This brief describes the steep terrain access robot (STAR) -- a walking robot that has been proposed for exploring steep terrain on remote planets. The STAR would be able to climb up or down on slopes as steep as vertical, and even beyond vertical to overhangs. Its system of walking mechanisms and controls would be to react forces and maintain stability. To enable the STAR to anchor itself in the terrain on steep slopes to maintain stability and react forces, it would be necessary to equip the tips of the walking legs with new ultrasonic/ sonic drill corers (USDCs) and to develop sensors and control algorithms to enable robust utilization of the USDCs.

  2. Martian terrain - 3D

    Science.gov (United States)

    1997-01-01

    This area of terrain near the Sagan Memorial Station was taken on Sol 3 by the Imager for Mars Pathfinder (IMP). 3D glasses are necessary to identify surface detail.The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.' It stands 1.8 meters above the Martian surface, and has a resolution of two millimeters at a range of two meters.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  3. Effects of combined thiamethoxam and diatomaceous earth on mortality and progeny production of four Pakistani populations of Rhyzopertha dominica (Coleoptera: Bostrychidae) on wheat, rice and maize

    Science.gov (United States)

    Bioassays were conducted to evaluate the effects of combining thiamethoxam at 0.25, 0.5 and 0.75 mg/kg with the diatomaceous earth (DE) formulation, SilicoSec, at the rate of 100 mg/kg against four diverse populations of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) th...

  4. TERRAIN, GADSDEN COUNTY, FL, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. TERRAIN, STEWART COUNTY, TN, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, HOUSTON COUNTY, TN, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, MONROE COUNTY, TN, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, MADISON PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, WILCOX COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. TERRAIN, LARUE COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. TERRAIN, CULLMAN COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. TERRAIN, LOGAN COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. Terrain Data, KENT COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN, OWEN COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. TERRAIN, NEW KENT COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  16. TERRAIN, TAYLOR COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN, NATCHITOCHES PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN Submission for CHICKASAW, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  19. TERRAIN, WAKULLA COUNTY, FL, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. TERRAIN, SUWANNEE COUNTY, FLORIDA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. TERRAIN, LYON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN, MACOMB COUNTY, MI, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  3. TERRAIN, CHILTON COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, COLBERT COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. TERRAIN, BOYLE COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, Catahoula PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, DEKALB COUNTY, TN, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, VERNON PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, EVANGELINE PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. TERRAIN, DALLAS COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. TERRAIN, SEBASTIAN COUNTY, AR, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographical data that were used to create...

  12. TERRAIN, ESCAMBIA COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. TERRAIN, FRANKLIN COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN, CLARK COUNTY, Missouri USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. TERRAIN, RUSSELL COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  16. TERRAIN, Sedgwick COUNTY, Kansas USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN, GRAYSON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, EVANGELINE PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. TERRAIN, SANTA CRUZ COUNTY, AZ

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. TERRAIN, CLARKE COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. TERRAIN, KENTON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN, CAMPBELL COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  3. TERRAIN, MARENGO COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, MARION COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. TERRAIN, CLARK COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, PIKE COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, Concordia PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, Webster COUNTY, Missouri USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, JESSAMINE COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. Terrain Data, Westmoreland COUNTY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. TERRAIN, LEVY COUNTY, FL, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. TERRAIN, FRANKLIN COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. TERRAIN, LIMESTONE COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN, NELSON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. TERRAIN, LAWRENCE COUNTY, Ohio USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  16. TERRAIN, SUMTER COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN, MADISON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, TALLAPOOSA COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. TERRAIN, WALKER COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. TERRAIN, SCOTT COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. TERRAIN, SHELBY COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN, PENDLETON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  3. TERRAIN, CLINTON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, MERCER COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. TERRAIN, CALDWELL COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. TERRAIN, POWELL COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. TERRAIN, HARRISON COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, Robertson COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, RUSSELL COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. The anatomy of an andesite volcano: A time-stratigraphic study of andesite petrogenesis and crustal evolution at Ruapehu volcano, New Zealand

    DEFF Research Database (Denmark)

    Price, R.C.; Gamble, J.A.; Smith, I.E.M.;

    2012-01-01

    Ruapehu, New Zealand’s largest active andesite volcano is located at the southern tip of the Taupo Volcanic Zone (TVZ), the main locus of subduction-related volcanism in the North Island. Geophysical data indicate that crustal thickness transitions from ... Ruapehu. The volcano is built on a basement of Mesozoic metagreywacke and geophysical evidence together with xenoliths contained in lavas indicates that this is underlain by oceanic, meta-igneous lower crust. The present-day Ruapehu edifice has been constructed by a series of eruptive events that produced...

  11. Susceptibility of Rhyzopertha dominica (F. (Coleoptera: Bostrichidae and Sitophilus oryzae (L. (Coleoptera: Curculionidae to Spinosad (Tracer® as a Eco-friendly Biopesticide

    Directory of Open Access Journals (Sweden)

    Reza Sadeghi

    2015-06-01

    Full Text Available Rhyzopertha dominica (F. and Sitophilus oryzae (L. are internal feeder of various stored grains and introducted as major stored product insect pests. Due to the resistance by insect pests and negative effects of synthetic pesticides to the environment, it is necessary to use novel and suitable compounds in insect pest’s management. Spinosad is a bio-insecticide that is derived from fermentation of a bacterium Saccharopolyspora spinosa Mertz and Yao. In the present study, the toxicity of Tracer® as a spinosad based insecticidise was evaluated against R. dominica and S. oryzae. Insect species were kept in stored-products insects rearing room in Agriculture Faculty of Tehran University at 27 ± 2ºC, 65 ± 5% relative humidity. Adult insects were exposed to different concentrations of Tracer® by oral trials for 10 and 20 days exposure periods. The mortality data were subjected to probit analysis using SPSS software to estimate LC (lethal concentration values and their related information. Tracer® showed strong toxicity against the adults of R. dominica and S. oryzae. Maximum mortality was occurred in the concentration of 250 and 80 ppm after 20 days exposure for R. dominica and S. oryzae, respectively. Direct relationship between mortality of insects with concentration and exposure period was found. Probit analysis displayed R. dominica (10-days LC50 = 49.89 ppm was more susceptible than S. oryzae (10-days LC50 = 50.75 ppm to Tracer®. Results of present study stimulated the utilization of Tracer® as an eco-friendly and safe agent for insect pests’ management.

  12. Handling Massive and Dynamic Terrain Data

    DEFF Research Database (Denmark)

    Revsbæk, Morten

    analyzing flood risk and visibility, to producing nautical charts. Many algorithms and much commercial software have been developed to help analyze terrain models. However, significant algorithmic challenges arise from the increasing detail (and therefore size) of modern terrain models. Furthermore, terrain...... we develop so-called I/O-efficient algorithms for a set of well-known terrain analysis problems. First, we present an I/O-efficient algorithm for terrain model simplification. This algorithm can be used in connection with terrain analysis to reduce the topological complexity of a detailed terrain...

  13. Soils derived from Pieniny andesite, Wdżar hill, Outer Carpathians (Poland)

    Science.gov (United States)

    Kajdas, Bartlomiej; Zaleski, Tomasz; Mazurek, Ryszard

    2016-04-01

    Tertiary andesite occurs in only few places in Polish part of the Outer Carpatians. The biggest andesitic body is observed at the Wdżar hill (676 m a.s.l), SE from Kluszkowce village. To the beginning of the 1970s active quarry were located at the hill slope, and from the end of 1990s Wdżar is used as a ski resort. Because Wdżar is the culmination protruding over sandstones and shales of Magura Unit of Outer Carpatians, it gives opportunity to investigate soils derived directly from the andesite. Primary, unaltered andesite contain mainly plagioclase (An28-62), amphibole (hornblende group), clinopiroxene (pigeonite group) and Fe-Ti oxides (Michalik et al., 2004). Quartz in those type of rocks is absent. Andesites from Pieniny Mts. contain low amount of silica (ca. 52-55% wt. in fresh and about 62% wt. in hydrothermally altered rocks), and high amount of CaO (5,5-9,2% wt.) and MgO (0,8-5,5% wt.) (Nejbert et al., 2012). Soils cover on Wdżar hill represents different stages of soil development. Shallow, ca. 15 cm deep, Eutric Leptosols and deeper, 60 cm and over 200 cm deep, Eutric Skeleti Cambisols (Colluvic, Humic) were distinguished. There are significant differences both between the soil groups as well as inside them. Investigated soils have sandy loam, loam and silt loam texture. Surface, organic horizons show acid reaction, but cambic and parent material horizons show neutral reaction. Cation exchange capacity ranges between 526.9 and 298.2 mmol(+)ṡkg-1 in humus horizons and between 451.4 and 225.8 mmol(+)ṡkg-1in cambic and parent material horizons. The amount of exchangeable Ca2+ ranges between 386.8 and 175.8 mmol(+)ṡkg-1 and is about 6 times higher than sum of Mg2+, Na+ and K+ in the soil horizon. Despite of the high amount of Ca2+, there were no active carbonates in investigated soil. The soils, that are developed from the andesite, usualy contain high amount of clays and very low amount of primary quartz. Andesite from Wdżar reveals minor degree

  14. Experimental study into the petrogenesis of crystal-rich basaltic to andesitic magmas at Arenal volcano

    Science.gov (United States)

    Parat, F.; Streck, M. J.; Holtz, F.; Almeev, R.

    2014-08-01

    Arenal volcano is nearly unique among arc volcanoes with its 42 year long (1968-2010) continuous, small-scale activity erupting compositionally monotonous basaltic andesites that also dominate the entire, ~7000 year long, eruptive history. Only mineral zoning records reveal that basaltic andesites are the result of complex, open-system processes deriving minerals from a variety of crystallization environments and including the episodic injections of basalt. The condition of the mafic input as well as the generation of crystal-rich basaltic andesites of the recent, 1968-2010, and earlier eruptions were addressed by an experimental study at 200 MPa, 900-1,050 °C, oxidizing and fluid-saturated conditions with various fluid compositions [H2O/(H2O + CO2) = 0.3-1]. Phase equilibria were determined using a phenocryst-poor (~3 vol%) Arenal-like basalt (50.5-wt% SiO2) from a nearby scoria cone containing olivine (Fo92), plagioclase (An86), clinopyroxene (Mg# = 82) and magnetite (Xulvö = 0.13). Experimental melts generally reproduce observed compositional trends among Arenal samples. Small differences between experimental melts and natural rocks can be explained by open-system processes. At low pressure (200 MPa), the mineral assemblage as well as the mineral compositions of the natural basalt were reproduced at 1,000 °C and high water activity. The residual melt at these conditions is basaltic andesitic (55 wt% SiO2) with 5 wt% H2O. The evolution to more evolved magmas observed at Arenal occurred under fluid-saturated conditions but variable fluid compositions. At 1,000 °C and 200 MPa, a decrease of water content by approximately 1 wt% induces significant changes of the mineral assemblage from olivine + clinopyroxene + plagioclase (5 wt% H2O in the melt) to clinopyroxene + plagioclase + orthopyroxene (4 wt% H2O in the melt). Both assemblages are observed in crystal-rich basalt (15 vol%) and basaltic andesites. Experimental data indicate that the lack of orthopyroxene

  15. Complete Scene Recovery and Terrain Classification in Textured Terrain Meshes

    Directory of Open Access Journals (Sweden)

    Kyhyun Um

    2012-08-01

    Full Text Available Terrain classification allows a mobile robot to create an annotated map of its local environment from the three-dimensional (3D and two-dimensional (2D datasets collected by its array of sensors, including a GPS receiver, gyroscope, video camera, and range sensor. However, parts of objects that are outside the measurement range of the range sensor will not be detected. To overcome this problem, this paper describes an edge estimation method for complete scene recovery and complete terrain reconstruction. Here, the Gibbs-Markov random field is used to segment the ground from 2D videos and 3D point clouds. Further, a masking method is proposed to classify buildings and trees in a terrain mesh.

  16. PENENTUAN TAHANAN JENIS BATUAN ANDESIT MENGGUNAKAN METODE GEOLISTRIK KONFIGURASI SCHLUMBERGER (STUDI KASUS DESA POLOSIRI

    Directory of Open Access Journals (Sweden)

    - Munaji

    2013-11-01

    Full Text Available Telah dilakukan penelitian untuk menentukan nilai resistivitas dan kedalaman batuan andesit di Desa Polosiri. Prinsip kerja metode geolistrik adalah mempelajari aliran listrik di dalam bumi dan cara mendeteksi di permukaan bumi. Metode tahanan jenis didasari oleh hukum Ohm, untuk mengetahui jenis lapisan batuan didasarkan pada distribusi nilai resistivitas pada tiap lapisan. Variasi harga tahanan jenis akan didapatkan jika jarak masing-masing elektroda diubah, sesuai konfigurasi alat yang dipakai (konfigurasi Schlumberger. Data hasil pengukuran di lapangan berupa beda potensial dan arus yang dapat digunakan untuk menghitung resistivitas semu. Penelitian ini dilakukan sebanyak tiga lintasan. Data hasil pengukuran diolah menggunakan software IPI2Win. Berdasarkan hasil penelitian diperoleh bahwa batuan andesit di Desa Polisiri memiliki resistivitas 212 Ωm – 300 Ωm dengan kedalaman 1.3 m - 1.86 m.

  17. Processing Terrain Point Cloud Data

    KAUST Repository

    DeVore, Ronald

    2013-01-10

    Terrain point cloud data are typically acquired through some form of Light Detection And Ranging sensing. They form a rich resource that is important in a variety of applications including navigation, line of sight, and terrain visualization. Processing terrain data has not received the attention of other forms of surface reconstruction or of image processing. The goal of terrain data processing is to convert the point cloud into a succinct representation system that is amenable to the various application demands. The present paper presents a platform for terrain processing built on the following principles: (i) measuring distortion in the Hausdorff metric, which we argue is a good match for the application demands, (ii) a multiscale representation based on tree approximation using local polynomial fitting. The basic elements held in the nodes of the tree can be efficiently encoded, transmitted, visualized, and utilized for the various target applications. Several challenges emerge because of the variable resolution of the data, missing data, occlusions, and noise. Techniques for identifying and handling these challenges are developed. © 2013 Society for Industrial and Applied Mathematics.

  18. Isotopic composition of strontium in three basalt-andesite centers along the Lesser Antilles arc

    Science.gov (United States)

    Hedge, C.E.; Lewis, J.F.

    1971-01-01

    Si87/Sr86 ratios have been determined for lavas and py lastic rocks from three basalt-andesite centers along the Lesser Antilles arc-Mt. Misery on the island of St. Kitts, Soufriere on the island of St. Vincent, and Carriacou, an island of The Grenadines. The average Si87/Sr86 content of these rocks is 0.7038 for Mt. Misery, 0.7041 for Soufriere, and 0.7053 for Carriacou. All the Sr87/Sr86 values from each center are the same within analytical uncertainty (??0.0002). The constancy of strontium isotopic data within each center supports the hypothesis that basalts and andesites for each specific center investigated are generated from the same source - in agreement with petrographic and major- and minor-element data. Strontium isotopic compositions and elemental concentrations, particularly of strontium and nickel, indicate that this source was mantle peridotite and that the relationship between the respective basalts and andesites is probably fractional crystallization. ?? 1971 Springer-Verlag.

  19. Flow Computations on Imprecise Terrains

    CERN Document Server

    Driemel, Anne; Löffler, Maarten

    2011-01-01

    We study the computation of the flow of water on imprecise terrains. We consider two approaches to modeling flow on a terrain: one where water flows across the surface of a polyhedral terrain in the direction of steepest descent, and one where water only flows along the edges of a predefined graph, for example a grid or a triangulation. In both cases each vertex has an imprecise elevation, given by an interval of possible values, while its (x,y)-coordinates are fixed. For the first model, we show that the problem of deciding whether one vertex may be contained in the watershed of another is NP-hard. In contrast, for the second model we give a simple O(n log n) time algorithm to compute the minimal and the maximal watershed of a vertex, where n is the number of edges of the graph. On a grid model, we can compute the same in O(n) time.

  20. Complex Terrain and Wind Lidars

    DEFF Research Database (Denmark)

    Bingöl, Ferhat

    This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed...... in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar....... The SCADIS model worked better than the LINCOM model at the forest edge but the model reported closer results to the measurements at upwind than the downwind and this should be noted as a limitation of the model. As the general conclusion of the study, it was stated that the lidars can be used in complex...

  1. Application of the probabilistic model BET_UNREST during a volcanic unrest simulation exercise in Dominica, Lesser Antilles

    Science.gov (United States)

    Constantinescu, Robert; Robertson, Richard; Lindsay, Jan M.; Tonini, Roberto; Sandri, Laura; Rouwet, Dmitri; Smith, Patrick; Stewart, Roderick

    2016-11-01

    We report on the first "real-time" application of the BET_UNREST (Bayesian Event Tree for Volcanic Unrest) probabilistic model, during a VUELCO Simulation Exercise carried out on the island of Dominica, Lesser Antilles, in May 2015. Dominica has a concentration of nine potentially active volcanic centers and frequent volcanic earthquake swarms at shallow depths, intense geothermal activity, and recent phreatic explosions (1997) indicate the region is still active. The exercise scenario was developed in secret by a team of scientists from The University of the West Indies (Trinidad and Tobago) and University of Auckland (New Zealand). The simulated unrest activity was provided to the exercise's Scientific Team in three "phases" through exercise injects comprising processed monitoring data. We applied the newly created BET_UNREST model through its software implementation PyBetUnrest, to estimate the probabilities of having (i) unrest of (ii) magmatic, hydrothermal or tectonic origin, which may or may not lead to (iii) an eruption. The probabilities obtained for each simulated phase raised controversy and intense deliberations among the members of the Scientific Team. The results were often considered to be "too high" and were not included in any of the reports presented to ODM (Office for Disaster Management) revealing interesting crisis communication challenges. We concluded that the PyBetUnrest application itself was successful and brought the tool one step closer to a full implementation. However, as with any newly proposed method, it needs more testing, and in order to be able to use it in the future, we make a series of recommendations for future applications.

  2. Gene interactions constrain the course of evolution of phosphine resistance in the lesser grain borer, Rhyzopertha dominica.

    Science.gov (United States)

    Schlipalius, D I; Chen, W; Collins, P J; Nguyen, T; Reilly, P E B; Ebert, P R

    2008-05-01

    Phosphine, a widely used fumigant for the protection of stored grain from insect pests, kills organisms indirectly by inducing oxidative stress. High levels of heritable resistance to phosphine in the insect pest of stored grain, Rhyzopertha dominica have been detected in Asia, Australia and South America. In order to understand the evolution of phosphine resistance and to isolate the responsible genes, we have undertaken genetic linkage analysis of fully sensitive (QRD14), moderately resistant (QRD369) and highly resistant (QRD569) strains of R. dominica collected in Australia. We previously determined that two loci, rph1 and rph2, confer high-level resistance on strain QRD569, which was collected in 1997. We have now confirmed that rph1 is responsible for the moderate resistance of strain QRD369, which was collected in 1990, and is shared with a highly resistant strain from the same geographical region, QRD569. In contrast, rph2 by itself confers only very weak resistance, either as a heterozygote or as a homozygote and was not discovered in the field until weak resistance (probably due to rph1) had become ubiquitous. Thus, high-level resistance against phosphine has evolved via stepwise acquisition of resistance alleles, first at rph1 and thereafter at rph2. The semi-dominance of rph2 together with the synergistic interaction between rph1 and rph2 would have led to rapid selection for homozygosity. A lack of visible fitness cost associated with alleles at either locus suggests that the resistance phenotype will persist in the field.

  3. 2003-2004 Campaign GPS Geodetic Monitoring of Surface Deformation Proximal to Volcanic Centers, Commonwealth of Dominica, Lesser Antilles.

    Science.gov (United States)

    Davidson, R. T.; Turner, H. L.; Blessing, B. C.; Parra, J.; Fitzgibbon, K.; Jansma, P.; Mattioli, G.

    2004-12-01

    The Commonwealth of Dominica, located midway along the Lesser Antilles island arc, is home to several (at least eight) potentially active volcanic centers. Spurred by recent seismic crises on the island - in the south from 1998-2000 and in the north in 2003 - twelve GPS monuments were installed in two field campaigns in 2001 and 2003. All twelve sites, along with five of six newly installed sites, were occupied continuously for ~2.5 or more UTC days in 2004 using Ashtech Z-12 dual-frequency, code-phase receivers and choke ring antenna to assess the highly complex and possibly interconnected volcanic systems of Dominica. We examine data from the 2003-2004 epochs because of the highly variable, shallow seismicity preceding this period. This way one can potentially isolate the changes that occurred without the data from previous observations influencing the results. Although only two epochs have been included, data quality and reliability can be established from sites distant from volcanic centers, as such sites show consistent velocities from all three epochs of observation over the 2001-2004 period. Between 2003 and 2004, multiple sites show velocities that are inconsistent with a simple tectonic interpretation of elastic strain accumulation along the plate interface. Sites located in the vicinity of the volcanic centers in the south central part of the island are moving faster than the 3 epoch 2001-2004 average of the velocities, which is approximately 7mm/year. The four sites at which greater movement has been noted have velocities ranging from approximately 10 to 27 mm/year. We note that the largest surface deformation signal is seen in the south during the same period when the shallow seismicity was at a maximum in the north of the island. While the spatial distribution of sites remains sparse and the velocities relatively imprecise, the preliminary results may indicate shallow magmatic emplacement, geothermal fluctuations, or structural instability in that part

  4. Dispersion scenarios over complex terrain

    DEFF Research Database (Denmark)

    Thykier-Nielsen, S.; Mikkelsen, T.; Moreno, J.

    1993-01-01

    A presentation of preliminary results from a real-time simulation of full-scale dispersion experiments carried out over complex terrain in Northern Spain is given. Actual wind and turbulence measurements as observed during the experiments were analysed and used as input data for a series of simul......A presentation of preliminary results from a real-time simulation of full-scale dispersion experiments carried out over complex terrain in Northern Spain is given. Actual wind and turbulence measurements as observed during the experiments were analysed and used as input data for a series...... are suitable for subsequent comparison with observed mean dispersion data when they become available....

  5. Dispersion scenarios over complex terrain

    DEFF Research Database (Denmark)

    Thykier-Nielsen, S.; Mikkelsen, T.; Moreno, J.

    1993-01-01

    A presentation of preliminary results from a real-time simulation of full-scale dispersion experiments carried out over complex terrain in Northern Spain is given. Actual wind and turbulence measurements as observed during the experiments were analysed and used as input data for a series of simul......A presentation of preliminary results from a real-time simulation of full-scale dispersion experiments carried out over complex terrain in Northern Spain is given. Actual wind and turbulence measurements as observed during the experiments were analysed and used as input data for a series...

  6. Complex terrain and wind lidars

    Energy Technology Data Exchange (ETDEWEB)

    Bingoel, F.

    2009-08-15

    This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar can be of the order of 3-4% in moderately-complex terrain and up to 10% in complex terrain. The findings were based on experiments involving collocated lidars and meteorological masts, together with flow calculations over the same terrains. The lidar performance was also simulated with the commercial software WAsP Engineering 2.0 and was well predicted except for some sectors where the terrain is particularly steep. Subsequently, two experiments were performed in forested areas; where the measurements are recorded at a location deep-in forest and at the forest edge. Both sites were modelled with flow models and the comparison of the measurement data with the flow model outputs showed that the mean wind speed calculated by LINCOM model was only reliable between 1 and 2 tree height (h) above canopy. The SCADIS model reported better correlation with the measurements in forest up to approx6h. At the forest edge, LINCOM model was used by allocating a slope half-in half out of the forest based on the suggestions of previous studies. The optimum slope angle was reported as 17 deg.. Thus, a suggestion was made to use WAsP Engineering 2.0 for forest edge modelling with known limitations and the applied method. The SCADIS model worked better than the LINCOM model at the forest edge but the model reported closer results to the measurements at upwind than the downwind and this should be

  7. High-Mg# andesitic lavas of the Shisheisky Complex, Northern Kamchatka: implications for primitive calc-alkaline magmatism

    Science.gov (United States)

    Bryant, J. A.; Yogodzinski, G. M.; Churikova, T. G.

    2011-05-01

    Primitive arc magmatism and mantle wedge processes are investigated through a petrologic and geochemical study of high-Mg# (Mg/Mg + Fe > 0.65) basalts, basaltic andesites and andesites from the Kurile-Kamchatka subduction system. Primitive andesitic samples are from the Shisheisky Complex, a field of Quaternary-age, monogenetic cones located in the Aleutian-Kamchatka junction, north of Shiveluch Volcano, the northernmost active composite volcano in Kamchatka. The Shisheisky lavas have Mg# of 0.66-0.73 at intermediate SiO2 (54-58 wt%) with low CaO (3.0 wt%) and K2O (>1.0 wt%). Olivine phenocryst core compositions of Fo90 appear to be in equilibrium with whole-rock `melts', consistent with the sparsely phyric nature of the lavas. Compared to the Shisheisky andesites, primitive basalts from the region (Kuriles, Tolbachik, Kharchinsky) have higher CaO (>9.9 wt%) and CaO/Al2O3 (>0.60), and lower whole-rock Na2O (andesites. The absence of plagioclase phenocrysts from the primitive andesitic lavas contrasts the plagioclase-phyric basalts, indicating relatively high pre-eruptive water contents for the primitive andesitic magmas compared to basalts. Estimated temperature and water contents for primitive basaltic andesites and andesites are 984-1,143°C and 4-7 wt% H2O. For primitive basalts they are 1,149-1,227°C and 2 wt% H2O. Petrographic and mineral compositions suggest that the primitive andesitic lavas were liquids in equilibrium with mantle peridotite and were not produced by mixing between basalts and felsic crustal melts, contamination by xenocrystic olivine, or crystal fractionation of basalt. Key geochemical features of the Shisheisky primitive lavas (high Ni/MgO, Na2O, Ni/Yb and Mg# at intermediate SiO2) combined with the location of the volcanic field above the edge of the subducting Pacific Plate support a genetic model that involves melting of eclogite or pyroxenite at or near the surface of the subducting plate, followed by interaction of that melt with

  8. Preeruption conditions and timing of dacite-andesite magma mixing in the 2.2 ka eruption at Mount Rainier

    Science.gov (United States)

    Venezky, D. Y.; Rutherford, M. J.

    1997-01-01

    Analytical, field, and experimental evidence demonstrate that the Mount Rainier tephra layer C (2.2 ka) preserves a magma mixing event between an andesitic magma (whole rock SiO2 content of 57-60 wt %) and a dacitic magma (whole rock SiO2 content of 65±1 wt %). The end-member andesite (a mix of an injected and chamber andesite) and dacite can be characterized on the basis of the homogeneity of the matrix glass and phenocryst rim compositions. Many pumices, however, contain mixtures of the end-members. The end-member dacite contains a microlite-free matrix glass with 74-77 wt % SiO2, orthopyroxene rims of Mg57-64, clinopyroxene rims of Mg66-74, and plagioclase rim anorthite contents of An45-65. The temperature and oxygen fugacity, from Fe-Ti oxide compositions, are 930±10°C and 0.5-0.75 log units above NNO. The mixed andesite contains Mg73-84 orthopyroxene rims, Mg73-78 clinopyroxene rims, An78-84 plagioclase rims, and Mg67-74 amphibole rims. The temperature from Fe-Ti oxides, hornblendeplagioclase, and two-pyroxene geothermometry is 1060±15°C, and the oxygen fugacity is approximately one log unit above NNO for the injected andesite. The chamber andesite is estimated to be a magma with a ˜64-65 wt % SiO2 melt at 980°C and a NNO oxygen fugacity. We conclude that the andesitic and dacitic magmas are from separate magma storage regions (at >7 km and ˜2.4 km) due to differences in the bimodal whole rock, matrix glass, and phenocryst compositions and the presence or absence of stable hornblende. The time involved from the mixing event through the eruption is limited to a period of 4-5 days based on Fe-Ti oxide reequilibration, phenocryst growth rates, and hornblende breakdown. The eruption sequence is interpreted as having been initiated by an injection of the 1060±15°C andesitic magma into the ˜980°C (>7 km) andesite storage region. The mixed andesitic magma then intersected a shallow, ˜2.4 km, dacitic storage system on its way toward the surface. The

  9. Primitive, high-Mg basaltic andesites: direct melts of the shallow, hot, wet mantle

    Science.gov (United States)

    Andrews, A.; Grove, T. L.

    2013-12-01

    Direct mantle melts are rare in subduction zone settings. Such melts are identified by Mg #s (Mg # = Mg / (Mg+Fe)) greater than ~0.73, indicating chemical equilibrium with Fo90 mantle olivine. Most of these primitive arc melts are basaltic, characterized by SiO2 contents of ~48-50 wt % and MgO contents ranging from 8-10 wt %. However, primitive basaltic andesites with mantle-equilibrated Mg #s have also been found at subduction zones worldwide. These basaltic andesites have higher SiO2 contents (53-58 wt %) than typical primitive basalts as well as high MgO (8-10 wt %). Because these rocks have high SiO2 contents and yet retain evidence for chemical equilibrium with the mantle (Mg #s), their petrogenesis has sparked intense debate as researchers have tried to discern how these samples fit into the paradigm of mantle melting at subduction zones. Through an understanding of the conditions and processes that produce the SiO2 enrichment in these rocks, we also aim to understand the role of these melts in producing the observed andesitic compositional characteristics of the continental crust. To understand the petrogenesis of primitive, high-Mg basaltic andesites, this study investigates the experimental melts of undepleted mantle peridotite plus a slab component (Na-2O + K2O) from 1,205-1,470°C at 1.0-2.0 GPa under water-undersaturated conditions (0-5 wt % H2O). At 1.0 and 1.2 GPa, the experimental melts reproduce the compositions of natural primitive, high-Mg basaltic andesites in all major elements (SiO2, TiO2, Al2O3, FeO, MnO, MgO, and Na2O+K2O) except CaO. CaO contents are higher than the range of the natural samples by ~2 wt % at the highest silica contents of the experiments (54-56 wt% SiO2). This suggests that at 1.0-1.2 GPa, a higher percent of melting (30-35 %) with 3-5 wt % H2O is required to drive the chemical compositions of the experiments toward the representative compositions of the natural rocks. The experimental melts also show that mantle-wall rock

  10. Origin of primitive andesites by melt-rock reaction in the sub-arc mantle (Invited)

    Science.gov (United States)

    Rapp, R. P.

    2009-12-01

    The genetic relationship between primitive granitoids, including high-Mg andesites (HMAs) and bajaites, and primary granitoids, or "pristine" adakites, has been vigorously debated since Defant and Drummond (1991; henceforth D&D) first applied the term "adakite" to refer to Cenozoic arc magmas (andesites and dacites) "associated with young subducting lithosphere", with low Y and Yb, low high-field strength elements (HFSEs), high Sr, and high Sr/Y and (La/Yb)N ratios "relative to island arc andesite-dacite-rhyolite". These characteristics were attributed to an origin for adakites by partial melting of basaltic crust within the subducting slab (hence "slab melts"). That such a process can produce melts with the characteristics described by D&D has since been largely confirmed by dehydration melting experiments on hydrous metabasalt at ~1-4 GPa. Attention was also drawn to the geochemical similarities between "adakites" and large-ion lithophile element (LILE)-enriched, high-field strength element (HFSE) depleted magnesian andesites (HMAs) from Adak Island in the western Aleutians, first described by Kay (1978), implying a genetic relationship between primary granitoid (adakites) formed by partial melting of basaltic ocean crust in the subducting slab, transformed to garnet-amphibolite or eclogite, and primitive magnesian andesites (HMAs) with high Mg-numbers (Mg# = molar Mg/(Mg+Fe)x100) and high concentrations of Ni and Cr. What then is the true origin of these enigmatic arc magmas, with both crustal and mantle, derivative and primitive, geochemical signatures? Kay (1978) suggested a "hybrid" model, in which "hydrous melting of eclogite (slab melting) results in a small volume of dacitic melt ("pristine adakite"), which rises into the hotter overlying peridotite wedge and equilibrates with olivine and orthopyroxene, reacting with olivine until it becomes andesitic". In this paper, I will discuss the results of melt-rock reaction experiments modelling this peridotite

  11. An automated system for terrain database construction

    Science.gov (United States)

    Johnson, L. F.; Fretz, R. K.; Logan, T. L.; Bryant, N. A.

    1987-01-01

    An automated Terrain Database Preparation System (TDPS) for the construction and editing of terrain databases used in computerized wargaming simulation exercises has been developed. The TDPS system operates under the TAE executive, and it integrates VICAR/IBIS image processing and Geographic Information System software with CAD/CAM data capture and editing capabilities. The terrain database includes such features as roads, rivers, vegetation, and terrain roughness.

  12. Effect of five diatomaceous earth formulations against Tribolium castaneum (Coleoptera: Tenebrionidae),Oryzaephilus surinamensis (Coleoptera: Silvanidae) and Rhyzopertha dominica (Coleoptera: Bostrychidae)

    Institute of Scientific and Technical Information of China (English)

    MASUMEH ZIAEE; ADEL KHASHAVEH

    2007-01-01

    Laboratory bioassays were conducted to determine the effect of food source on the survival of Tribolium castaneum Herbst, Oryzaephilus surinamensis L. and Rhyzopertha dominica F., after exposure to five diatomaceous earth (DE) formulations: Protect-It(R),Insecto(R), Perma-GuardTM, Dryacide(R) and SilicoSec(R). Adults of these species were exposed to DEs at the rate of 0.5 mg/cm2 for 1 day on filter paper inside plastic Petri dishes. After exposure,the initial mortality was counted and live individuals of the three species were held for a week in glass vials containing 50 mg wheat flour, rice and whole wheat, respectively. In the second experiment, after 1 day exposure to DEs, beetles were transferred to Petri dishes without food and held for a week to determine if the presence of food source would decrease the mortality of beetles. Experiments were carried out at 27℃ and 55% RH in the dark. The initial morality in both of the experiments reached 100% for the three species exposed to Protect-It(R) and in the case orR. dominica and O. surinamensis exposed to Dryacide(R). In contrast, low level of mortality (< 10%) was observed for T. castaneum exposed to Perma-GuardTM and Insecto(R). The mortality after the post-treatment period on food was decreased for the three species exposed to Perma-GuardTM and in the case of T. castaneum and R. dominica exposed to Insecto(R) and SilicoSec(R). Adults of O. surinamensis were the most susceptible followed by R. dominica and 100% adult mortality was obtained, whereas T. castaneum were the least susceptible beetles to DEs. Protect-It(R) and Dryacide(R) were the most efficient DE formulations and can be used effectively in a stored grain integrated pest management program.

  13. Efficacies of spinosad and a combination of chlorpyrifos-methyl and deltamethrin against phosphine-resistant Rhyzopertha dominica (Coleoptera: Bostrichidae) and Tribolium castaneum (Coleoptera: Tenebrionidae) on wheat.

    Science.gov (United States)

    Bajracharya, N S; Opit, George P; Talley, J; Jones, C L

    2013-10-01

    Highly phosphine-resistant populations of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) have recently been found in Oklahoma grain storage facilities. These findings necessitate development of a phosphine resistance management strategy to ensure continued effective use of phosphine. Therefore, we investigated the efficacies of two grain insecticides, namely, spinosad applied at label rate of 1 ppm and a mixture of chlorpyrifos-methyl and deltamethrin applied at label rates of 3 and 0.5 ppm, respectively, against highly phosphine-resistant R. dominica and T. castaneum. Adult mortality and progeny production suppression of spinosad- or chlorpyrifos-methyl + deltamethrin mixture-treated wheat that had been stored for 2, 84, 168, 252, and 336 d posttreatment were assessed. We found that both spinosad and chlorpyrifos-methyl + deltamethrin were effective against phosphine-resistant R. dominica and caused 83-100% mortality and also caused total progeny production suppression for all storage periods. Spinosad was not effective against phosphine-resistant T. castaneum; the highest mortality observed was only 3% for all the storage periods. Chlorpyrifos-methyl + deltamethrin was effective against phosphine-resistant T. castaneum only in treated wheat stored for 2 and 84 d, where it caused 93-99% mortality. However, chlorpyrifos-methyl + deltamethrin was effective and achieved total suppression of progeny production in T. castaneum for all the storage periods. Spinosad was not as effective as chlorpyrifos-methyl + deltamethrin mixture at suppressing progeny production of phosphine-resistant T. castaneum. These two insecticides can be used in a phosphine resistance management strategy for R. dominica and T. castaneum in the United States.

  14. Susceptibility of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Sitophilus oryzae (L.) (Coleoptera: Curculionidae) to Spinosad (Tracer®) as a Eco-friendly Biopesticide

    OpenAIRE

    Reza Sadeghi; Asgar Ebadollahi

    2015-01-01

    Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) are internal feeder of various stored grains and introducted as major stored product insect pests. Due to the resistance by insect pests and negative effects of synthetic pesticides to the environment, it is necessary to use novel and suitable compounds in insect pest’s management. Spinosad is a bio-insecticide that is derived from fermentation of a bacterium Saccharopolyspora spinosa Mertz and Yao. In the present study, the toxicity of Tra...

  15. Utilização da fosfina em combinação com o dióxido de carbono no controle do Rhyzopertha dominica (f. Combination of phosphine and carbon dioxide on the control of Rhyzopertha dominica (f.

    Directory of Open Access Journals (Sweden)

    ANA PAULA MARTINAZZO

    2000-06-01

    Full Text Available Objetivou-se avaliar o efeito da utilização de fosfina, associada a uma atmosfera rica em dióxido de carbono (CO2, no controle efetivo do inseto Rhyzopertha dominica (F. em todas as suas fases de desenvolvimento. Para isso, foram realizadas fumigações com atmosfera sintética contendo 21% de CO2 e 79% de N2 associada a níveis reduzidos de fosfina (0,25, 0,50 e 0,75 g m-3. Para posterior comparação dos resultados, foram realizados dois tratamentos com ar ambiente associado às dosagens de zero e 1,00 g m-3 de fosfina. Todos os tratamentos foram realizados em três períodos de exposição (24, 72 e 120 horas, à temperatura de 29°C e umidade relativa de 60%. A análise dos resultados permitiu concluir que o aumento no período de exposição resultou no aumento da eficácia dos tratamentos em atmosferas sintética e ambiente. O controle efetivo de todas as fases do inseto foi obtido, em geral, com 0,50 e 0,75 g m-3 de fosfina + CO2, em período de exposição de 120 horas. Ovos e adultos foram as fases mais suscetíveis, e pupa, a mais resistente.The objective of this research was to evaluate the effect of low levels of phosphine associated with atmospheres containing high levels of carbon dioxide (CO2 on the effective control of all life stages of the insect Rhyzopertha dominica (F.. To this purpose, fumigations were carried out using a synthetic atmosphere containing 21% of CO2 and 79% of N2 associated with the following levels of phosphine: 0.25, 0.50, and 0.75 g m-3. Results were compared with mortality rates achieved with ambient air containing zero and 1.00 g m-3 of phosphine. All tests were carried out using three levels of exposure time (24, 72, and 120 hours, and one level of temperature and relative humidity, 29°C and 60%, respectively. Analyses of the results indicated that increasing the exposure time resulted in an increase in mortality rates in all tests conducted with synthetic and ambient air. Effective control of all

  16. Andesite petrogenesis in a hybrid arc-rift setting: the Western Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Gómez-Tuena, A.; Vázquez-Duarte, A.; Díaz-Bravo, B.; Mori, L.

    2011-12-01

    The western sector of the Mexican subduction zone is characterized by the steep subduction of one of the youngest slabs on the planet (Rivera plate), and by the existence of a continental rift at ~230 km to the north from the trench (the so-called Tepic-Zacoalco rift, TZR), under which the subducted slab is either extremely deep or even absent (>250 km). The volcanic front is located at ~170 km from the trench and contains abundant potassic-alkaline lamprophyres with strong subduction (Ba/Ta= 1600-6000) and garnet signatures (Gd/Yb= 2-8), that have been recently interpreted as influenced by deep K2O-rich slab melts or supercritical fluids (Gómez-Tuena et al., 2011, GCA). In contrast, the most mafic rocks within the TZR are high-Nb, intraplate-like basalts that appear to derive from low extents of melting of a dryer (Ba/Ta= 800-60) and shallower (Gd/Yb= 2-2.5) mantle source. Even though a simple transition from an arc environment to an extensional tectonic regime is apparent when only the most primitive volcanic rocks are taken into account, the scenario becomes more complicated since at least five stratovolcanoes have been erupting typical arc andesites within the TZR over the last million years (San Juan, Sanganguey, Tepetiltic, Ceboruco and Tequila). Surprisingly, true calc-alkaline basalts that could be parental to andesites have not been found, indicating that andesites may have a direct mantle origin. Indeed, mayor and trace element compositions of volcanic rocks from western Mexico arrange in discrete suites with linear trends that are indicative of mixing, but they form sub-parallel arrays that do not converge to a common primitive basaltic melt, and often follow diverging trends in trace element-ratio plots. Melt-crust interactions likely occurred during magma ascent, since the volcanic rocks frequently include xenoliths and disequilibrium textures, but correlations among isotopic compositions and indexes of fractionation are not clearly observed in the

  17. Mantle Origin of Silicic Calc-alkaline Basalts to Andesites in the Central Mexican Volcanic Belt

    Science.gov (United States)

    Straub, S. M.; Zellmer, G. F.; Gómez-Tuena, A.; Stuart, F.; Espinasa-Perena, R.; Cai, Y.

    2011-12-01

    The Quaternary central Mexican Volcanic Belt, constructed on ~50 km thick continental crust, erupts a broad spectrum of basaltic to dacitic calc-alkaline magmas with the arc-typical high ratios of large-ion lithophile to high-field strength elements. In order to understand their genesis, we investigated high-Mg# olivine-phyric calc-alkaline basalts to andesites from Holocene monogenetic volcanoes Tuxtepec (50.2 wt% SiO2; 9.7 wt% MgO), Yecahuazac (53.1;8.0), Suchiooc Cone (53.2;9.2), Guespalapa (54.4-61.2;5.3-7.9) and Cuatepel (55.6-58.9;5.4-7.5), and as well as one basaltic andesite from composite volcano Popocateptl (56.7;6.9). The high 3He/4He (7.3 ± 0.3 Ra; n=16) of olivine phenocrysts that crystallize at upper crustal levels, and the limited range of Sr-Nd-Hf isotope ratios preclude any significant crustal contamination of these magmas. Moreover, small, but significant differences in Sr-Nd-Hf isotope ratios and the variations of olivine phenocrysts in the Fo-Ni space conclusively rule out that these magmas were related through fractional crystallization. Consequently, the basaltic to andesitic magmas must originate from the sub-arc mantle. Building on the high-Ni content of the olivines that by far exceed Ni abundances of olivines in partial melts of peridotite, we propose that the subarc MVB mantle contains segregations of silica-excess and silica-deficient 'reaction pyroxenites' that formed through infiltration of highly reactive silicic fluids or melts from slab. Upon melting, the pyroxenites produce dacitic and basaltic initial melts, respectively, that mix in variable proportions during ascent through mantle and crust. This genetic model links the silica enrichment of the arc magmas directly to the silica flux from slab, with no requirement for any significant melt silica increase in the overlying crust.

  18. Spectra of Velocity components over Complex Terrain

    DEFF Research Database (Denmark)

    Panofsky, H. A.; Larko, D.; Lipschut, R.

    1982-01-01

    Spectra have been measured over a variety of types of complex terrain: on tops of hills and escarpments, over land downstream of a water surface, and over rolling terrain. Differences between spectra over many types of complex terrain, and over uniform terrain, can be explained by these hypotheses...... is horizontal, and decrease when the flow is uphill, for the longitudinal velocity component only. Since vertical-velocity spectra contain relatively less low wavenumber energy than horizontal-velocity spectra, energetic vertical-velocity fluctuations tend to be in equilibrium with local terrain....

  19. Prediction models in complex terrain

    DEFF Research Database (Denmark)

    Marti, I.; Nielsen, Torben Skov; Madsen, Henrik

    2001-01-01

    are calculated using on-line measurements of power production as well as HIRLAM predictions as input thus taking advantage of the auto-correlation, which is present in the power production for shorter pediction horizons. Statistical models are used to discribe the relationship between observed energy production......The objective of the work is to investigatethe performance of HIRLAM in complex terrain when used as input to energy production forecasting models, and to develop a statistical model to adapt HIRLAM prediction to the wind farm. The features of the terrain, specially the topography, influence...... and HIRLAM predictions. The statistical models belong to the class of conditional parametric models. The models are estimated using local polynomial regression, but the estimation method is here extended to be adaptive in order to allow for slow changes in the system e.g. caused by the annual variations...

  20. The role of polybaric crystallization in genesis of andesitic magmas: Phase equilibria simulations of the Bezymianny volcanic subseries

    Science.gov (United States)

    Almeev, Renat R.; Ariskin, Alexei A.; Kimura, Jun-Ichi; Barmina, Galina S.

    2013-08-01

    Using the updated COMAGMAT model, the crystallization sequences of a Bezymianny Volcano basaltic andesite (Kamchatka, Russia) are simulated in a wide range of thermodynamic conditions (P-T-fO2) as a function of H2O concentration. Comparison of the modeled liquid lines of descent with petrochemical trends of the volcanic suite indicates the parental melts contain 1.5-2 wt.% H2O stored under 490-520 MPa pressure in the magma plumbing system beneath Bezymianny Volcano. The initial magma originates as a result of the polybaric evolution of mantle-derived high-Mg basaltic magmas of the adjacent Kliuchevskoi Volcano. The subsequent evolution of derivative hydrous and alumina-rich basaltic andesite magmas may proceed under polybaric conditions with an average decompression of ~ 12 MPa per 1% of crystallization. In the course of polybaric crystallization, compositions of pyroxene-bearing andesites can be numerically reproduced and the modeled liquid compositions follow the natural liquid line of descent. However, hornblende-bearing magmas cannot be produced as a result of continued crystallization from parental basaltic andesite through the stage of pyroxene-bearing andesite formation. They require high water contents and high pressures of crystallization. In this case, liquid composition should deviate from the chemical trend defined by the whole rock compositions.

  1. Avaliação de inseticidas no controle de Sitophilus oryzae (Linnaeus (Coleoptera, Curculionidae e Rhyzopertha dominica (Fabricius (Coleoptera, Bostrichidae em trigo armazenado Efficacy of insecticides to control Sitophilus oryzae (Linnaeus (Coleoptera, Curculionidae and Rhyzopertha dominica (Fabricius (Coleoptera, Bostrichidae in stored wheat

    Directory of Open Access Journals (Sweden)

    Rui S. Furiatti

    1999-03-01

    Full Text Available The efficiency of insecticides against Sitophilus oryzae (Linnaeus, 1763 (Coleoptera, Curculionidae and Rhyzopertha dominica (Fabricius, 1792 (Coleoptera, Bostrichidae was determined exposing them to treated wheat in laboratory. Each plot, which was composed by 1.2 kg of wheat grain, was treated with 5 ml of the concentration/kg of wheat using a propelling air atomizer. Fifteen days after treatment 50 g samples of the grain were taken, from each plot, placed in plastic jars into which 10 adult insects of each species were released. This was repeated every 30 days until 165 days after treatment. The number of dead insects was counted 15 days after each infestation thus the evaluations were made at 30, 60, 90, 120, 150 and 180 days after the insecticide application. Esfenvalerate+fenitrothion+pyperonil butoxide (0,375+7,5+3,0 and 0,5+10,0+4,0 g a.i./t, fenitrothion+esfen-valerate (7,5+0,375 and 10,0+0,375 g a.i./t, fenitrothion+synergised deltamethrin (7,5+0,375 g a.i./t and fenitrothion (7,5 g a.i./t were effective against Sitophilus oryzae until 180 days after treatment. Esfenvalerate+fenitrothion+pyperonil butoxide (0,5+10,0+4,0 g a.i./t, fenitrothion+esfenvalerate (7,5+0,375 and 10,0+0,375 g a.i./t, fenitrothion+synergised deltamethrin (7,5+0,375 g a.i./t were effective against R. dominica until 180 days after treatment. Synergised deltamethrin (0,375 g a.i./t was effective against S. oryzae until 150 days and against R. dominica until 120 days after treatment. Esfenvalerate (0,5 g a.i./t was ineffective against S. oryzae and effective until 60 days after treatment against R. dominica. Fenitrothion (7,5 g a.i./t was ineffective against R. dominica. The use of mixtures of organophosphorus plus pyrethroids were more effective against S. oryzae and R. dominica when compared with these insecticides used alone.

  2. Antisana volcano: A representative andesitic volcano of the eastern cordillera of Ecuador: Petrography, chemistry, tephra and glacial stratigraphy

    Science.gov (United States)

    Hall, Minard L.; Mothes, Patricia A.; Samaniego, Pablo; Militzer, Annemarie; Beate, Bernardo; Ramón, Patricio; Robin, Claude

    2017-01-01

    Antisana volcano is representative of many active andesitic strato-volcanoes of Pleistocene age in Ecuador's Eastern Cordillera. This study represents the first modern geological and volcanological investigation of Antisana since the late 1890's; it also summarizes the present geochemical understanding of its genesis. The volcano's development includes the formation and destruction of two older edifices (Antisana I and II) during some 400 + ka. Antisana II suffered a sector collapse about 15,000 years ago which was followed by the birth and growth of Antisana III. During its short life Antisana III has generated ≥50 eruptions of small to medium intensity, often associated with andesitic to dacitic lava flows and tephra, as well as with late Pleistocene and Holocene glacial advances. Throughout its long history Antisana's lavas have been characterized by a persistent mineral assemblage, consisting of 30-40 vol% phenocrysts of plagioclase, both clino- and orthopyroxene, and Fe-Ti oxides, with rare occurrences of olivine or amphibole, frequently in a microcrystalline to glassy matrix. This uniformity occurs despite the magma's progressive chemical evolution over ≥400 ka from early basic andesites (53-58 wt% SiO2) to intermediate and Si-rich andesites (58-62% SiO2), and recently to dacites (63-67% SiO2). Chemical diagrams suggest that crystal fractionation was the most likely magmatic process of evolution. The exception to this slowly evolving history was the short-lived emission at ∼210 ka of the Cuyuja lavas from Antisana II that generated a 73 km long andesitic lava flow. Contrasting with Antisana's general magmatic trend, Cuyuja lava (∼11 km3) is a high-Mg andesite with unusually high concentrations of incompatible elements. Antisana developed within the Chacana caldera complex, a large active siliceous center that began ∼3 Ma ago, however its lavas are chemically distinct from coeval lavas of Chacana.

  3. Thermal properties of andesite from Popocatepetl and Volcán de Colima, México.

    Science.gov (United States)

    Cardenas-Sanchez, Enrique; De la Cruz-Reina, Servando; Varley, Nick

    2015-04-01

    The thermal conductivity (K), specific heat (Cp) and the coefficient of heat transfer surface (H) are the basic parameters to describe the process of cooling a volcanic rock fragment released in an explosive event. The analysis of the cooling process by conduction, convection and radiation of heat in volcanic rock fragments, has been limited to basalts, and various minerals such as olivine, pyroxene, quartz, etc. (Miao & Chen, 2014; Branlund & Hofmeister, 2012; Romine et al, 2012;. Schön, 2011; Stroberg et al, 2010;. Schatz & Simmons, 1972). There are no detailed studies on the thermal properties of the andesites, abundant in continental stratovolcanoes, and particularly susceptible from lava domes with frequent destruction processes, such as Popocatepetl and Volcan de Colima. Previously, we developed an algorithm for calculation of the grain-size distribution, degree of fragmentation, the thermal energy released and its possible correlation with Volcanic Explosive Index (VEI) from the cooling curves of fragments from vulcanian and strombolian explosions. These curves were obtained from sequences of time over incandescent deposits recorded at selected pixel thermal images of vulcanian activity in the Popocatepetl and Volcan de Colima, Mexico. However, the model was limited by the lack of thermal parameters of the andesites, forcing a first approximation using basalts data. We present a simple model for the cooling process using andesites samples from Popocatépetl and Volcan de Colima. First, the samples were subjected to a rounding process to minimize surface effects. Then, heated to 800 ° C were extracted from the muffle and cooling rate is measured. The thermal conductivity and coefficient of surface heat are determined using a thermal camera and three thermocouples embedded at various depths within the sample. An inversion method was implemented to determine the thermal properties parameters , by comparing the observed data regarding cooling model for a solid

  4. Sulfur isotope fractionation between fluid and andesitic melt: An experimental study

    Science.gov (United States)

    Fiege, Adrian; Holtz, François; Shimizu, Nobumichi; Mandeville, Charles W.; Behrens, Harald; Knipping, Jaayke L.

    2014-01-01

    Glasses produced from decompression experiments conducted by Fiege et al. (2014a) were used to investigate the fractionation of sulfur isotopes between fluid and andesitic melt upon magma degassing. Starting materials were synthetic glasses with a composition close to a Krakatau dacitic andesite. The glasses contained 4.55–7.95 wt% H2O, ∼140 to 2700 ppm sulfur (S), and 0–1000 ppm chlorine (Cl). The experiments were carried out in internally heated pressure vessels (IHPV) at 1030 °C and oxygen fugacities (fO2) ranging from QFM+0.8 log units up to QFM+4.2 log units (QFM: quartz–fayalite–magnetite buffer). The decompression experiments were conducted by releasing pressure (P) continuously from ∼400 MPa to final P of 150, 100, 70 and 30 MPa. The decompression rate (r) ranged from 0.01 to 0.17 MPa/s. The samples were annealed for 0–72 h (annealing time, tA) at the final P and quenched rapidly from 1030 °C to room temperature (T).The decompression led to the formation of a S-bearing aqueous fluid phase due to the relatively large fluid–melt partitioning coefficients of S. Secondary ion mass spectrometry (SIMS) was used to determine the isotopic composition of the glasses before and after decompression. Mass balance calculations were applied to estimate the gas–melt S isotope fractionation factor αg-m.No detectable effect of r and tA on αg-m was observed. However, SIMS data revealed a remarkable increase of αg-m from ∼0.9985 ± 0.0007 at >QFM+3 to ∼1.0042 ± 0.0042 at ∼QFM+1. Noteworthy, the isotopic fractionation at reducing conditions was about an order of magnitude larger than predicted by previous works. Based on our experimental results and on previous findings for S speciation in fluid and silicate melt a new model predicting the effect of fO2 on αg-m (or Δ34Sg–m) in andesitic systems at 1030 °C is proposed. Our experimental results as well as our modeling are of high importance for the interpretation of S isotope

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

    Science.gov (United States)

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

    2016-04-01

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

  6. Silica-enriched mantle sources of subalkaline picrite-boninite-andesite island arc magmas

    Science.gov (United States)

    Bénard, A.; Arculus, R. J.; Nebel, O.; Ionov, D. A.; McAlpine, S. R. B.

    2017-02-01

    compositions extracted from these hybrid sources are higher in normative quartz and hypersthene (i.e., they have a more silica-saturated character) in comparison with basalts derived from prior melt-depleted asthenospheric mantle beneath ridges. These primary arc melts range from silica-rich picrite to boninite and high-Mg basaltic andesite along a residual spinel harzburgite cotectic. Silica enrichment in the mantle sources of arc-related, subalkaline picrite-boninite-andesite suites coupled with the amount of water and depth of melting, are important for the formation of medium-Fe ('calc-alkaline') andesite-dacite-rhyolite suites, key lithologies forming the continental crust.

  7. Using mineral geochemistry to decipher slab, mantle, and crustal input in the generation of high-Mg andesites and basaltic andesites from the northern Cascade Arc

    Science.gov (United States)

    Sas, May; DeBari, Susan; Clynne, Michael A.; Rusk, Brian G.

    2017-01-01

    To better understand the role of slab melt in the petrogenesis of North Cascades magmas, this study focuses on petrogenesis of high-Mg lavas from the two northernmost active volcanoes in Washington. High-Mg andesites (HMA) and basaltic andesites (HMBA) in the Cascade Arc have high Mg# [molar Mg/(Mg+Fe2+)] relative to their SiO2 contents, elevated Nd/Yb, and are Ni- and Cr-enriched. The rock units examined here include the Tarn Plateau HMBA (51.8–54.0 wt% SiO2, Mg# 68–70) and Glacier Creek HMA (58.3–58.7 wt% SiO2, Mg# 63–64) from the Mount Baker Volcanic Field, and the Lightning Creek HMBA (54.8–54.6 SiO2, Mg# 69–73) from Glacier Peak. This study combines major and trace element compositions of minerals and whole rocks to test several petrogenetic hypotheses and to determine which, if any, are applicable to North Cascades HMA and HMBA. In the Tarn Plateau HMBA, rare earth element (REE) equilibrium liquids calculated from clinopyroxene compositions have high Nd/Yb that positively correlates with Mg#. This correlation suggests an origin similar to that proposed for Aleutian adakites, where intermediate, high Nd/Yb slab-derived melts interact with the overlying mantle to become Mg-rich, and subsequently mix with low Nd/Yb, mantle-derived mafic magmas with lower Mg#. In the Glacier Creek HMA, elevated whole-rock MgO and SiO2 contents resulted from accumulation of xenocrystic olivine and differentiation processes, respectively, but the cause of high Nd/Yb is less clear. However, high whole-rock Sr/P (fluid mobile/fluid immobile) values indicate a mantle source that was fluxed by an enriched, hydrous slab component, likely producing the observed high Nd/Yb REE signature. The Lightning Creek HMBA is a hybridized rock unit with at least three identifiable magmatic components, but only one of which has HMA characteristics. Cr and Mg contents in Cr-spinel and olivine pairs in this HMA component suggest that its source is a strongly depleted mantle, and high

  8. Volcanic Deformation Interpretations From Campaign-Mode GPS Measurements of the Commonwealth of Dominica, Lesser Antilles, 2001-2003 Epoch I Data

    Science.gov (United States)

    Parra, J. G.; Turner, H. L.; Blessing, B. C.; Davidson, R. T.; Fitzgibbon, K.; Jansma, P.; Mattioli, G.

    2004-12-01

    The Commonwealth of Dominica is located on the eastern margin of the Caribbean plate midway along the Lesser Antilles Arc. It is the most mountainous of the Lesser Antilles, primarily due to its seven potentially active volcanic centers. A shallow seismic swarm was recorded in southern Dominica from September 20, 1998 to June 30, 2001. This seismicity prompted geodetic investigation due to its relative shallow nature and arc-shaped distribution around the peaks of Morne Anglais, Morne Plat Paye, and Morne Patates. A second seismic swarm took place in 2003. This seismicity clustered in the north of the Island in the vicinity of Morne Aux Diable. Campaign GPS observations were done using Ashtech Z-12 dual frequency, code-phase GPS receivers, with choke ring antennae. Three types of mounting systems were used depending on differing site restrictions. A total of 18 established monuments now exist throughout Dominica: nine were constructed in 2001 after the first seismic swarm occurred and three in 2003 after a second seismic swarm. Six additional sites were installed in June 2004. This presentation will focus on data collected from the 2001 and 2003 campaigns. Absolute point positions were obtained and velocity vectors were resolved in June 2003 for the initial nine benchmarks. Each data point was then compared with previously measured locations in 2001. Seven of the nine sites are located in the south where much of the seismic activity had been concentrated. The remaining two sites are located in the north. The preliminary velocity field is complex. All of the sites showed some measure of local deformation over a 2-year period. In the southern portion of the island, a set of vectors located in the Gommier Estate (GOMM) and Wotten Waven School (WOTT) point toward each other as well as towards the largest concentration of 2001 seismic epicenters. The vector for GOMM exhibited a velocity of 4.21 mm/a trending N68.1°E. WOTT displayed a velocity of 5.38 mm/a trending S16

  9. H 2O in basalt and basaltic andesite glass inclusions from four subduction-related volcanoes

    Science.gov (United States)

    Sisson, T. W.; Layne, G. D.

    1993-06-01

    Total dissolved H 2O and major element abundances were measured in basalt and basaltic andesite glass inclusions in olivine phenocrysts from Quaternary eruptions of four subduction-related volcanoes to test the hypothesis that low-MgO high-alumina basalts contain high H 2O at depth [1] and to reveal any petrogenetically significant correlations between arc basalt compositions and H 2O contents. Total dissolved H 2O (combined molecular H 2O and OH groups) measured by ion microprobe in mafic glass inclusions from the 1974 eruption of Fuego, Guatemala, reaches 6.2 wt.%. Dissolved H 2O contents decrease in more evolved Fuego glasses. Correlations of H 2O with MgO, Na 2O, K 2O, S and Cl indicate that aqueous fluid exsolution during magma ascent forced crystallization and differentiation of residual liquids. Low-K 2O magnesian high-alumina basalt glass inclusions from the 3 ka eruption of Black Crater (Medicine Lake volcano, California) have low H 2O contents, near 0.2 wt.%, which are consistent with the MORB-like character of these and other primitive lavas of the Medicine Lake region. Basalt and basaltic andesite glass inclusions from Copco Cone and Goosenest volcano on the Cascade volcanic front north of Mt. Shasta have H 2O contents of up to 3.3 wt.%. The range of H 2O contents in Cascade mafic magmas is too large to have resulted solely from enrichment by crystallization and indicates the participation of an H 2O-rich component in magma generation or crustal-level modification. Whereas fluid-absent melting of amphibole-bearing peridotite can account for the H 2O in most mafic arc liquids, the very high H 2O/alkali ratios of the 1974 Fuego eruptives suggest that an aqueous fluid was involved in the generation of Fuego basalts.

  10. Halogen behaviours during andesitic magma degassing: from magma chamber to volcanic plume

    Science.gov (United States)

    Balcone-Boissard, H.; Villemant, B.; Boudon, G.; Michel, A.

    2009-04-01

    Halogen (F, Cl, Br and I) behaviours during degassing of H2O-rich silicic magmas are investigated using volatile content analysis in glass (matrix glass and melt inclusions) of volcanic clasts (pumice and lava-dome fragments) in a series of plinian, vulcanian and lava dome-forming eruptions. Examples are taken from andesitic systems in subduction zones: Montagne Pelée and Soufrière Hills of Montserrat (Lesser Antilles) and Santa Maria-Santiaguito (Guatemala). Halogens behaviour during shallow degassing primarily depends on their incompatible character in melts and on H2O solubility. But variations in pre-eruptive conditions, degassing kinetics and syn-eruptive melt crystallisation, induce large variations in halogen extraction efficiency during H2O degassing, up to prevent halogen loss. In all studied systems, Cl, Br and I are not fractionated neither by differentiation nor by degassing processes: thus Cl/Br/I ratios remain well preserved in melts from reservoirs to eruption. These ratios measured in erupted clasts are characteristic of pre-eruptive magma compositions and may be used to trace deep magmatic processes. Moreover, during plinian eruptions, Cl, Br and I are extracted by H2O degassing but less efficiently than predicted by available experimental fluid-melt partition coefficients, by a factor as high as 5. F behaves as an incompatible element and, contrary to other halogens, is never significantly extracted by degassing. Degassing during lava dome-forming eruptions of andesitic magmas occurs mainly at equilibrium and is more efficient at extracting halogens and H2O than explosive degassing. The mobility of H2O and halogens depends on their speciation in both silicate melts and exsolved fluids which strongly varies with pressure. We suggest that the rapid pressure decrease during highly explosive eruptions prevents complete volatile speciation at equilibrium and consequently strongly limits halogen degassing.

  11. Quantitative geometric description of fracture systems in an andesite lava flow using terrestrial laser scanner data

    Science.gov (United States)

    Massiot, Cécile; Nicol, Andrew; Townend, John; McNamara, David D.; Garcia-Sellés, David; Conway, Chris E.; Archibald, Garth

    2017-07-01

    Permeability hosted in andesitic lava flows is dominantly controlled by fracture systems, with geometries that are often poorly constrained. This paper explores the fracture system geometry of an andesitic lava flow formed during its emplacement and cooling over gentle paleo-topography, on the active Ruapehu volcano, New Zealand. The fracture system comprises column-forming and platy fractures within the blocky interior of the lava flow, bounded by autobreccias partially observed at the base and top of the outcrop. We use a terrestrial laser scanner (TLS) dataset to extract column-forming fractures directly from the point-cloud shape over an outcrop area of ∼3090 m2. Fracture processing is validated using manual scanlines and high-resolution panoramic photographs. Column-forming fractures are either steeply or gently dipping with no preferred strike orientation. Geometric analysis of fractures derived from the TLS, in combination with virtual scanlines and trace maps, reveals that: (1) steeply dipping column-forming fracture lengths follow a scale-dependent exponential or log-normal distribution rather than a scale-independent power-law; (2) fracture intensities (combining density and size) vary throughout the blocky zone but have similar mean values up and along the lava flow; and (3) the areal fracture intensity is higher in the autobreccia than in the blocky zone. The inter-connected fracture network has a connected porosity of ∼0.5 % that promote fluid flow vertically and laterally within the blocky zone, and is partially connected to the autobreccias. Autobreccias may act either as lateral permeability connections or barriers in reservoirs, depending on burial and alteration history. A discrete fracture network model generated from these geometrical parameters yields a highly connected fracture network, consistent with outcrop observations.

  12. Tectonic Implications of Recent Campaign GPS Measurements Along the Central Region of the Lesser Antilles arc: Results from Dominica 2001-2004

    Science.gov (United States)

    Blessing, B. C.; Turner, H. L.; Fitzgibbon, K.; Davidson, R.; Parra, J.; Jansma, P. E.; Mattioli, G. S.

    2004-12-01

    The volcanic island of Dominica is located in the central region of the Lesser Antilles arc, an obliquely convergent boundary between the Caribbean and North American plates. An initial GPS campaign was conducted in 2001 to expand our regional GPS field for the eastern Caribbean and to provide baseline geodetic data for examining volcanic unrest in Dominica. In 2001, nine sites were established, the majority near the southern volcanic region, where a recent shallow seismic swarm had occurred. A second GPS campaign was conducted in 2003, following another seismic swarm in the north. This campaign re-occupied the original nine sites and established three more. The density of GPS sites on the island was improved and all the existing sites were reoccupied in 2004. Today there are eighteen high precision GPS sites on the island. All GPS observations were made with dual-frequency, code-phase receivers and choke ring antenna. At least 2.5 days of continuous observations were obtained on each site for each epoch in 2001, 2003, and 2004. Daily site positions were calculated with an absolute point positioning strategy using GIPSY-OASIS-II and final precise orbit and clock corrections from JPL. The measured surface deformation field on Dominica potentially contains components of motion from both shallow volcanic sources as well as elastic strain accumulation from the plate interface. Because volcanic deformation may be cyclical and superimposed on the background tectonic deformation field, we have chosen to examine on the observations from the far eastern and southern sites on the island, located well away from the region of shallow seismicity and any potentially active volcanic system. Caribbean-fixed residual velocity magnitudes range from 2±2 to 8±2 mm/yr directed approximately west. Although these results must be regarded as preliminary, they are consistent with simple models of elastic strain accumulation along the plate interface.

  13. ACTIVIDAD INSECTICIDA DE ACEITES ESENCIALES DE DOS ESPECIES DE Eucalyptus SOBRE Rhyzopertha dominica Y SU EFECTO EN ENZIMAS DIGESTIVAS DE PROGENIES

    Directory of Open Access Journals (Sweden)

    Ramiro Reyes-Guzmán

    2012-01-01

    proteolítica de las progenies; sin embargo, solamente E. globulus ocasionó la muerte de éstas (P < 0.05. Al incrementar el volumen de aceite de E. camadulensis, la actividad proteolítica del insecto aumentó, incluso al mayor tiempo de exposición. Los resultados de este estudio muestran que la fracción volátil de los aceites esenciales de eucalipto, especialmente la de E. globulus, es un agente insecticida efectivo para el control de R. dominica en trigo almacenado.

  14. Magmatic relationships and ages between adakites, magnesian andesites and Nb-enriched basalt-andesites from Hispaniola: Record of a major change in the Caribbean island arc magma sources

    Science.gov (United States)

    Escuder Viruete, J.; Contreras, F.; Stein, G.; Urien, P.; Joubert, M.; Pérez-Estaún, A.; Friedman, R.; Ullrich, T.

    2007-12-01

    Located in the Cordillera Central of the Dominican Republic, the Late Cretaceous Tireo Fm (TF) records a major change of the magma sources in the Caribbean island arc. It comprises a > 3 km thick sequence of arc-related volcanic and volcano-sedimentary rocks with variable geochemical characteristics. Combined detailed mapping, stratigraphy, geochemistry and U-Pb/Ar-Ar geochronology show that the volcanic rocks of the Tireo Fm include two main volcanic sequences. The lower volcanic sequence is dominated by monotonous submarine vitric-lithic tuffs and volcanic breccias of andesite to basaltic andesite, with minor interbedded flows of basalts and andesites. Fossil and (U-Pb and 40Ar- 39Ar) geochronological data show that arc magmatism in the lower sequence began to accumulate before ˜ 90 Ma, from the Aptian to Turonian. These rocks constitute an island arc tholeiitic suite, derived from melting by fluxing of a mantle wedge with subduction-related hydrous fluids. The upper volcanic sequence is characterized by a spatial and temporal association of adakites, high-Mg andesites, and Nb-enriched basalts, which collectivelly define a shift in the composition of the subduction-related erupted lavas. A dacitic to rhyolitic explosive volcanism with subaerial and episodic aerial eruptions, and sub-volcanic emplacements of domes, characterize mainly this stratigraphic interval. The onset of this volcanism took place at Turonian-Coniacian boundary and continued in the Santonian to Lower Campanian, with minor events in the Late Campanian. Adakites represent melts of the subducting slab, magnesian andesites the product of hybridization of adakite liquids with mantle peridotite, and Nb-enriched basalts melts of the residue from hybridization. We propose a model of oblique ridge subduction at ˜ 90 Ma and possibly subsequent slab window formation, as principal cause of magmatic variations recorded in the Caribbean island arc, above a southwestern-dipping subduction zone.

  15. Generation of new continental crust by sublithospheric silicic-magma relamination in arcs: A test of Taylor's andesite model

    NARCIS (Netherlands)

    Castro, Antonio; Vogt, Katharina; Gerya, Taras

    2013-01-01

    The paradox of the Earth's continental crust is that although this reservoir is generally regarded as having differentiated from the mantle, it has an andesitic bulk composition that contrasts with the intrinsic basaltic composition of mantle-derived melts. Classical models for new crust generation

  16. A GPS inspired Terrain Referenced Navigation algorithm

    NARCIS (Netherlands)

    Vaman, D.

    2014-01-01

    Terrain Referenced Navigation (TRN) refers to a form of localization in which measurements of distances to the terrain surface are matched with a digital elevation map allowing a vehicle to estimate its own position within the map. The main goal of this dissertation is to improve TRN performance thr

  17. A GPS inspired Terrain Referenced Navigation algorithm

    NARCIS (Netherlands)

    Vaman, D.

    2014-01-01

    Terrain Referenced Navigation (TRN) refers to a form of localization in which measurements of distances to the terrain surface are matched with a digital elevation map allowing a vehicle to estimate its own position within the map. The main goal of this dissertation is to improve TRN performance thr

  18. Photometric Characteristics of Lunar Terrains

    Science.gov (United States)

    Sato, Hiroyuki; Hapke, Bruce W.; Denevi, Brett W.; Robinson, Mark

    2016-10-01

    The photometric properties of the lunar depend on albedo, surface roughness, porosity, and the internal/external structure of particles. Hapke parameter maps derived using a bidirectional reflectance model [Hapke, 2012] from Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) images demonstrated the spatial and spectral variation of the photometric properties of the Moon [Sato et al., 2014]. Using the same methodology, here we present the photometric characteristics of typical lunar terrains, which were not systematically analyzed in the previous study.We selected five representative terrain types: mare, highland, swirls, and two Copernican (fresh) crater ejecta (one mare and one highlands example). As for the datasets, we used ~39 months of WAC repeated observations, and for each image pixel, we computed latitude, longitude, incidence, emission, and phase angles using the WAC GLD100 stereo DTM [Scholten et al., 2012]. To obtain similar phase and incidence angle ranges, all sampling sites are near the equator and in the vicinity of Reiner Gamma. Three free Hapke parameters (single scattering albedo: w, HG2 phase function parameter: c, and angular width of SHOE: hs) were then calculated for the seven bands (321-689 nm). The remaining parameters were fixed by simplifying the model [Sato et al., 2014].The highlands, highland ejecta, and swirl (Reiner Gamma) showed clearly higher w than the mare and mare ejecta. The derived c values were lower (less backscattering) for the swirl and higher (more backscattering) for the highlands (and ejecta) relative to the other sites. Forward scattering materials such as unconsolidated transparent crystalline materials might be relatively enriched in the swirl. In the highlands, anorthositic agglutinates with dense internal scattering could be responsible for the strong backscattering. The mare and mare ejecta showed continuously decreasing c from UV to visible wavelengths. This might be caused by the FeO-rich pyroxene

  19. Walking Algorithm of Humanoid Robot on Uneven Terrain with Terrain Estimation

    Directory of Open Access Journals (Sweden)

    Jiang Yi

    2016-02-01

    Full Text Available Humanoid robots are expected to achieve stable walking on uneven terrains. In this paper, a control algorithm for humanoid robots walking on previously unknown terrains with terrain estimation is proposed, which requires only minimum modification to the original walking gait. The swing foot trajectory is redesigned to ensure that the foot lands at the desired horizontal positions under various terrain height. A compliant terrain adaptation method is applied to the landing foot to achieve a firm contact with the ground. Then a terrain estimation method that takes into account the deformations of the linkages is applied, providing the target for the following correction and adjustment. The algorithm was validated through walking experiments on uneven terrains with the full-size humanoid robot Kong.

  20. Human Robotic Systems (HRS): Extreme Terrain Mobility Element

    Data.gov (United States)

    National Aeronautics and Space Administration — During 2014, the Extreme Terrain Mobility project element is developing five technologies:Exoskeleton Development for ISS EvaluationExtreme Terrain Mobility...

  1. Paleoproterozoic crustal evolution in the East Sarmatian Orogen: Petrology, geochemistry, Sr-Nd isotopes and zircon U-Pb geochronology of andesites from the Voronezh massif, Western Russia

    Science.gov (United States)

    Terentiev, R. A.; Savko, K. A.; Santosh, M.

    2016-03-01

    Andesites and related plutonic rocks are major contributors to continental growth and provide insights into the interaction between the mantle and crust. Paleoproterozoic volcanic rocks are important components of the East Sarmatian Orogen (ESO) belonging to the East European Craton, although their petrogenesis and tectonic setting remain controversial. Here we present petrology, mineral chemistry, bulk chemistry, Sr-Nd isotopes, and zircon U-Pb geochronological data from andesites and related rocks in the Losevo and Vorontsovka blocks of the ESO. Clinopyroxene phenocrysts in the andesites are depleted in LREE, and enriched in HFSE (Th, Nb, Zr, Hf, Ti) and LILE (Ba, Sr). Based on the chemistry of pyroxenes and whole rocks, as well as Fe-Ti oxides, we estimate a temperature range of 1179 to 1262 °C, pressures of 11.3 to 13.0 kbar, H2O content of 1-5 wt.%, and oxygen fu gacity close to the MH buffer for the melts of the Kalach graben (KG) and the Baygora area (BA) andesites. Our zircon U-Pb geochronological data indicate new zircon growth during the middle Paleoproterozoic as displayed by weighted mean 207Pb/206Pb ages of 2047 ± 17 Ma and 2040 ± 16 Ma for andesite and dacite-porphyry of the BA, and 2050 ± 16 Ma from high-Mg basaltic andesite of the KG. The andesites and related rocks of the KG and BA are characterized by high magnesium contents (Mg # up to 0.68). All these volcanic rocks are depleted in LREE and HFSE, and display negative Nb and Ti anomalies relative to primitive mantle. The high-Mg bulk composition, and the presence of clinopyroxene phenocrysts suggests that the parent melts of the KG and BA suite were in equilibrium with the mantle rocks. The rocks show positive εNd(T) values and low initial 87Sr/86Sr, suggesting that the magmas were mostly derived from metasomatized mantle source. The geochemical differences between the two andesite types are attributed to: the predominance of fractional crystallization, and minor role of contamination in the

  2. Genetic linkage analysis of the lesser grain borer Rhyzopertha dominica identifies two loci that confer high-level resistance to the fumigant phosphine.

    Science.gov (United States)

    Schlipalius, David I; Cheng, Qiang; Reilly, Paul E B; Collins, Patrick J; Ebert, Paul R

    2002-01-01

    High levels of inheritable resistance to phosphine in Rhyzopertha dominica have recently been detected in Australia and in an effort to isolate the genes responsible for resistance we have used random amplified DNA fingerprinting (RAF) to produce a genetic linkage map of R. dominica. The map consists of 94 dominant DNA markers with an average distance between markers of 4.6 cM and defines nine linkage groups with a total recombination distance of 390.1 cM. We have identified two loci that are responsible for high-level resistance. One provides approximately 50x resistance to phosphine while the other provides 12.5x resistance and in combination, the two genes act synergistically to provide a resistance level 250x greater than that of fully susceptible beetles. The haploid genome size has been determined to be 4.76 x 10(8) bp, resulting in an average physical distance of 1.2 Mbp per map unit. No recombination has been observed between either of the two resistance loci and their adjacent DNA markers in a population of 44 fully resistant F5 individuals, which indicates that the genes are likely to reside within 0.91 cM (1.1 Mbp) of the DNA markers. PMID:12072472

  3. Bioactivity of Lemon Oil against Rhizopertha dominica Fabricius%柠檬精油对谷蠹的生物活性

    Institute of Scientific and Technical Information of China (English)

    李宁; 胡奇; 崔新仪

    2013-01-01

    [目的]植物精油可以克服仓储害虫化学防治的种种弊端.[方法]以谷蠹为试虫,研究了不同剂量柠檬精油对谷蠹的室内生物活性.[结果]柠檬精油100 μL/L处理对谷蠹成虫不仅具有较强的熏蒸活性和驱避活性,而且对其幼虫的羽化有一定的抑制作用.[结论]室内生物活性测定结果表明柠檬精油有望开发成一种绿色无污染的仓储害虫杀虫剂.%[Aims] Plant essential oil can control the disadvantages of chemical control of storage pests. [Methods] Bioactivity of different dose lemon essential oil against Rhizopertha dominnica was detected by the indoor bioassay. [Results] The treatment of 100 μL/L lemon essential oil not only had stomg fumigation and repellency against the adults of R. dominica, but also had certain influence on growth and development against the larva of R. dominica. [Conclusions] Indoor bioassay showed that lemon essential oil is expected to be developed into a green pollution-free insecticide against storage pests.

  4. Insecticidal efficacy of three vegetable oils as post-harvest grain protectants of stored wheat against Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae)

    Institute of Scientific and Technical Information of China (English)

    AMIN NIKPAY

    2007-01-01

    The lesser grain borer, Rhyzopertha dominica is a major insect pests of stored grain in the tropics. Vegetable oils (chamomile, sweet almond and coconut) at 2.5, 3.5, 5.0,7.0 and 10.0 mL/kg were tested against Rhyzopertha dominica (F.) in wheat grain. All bioassays were conducted at 30℃ and 65% ± 2% RH. Treatments with vegetable oils at high dose (10.0 mL/kg) achieved over 95% control within 24 h of exposure to freshly treated grain.There was little difference between the three oils in their effect. Persistence of oils in grains was tested at short-term storage intervals (48, 72 and 96 h) and intermediate-term intervals (10, 20 and 30 days) after treatments. The activity of all products decreased with storage period. Seed viability was reduced by the high dose rate (10.0 mL/kg) ofoil treatments. The potential use of vegetable oils as supplementary or alternative grain protectants against insect damage in traditional grain storage in developing countries is discussed.

  5. Pelargonium graveolens L'Her. and Artemisia arborescens L. essential oils: chemical composition, antifungal activity against Rhizoctonia solani and insecticidal activity against Rhysopertha dominica.

    Science.gov (United States)

    Bouzenna, Hafsia; Krichen, Lamia

    2013-01-01

    The chemical composition of the Pelargonium graveolens essential oil allowed the identification of 15 compounds (93.86% of the total essential oil). The major fractions were citronellol (35%) and geraniol (28.8%). The chemical composition of the Artemisia arborescens essential oil revealed twenty-one compounds representing 93.57% of the total essential oil. The main compounds were chamazulene (31.9%) and camphor (25.8%). The insecticidal effects were tested towards the insect Rhysopertha dominica. Results revealed that these two essential oils were highly effective against R. dominica at the dose of 50 µL on Petri dish of 8.5 cm of diameter. The antifungal activity was evaluated against Rhizoctonia solani and results showed that both of the essential oils were highly active at a dose of 12.5 µL/20 mL of PDA. Moreover, the inhibitory effect of P. graveolens essential oil was evidenced as stronger than that of the A. arborescens oil for all the tested doses.

  6. Subaqueous cryptodome eruption, hydrothermal activity and related seafloor morphologies on the andesitic North Su volcano

    Science.gov (United States)

    Thal, Janis; Tivey, Maurice; Yoerger, Dana R.; Bach, Wolfgang

    2016-09-01

    North Su is a double-peaked active andesite submarine volcano located in the eastern Manus Basin of the Bismarck Sea that reaches a depth of 1154 m. It hosts a vigorous and varied hydrothermal system with black and white smoker vents along with several areas of diffuse venting and deposits of native sulfur. Geologic mapping based on ROV observations from 2006 and 2011 combined with morphologic features identified from repeated bathymetric surveys in 2002 and 2011 documents the emplacement of a volcanic cryptodome between 2006 and 2011. We use our observations and rock analyses to interpret an eruption scenario where highly viscous, crystal-rich andesitic magma erupted slowly into the water-saturated, gravel-dominated slope of North Su. An intense fragmentation process produced abundant blocky clasts of a heterogeneous magma (olivine crystals within a rhyolitic groundmass) that only rarely breached through the clastic cover onto the seafloor. Phreatic and phreatomagmatic explosions beneath the seafloor cause mixing of juvenile and pre-existing lithic clasts and produce a volcaniclastic deposit. This volcaniclastic deposit consists of blocky, non-altered clasts next, variably (1-100%) altered clasts, hydrothermal precipitates and crystal fragments. The usually applied parameters to identify juvenile subaqueous lava fragments, i.e. fluidal shape or chilled margin, were not applicable to distinguish between pre-existing non-altered clasts and juvenile clasts. This deposit is updomed during further injection of magma and mechanical disruption. Gas-propelled turbulent clast-recycling causes clasts to develop variably rounded shapes. An abundance of blocky clasts and the lack of clasts typical for the contact of liquid lava with water is interpreted to be the result of a cooled, high-viscosity, crystal-rich magma that failed as a brittle solid upon stress. The high viscosity allows the lava to form blocky and short lobes. The pervasive volcaniclastic cover on North Su is

  7. Origins of Calc-Alkaline (s.l.) Andesitic Magmas - Where We Stand Today

    Science.gov (United States)

    Sisson, T. W.

    2015-12-01

    The mainly igneous continents have intermediate mean SiO2 (~60 wt%) and Mg# (0.4-0.55 mol). Bowen championed crystallization-differentiation of basalts to silicic daughter liquids, but he encountered difficulties with conflicting evidence for iron enrichment. We now know that as dry reduced basalts crystallize, melt SiO2 begins climbing steeply at F (melt fraction): 0.25-0.35, reaching intermediate values at F: 0.1-0.2. H2O changes basalt crystallization by (1) increasing the ratio of olivine to high-Ca pyroxene, (2) delaying onset and reducing the proportion of plagioclase, (3) stabilizing calcic plagioclase, (4) destabilizing low-Ca pyroxene, (5) eventually stabilizing amphibole, and (6) destabilizing silicate minerals more than magnetite. Factors 1-5 enrich melts early in SiO2, 6 limits decline of Mg#. H2O of 2-6 wt% is sufficient for early SiO2 enrichment; fO2 modestly above Ni-NiO yields daughter liquids with high (calc-alkaline) Mg#s. These values are matched by many natural subduction zone magmas, so seemingly, the problem is solved. Yet, difficulties remain: Melt SiO2 enrichment commences at F: 0.6-0.7 in experiments on hydrous Mg basalts, reaching intermediate SiO2 at F: 0.2-0.4. Cumulates 60-80% of the basalt mass must have returned to the mantle if basalt differentiation formed the continents. Differentiation mainly near the base of the crust has geologic support, and would aid disposal of cumulates, but most experiments on hydrous basalts at such pressures yield peraluminous andesitic liquids, unlike common metaluminous andesites. A composite scenario avoiding peraluminous intermediates is crystallization-differentiation plus mixing with silicic liquids mainly residual or remelted from shortly antecedent intrusions. Even in this case, cumulates and restites exceeding the continental mass must have been lost. The Archean was different: Residual-eclogite-sourced granitoids are widespread, but experiments on hydrous eclogites at plausible temperatures

  8. Controls on long-term low explosivity at andesitic arc volcanoes: Insights from Mount Hood, Oregon

    Science.gov (United States)

    Koleszar, Alison M.; Kent, Adam J. R.; Wallace, Paul J.; Scott, William E.

    2012-03-01

    The factors that control the explosivity of silicic volcanoes are critical for hazard assessment, but are often poorly constrained for specific volcanic systems. Mount Hood, Oregon, is a somewhat atypical arc volcano in that it is characterized by a lack of large explosive eruptions over the entire lifetime of the current edifice (~ 500,000 years). Erupted Mount Hood lavas are also compositionally homogeneous, with ~ 95% having SiO2 contents between 58 and 66 wt.%. The last three eruptive periods in particular have produced compositionally homogeneous andesite-dacite lava domes and flows. In this paper we report major element and volatile (H2O, CO2, Cl, S, F) contents of melt inclusions and selected phenocrysts from these three most recent eruptive phases, and use these and other data to consider possible origins for the low explosivity of Mount Hood. Measured volatile concentrations of melt inclusions in plagioclase, pyroxene, and amphibole from pumice indicate that the volatile contents of Mount Hood magmas are comparable to those in more explosive silicic arc volcanoes, including Mount St. Helens, Mount Mazama, and others, suggesting that the lack of explosive activity is unlikely to result solely from low intrinsic volatile concentrations or from substantial degassing prior to magma ascent and eruption. We instead argue that an important control over explosivity is the increased temperature and decreased magma viscosity that results from mafic recharge and magma mixing prior to eruption, similar to a model recently proposed by Ruprecht and Bachmann (2010). Erupted Mount Hood magmas show extensive evidence for mixing between magmas of broadly basaltic and dacitic-rhyolitic compositions, and mineral zoning studies show that mixing occurred immediately prior to eruption. Amphibole chemistry and thermobarometry also reveal the presence of multiple amphibole populations and indicate that the mixed andesites and dacites are at least 100 °C hotter than the high-SiO2

  9. The Origin of Voluminous Dacite (vs. Andesite) at Mature, Thick Continental Arcs: A Reflection of Processes in the Deep Crust

    Science.gov (United States)

    Lange, R. A.

    2013-12-01

    An outstanding question is why some continental arc segments are characterized by voluminous eruptions of dacite (65-70 wt% SiO2), whereas others erupt more andesite (58-64 wt% SiO2) than any other magma type. An example of the former is the Altiplano-Puna region of the central Andean arc, which has erupted a predominance of dacite over all magma types 10-1 Ma (de Silva, 1989). In contrast, a 200-km arc segment of the Mexican volcanic arc (Michoacán-Guanajuato arc segment) has erupted ~75% andesite, ~26% basaltic andesite and 20%) of hornblende-rich (~40%) gabbronorite in the deep crust, driven by mantle-derived basalt intrusions at depths of 30-40 km. The absence of any dacite or rhyolite along this arc segment indicates that interstitial liquid from crystal-rich andesites never segregated to form eruptible magma. Thus, little upper-crust differentiation occurred along this arc segment. On the basis of phase-equilibrium experiments in the literature (e.g., Sisson et al., 2005), it is proposed that rhyolite and dacite did form during partial melting of the lower arc crust, but at melt fractions too low (≤15%) to permit efficient transport to the upper crust (Vigneresse and Tikoff, 1999). It is further proposed that the reason why dacite is so abundant at mature thick continental arcs (e.g., Altiplano-Puno complex) may be because mantle-derived basalts are primarily emplaced at similar depths (~30-40 km) in continental arc crustal columns. If so, in the central Andean arc, a depth of 30-40 km is within the middle dioritic crust (Graeber and Asch, 1999). Partial melts of hornblende diorite (vs. hornblende gabbro) are predicted to be dacitic (vs. andesitic) at melt fractions of 20-25%, which permits transport to the upper crust. It is therefore proposed that it is deep crustal processes that determine whether andesite or dacite is the most voluminous magma type emplaced into the upper crust and erupted at arcs.

  10. Experimental Insights Into the Formation of High-Mg Andesites in the Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Weber, R. M.; Wallace, P. J.; Johnston, A.

    2010-12-01

    High-Mg basaltic andesites and andesites occur in the central Trans-Mexican Volcanic Belt, primarily in the Chichinautzin Volcanic Field south of Mexico City, and their primitive chemical characteristics suggest equilibration with mantle peridotite. These lavas may represent either slab melts that re-equilibrated with peridotite during ascent or hydrous partial melts of a peridotite source. We have experimentally mapped the liquidus mineralogy for a high-Mg basaltic andesite (9.6 wt% MgO, 54.4 wt% SiO2) from the Pelagatos cinder cone as a function of temperature and water content over a range of mantle wedge pressures. We chose this primitive composition rather than a true andesite because samples from the Chichinautzin region with >55 wt% SiO2 and relatively high MgO and Mg# contain textural evidence for contamination in the form of quartz xenocrysts or reaction products. Our experimental results show that the Pelagatos composition could be in equilibrium with a harzburgite residue (with Fo90 olivine) at relatively high water contents (>7 wt%) and low temperatures (1080-1150°C) at pressures ranging from 11 to 14 kbar. These results agree well with a published thermobarometer for peridotite melting, so we use this thermobarometer to estimate equilibration conditions for other primitive magmas in the region. In contrast to the high Ni contents found in olivine phenocrysts in many high-Mg basaltic andesites and andesites produced in Chichinautzin, the olivine phenocrysts in the Pelagatos lava contain Ni contents typical of lherzolite or harzburgite melts that have subsequently fractionated a small amount of olivine after segregating from their mantle source. Because the refractory mantle source for Pelagatos may have had Fo>90 olivine, we estimate formation conditions for the composition recalculated to be in equilibrium with Fo92 olivine. This calculation shifts equilibration conditions to higher temperatures (1190-1270°C) at mantle wedge pressures (11-14 kbar

  11. Genesis of high-Mg andesites through shallow fractionation of primitive arc basalts at elevated oxygen fugacities

    Science.gov (United States)

    Zellmer, G. F.; Shellnutt, J. G.

    2009-12-01

    The petrogenesis of high-Mg andesites has been linked to a variety of processes, including partial melting of hydrous mantle peridotite, re-equilibration of partial melts of the subducting slab with the mantle wedge, and assimilation of lower crustal cumulates into dacitic melts. Yet none of these processes can explain the recently identified association of adakitic andesites, many of which are high-Mg andesites, with regions of elevated surface heat flux that are likely related to unusually shallow magma ponding levels in the upper crust (Zellmer, 2009). Using MELTS modeling, we demonstrate here that at high oxygen fugacities (NNO+2, which based on whole-rock Fe3+/Fe2+ ratios is appropriate for the Western and Central Aleutians, the Trans-Mexican Volcanic Belt, and the Setouchi Volcanic Belt), shallow crustal pressures (0.7 kbar), and initial H2O contents between 0.5 and 4 wt%, iron-magnesium spinel will be fractionated from primitive arc basalts, producing andesitic residual melts with elevated Mg#. Subsequent assimilation of a few percent of autocrystic mafic phases makes typical high-Mg andesites with forsteritic olivines. Orthopyroxenes in equilibrium with these melts are Cr-rich due to increased uptake of Cr into orthopyroxene (Dopx/lq≥25) at lower temperatures (≤1130°C) and elevated oxygen fugacities (NNO+2). While arc magmas with high initial H2O contents will undergo early degassing induced crystallization and viscous stagnation, lower primary melt H2O contents will result in delayed crystallization and shallower magma ponding levels, accounting for elevated surface heat flux. Our findings are therefore consistent with the location of many high-Mg andesites in areas of high surface heat flux, and challenge the commonly accepted notion that these compositions are particularly hydrous primary melts generated in equilibrium with mantle peridotite. Reference: Zellmer G.F. (2009) Petrogenesis of Sr-rich adakitic rocks at volcanic arcs: insights from global

  12. Geochemistry and petrology of andesites from the north rift zone of Axial Seamount, Juan de Fuca Ridge

    Science.gov (United States)

    Smithka, I. N.; Perfit, M. R.; Clague, D. A.; Wanless, V. D.

    2014-12-01

    In 2013, the ROV Doc Ricketts onboard R/V Western Flyer explored ~4 km of an elongate pillow ridge up to ~300 m high along the eastern edge of the north rift zone of Axial Seamount. The steep-sided volcanic ridge is constructed of large pillow lavas up to 2-3 m in diameter and smaller elongated pillow tubes. Of the 27 samples collected during dive D526, all but one are andesites making it one of the largest confirmed high-silica exposures along a mid-ocean ridge (MOR). Based on radiocarbon ages of sediment on top of flows, the mounds are at least ~1390 years old. This minimum age is much younger than the 56 Ka age calculated based on distance from the rift axis, indicating eruption off-axis through older, colder crust and supporting the hypothesis and model calculations that extensive fractional crystallization (>85%) caused the high silica content. The andesitic lavas are primarily glassy, highly vesicular, crusty, and sparsely phyric with small (~1 mm) plagioclase crystals and olivine, clinopyroxene, and Fe-Ti oxide microphenocrysts. Microprobe analyses of glasses are similar to wax-core samples previously collected from this area but are more compositionally variable. Excluding one basalt (7.7 wt% MgO) sampled between mounds, the lavas are basaltic andesites and andesites (53-59 wt% SiO2) with <3 wt% MgO and 12.8-15.7 wt% FeO concentrations. Incompatible trace element abundances are ~4-6 times more enriched than in Axial Seamount T-MORB. Primitive mantle-normalized patterns are similar to those of high-silica lavas from other MORs (southern Juan de Fuca Ridge, 9N East Pacific Rise) with significant positive U anomalies, large negative Sr anomalies, small negative Eu anomalies, and slight positive Zr-Hf anomalies. The andesites are more enriched in light rare earth elements than basalts from Axial Seamount ((La/Yb)N 1.35-1.4 vs. 0.7-1.27) and N-MORB from the southern Juan de Fuca Ridge. The andesites also have high Cl (~0.3-0.6 wt%) and H2O (~1.60-1.71 wt

  13. Petrogenesis of Mount Rainier andesite: magma flux and geologic controls on the contrasting differentiation styles at stratovolcanoes of the southern Washington Cascades

    Science.gov (United States)

    Sisson, Thomas W.; Salters, V.J.M.; Larson, P.B.

    2013-01-01

    Quaternary Mount Rainier (Washington, USA) of the Cascades magmatic arc consists of porphyritic calc-alkaline andesites and subordinate dacites, with common evidence for mingling and mixing with less evolved magmas encompassing andesites, basaltic andesites, and rarely, basalts. Basaltic andesites and amphibole andesites (spessartites) that erupted from vents at the north foot of the volcano represent some of Mount Rainier's immediate parents and overlap in composition with regional basalts and basaltic andesites. Geochemical (major and trace elements) and isotopic (Sr, Nd, Pb, O) compositions of Mount Rainier andesites and dacites are consistent with modest assimilation (typically ≤20 wt%) of evolved sediment or sediment partial melt. Sandstones and shales of the Eocene Puget Group, derived from the continental interior, are exposed in regional anticlines flanking the volcano, and probably underlie it in the middle to lower crust, accounting for their assimilation. Mesozoic and Cenozoic igneous basement rocks are unsuitable as assimilants due to their high 143Nd/144Nd, diverse206Pb/204Pb, and generally high δ18O.

  14. Wind turbine wake measurement in complex terrain

    Science.gov (United States)

    Hansen, KS; Larsen, GC; Menke, R.; Vasiljevic, N.; Angelou, N.; Feng, J.; Zhu, WJ; Vignaroli, A.; W, W. Liu; Xu, C.; Shen, WZ

    2016-09-01

    SCADA data from a wind farm and high frequency time series measurements obtained with remote scanning systems have been analysed with focus on identification of wind turbine wake properties in complex terrain. The analysis indicates that within the flow regime characterized by medium to large downstream distances (more than 5 diameters) from the wake generating turbine, the wake changes according to local atmospheric conditions e.g. vertical wind speed. In very complex terrain the wake effects are often “overruled” by distortion effects due to the terrain complexity or topology.

  15. Rapid crystallization during recycling of basaltic andesite tephra: timescales determined by reheating experiments.

    Science.gov (United States)

    Deardorff, Nicholas; Cashman, Katharine

    2017-04-12

    Microcrystalline inclusions within microlite-poor matrix are surprisingly common in low intensity eruptions around the world, yet their origin is poorly understood. Inclusions are commonly interpreted as evidence of crystallization along conduit margins. Alternatively, these clasts may be recycled from low level eruptions where they recrystallize by heating within the vent. We conducted a series of experiments heating basaltic andesite lapilli from temperatures below the glass transition (~690 °C) to above inferred eruption temperatures (>1150 °C) for durations of 2 to >60 minutes. At 690 °C  800 °C, crystallization occurs in active submarine volcano NW Rota-1, Mariana arc and subaerial volcano Stromboli suggest that characteristic signatures of clast recycling are different in the two environments. Specifically, chlorine assimilation provides key evidence of recycling in submarine samples, while bands of oxides bordering microcrystalline inclusions are unique to subaerial environments. Correct identification of recycling at basaltic vents will improve (lower) estimates of mass eruption rate and help to refine interpretations of eruption dynamics.

  16. Biologic Analog Science Associated with Lava Terrains

    Science.gov (United States)

    Thomas, N. K.; Hamilton, J. C.; Veillet, A.; Muir, C.

    2016-05-01

    The goal of BASALT is to use Hawaiian volcanic terrain to constrain the upper limits of biomass that could have been supported on Mars and how those upper bounds inform future detection requirements for manned missions.

  17. TERRAIN, McCRACKEN COUNTY, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. DCS Terrain Submission for Lewis County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  19. TERRAIN, ST. CLAIR COUNTY, ALABAMA USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. DCS Terrain Submission for Adair, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. DCS Terrain Submission for Logan, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN, CITY OF DALLAS, DALLAS COUNTY, TEXAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  3. DCS TERRAIN Submission for STEARNS COUNTY, MN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. DCS Terrain Submission for Rockland County NY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describe the digital topographic data that were used to create...

  5. DCS Terrain for Jasper County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  6. DCS TERRAIN SUBMISSION FOR SHELBY COUNTY, TN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  7. DCS Terrain Submission for Brazos TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. DCS Terrain Submission for Cass County, TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. DCS Terrain Submission for Irwin, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. DCS Terrain Submission for Seminole, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. Terrain Sumbission for Howard County NE

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. DCS Terrain Submission for Ector, TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. DCS Terrain for HOUSTON COUNTY, ALABAMA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  14. DCS Terrain Submission for Cass County, MO

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. DCS TERRAIN SUBMISSION FOR PUTNAM COUNTY, FL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  16. DCS Terrain Submission for Benton County, AR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  17. DCS Terrain Submission for Solano, CA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, ESSEX COUNTY, MASSACHUSETTS - Coastal PMR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  19. DCS TERRAIN SUBMISSION FOR KNOX COUNTY, TN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  20. TERRAIN, Pointe Coupee PARISH, LA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. DCS Terrain Submission for Mason County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  2. TERRAIN, UPPER CUMBERLAND WATERSHED, KENTUCKY USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  3. DCS Terrain Submission for Mississippi County AR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. TERRAIN, CERRO GORDO COUNTY, IOWA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. DCS Terrain Submission for Sanders County, Montana

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. DCS Terrain Submission for Houston TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. DCS Terrain Submission for Jackson, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. Terrain, CEDAR RAPIDS, LINN COUNTY, IA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. DCS Terrain Submission for Lagrange County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. TERRAIN Submission for Dodge Countywide DFIRM

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. DCS Terrain Submission for Chippewa County, Wisconsin

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. DCS Terrain Submission for George, MS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. DCS Terrain Submission for Harrison, TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. DCS Terrain Submission for Fox Lake PMR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. DCS Terrain for Quitman County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  16. DCS Terrain Submission for Charlton Co GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN Submission for CHISAGO COUNTY, MN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  18. DCS Terrain for Harris County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  19. DCS Terrain Submission for Carter, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. DCS Terrain for Murray County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  1. DCS Terrain Submission for Pike County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  2. DCS Terrain Submission for Hancock County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  3. DCS Terrain Submission for Magoffin County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  4. DCS Terrain Submission for Greenup County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  5. DCS Terrain Submission for Boyd County, KY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  6. DCS Terrain Submission for Lagrange County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. DCS Terrain Submission for Delaware, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. DCS Terrain Submission for Cherokee, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  9. DCS Terrain Submission for Texas, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  10. DCS Terrain Submission for Fulton County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  11. DCS Terrain Submission for Seminole, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. Dummy metadata TERRAIN, Montgomery County, Pennsylvania

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data includes digital elevation models, LIDAR derived contours, LIDAR three-dimensional spot elevations and breaklines, field surveyed ground elevations and...

  13. DCS Terrain Submission for Wabash County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. DCS Terrain Submission for Sequoyah, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. DCS Terrain Submission for Miami County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  16. DCS Terrain Submission for Pontodoc, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. TERRAIN DATA CAPTURE STANDARDS, Bedford PA, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data includes digital elevation models, LIDAR derived contours, LIDAR three-dimensional spot elevations and breaklines, field surveyed ground elevations and...

  18. DCS Terrain Submission for Lincoln, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. DCS Terrain Submission for Noble County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. DCS Terrain Submission for Woodward, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  1. DCS Terrain Submission for Gunnison County, CO

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. DCS Terrain Submission for Mayes, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  3. DCS Terrain Submission for Caddo, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. DCS Terrain Submission for Custer, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. DCS Terrain Submission for Tipton County, IN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  6. DCS Terrain Submission for Stephens, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. DCS Terrain Submission for Bark River PMR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  8. TERRAIN, BRISTOL COUNTY, RHODE ISLAND - Coastal PMR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  9. TERRAIN, UPPER CUMBERLAND WATERSHED, PMR, TENNESSEE, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  10. DCS Terrain for Pickens County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  11. DCS Terrain Submission for Ulster County NY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describe the digital topographic data that were used to create...

  12. DCS Terrain for Cobb County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  13. DCS TERRAIN SUBMISSION FOR VOLUSIA COUNTY, FL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describe the digital topographic data that were used to create...

  14. DCS Terrain Submission for Sanders County, Montana

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. DCS Terrain for Hancock County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  16. DCS Terrain Submission for Howard, AR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. DCS Terrain Submission for Winston County, AL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  18. TERRAIN, ST. LOUIS COUNTY, Missouri USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. DCS Terrain Submission for Tyler TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. DCS Terrain Submission for Citrus County FL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that were used to create...

  1. DCS Terrain Submission for Kingfisher, OK

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  2. TERRAIN DATA, CITY OF CARSON CITY, NV

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describe the digital topographic data that were used to create...

  3. TERRAIN, CANNON COUNTY, TENNESSEE and INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  4. DCS TERRAIN Submission for STEARNS COUNTY, MN

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  5. DCS Terrain for Stewart County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  6. DCS Terrain Submission for Chippewa County, Wisconsin

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  7. DCS Terrain for Warren County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  8. DCS Terrain for Middlesex County, NJ

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that were used to create...

  9. DCS Terrain for Williamson County, TX

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  10. DCS Terrain Submission for Albany County NY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describe the digital topographic data that were used to create...

  11. DCS Terrain Submission for Rusk County, Wisconsin

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. DCS Terrain for Greene County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  13. DCS Terrain for Heard County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  14. TERRAIN-FREMONT COUNTY, WY, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  15. DCS Terrain Submission for Chemung County, NY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  16. DCS Terrain Submission for Hempstead, AR

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  17. DCS Terrain for Clay County, GA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  18. NONLINEAR PREDICTIVE CONTROL FOR TERRAIN FOLLOWING

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A nonlinear continuous predictive control method was used for design of cruise missile terrain-following controller. A performance index which combined the tracking error and rate of tracking error is presented. Then an optimal nonlinear feedback control law is generated to minimize the performance index. The tracking performance and robustness of controller are discussed. The advantage of the control law is demonstrated by successfully designing cruise missile terrain following controllers. The results show that the controller exhibits robustness and excellent tracking performance.

  19. Automatic terrain modeling using transfinite element analysis

    KAUST Repository

    Collier, Nathaniel O.

    2010-05-31

    An automatic procedure for modeling terrain is developed based on L2 projection-based interpolation of discrete terrain data onto transfinite function spaces. The function space is refined automatically by the use of image processing techniques to detect regions of high error and the flexibility of the transfinite interpolation to add degrees of freedom to these areas. Examples are shown of a section of the Palo Duro Canyon in northern Texas.

  20. The MAP program: building the digital terrain model.

    Science.gov (United States)

    R.H. Twito; R.W. Mifflin; R.J. McGaughey

    1987-01-01

    PLANS, a software package for integrated timber-harvest planning, uses digital terrain models to provide the topographic data needed to fit harvest and transportation designs to specific terrain. MAP, an integral program in the PLANS package, is used to construct the digital terrain models required by PLANS. MAP establishes digital terrain models using digitizer-traced...

  1. The Cerro Bitiche Andesitic Field: petrological diversity and implications for magmatic evolution of mafic volcanic centers from the northern Puna

    Science.gov (United States)

    Maro, Guadalupe; Caffe, Pablo J.

    2016-07-01

    The Cerro Bitiche Andesitic Field (CBAF) is one of the two largest mafic volcanic fields in northern Puna (22-24° S) and is spatially and temporally associated with ignimbrites erupted from some central Andean Altiplano-Puna Volcanic Complex calderas. The CBAF comprises seven scoria cones and widespread high-K calcalkaline lava flows that cover an area of 200 km2. Although all erupted rocks have a relatively narrow chemical range (56-62 % SiO2, 3-6 % MgO), there is a broad diversity of mineral compositions and textures. The least evolved lavas (˜58-61 % SiO2) are high-Mg andesites with scarce (andesites (˜62 wt% SiO2), on the other hand, are porphyritic rocks with plagioclase + orthopyroxene + biotite and ubiquitous phenocryst disequilibrium textures. These magmas were likely stored in crustal reservoirs, where they experienced convection caused by mafic magma underplating, magma mixing, and/or assimilation. Trace element and mineral compositions of CBAF lavas provide evidence for complex evolution of distinct magma batches.

  2. Geometry and structure of the andesitic volcano-detritic deposits: The Merapi case

    Science.gov (United States)

    Selles, A.; Deffontaines, B.; Hendrayana, H.; Violette, S.

    2013-12-01

    Several geological studies have been performed on the volcano-detritic deposits but finally the global overview of the geometry of those is still poorly known. The quick alteration enhances the high heterogeneity of these formations, especially under tropical climate. Better knowledge of the structure of the volcano-sedimentary edifices is capital to understand:i) the geomorphological impacts, as landslides ii) or the hydrogeological processes. The Merapi Mount is an andesitic strato-volcano, located in Central Java and is one of the most active volcanoes in Indonesia. About 500,000 people live in the immediate vicinity of the volcano and are directly subject, not only to the volcanic eruptions but also to the landslide hazards. The East flank of the Merapi presents a complex history and has been relatively spared by the recent volcanic activity; thus, the geomorphology and the structure of the deposit have been driven by the erosion and remobilization processes under equatorial climate. This work contributes to understand the processes of construction, destruction and sedimentation of a complex active strato-volcano and shed light to its geological and geomorphological history. Based on field observations and literature, the specific deposits have been identified. The lithological facies have been described and several cross sections have been done to precise the distinct phases of building edifice, due to old eruptions. Recent field surveys allowed characterizing the dismantling steps and processes of the volcano by erosion and the local to distal sedimentation associated. The East flank has been split in four zones where each formation presents a lateral facies variation depending on the distance from the summit and the age of deposits. Based on the collected data, the size and the three dimensional extension of each deposits has been delimitated. The geological and geomorphological interpretation is proposed through a conceptual model.

  3. Terrain correction for gravity measurements, using a digital terrain model (DTM)

    NARCIS (Netherlands)

    Ketelaar, A.C.R.

    1987-01-01

    A single-term expression is given to calculate the gravitational effect for any square vertical prism with a sloping surface. A moderate measure of approximation is involved. The expression is well suited to automatic calculation of the terrain correction when a digital terrain model is available. T

  4. The toxic action of essential oils from Tephrosia purpurea on Rhizopertha dominica%灰毛豆精油对谷蠹的毒杀作用

    Institute of Scientific and Technical Information of China (English)

    李冠华; 王苏宁; 曾东强; 姚振威; 李有志

    2011-01-01

    In order to assess insecticidal activities of the essential oils from Tephrosiapurpurea leaves, T.purpurea barks and T.purpurea seeds against Rhizopertha dominica, the repellent, contact, fumigant and population inhibition toxicity of the three kinds of essential oils to R.dominica were determined respectively.The results showed: 1) Repellent rate reached to the maximum value with the corresponding repellency percentage of 82.3%, 90.7% and 94.3% after 48 h treatment; 2) All the three kinds of essential oils had exhibited contact toxicity against the 5-day old nymph of R.dominica after 24 h treatment, with the value of LD50 being 25.0, 27.9 and 27.8 mg/insect respectively; 3) Fumigant activity to the adult was examined after 48 hours' exposure to each of the three kinds of essential oils at the concentration of 10.0 g/m3; Their mortality ranged from 56.2% to 57.4%, and there was no significant difference among the mortality to the three kinds of essential oils; 4) At the dosage of 200 mg essential oils per 100 g paddy; the current population inhibition rate of the three kinds of essential oils against R.dominica population was 45.5%, 53.6% and 76.8%; F1 progeny population inhibition rate was 43.8%, 68.7% and 75.1%, and essential oils from the seeds exhibited more noted population inhibition activity than that of the other two kinds of essential oils.%为评价灰毛豆叶、树皮和种子精油对谷蠹的毒杀活性,分别测定了它们对谷蟗的驱避活性、触杀活性、熏蒸活性及种群抑制作用.结果表明,处理48 h后,3种精油对谷蠹成虫的驱避率达到最大值,分别是82.3%、90.7%和94.3%;3种精油都对谷蠹5日龄若虫具有触杀活性,其LD50值分别为每虫25.0、27.9和27.8 mg;在用量为20.0 mg/L时,3种精油对谷蠹成虫都具有熏蒸活性,熏蒸48 h后成虫的死亡率为56.2%~57.4%,3种精油的熏蒸活性无显著性差异;当100 g稻谷中拌有200 mg精油时,3种精油对当代

  5. Soft-electron beam and gamma-radiation sensitivity and DNA damage in phosphine-resistant and -susceptible strains of Rhyzopertha dominica.

    Science.gov (United States)

    Hasan, Md Mahbub; Todoriki, Setsuko; Miyanoshita, Akihiro; Imamura, Taro; Hayashi, Toru

    2006-10-01

    The soft-electron beam (low-energy electrons) and gamma-radiation sensitivities of phosphine-resistant (PHR) and -susceptible (PHS) strains of adults lesser grain borer Rhyzopertha dominica (F.) were studied, with particular reference to DNA damage assessed using single-cell electrophoresis (comet assay). Results showed that mortality in adult R. dominica varied significantly between both PHR and PHS strains. Adults of the PHR strain were found to be more tolerant toward soft-electron and gamma radiation than adults of the PHS strain. Studies on the longevity of strains showed that mean survival time and dose rate were highly correlated with both strains and treatments. Results also showed that adults of the PHR strain lived longer than adults of PHS strain for both treatments. Radiation sensitivity indices, however, decreased as radiation dose increased in both strains. Analysis of DNA damage, after 40- and 160-Gy gamma radiation, was carried out using cells obtained from both strains. Gamma-irradiated adults of both strains showed typical DNA fragmentation, compared with cells from nonirradiated adults, which showed more intact DNA. Investigations using the comet assay showed that tail length, moment, olive-tail moment, percentage of tail DNA, and percentage of DNA damage were all greater in the PHS strain compared with the PHR strain and the control insects. Results also showed that DNA damage remained at a constant level for up to 24 h after irradiation. The results have been discussed in relation to the observed strain differences in radiation sensitivity and resistance to phosphine.

  6. Controls on rind thickness on basaltic andesite clasts weathering in Guadeloupe

    Science.gov (United States)

    Sak, P.B.; Navarre-Sitchler, A. K.; Miller, C.E.; Daniel, C.C.; Gaillardet, J.; Buss, H.L.; Lebedeva, M.I.; Brantley, S.L.

    2010-01-01

    A clast of low porosity basaltic andesite collected from the B horizon of a soil developed on a late Quaternary volcaniclastic debris flow in the Bras David watershed on Basse-Terre Island, Guadeloupe, exhibits weathering like that observed in many weathered clasts of similar composition in other tropical locations. Specifically, elemental profiles measured across the core-rind interface document that primary minerals and glass weather to Fe oxyhydroxides, gibbsite and minor kaolinite in the rind. The earliest reaction identified in the core is oxidation of Fe in pyroxene but the earliest reaction that creates significant porosity is plagioclase dissolution. Elemental loss varies in the order Ca???Na>K???Mg>Si>Al>Fe???P??Ti, consistent with the relative reactivity of phases in the clast from plagioclase???pyroxene???glass>apatite>ilmenite. The rind surrounds a core of unaltered material that is more spherical than the original clast. The distance from the core-rind boundary to a visually prominent rind layer, L, was measured as a proxy for the rind thickness at 36 locations on a slab cut vertically through the nominal center of the clast. This distance averaged 24.4??3.1mm. Maximum and minimum values for L, 35.8 and 20.6mm, were observed where curvature of the core-rind boundary is greatest (0.12mm-1) and smallest (0.018mm-1) respectively. Extrapolating from other rinds in other locations, the rate of rind formation is estimated to vary by a factor of about 2 (from ~4 to 7??10-14ms-1) from low to high curvature. The observation of a higher rate of rind formation for a higher curvature interface is consistent with a diffusion-limited model for weathering rind formation. The diffusion-limited model predicts that, like rind thickness, values of the thickness of the reaction front (h) for a given reaction, defined as the zone over which a parent mineral such as plagioclase completely weathers to rind material, should also increase with curvature. Values of h were

  7. High-Mg andesites petrogenesis by amphibole crystallization and ultramafic crust assimilation

    Science.gov (United States)

    Tiepolo, M.; Tribuzio, R.; Langone, A.

    2009-12-01

    Mafic and ultramafic intrusives with high-Mg andesite (HMA) affinity are occasionally found in collisional settings. These amphibole-rich rocks preserve chemical and textural heterogeneities that are important records of the petrogenetic processes occurring in the deep portions of the arc crust. New insights on the origin of HMA are inferred from the Tertiary amphibole-rich ultramafic intrusives of the southern Adamello batholith (Italian Alps). These rocks consist of large amphibole grains with brown cores (Ti-pargasite) that progressively grade through brownish green (Mg-hornblende) and light green (edenite) rims. Brown amphibole has inclusions of olivine and clinopyroxene (±spinel) with irregular boundaries indicating disequilibrium with the host amphibole. Amphibole shows a marked chemical zoning. In particular, a decrease in Ti, HREE coupled to an increase in Mg, Ni, LREE, Th and U from the core to the rim is observed. Calculated equilibrium liquids for amphibole cores may be related to island arc basalts. On the other hand, liquids in equilibrium with amphibole rims share many compositional similarities to HMA (e.g. low HREE, strong LREE/HREE fractionation, high Th and U). According to the current knowledge of Amph/LD, a fractional crystallization process driven by amphibole may explain most of the observed elemental variations. However, the increase from core to rim of highly compatible elements in amphibole such as MgO and Ni contrasts with closed system fractional crystallization. The assimilation/resorption of olivine is considered the most efficient mechanism to supply or buffer MgO and Ni in the evolving system during amphibole crystallization. The textural disequilibrium of olivine with the host amphibole supports this process. In addition, clusters of olivine with triple junctions (Fo up to 85 mol%) and minor cpx were found in ultramafic rocks of the same complex. They probably represent fragments of older dunites/wehrlites dismembered by the

  8. An experimental investigation of high-temperature interactions between seawater and rhyolite, andesite, basalt and peridotite

    Science.gov (United States)

    Hajash, Andrew; Chandler, Gary W.

    1982-01-01

    Natural seawater was allowed to react with rhyolite, andesite, basalt, and peridotite at 200° 500° C, and 1,000 bars at water/rock mass ratios of 5 and 50 in order to investigate the effects of rock type, water/rock ratio, and temperature on solution chemistry and alteration mineralogy. The results indicate that interactions of seawater with various igneous rocks are similar in the production of a hydrous Mg-silicate and anhydrite as major alteration products. Fluids involved in the interactions lose Mg to alteration phases while leaching Fe, Mn, and Si from the rocks. The pH of the solutions is primarily controlled by Mg-OH-silicate formation and therefore varies with Mg and Si concentration of the system. Other reactions which involve Mg (such as Mg-Ca exchange) or which produce free H+, cause major differences in fluid chemistry between different seawater/ rock systems. High water/rock ratio systems (50/1) are generally more acidic and more efficient in leaching than low ratio systems (5/1), due to relatively more seawater Mg available for Mgsilicate production. The experiments show that large-scale seawater/rock interaction could exert considerable control on the chemistry of seawater, as well as producing large bodies of altered rock with associated ore-deposits. Active plate margins of convergence or divergence are suitable environments for hydrothermal systems due to the concurrence of igneous activity, tectonism, and a nearby water reservoir (seawater or connate water). The experimental data indicate that seawater interactions with igneous host rocks could generate many of the features of ore-deposits such as the Kuroko deposits of Japan, the Raul Mine of Peru, the Bleida deposit of Morocco, and deposits associated with ophiolites. Serpentinization of peridotite and alteration of igneous complexes associated with plate margins can also be explained by seawater interaction with the cooling rock. Geothermal energy production could benefit from experimental

  9. High performance robotic traverse of desert terrain.

    Energy Technology Data Exchange (ETDEWEB)

    Whittaker, William (Carnegie Mellon University, Pittsburgh, PA)

    2004-09-01

    This report presents tentative innovations to enable unmanned vehicle guidance for a class of off-road traverse at sustained speeds greater than 30 miles per hour. Analyses and field trials suggest that even greater navigation speeds might be achieved. The performance calls for innovation in mapping, perception, planning and inertial-referenced stabilization of components, hosted aboard capable locomotion. The innovations are motivated by the challenge of autonomous ground vehicle traverse of 250 miles of desert terrain in less than 10 hours, averaging 30 miles per hour. GPS coverage is assumed to be available with localized blackouts. Terrain and vegetation are assumed to be akin to that of the Mojave Desert. This terrain is interlaced with networks of unimproved roads and trails, which are a key to achieving the high performance mapping, planning and navigation that is presented here.

  10. Basalt-Limestone and Andesite-Limestone Interaction in the Arc Crust - Implications for Volcanic Degassing of CO2

    Science.gov (United States)

    Carter, L. B.; Dasgupta, R.

    2014-12-01

    Volcanically emitted CO2 is generally mantle-derived, but high degassing rates at some arcs (e.g. Merapi [1] and Colli Albani Volcanic District [2]) are thought to be affected by magma-carbonate interaction in the upper plate. However, the effects of depth, temperature, and composition on this process are poorly known. We experimentally simulated magma (50%)-limestone (50%) wallrock interactions at 0.5-1.0 GPa, 1100-1200 °C using pure calcite and a hydrous (~3-5 wt.% H2O) melt (basalt, andesite, or dacite). At 1.0 GPa, 1200 °C starting melts are superliquidus, whereas in the presence of calcite, Ca-rich cpx ± Ca-scapolite are produced. With increasing T, basalt-calcite interaction causes the melt, on a volatile-free basis, to become silica-poor and Ca-rich with alumina decreasing as cpx becomes more CaTs-rich. The same trend is seen with all starting melt compositions as P decreases at a constant T (1200 °C), producing melts similar to ultracalcic (CaO/Al2O3>>1) melt inclusions found in arc settings. Shifting from basalt to andesite has little effect on SiO2 and CaO of the reacted melt (e.g. 37 wt.% SiO2, 42 wt.% CaO at 0.5 GPa, 1200 °C), whereas Al2O3 of andesite-derived reacted melt is lower, likely a result of lower alumina in the starting andesite. Wall-rock calcite consumption is observed to increase with increasing T, decreasing P, and increasing melt XSiO2. At 0.5 GPa between 1100 and 1200 °C, our basalt experiments yield carbonate assimilation from 22 to 48 wt.%. This decreases to 20 wt.% at 1.0 GPa, 1200 °C, whereas an andesitic composition assimilates 59 to 52 wt.% from 0.5 to 1.0 GPa at 1200 °C. The higher assimilation in andesite-added runs at high-T is because of lower silicate liquidus as evidenced by lower modal proportion or absence of cpx ± scapolite. Using a magma flux rate estimated for Mt. Vesuvius [3], we obtain a CO2 outflux for a single such volcano experiencing arc magma-calcite reaction [4] of at least 2-4% of the present

  11. Geochemistry of Garibaldi Lake andesites and dacites indicates crustal contamination involved in formation of Northern Cascade arc lavas

    Science.gov (United States)

    Martindale, M.; Mullen, E.; Weis, D.

    2013-12-01

    The Cascade Arc presents a unique setting for studying the controls on andesite genesis and the implications for growth and evolution of the continental crust. It is the type-locality for a ';hot' subduction zone, where the downgoing slab is young and subduction is relatively slow. The northern segment of the Cascade arc, the Garibaldi Volcanic Belt (GVB), hosts the youngest subducting crust in Cascadia and the termination of the subducting slab. These conditions may affect magma generation processes by reducing the amount of water reaching the area of melt generation [1,2] and imparting an adakitic signature to magmas generated there if the slab edge melts [3]. We provide insights on the origin of andesites and dacites from the Garibaldi Lake area using new high-precision Pb, Sr, Nd, Hf isotope ratios and trace element data. Andesites and dacites from the Garibaldi Lake area (The Black Tusk, Mt. Price, and The Table) are calc-alkaline and show evidence for crustal contamination such as positive correlations between Ba/Nb and SiO2. Silica variation diagrams show no systematic trend for any of the volcanic centres, suggesting the presence of distinct magma batches. Garibaldi Lake andesites and dacites have among the least radiogenic Pb isotope ratios of all Cascade arc lavas, and define a linear array in Pb-isotope space. This most likely reflects mixing between MORB-source mantle (similar to Gorda and Explorer plate sources) and locally subducting sediments [4]. However, relative to GVB basalts and lavas from the rest of the Cascades (High Cascades), the andesites and dacites have higher 207Pb/204Pb (15.55-15.56) for a given 206Pb/204Pb (18.66-18.74). The Garibaldi Lake lavas also have higher 87Sr/86Sr (0.7033-0.7036) and lower ɛNd (5.8-7.9) at a given 206Pb/204Pb than GVB basalts and High Cascades lavas but among the highest ɛNd for a given SiO2 for the whole of the Cascades. ɛHf values (10.5-13.5) are higher at a given SiO2 value for Garibaldi Lake evolved

  12. Terrain Simplification Research in Augmented Scene Modeling

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    environment. As one of the most important tasks in augmented scene modeling, terrain simplification research has gained more and more attention. In this paper, we mainly focus on point selection problem in terrain simplification using triangulated irregular network. Based on the analysis and comparison of traditional importance measures for each input point, we put forward a new importance measure based on local entropy. The results demonstrate that the local entropy criterion has a better performance than any traditional methods. In addition, it can effectively conquer the "short-sight" problem associated with the traditional methods.

  13. Improved Inlet Conditions for Terrain CFD

    DEFF Research Database (Denmark)

    Pedersen, Jesper Grønnegaard

    The atmospheric boundary layer flow over different types of terrain is studied through simulations made with the finite volume CFD code of Ellipsys 2D and 3D. The simulations are compared to measurements made at the Høvsøre test site and over the hill of Askervein.The primary objective of these i......The atmospheric boundary layer flow over different types of terrain is studied through simulations made with the finite volume CFD code of Ellipsys 2D and 3D. The simulations are compared to measurements made at the Høvsøre test site and over the hill of Askervein.The primary objective...

  14. Investigation of Terrain Bounce Electronic Countermeasure

    Science.gov (United States)

    1980-12-01

    no point for which both the slope of the curve and the value of Vpd are equal to zero. (See Figure 5 for C -. 5.) Thus, there is no physical ...for rough terrain. A methodology was presented for solving the Terrain Bounce problem. In Section II1, the metho - dology was applied to a specific...Waves from Slightly Rough Surfaces", Communications on Pure Applied Mathematics , 4: 351-378 (1951). 22. Sherwood, E.M. and E.L. Ginzton. "Reflection

  15. Experimental insights into the formation of high-Mg basaltic andesites in the trans-Mexican volcanic belt

    Science.gov (United States)

    Weber, Rachel M.; Wallace, Paul J.; Dana Johnston, A.

    2012-05-01

    High-Mg basaltic andesites and andesites occur in the central trans-Mexican volcanic belt, and their primitive geochemical characteristics suggest equilibration with mantle peridotite. These lavas may represent slab melts that reequilibrated with overlying peridotite or hydrous partial melts of a peridotite source. Here, we experimentally map the liquidus mineralogy for a high-Mg basaltic andesite (9.6 wt% MgO, 54.4 wt% SiO2, Mg# = 75.3) as a function of temperature and H2O content over a range of mantle wedge pressures. Our results permit equilibration of this composition with a harzburgite residue at relatively high water contents (>7 wt%) and low temperatures (1,080-1,150°C) at 11-14 kbar. However, in contrast to the high Ni contents characteristic of olivine phenocrysts in many such samples from central Mexico, those of olivine phenocrysts in our sample are more typical of mantle melts that have fractionated a small amount of olivine. To account for this and the possibility that the refractory mantle source may have had olivine more Fo-rich than Fo90, we numerically evaluated alternative equilibration conditions, using our starting bulk composition adjusted to be in equilibrium with Fo92 olivine. This shifts equilibration conditions to higher temperatures (1,180-1,250°C) at mantle wedge pressures (11-15 kbar) for H2O contents (>3 wt%) comparable to those analyzed in olivine-hosted melt inclusions from this region. Comparison with geodynamic models shows that final equilibration occurred shallower than the peak temperature of the mantle wedge, suggesting that basaltic melts from the hottest part of the wedge reequilibrated with shallower mantle as they approached the Moho.

  16. Contemporaneous trachyandesitic and calc-alkaline volcanism of the Huerto Andesite, San Juan Volcanic Field, Colorado, USA

    Science.gov (United States)

    Parat, F.; Dungan, M.A.; Lipman, P.W.

    2005-01-01

    Locally, voluminous andesitic volcanism both preceded and followed large eruptions of silicic ash-flow tuff from many calderas in the San Juan volcanic field. The most voluminous post-collapse lava suite of the central San Juan caldera cluster is the 28 Ma Huerto Andesite, a diverse assemblage erupted from at least 5-6 volcanic centres that were active around the southern margins of the La Garita caldera shortly after eruption of the Fish Canyon Tuff. These andesitic centres are inferred, in part, to represent eruptions of magma that ponded and differentiated within the crust below the La Garita caldera, thereby providing the thermal energy necessary for rejuvenation and remobilization of the Fish Canyon magma body. The multiple Huerto eruptive centres produced two magmatic series that differ in phenocryst mineralogy (hydrous vs anhydrous assemblages), whole-rock major and trace element chemistry and isotopic compositions. Hornblende-bearing lavas from three volcanic centres located close to the southeastern margin of the La Garita caldera (Eagle Mountain - Fourmile Creek, West Fork of the San Juan River, Table Mountain) define a high-K calc-alkaline series (57-65 wt % SiO2) that is oxidized, hydrous and sulphur rich. Trachyandesitic lavas from widely separated centres at Baldy Mountain-Red Lake (western margin), Sugarloaf Mountain (southern margin) and Ribbon Mesa (20 km east of the La Garita caldera) are mutually indistinguishable (55-61 wt % SiO2); they are characterized by higher and more variable concentrations of alkalis and many incompatible trace elements (e.g. Zr, Nb, heavy rare earth elements), and they contain anhydrous phenocryst assemblages (including olivine). These mildly alkaline magmas were less water rich and oxidized than the hornblende-bearing calc-alkaline suite. The same distinctions characterize the voluminous precaldera andesitic lavas of the Conejos Formation, indicating that these contrasting suites are long-term manifestations of San Juan

  17. Geochemistry of the high-Mg andesites at Zhangwu, western Liaoning: Implication for delamination of newly formed lower crust

    Institute of Scientific and Technical Information of China (English)

    HUANG; Hua; GAO; Shan; HU; ZhaoChu; LIU; XiaoMing; YUAN; HongLing

    2007-01-01

    Ten volcanic samples at Zhangwu, western Liaoning Province, North China were selected for a systematic geochemical, mineralogical and geochronological study, which provides an opportunity to explore the interaction between the continental crust and mantle beneath the north margin of the North China craton. Except one basalt sample (SiO2= 50.23%), the other nine samples are andesitic with SiO2 contents ranging from 53% to 59%. They have relatively high MgO (3.4%-6.1%, Mg#=50-64) and Ni and Cr contents (Ni 27×10-6-197×10-6, Cr 51×10-6-478×10-6). Other geochemical characteristics of Zhangwu high-Mg andesites (HMAs) include strong fractionation of light rare earth elements (LREE) from heavy rare earth elements (HREE), and Sr from Y, with La/Yb greater than 15, and high Sr/Y (34-115). Zircons of andesite YX270 yield three age groups with no Precambrian age, which precludes origin of the Zhangwu HMAs from the partial melting of the Precambrian crust. The oldest age group peaking at 253 Ma is interpreted to represent the collision of the Siberia block and the North China block, resulting in formation of the Central Asian orogenic belt by closure of the Mongol-Okhotsk Ocean. The intermediate age group corresponds to the basalt underplating which caused the widespread coeval granitoids in the North China craton with a peak 206Pb/238U age of 172 Ma. The youngest age group gives a 206Pb/238U age of 126±2 Ma, which is interpreted as the eruption age of the Zhangwu HMAs. The high 87Sr/86Sri(126 Ma)>0.706 and low -Nd(t)= -6.36--13.99 of the Zhangwu HMAs are distinct from slab melts. The common presence of reversely zoned clinopyroxene phenocrysts in the Zhangwu HMAs argues against the origin of the Zhangwu HMAs either from melting of the water saturated mantle or melting of the lower crust. In light of the evidence mentioned above, the envisaged scenario for the formation of the Zhangwu HMAs is related to the basaltic underplating at the base of the crust, which led to

  18. Rhyolitic calderas and centers clustered within the active andesitic belt of Ecuador's Eastern Cordillera

    Energy Technology Data Exchange (ETDEWEB)

    Mothes, Patricia A; Hall, Minard L [Instituto Geofisico, Escuela Politecnica Nacional, Quito (Ecuador)], E-mail: pmothes@igepn.edu.ec

    2008-10-01

    In the Ecuadorian volcanic arc a cluster of scattered rhyolitic and dacitic centers within the mainly andesitic Eastern Cordillera includes large caldera structures (Chalupas, Chacana, Cosanga) as well as smaller edifices, built upon the Paleozoic-Mesozoic metamorphic basement. At the Chacana caldera magmatism dates from 2.7 Ma to historic times. These centers erupted enormous ash flows and thick pumice lapilli falls that covered the InterAndean Valley near Quito. The role of the 50-70 km-thick crust with a notable negative gravity anomaly appears to be related to the generation of this highly silicic magmatism occurring along the crest of the Andes in the NVZ.

  19. Phenocryst complexity in andesites and dacites from the Tequila volcanic field, Mexico: resolving the effects of degassing vs. magma mixing

    Science.gov (United States)

    Frey, Holli M.; Lange, Rebecca A.

    2011-08-01

    The petrology of five phenocryst-poor (2-5%) andesites and dacites, all of which were erupted from different short-lived, monogenetic vents, is compared to that of phenocryst-rich (10-25%) andesites erupted from the adjacent stratovolcano, Volcán Tequila, in the Mexican arc. Despite differences in phenocryst abundances, these magmas have comparable phase assemblages (plagioclase + orthopyroxene + titanomagnetite + ilmenite + apatite ± augite ± hornblende), and similarly wide variations in phenocryst compositions, coupled to complex zoning patterns. For the phenocryst-poor lavas, equilibrium pairs of two Fe-Ti oxides lead to a narrow range of calculated temperatures for each sample that range from 934 (±24) to 1,073 (±6)°C and oxygen fugacities that range from +0.1 to +0.7 log units relative to the Ni-NiO buffer. Application of the plagioclase-liquid hygrometer to each sample at these calculated temperatures leads to maximum melt water concentrations of 4.6-3.1 wt% during plagioclase crystallization, indicating that the magmas were fluid saturated at depths ≥6.4-4.5 km. There is a wide, continuous range in the composition of plagioclase (≤44 mol% An) and orthopyroxene (≤16% Mg#) phenocrysts in each sample, which is consistent with a loss of dissolved water (≤2.8 wt%) from the melt phase during degassing as the magmas ascended rapidly to the surface. Evidence is presented that shows the effect of dissolved water is to reduce the activity of MgO relative to FeO in the melt phase, which indicates that degassing will also affect the Mg# of pyroxene phenocrysts, with higher melt water concentrations favoring Fe-rich pyroxene. Both plagioclase and orthopyroxene commonly display diffusion-limited growth textures (e.g., skeletal and hopper crystals, large interior melt hollows, and swallow tails), which are consistent with large undercoolings produced by degassing-induced crystallization. Therefore, degassing is proposed as a possible cause for the phenocryst

  20. 轻钢屋面房式仓散装粮堆局部谷蠹的熏蒸处理试验%FUMIGATION TREATMENT TEST ON RHIZOPERTHA DOMINICA OF LOCAL GRAIN BULKS IN LIGHT-STEEL ROOFING WAREHOUSE

    Institute of Scientific and Technical Information of China (English)

    汪保良; 刘磊; 王光跃; 潘中华; 乔占民; 徐晓娟

    2012-01-01

    In view of poor air tightness of light-steel roofing bulk warehouse and the difficulty to fumigate locally occurred Rhizopertha dominica. Applying pesticide by taking probes localy combination with burying small bags at the upper layer of stored grain, sealing grain surface with film, stopping circulation in warehouse, make the PH3 concentration be kept over 300 mL/m3 for 25 d in local occurenece of Rhizopertha dominica, and then achieved the effect of killing Rhizopertha dominica thoroughly.%针对轻钢屋面散装房式仓气密性差、局部发生谷蠹时熏杀难度大的问题,采取局部打探管投药与整仓粮堆上层小布袋埋藏法投药相结合,粮面覆膜密闭,不再进行整仓环流,以保证局部谷蠹发生区域PH3浓度保持在300mL/m3以上25 d,可以达到彻底杀死谷蠹的效果.

  1. Chronology of heavily cratered terrains on Mercury

    Science.gov (United States)

    Marchi, S.; Chapman, C. R.

    2012-12-01

    Imaging of Mercury by Mariner 10 revealed a planet with more extensive plains units than on the Moon. Even in heavily cratered terrain, there is a lack of craters Morbidelli et al., [1] in order to interpret new crater counts on these terrains. We find that these craters are probably not saturated but may have been in equilibrium with a rapid resurfacing process, presumably volcanism that formed the earliest recognized intercrater plains. The crater retention age for this terrain, which contains the oldest large craters on Mercury, is surprisingly young, perhaps hundreds of millions of years younger than the heavily cratered pre-Nectarian terrains on the Moon [2]. These results are important for understanding the early geological and geophysical evolution of Mercury. References: [1] Morbidelli A., Marchi S., Bottke W.F., and Kring D.A. 2012. A sawtooth timeline for the first billion years of the lunar bombardment. Earth and Planetary Science Letters, in press. [2] Marchi S., Bottke W.F., Kring D.A., and Morbidelli A. 2012. The onset of the lunar cataclysm as recorded in its ancient crater populations. Earth and Planetary Science Letters 325, 27-38.

  2. Processes Modifying Cratered Terrains on Pluto

    Science.gov (United States)

    Moore, J. M.

    2015-01-01

    The July encounter with Pluto by the New Horizons spacecraft permitted imaging of its cratered terrains with scales as high as approximately 100 m/pixel, and in stereo. In the initial download of images, acquired at 2.2 km/pixel, widely distributed impact craters up to 260 km diameter are seen in the near-encounter hemisphere. Many of the craters appear to be significantly degraded or infilled. Some craters appear partially destroyed, perhaps by erosion such as associated with the retreat of scarps. Bright ice-rich deposits highlight some crater rims and/or floors. While the cratered terrains identified in the initial downloaded images are generally seen on high-to-intermediate albedo surfaces, the dark equatorial terrain informally known as Cthulhu Regio is also densely cratered. We will explore the range of possible processes that might have operated (or still be operating) to modify the landscape from that of an ancient pristinely cratered state to the present terrains revealed in New Horizons images. The sequence, intensity, and type of processes that have modified ancient landscapes are, among other things, the record of climate and volatile evolution throughout much of the Pluto's existence. The deciphering of this record will be discussed. This work was supported by NASA's New Horizons project.

  3. Wind turbine wake measurement in complex terrain

    DEFF Research Database (Denmark)

    Hansen, Kurt Schaldemose; Larsen, Gunner Chr.; Menke, Robert;

    2016-01-01

    SCADA data from a wind farm and high frequency time series measurements obtained with remote scanning systems have been analysed with focus on identification of wind turbine wake properties in complex terrain. The analysis indicates that within the flow regime characterized by medium to large...

  4. Modelling Canopy Flows over Complex Terrain

    Science.gov (United States)

    Grant, Eleanor R.; Ross, Andrew N.; Gardiner, Barry A.

    2016-06-01

    Recent studies of flow over forested hills have been motivated by a number of important applications including understanding CO_2 and other gaseous fluxes over forests in complex terrain, predicting wind damage to trees, and modelling wind energy potential at forested sites. Current modelling studies have focussed almost exclusively on highly idealized, and usually fully forested, hills. Here, we present model results for a site on the Isle of Arran, Scotland with complex terrain and heterogeneous forest canopy. The model uses an explicit representation of the canopy and a 1.5-order turbulence closure for flow within and above the canopy. The validity of the closure scheme is assessed using turbulence data from a field experiment before comparing predictions of the full model with field observations. For near-neutral stability, the results compare well with the observations, showing that such a relatively simple canopy model can accurately reproduce the flow patterns observed over complex terrain and realistic, variable forest cover, while at the same time remaining computationally feasible for real case studies. The model allows closer examination of the flow separation observed over complex forested terrain. Comparisons with model simulations using a roughness length parametrization show significant differences, particularly with respect to flow separation, highlighting the need to explicitly model the forest canopy if detailed predictions of near-surface flow around forests are required.

  5. Conically scanning lidar error in complex terrain

    DEFF Research Database (Denmark)

    Bingöl, Ferhat; Mann, Jakob; Foussekis, Dimitri

    2009-01-01

    Conically scanning lidars assume the flow to be homogeneous in order to deduce the horizontal wind speed. However, in mountainous or complex terrain this assumption is not valid implying a risk that the lidar will derive an erroneous wind speed. The magnitude of this error ismeasured by collocating...

  6. Scaling Terrain Attributes By Fractal Methods

    Science.gov (United States)

    Terrain attributes derived from grid digital elevation models (DEMs) are commonly used in distributed hydrologic models. However, many attribute estimations are biased by DEM grid cell size. For example, land surface slopes estimated from 30-m DEMs are, on average, less than slopes estimated from ...

  7. Terrain Measurement with SAR/InSAR

    Science.gov (United States)

    Li, Deren; Liao, Mingsheng; Balz, Timo; Zhang, Lu; Yang, Tianliang

    2016-08-01

    Terrain measurement and surface motion estimation are the most important applications for commercial and scientific SAR missions. In Dragon-3, we worked on these applications, especially regarding DEM generation, surface motion estimation with SAR time- series for urban subsidence monitoring and landslide motion estimation, as well as developing tomographic SAR processing methods in urban areas.

  8. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten;

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present ...

  9. Tessera terrain: Characteristics and models of origin

    Science.gov (United States)

    Bindschadler, D. L.; Head, James W.

    1989-01-01

    Tessera terrain consists of complexly deformed regions characterized by sets of ridges and valleys that intersect at angles ranging from orthogonal to oblique, and were first viewed in Venera 15/16 SAR data. Tesserae cover more area (approx. 15 percent of the area north of 30 deg N) than any of the other tectonic units mapped from the Venera data and are strongly concentrated in the region between longitudes 0 deg E and 150 deg E. Tessera terrain is concentrated between a proposed center of crustal extension and divergence in Aphrodite and a region of intense deformation, crustal convergence, and orogenesis in western Ishtar Terra. Thus, the tectonic processes responsible for tesserae are an important part of Venus tectonics. As part of an effort to understand the formation and evolution of this unusual terrain type, the basic characteristics of the tesserae were compared to the predictions made by a number of tectonic models. The basic characteristics of tessera terrain are described and the models and some of their basic predictions are briefly discussed.

  10. Modelling Canopy Flows over Complex Terrain

    Science.gov (United States)

    Grant, Eleanor R.; Ross, Andrew N.; Gardiner, Barry A.

    2016-12-01

    Recent studies of flow over forested hills have been motivated by a number of important applications including understanding CO_2 and other gaseous fluxes over forests in complex terrain, predicting wind damage to trees, and modelling wind energy potential at forested sites. Current modelling studies have focussed almost exclusively on highly idealized, and usually fully forested, hills. Here, we present model results for a site on the Isle of Arran, Scotland with complex terrain and heterogeneous forest canopy. The model uses an explicit representation of the canopy and a 1.5-order turbulence closure for flow within and above the canopy. The validity of the closure scheme is assessed using turbulence data from a field experiment before comparing predictions of the full model with field observations. For near-neutral stability, the results compare well with the observations, showing that such a relatively simple canopy model can accurately reproduce the flow patterns observed over complex terrain and realistic, variable forest cover, while at the same time remaining computationally feasible for real case studies. The model allows closer examination of the flow separation observed over complex forested terrain. Comparisons with model simulations using a roughness length parametrization show significant differences, particularly with respect to flow separation, highlighting the need to explicitly model the forest canopy if detailed predictions of near-surface flow around forests are required.

  11. Declarative terrain modeling for military training games

    NARCIS (Netherlands)

    Smelik, R.M.; Tutenel, T.; Kraker, J.K.. de; Bidarra, R.

    2010-01-01

    Military training instructors increasingly often employ computer games to train soldiers in all sorts of skills and tactics. One of the difficulties instructors face when using games as a training tool is the creation of suitable content, including scenarios, entities, and corresponding terrain mode

  12. Soluble iron inputs to the Southern Ocean through recent andesitic to rhyolitic volcanic ash eruptions from the Patagonian Andes

    Science.gov (United States)

    Simonella, L. E.; Palomeque, M. E.; Croot, P. L.; Stein, A.; Kupczewski, M.; Rosales, A.; Montes, M. L.; Colombo, F.; García, M. G.; Villarosa, G.; Gaiero, D. M.

    2015-08-01

    Patagonia, due to its geographic position and the dominance of westerly winds, is a key area that contributes to the supply of nutrients to the Southern Ocean, both through mineral dust and through the periodic deposits of volcanic ash. Here we evaluate the characteristics of Fe dissolved (into soluble and colloidal species) from volcanic ash for three recent southern Andes volcanic eruptions having contrasting features and chemical compositions. Contact between cloud waters (wet deposition) and end-members of andesitic (Hudson volcano) and rhyolitic (Chaitén volcano) materials was simulated. Results indicate higher Fe release and faster liberation rates in the andesitic material. Fe release during particle-seawater interaction (dry deposition) has higher rates in rhyolitic-type ashes. Rhyolitic ashes under acidic conditions release Fe in higher amounts and at a slower rate, while in those samples containing mostly glass shards, Fe release was lower and faster. The 2011 Puyehue eruption was observed by a dust monitoring station. Puyehue-type eruptions can contribute soluble Fe to the ocean via dry or wet deposition, nearly reaching the limit required for phytoplankton growth. In contrast, the input of Fe after processing by an acidic eruption plume could raise the amount of dissolved Fe in surface ocean waters several times, above the threshold required to initiate phytoplankton blooms. A single eruption like the Puyehue one represents more than half of the yearly Fe flux contributed by dust.

  13. Traversable Terrain Modeling and Performance Measurement of Mobile Robots

    Science.gov (United States)

    2004-08-01

    In this paper, we have described a technique for terrain traversability assessment modeling of mobile robots operating in natural terrain and...presented a fast near-optimum algorithm for autonomous navigational path planning of mobile robots in rough terrain environments. The proposed method is

  14. Large Terrain Continuous Level of Detail 3D Visualization Tool

    Science.gov (United States)

    Myint, Steven; Jain, Abhinandan

    2012-01-01

    This software solved the problem of displaying terrains that are usually too large to be displayed on standard workstations in real time. The software can visualize terrain data sets composed of billions of vertices, and can display these data sets at greater than 30 frames per second. The Large Terrain Continuous Level of Detail 3D Visualization Tool allows large terrains, which can be composed of billions of vertices, to be visualized in real time. It utilizes a continuous level of detail technique called clipmapping to support this. It offloads much of the work involved in breaking up the terrain into levels of details onto the GPU (graphics processing unit) for faster processing.

  15. Efeito de repelência do inseticida deltamethrin sobre insetos de raças resistentes e suscetíveis de Rhyzopertha dominica (F. (Coleoptera, Bostrichidae em grãos de trigo armazenado Repellency of deltamethrin against resistant and susceptible insects of strains of Rhyzopertha dominica (F. (Coleoptera, Bostrichidae in stored wheat

    Directory of Open Access Journals (Sweden)

    Helenara Beckel

    2005-12-01

    Full Text Available Rhyzopertha dominica (F. foi submetida a estudos de repelência ao inseticida deltamethrin aplicado em grãos de trigo, em laboratório. Foram testadas quatro raças de R. dominica, duas resistentes ao deltamethrin, BR6 e BR12, e duas suscetíveis, BR4 e UK1, coletadas em unidades armazenadoras de grãos e mantidas em multiplicação em laboratório. O experimento foi realizado em quatro repetições, liberando-se 100 insetos, por repetição, em um pote de plástico contendo grãos de trigo não tratados; esse pote ficava conectado a outro de mesmo tamanho contendo grãos de trigo tratados com CL5, CL25 e CL50 do inseticida deltamethrin, separadamente, para cada raça. O conjunto foi mantido na posição horizontal, de forma a permitir a livre passagem dos insetos entre os dois compartimentos, a 25±1ºC e 60±5% de temperatura e de umidade relativa do ar, respectivamente. A avaliação da distribuição dos insetos no interior dos potes ocorreu 12 dias após sua liberação. Os insetos evitaram os grãos tratados com todas as concentrações de deltamethrin, indicando o efeito de repelência que o inseticida exerce sobre eles. No caso das raças suscetíveis, a diferença não foi significativa entre o número de indivíduos nas porções tratadas e não tratadas, nas diferentes concentrações. Por outro lado, os indivíduos das raças resistentes apresentaram um comportamento de repelência significativamente mais acentuado que os das suscetíveis, especialmente nas concentrações mais elevadas. O estudo dessas respostas comportamentais é fundamental para a tomada de decisões em programas de manejo da resistência de insetos de produtos armazenados.This research was carried out in order to study the effect of repellency of the insecticide deltamethrin against the lesser grain borer, Rhyzopertha dominica (F.. Four strains of R. dominica were used: two of them were deltamethrin resistant, BR6 and BR12, and two were susceptible, BR4 and UK1

  16. Morpho-tectonics and mechanism of emplacement of the andesitic ring in Givshad, east of Iran

    Science.gov (United States)

    Khatib, M. M.; Zarrinkoub, M. H.

    2009-04-01

    matter of debate for a considerable period of time. However, the mechanism for is emplacement still remains an enigma. A large quantity of geological information, maps, field data have become available over the last 30 years. The Eocene Givshad volcanism intruded into the Paleocene flysch type sediments. These flysch sediments are deposited over an ophiolite mélange sequence in south of Birjand, east of Iran. This ophiolite mélange is introduced as cretaceous sequence. A transperssional tectonic regime case emplacement the oceanic lithosphere segments over continental margin by in upper cretaceous-early tertiary. Some local shear zones with E-W general trends have occurred during emplacement period. Shear zones reactivation happen after Paleocene flysch type sedimentation. These processes have created three different types of deep open spaces. Rhomboid, lensoidal and wedge shape spaces made deep conduits in crustal shear zones. Two large-size ring-like structures were investigated in Givshad area. The size of ring-like structures are variable and ranges from 1×1.5 km to 0.9 × 1.2 Km. Based on the field structural data, vertical cross section of maps and morphotectonic evidences these structure aren't ring sill or dykes. They should be collapsed structure of andesitic dome ascending and it looks as a caldera. The formations of these calderas are classically ascribed to the vertical collapse of the overlying roof during emptying of a shallow magma chamber. This vertical collapse occurs along a ring fault system and leaves a vast, circular and flat-lying depression limited by sub-vertical cliffs that can reach several ten meters high. The walls of ring-like structure have been affected by systematic shear joints. Crossed joints prepare a background for wethering and alteration inside the ring. Key words: ring-like structures, collapse, Givshad area, morphotectonic, transperssional

  17. Study on robust terrain following control

    Institute of Scientific and Technical Information of China (English)

    Zha Xu; Cui Pingyuan

    2005-01-01

    Based on classical terrain following (TF) algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from Digital Elevation Map (DEM) for TF control is discussed in order to save store space. The block control model, which is suitable for backstepping design,is given for nonlinear model of aircraft. Making full use of the characteristics of the system and combining block control principle, backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors converge to the neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the aircraft model are presented to demonstrate the effectiveness of the proposed control law.

  18. Application of Digital Terrain Model to volcanology

    Directory of Open Access Journals (Sweden)

    V. Achilli

    2006-06-01

    Full Text Available Three-dimensional reconstruction of the ground surface (Digital Terrain Model, DTM, derived by airborne GPS photogrammetric surveys, is a powerful tool for implementing morphological analysis in remote areas. High accurate 3D models, with submeter elevation accuracy, can be obtained by images acquired at photo scales between 1:5000-1:20000. Multitemporal DTMs acquired periodically over volcanic area allow the monitoring of areas interested by crustal deformations and the evaluation of mass balance when large instability phenomena or lava flows have occurred. The work described the results obtained from the analysis of photogrammetric data collected over the Vulcano Island from 1971 to 2001. The data, processed by means of the Digital Photogrammetry Workstation DPW 770, provided DTM with accuracy ranging between few centimeters to few decimeters depending on the geometric image resolution, terrain configuration and quality of photographs.

  19. Contortionist bubbles in andesitic enclaves: implications for gas migration and phase segregation in crystal-rich magmas.

    Science.gov (United States)

    Oppenheimer, J. C.; Cashman, K. V.; Rust, A.; Dobson, K. J.; Bacon, C. R.; Dingwell, D. B.

    2016-12-01

    In order to constrain gas migration behaviors in crystal-rich magmas, we compare results of analogue experiments to frozen structures in andesitic enclaves. In the analogue experiments air was injected into mixtures of syrup and particles sandwiched between glass plates. We observed a significant increase in bubble deformation and coalescence when particle fractions increased beyond a critical value (the random loose packing). At high particle fractions, bubble growth re-organized (compacted) the particles adjacent to the bubble walls. This caused liquid segregation into patches within the particle suspension and into large void spaces near the outer edge of experiments. We compare these experiments to void morphologies in a 58 x 70 x 73 cm andesitic enclave from silicic-andesite lava flows of Mt Mazama, Oregon (Bacon, 1986). This enclave is zoned, with a vesicle-rich center and a glass-rich rim, suggesting gas-driven melt segregation from the center to the rim. We use both 2D (optical microscopy and SEM) and 3D (X-ray tomography) techniques to image crystal textures and bubble shapes. The center of the enclave bears scattered patches of groundmass in the main phenocryst framework. These patches are similar to those observed in experiments, and thus melt segregation in the enclave may have occurred both toward the rim and toward these patches. Bubble morphologies reveal two main types of bubbles. (1) Lobate and finger-like bubbles, similar to the deformed bubbles in experiments, are found exclusively in the groundmass patches. They are also often associated with compacted crystal structures at the bubble walls. (2) Diktytaxitic textures - angular bubbles flattened against phenocrysts - are abundant in the crystal networks. These voids are entirely connected in 3D and formed the gas-rich center of the enclave. They likely represent a gas migration regime where the expanding gas front cannot deform the crystal structure but instead invades the pore-space between

  20. Visual Media Reasoning - Terrain-based Geolocation

    Science.gov (United States)

    2015-06-01

    silhouette has been computed for a pixel, the signatures is computed. The details of the GPU kernel and the mathematics pertinent to the extraction of the...system software for large-scale pattern matching. The technologies offer many promising benefits in a variety of fields that rely on pattern...representation of terrain silhouettes. In Proceedings of the 13th annual ACM international workshop on Geographic information systems, GIS ’05, pages

  1. Mobility versus terrain: a game theoretic approach

    Science.gov (United States)

    Bednarz, David; Muench, Paul

    2016-05-01

    Mobility and terrain are two sides of the same coin. You cannot describe mobility unless you describe the terrain. For example, if my world is trench warfare, the tank may be the ideal vehicle. If my world is urban warfare, clearing buildings and such, the tank may not be an ideal vehicle, perhaps an anthropomorphic robot would be better. We seek a general framework for mobility that captures the relative value of different mobility strategies. Game theory is positively the right way to analyze the interactions of rational players who behave strategically. In this paper, we will describe the interactions between a mobility player, who is trying to make it from point A to point B with one chance to refuel, and a terrain player who is trying to minimize that probability by placing an obstacle somewhere along the path from A to B. In previous work [1], we used Monte Carlo methods to analyze this mobility game, and found optimal strategies for a discretized version of the game. Here we show the relationship of this game to a classic game of timing [2], and use solution methods from that literature to solve for optimal strategies in a continuous version of this mobility game.

  2. Cooperative terrain model acquisition by two point-robots in planar polygonal terrains

    Energy Technology Data Exchange (ETDEWEB)

    Rao, N.S.V.; Protopopescu, V.

    1994-11-29

    We address the model acquisition problem for an unknown terrain by a team of two robots. The terrain may be cluttered by a finite number of polygonal obstacles with unknown shapes and positions. The robots are point-sized and equipped with visual sensors which acquire all visible parts of the terrain by scanning from their locations. The robots communicate with each other via wireless connection. The performance is measured by the number of the sensor (scan) operations which are assumed to be the most time-consuming/expensive of all the robot operations. We employ the restricted visibility graph methods in a hierarchiacal setup. For terrains with convex obstacles, the sensing time can be halved compared to a single robot implementation. For terrains with concave corners, the performance of the algorithm depends on the number of concave regions and their depths. A hierarchical decomposition of the restricted visibility graph into 2-connected components and trees is considered. Performance for the 2-robot team is expressed in terms of sizes of 2-connected components, and the sizes and diameters of the trees. The proposed algorithm and analysis can be applied to the methods based on Voronoi diagram and trapezoidal decomposition.

  3. The rph1 gene is a common contributor to the evolution of phosphine resistance in independent field isolates of Rhyzopertha dominica.

    Science.gov (United States)

    Mau, Yosep S; Collins, Patrick J; Daglish, Gregory J; Nayak, Manoj K; Pavic, Hervoika; Ebert, Paul R

    2012-01-01

    Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks.

  4. The rph1 gene is a common contributor to the evolution of phosphine resistance in independent field isolates of Rhyzopertha dominica.

    Directory of Open Access Journals (Sweden)

    Yosep S Mau

    Full Text Available Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks.

  5. The rph1 Gene Is a Common Contributor to the Evolution of Phosphine Resistance in Independent Field Isolates of Rhyzopertha Dominica

    Science.gov (United States)

    Mau, Yosep S.; Collins, Patrick J.; Daglish, Gregory J.; Nayak, Manoj K.; Pavic, Hervoika; Ebert, Paul R.

    2012-01-01

    Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks. PMID:22363668

  6. Using a partial sum method and GPS tracking data to identify area restricted search by artisanal fishers at moored fish aggregating devices in the Commonwealth of Dominica.

    Science.gov (United States)

    Alvard, Michael; Carlson, David; McGaffey, Ethan

    2015-01-01

    Foragers must often travel from a central place to exploit aggregations of prey. These patches can be identified behaviorally when a forager shifts from travel to area restricted search, identified by a decrease in speed and an increase in sinuosity of movement. Faster, more directed movement is associated with travel. Differentiating foraging behavior at patches from travel to patches is important for a variety of research questions and has now been made easier by the advent of small, GPS devices that can track forager movement with high resolution. In the summer and fall of 2012, movement data were collected from GPS devices placed on foraging trips originating in the artisanal fishing village of Desa Ikan (pseudonym), on the east coast of the Caribbean island nation of the Commonwealth Dominica. Moored FADs are human-made structures anchored to the ocean floor with fish attraction material on or near the surface designed to effectively create a resource patch. The ultimate goal of the research is to understand how property rights are emerging after the introduction of fish aggregating device (FAD) technology at the site in 1999. This paper reports on research to identify area-restricted search foraging behavior at FAD patches. For 22 foraging trips simultaneous behavioral observations were made to ground-truth the GPS movement data. Using a cumulative sum method, area restricted search was identified as negative deviations from the mean travel speed and the method was able to correctly identify FAD patches in every case.

  7. Analysis of noise pollution in an andesite quarry with the use of simulation studies and evaluation indices.

    Science.gov (United States)

    Kosała, Krzysztof; Stępień, Bartłomiej

    2016-01-01

    This paper presents the verification of two partial indices proposed for the evaluation of continuous and impulse noise pollution in quarries. These indices, together with the sound power of machines index and the noise hazard index at the workstation, are components of the global index of assessment of noise hazard in the working environment of a quarry. This paper shows the results of acoustic tests carried out in an andesite quarry. Noise generated by machines and from performed blasting works was investigated. On the basis of acoustic measurements carried out in real conditions, the sound power levels of machines and the phenomenon of explosion were determined and, based on the results, three-dimensional models of acoustic noise propagation in the quarry were developed. To assess the degree of noise pollution in the area of the quarry, the continuous and impulse noise indices were used.

  8. Crystallization of oxidized, moderately hydrous arc basalt at mid- to lower-crustal pressures: Implications for andesite genesis

    Science.gov (United States)

    Blatter, Dawnika L.; Sisson, Thomas W.; Hankins, W. Ben

    2013-01-01

    This study focuses on the production of convergent margin calc-alkaline andesites by crystallization–differentiation of basaltic magmas in the lower to middle crust. Previous experimental studies show that dry, reduced, subalkaline basalts differentiate to tholeiitic (high Fe/Mg) daughter liquids, but the influences of H2O and oxidation on differentiation are less well established. Accordingly, we performed crystallization experiments at controlled oxidized fO2 (Re–ReO2 ≈ ΔNi–NiO + 2) on a relatively magnesian basalt (8.7 wt% MgO) typical of mafic magmas erupted in the Cascades near Mount Rainier, Washington. The basalt was synthesized with 2 wt% H2O and run at 900, 700, and 400 MPa and 1,200 to 950 °C. A broadly clinopyroxenitic crystallization interval dominates near the liquidus at 900 and 700 MPa, consisting of augite + olivine + orthopyroxene + Cr-spinel (in decreasing abundance). With decreasing temperature, plagioclase crystallizes, Fe–Ti-oxide replaces spinel, olivine dissolves, and finally amphibole appears, producing gabbroic and then amphibole gabbroic crystallization stages. Enhanced plagioclase stability at lower pressure narrows the clinopyroxenitic interval and brings the gabbroic interval toward the liquidus. Liquids at 900 MPa track along Miyashiro’s (Am J Sci 274(4):321–355, 1974) tholeiitic versus calc-alkaline boundary, whereas those at 700 and 400 MPa become calc-alkaline at silica contents ≥56 wt%. This difference is chiefly due to higher temperature appearance of magnetite (versus spinel) at lower pressures. Although the evolved liquids are similar in many respects to common calc-alkaline andesites, the 900 and 700 MPa liquids differ in having low CaO concentrations due to early and abundant crystallization of augite, with the result that those liquids become peraluminous (ASI: molar Al/(Na + K + 2Ca) > 1) at ≥61 wt% SiO2, similar to liquids reported in other studies of the high-pressure crystallization of hydrous basalts

  9. Origin of co-existing basalts, high-Mg andesites, and adakites in the SW Japan hot subduction system

    Science.gov (United States)

    Kimura, J.; Kunikiyo, T.; Osaka, I.; Shimoshioiri, Y.; Katakuse, M.; Kakubuchi, S.; Nagao, T.; Furuyama, K.; Kamei, A.; Nakajima, J.; Stern, R. J.; Gill, J. B.

    2012-12-01

    In response to subduction of the young, hot Shikoku Basin of the Philippine Sea Plate (PSP) slab, arc magmas have been active throughout the late Cenozoic (high-Mg andesites (HMAs), and adakitic andesites and dacites. The OIB-type basalts preceded the arc-type magmas. Therefore, the transition from OIB- to arc-types was related to opening of the Japan of Sea back-arc basin and subsequent re-initiation of PSP subduction. However, both the origin and tectonic implications of this magmatism are debated. Consequently, we analyzed the bulk rock geochemistry of 340 lava samples from seven Quaternary volcanoes and investigated their sources and melting conditions using a geochemical mass balance model, Arc Basalt Simulator version 4 (ABS4). Comparison to basement granitoids precludes adakite genesis in the lower crust. Instead, the ABS4 model suggests that the adakites are mostly slab melts plus minor interaction with mantle wedge peridotite (PERID). Increasing involvement of PERID during slab melt-fluxed mantle melting explains fairly well the geochemical variations of the shoshonites, mildly alkalic to sub-alkalic basalts, and HMAs. We propose that the generation of various magma types in the late Cenozoic SW Japan arc originated simply by "slab melt-fluxed mantle melting" with large variations in melting conditions including depth, temperature, degree of melting, and flux fractions. Such volcanism has been continuous from 13 Ma (Setouchi HMA) to the present, so that the hot subduction system, involving subduction of the Shikoku Basin spreading ridge, should be continuous since 13 Ma beneath the SW Japan arc. Our results further suggest that this atypically hot system generated diverse primary arc magmas from various degrees of flux melting even though the slab source components and sub-arc mantle are fairly homogeneous.

  10. A chilled margin of komatiite and Mg-rich basaltic andesite in the western Bushveld Complex, South Africa

    Science.gov (United States)

    Maier, W. D.; Barnes, S.-J.; Karykowski, B. T.

    2016-06-01

    A chill sequence at the base of the Lower Zone of the western Bushveld Complex at Union Section, South Africa, contains aphanitic Mg-rich basaltic andesite and spinifex-textured komatiite. The basaltic andesite has an average composition of 15.2 % MgO, 52.8 % SiO2, 1205 ppm Cr, and 361 ppm Ni, whereas the komatiite has 18.7 % MgO, 1515 ppm Cr, and 410 ppm Ni. Both rock types have very low concentrations of immobile incompatible elements (0.14-0.72 ppm Nb, 7-31 ppm Zr, 0.34-0.69 ppm Th, 0.23-0.27 wt% TiO2), but high PGE contents (19-23 ppb Pt, 15-16 ppb Pd) and Pt/Pd ratios (Pt/Pd 1.4). Strontium and S isotopes show enriched signatures relative to most other Lower Zone rocks. The rocks could represent a ~20 % partial melt of subcontinental lithospheric mantle. This would match the PGE content of the rocks. However, this model is inconsistent with the high SiO2, Fe, and Na2O contents and, in particular, the low K2O, Zr, Hf, Nb, Ta, Th, LREE, Rb, and Ba contents of the rocks. Alternatively, the chills could represent a komatiitic magma derived from the asthenosphere that underwent assimilation of the quartzitic floor accompanied by crystallization of olivine and chromite. This model is consistent with the lithophile elements and the elevated Sr and S isotopic signatures of the rocks. However, in order to account for the high Pt and Pd contents of the magma, the mantle must have been twice as rich in PGE as the current estimate for PUM, possibly due to a component of incompletely equilibrated late veneer.

  11. Biomechanics and energetics of running on uneven terrain.

    Science.gov (United States)

    Voloshina, Alexandra S; Ferris, Daniel P

    2015-03-01

    In the natural world, legged animals regularly run across uneven terrain with remarkable ease. To gain understanding of how running on uneven terrain affects the biomechanics and energetics of locomotion, we studied human subjects (N=12) running at 2.3 m s(-1) on an uneven terrain treadmill, with up to a 2.5 cm height variation. We hypothesized that running on uneven terrain would show increased energy expenditure, step parameter variability and leg stiffness compared with running on smooth terrain. Subject energy expenditure increased by 5% (0.68 W kg(-1); Prunning on uneven terrain compared with smooth terrain. Step width and length variability also increased by 27% and 26%, respectively (Prunning on uneven terrain compared with smooth terrain. Calculations of gravitational potential energy fluctuations suggest that about half of the energetic increases can be explained by additional positive and negative mechanical work for up and down steps on the uneven surface. This is consistent between walking and running, as the absolute increases in energetic cost for walking and running on uneven terrain were similar: 0.68 and 0.48 W kg(-1), respectively. These results provide insight into how surface smoothness can affect locomotion biomechanics and energetics in the real world.

  12. Digital terrain data base - new possibilities of 3D terrain modeling

    Directory of Open Access Journals (Sweden)

    Mateja Rihtaršič

    1992-12-01

    Full Text Available GISs has brought new dimensions in the field of digital terrain modelling, too. Modem DTMs must be real (relational databases with high degree of "intelligence". This paper presents some of the demands, ivhich have to be solved in modern digital terrain databases, together with main steps of their's generation. Problems, connected to regional level, multi-pur pose use, new possibilities and direct integration into GIS are presented. The practical model was created across smaller test area, so few lines with practical experiences can be droped, too.

  13. Morphological modeling of terrains and volume data

    CERN Document Server

    Comic, Lidija; Magillo, Paola; Iuricich, Federico

    2014-01-01

    This book describes the mathematical background behind discrete approaches to morphological analysis of scalar fields, with a focus on Morse theory and on the discrete theories due to Banchoff and Forman. The algorithms and data structures presented are used for terrain modeling and analysis, molecular shape analysis, and for analysis or visualization of sensor and simulation 3D data sets. It covers a variety of application domains including geography, geology, environmental sciences, medicine and biology. The authors classify the different approaches to morphological analysis which are all ba

  14. Revolutionary High Mobility Rovers for Rugged Terrain

    Science.gov (United States)

    Clark, P. E.; Curtis, S. A.; Rilee, M. L.; Cheung, C. Y.; Wesenberg, R. P.; Dorband, J. E.; Lunsford, A. W.

    2006-05-01

    Reconfigurable architecture is essential in exploration because reaching features of the great potential interest, whether searching for life in volcanic terrain or water in at the bottom of craters, will require crossing a wide range of terrains. Such areas of interest are largely inaccessible to permanently appendaged vehicles. For example, morphology and geochemistry of interior basins, walls, and ejecta blankets of volcanic or impact structures must all be studied to understand the nature of a geological event. One surface might be relatively flat and navigable, while another could be rough, variably sloping, broken, or dominated by unconsolidated debris. To be totally functional, structures must form pseudo-appendages varying in size, rate, and manner of deployment (gait). We have already prototyped a simple robotic walker from a single reconfigurable tetrahedron (with struts as sides and nodes as apices) capable of tumbling and are simulating and building a prototype of the more evolved 12Tetrahedral Walker (Autonomous Moon or Mars Investigator) which has interior nodes for payload, more continuous motion, and is commandable through a user friendly interface. We are currently developing a more differentiated architecture to form detachable, reconfigurable, reshapable linearly extendable bodies to act as manual assistant subsystems on rovers, with extensions terminating in a wider range of sensors. We are now simulating gaits for and will be building a prototype rover arm. Ultimately, complex continuous n-tetrahedral structures will have deployable outer skin, and even higher degrees of freedom. Tetrahedral rover advantages over traditional wheeled or tread robots are being demonstrated and include abilities to: 1) traverse terrain more rugged in terms of slope, roughness, and obstacle size; 2) precisely place and lower instruments into hard-to-reach crevices; 3) sample more locations per unit time; 4) conform to virtually any terrain; 5) avoid falling down or

  15. Quantification of rock slope terrain properties

    Science.gov (United States)

    Volkwein, Axel; Gerber, Werner

    2017-04-01

    Rockfall trajectory simulation codes need information on the terrain properties to formulate appropriate rebound models. Usually, the manuals of rockfall simulation codes give sketches or photographs of terrain samples [1,2]. Based on these the user can select suitable terrains for the simulation area. We now would like to start a discussion whether it is possible to numerically quantify the terrain properties which would make the ground assignment more objective. Different ground properties play a role for the interaction between a falling rock and the ground: • Elastic deformation • plastic deformation • Energy absorption • friction • hardness • roughness • surface vs. underground • etc. The question is now whether it is possible to quantify above parameters and to finally provide tables that contain appropriate simulation parameters. In a first attempt we suggest different methods or parameters that might be evaluated in situ: • Small scale drop tests • Light weight deflectometer (LWD) • Particle sizes • Sliding angle • Particle distribution • Soil cover • Water content Of course, above measurements will never perfectly fit to different mountain slopes. However, if a number of measurements has been made their spreading will give an idea on the natural variability of the ground properties. As an example, the following table gives an idea on how the ME and Evd values vary for different soils. Table 1: LWD measurements on different soil types [3] Ground type Soil layer Soil humidityEvd (median)σ (median)Evd (average) Humus-carb. < 10cm dry 17.4 6.8 15.6 Regosol 10 - 30cm dry 8.6 3.9 9.4 Brownish 30 - 50cm dry 12.1 3.2 11.7 Calcaric 30 - 50cm dry 7.5 3.3 7.0 Acid brownish70 - 100cmdry 7.8 2.1 7.7 Fahlgley 10 - 30cm dry 9.2 4.0 7.7 References [1] Bartelt P et al (2016) RAMMS::rockfall user manual v1.6. SLF, Davos. [2] Dorren L.K.A., 2015. Rockyfor3D (v5.2) revealed - Transparent description of the complete 3D rockfall model. ecoris

  16. Modeling Terrain Impact on Mobile Ad Hoc Networks (MANET) Connectivity

    Science.gov (United States)

    2014-05-01

    Modeling Terrain Impact on Mobile Ad Hoc Networks ( MANET ) Connectivity Lance Joneckis Corinne Kramer David Sparrow David Tate I N S T I T U T E F...SUBTITLE Modeling Terrain Impact on Mobile Ad Hoc Networks ( MANET ) Connectivity 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...1882 ljonecki@ida.org Abstract—Terrain affects connectivity in mobile ad hoc net- works ( MANET ). Both average pairwise link closure and the rate

  17. Numerical modeling of 3-D terrain effect on MT field

    Institute of Scientific and Technical Information of China (English)

    徐世浙; 阮百尧; 周辉; 陈乐寿; 徐师文

    1997-01-01

    Using the boundary element method, the numerical modeling problem of three-dimensional terrain effect on magnetotelluric (MT) field is solved. This modeling technique can be run on PC in the case of adopting special net division. The result of modeling test for 2-D terrain by this modeling technique is basically coincident with that by 2-D modeling technique, but there is a great difference between the results of 3-D and 2-D modeling for 3-D terrain.

  18. Mathematical Modeling Of The Terrain Around A Robot

    Science.gov (United States)

    Slack, Marc G.

    1992-01-01

    In conceptual system for modeling of terrain around autonomous mobile robot, representation of terrain used for control separated from representation provided by sensors. Concept takes motion-planning system out from under constraints imposed by discrete spatial intervals of square terrain grid(s). Separation allows sensing and motion-controlling systems to operate asynchronously; facilitating integration of new map and sensor data into planning of motions.

  19. Gravity Terrain Effect of the Seafloor Topography in Taiwan

    Directory of Open Access Journals (Sweden)

    Lun-Tao Tong Tai-Rong Guo

    2007-01-01

    Full Text Available Gravity terrain correction is used to compensate for the gravitational effects of the topography residual to the Bouguer plate. The seafloor topography off the eastern offshore of Taiwan is extremely rugged, and the depth of the sea bottom could be greater than 5000 m. In order to evaluate the terrain effect caused by the seafloor topography, a modern computer algorithm is used to calculate the terrain correction based on the digital elevation model (DEM.

  20. UNIFIED REPRESENTATION FOR COLLABORATIVE VISUALIZATION OF PLANETARY TERRAIN DATA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to apply to planetary terrain mapping an alternative, multiresolution method, subdivision surfaces (subdivs), in place of conventional digital elevation...

  1. T-transformation: traversability analysis for navigation on rugged terrain

    Science.gov (United States)

    Ye, Cang; Borenstein, Johann

    2004-09-01

    In order to maneuver autonomously on rough terrain, a mobile robot must constantly decide whether to traverse or circumnavigate terrain features ahead. This ability is called Obstacle Negotiation (ON). A critical aspect of ON is the so-called traversability analysis, which evaluates the level of difficulty associated with the traversal of the terrain. This paper presents a new method for traversability analysis, called T-transformation. It is implemented in a local terrain map as follows: (1) For each cell in the local terrain map, a square terrain patch is defined that symmetrically overlays the cell; (2) a plane is fitted to the data points in the terrain patch using a least-square approach and the slope of the least-squares plane and the residual of the fit are computed and used to calculate the Traversability Index (TI) for that cell; (3) after each cell is assigned a TI value, the local terrain map is transformed into a traversability map. The traversability map is further transformed into a traversability field histogram where each element represents the overall level of difficulty to move along the corresponding direction. Based on the traversability field histogram our reactive ON system then computes the steering and velocity commands to move the robot toward the intended goal while avoiding areas of poor traversability. The traversability analysis algorithm and the overall ON system were verified by extensive simulation. We verified our method partially through experiments on a Segway Robotics Mobility Platform (RMP), albeit only on flat terrain.

  2. LUNAR TERRAIN AND ALBEDO RECONSTRUCTION FROM APOLLO IMAGERY

    Data.gov (United States)

    National Aeronautics and Space Administration — LUNAR TERRAIN AND ALBEDO RECONSTRUCTION FROM APOLLO IMAGERY ARA V NEFIAN*, TAEMIN KIM, MICHAEL BROXTON, AND ZACH MORATTO Abstract. Generating accurate three...

  3. Tool for Viewing Faults Under Terrain

    Science.gov (United States)

    Siegel, Herbert, L.; Li, P. Peggy

    2005-01-01

    Multi Surface Light Table (MSLT) is an interactive software tool that was developed in support of the QuakeSim project, which has created an earthquake- fault database and a set of earthquake- simulation software tools. MSLT visualizes the three-dimensional geometries of faults embedded below the terrain and animates time-varying simulations of stress and slip. The fault segments, represented as rectangular surfaces at dip angles, are organized into collections, that is, faults. An interface built into MSLT queries and retrieves fault definitions from the QuakeSim fault database. MSLT also reads time-varying output from one of the QuakeSim simulation tools, called "Virtual California." Stress intensity is represented by variations in color. Slips are represented by directional indicators on the fault segments. The magnitudes of the slips are represented by the duration of the directional indicators in time. The interactive controls in MSLT provide a virtual track-ball, pan and zoom, translucency adjustment, simulation playback, and simulation movie capture. In addition, geographical information on the fault segments and faults is displayed on text windows. Because of the extensive viewing controls, faults can be seen in relation to one another, and to the terrain. These relations can be realized in simulations. Correlated slips in parallel faults are visible in the playback of Virtual California simulations.

  4. Parallel path planning in unknown terrains

    Science.gov (United States)

    Prassler, Erwin A.; Milios, Evangelos E.

    1991-03-01

    We present a parallel processing approach to path planning in unknown terrains which combines map-based and sensor-based techniques into a real-time capable navigation system. The method is based on massively parallel computations in a grid of simple processing elements denoted as cells. In the course of a relaxation process a potential distribution is created in the grid which exhibits a monotonous slope from a start cell to the cell corresponding to the robot''s goal position. A shortest path is determined by means of a gradient descent criterion which settles on the steepest descent in the potential distribution. Like high-level path planning algorithms our approach is capable of planning shortest paths through an arbitrarily cluttered large-scale terrain on the basis of its current internal map. Sequentially implemented its complexity is in the order of efficient classical path planning algorithms. Unlike these algorithms however the method is also highly responsive to new obstacles encountered in the terrain. By continuing the planning process during the robot''s locomotion information about previously unknown obstacles immediately affects further path planning without a need to interrupt the ongoing planning process. New obstacles cause distortions of the potential distribution which let the robot find proper detours. By ensuring a monotonous slope in the overall distribution we avoid local minimum effects which may trap a robot in the proximity of an obstacle configuration before it has reached its goal. 1 Until the recent past research on path planning in the presence of obstacles can be assigned to two major categories: map-based high-level planning approaches and sensor-based low-level conLrol approaches. In work such as 12 path planning is treated as a high-level planning task. Assuming that an (accnrae) precompiled map of the terrain is available high-level path planners provide paths which guarantee a collision-free locomotion through an arbitrary

  5. Origin of Miocene andesite and dacite in the Goldfield-Superstition volcanic province, central Arizona: Hybrids of mafic and silicic magma mixing

    Science.gov (United States)

    Fodor, R. V.; Johnson, Kelly G.

    2016-07-01

    The Miocene Goldfield-Superstition volcanic province (G-SVP), ∼8000 km2 in central Arizona, is composed largely of silicic pyroclastic rocks and lavas, and smaller volumes of alkalic basalt and intermediate-composition lavas. Volcanism began ∼20.5 Ma as sparse rhyolitic and mainly basaltic lavas followed by intermediate lavas, lasting until ∼19 Ma. At that time, ∼1 m.y. of silicic eruptions began, creating most of the G-SVP. Petrologic studies are available for basalts and some for silicic rocks, but petrologic/geochemical information is sparse for intermediate-composition lavas. These latter, andesites and dacites, are the focus of this study, in which we present the processes and sources responsible for their origins. Goldfield-Superstition andesites and dacites have SiO2 ∼56-70 wt.% and Na2O + K2O that qualifies some as trachy-andesite and -dacite. A prominent petrographic feature is plagioclase-phyric texture (∼11-30 vol% plagioclase), where oligoclase-andesine phenocrysts have cores surrounded by corroded, or reacted, zones, mantled by higher An% plagioclase. Where corroded zones are absent, margins are etched, curved, or embayed. Groundmass plagioclase is labradorite, also more calcic than the phenocrysts. Other minerals are quartz (subrounded; embayed), clinopyroxene, amphibole, biotite, and rare titanite and zircon. A salient compositional characteristic that provides insight to andesite-dacite origins with respect to other G-SVP rocks is revealed when using SiO2 as an index. Namely, abundances of many incompatible elements, mainly HFSE and REE, decrease over the low to high SiO2 range (i.e., abundances are lower in dacites than in co-eruptive andesites and underlying alkalic basalts). As examples: G-SVP basalts have ∼50-70 ppm La, and andesites-dacites have ∼59-22 ppm La; for Zr, basalts have ∼225-170 ppm, but most andesites-dacites have ∼180-50; for Y, basalts >20 ppm, andesites-dacites ∼18-9 ppm. To understand these trends of lower

  6. Geochemical constraints on the origin of Late Mesozoic andesites from the Ningwu basin in the Middle-Lower Yangtze Valley, South China

    Science.gov (United States)

    Chen, Long; Zheng, Yong-Fei; Zhao, Zi-Fu

    2016-06-01

    An integrated study of zircon U-Pb ages, Hf-O isotopes, whole-rock major-trace elements and Sr-Nd-Hf isotopes was carried out for Mesozoic andesites from the Ningwu basin in the Middle-Lower Yangtze Valley, South China. The results not only provide insights into the origin of anorogenic magmatism in the Middle-Lower Yangtze Valley but also shed light on the petrogenesis of continental arc andesites in general. The Ningwu andesites are mainly composed of trachyandesite and trachyte, with subordinate of basaltic trachy-andesites. They exhibit variable and low MgO contents of 0.1-3.7 wt.% and low Mg# values of 1.6-51.2, high K2O contents of 2.0-9.9 wt.%. They are characterized by arc-like trace element distribution patterns, with significant enrichment in LILE and LREE but depletion in HFSE. Furthermore, these rocks exhibit relatively enriched whole-rock Sr-Nd-Hf-Pb isotope compositions, with initial 87Sr/86Sr ratios of 0.7050-0.7082, negative εNd(t) values of - 8.1 to - 1.8, and negative εHf(t) values of - 6.7 to 0.4. Zircon U-Pb dating yields consistent ages of 128 ± 2 to 133 ± 2 Ma for magma emplacement through volcanic eruption. The zircon exhibits slightly high δ18O values of 5.7-7.8‰ and variable εHf(t) values of - 5.8 to 0.7. All andesites can be categorized into two groups in view of their distinct geochemical compositions, an integrated interpretation of which allows deciphering of their petrogenesis. Group I andesite was produced by a relatively larger extent of partial melting of a more fertile and enriched mantle source that contains a greater amount of phlogopite, whereas Group II andesite was generated by a relatively smaller extent of partial melting of a less fertile and enriched mantle source that contains a less amount of phlogopite. In either case, these two mantle sources are less ultramafic in lithochemistry than normal mantle peridotite due to its reaction with metasediment-derived hydrous felsic melts. This metasomatism would take place

  7. Origin of Permian andesites from Xi Ujimqin, the Hinggan Mountains: Contributions of lower crust North China Carton

    Science.gov (United States)

    Gao, X.

    2014-12-01

    Andesite magmas at convergent margins are enriched in silica compared to magmas erupting at mid-ocean ridges and intra-plate volcanoes. Determining the cause (s) of silica enrichment is fundamental for models of continental crust formation, arc growth rates and across-arc mass balances (Plank and Langmuir, 1993; Rudnick, 1995; White et al., 2006).The Xi-Ujimqin is located the eastern segment of the Central Asian Orogenic Belt , the CAOB is composed of mainly subduction-accretion complexes, intruded by vast plutons of mainly magmatic arc origin and covered in places by their volcanic derivatives (Sengor et al. 1993; Sengor and Natalin 1996). As the most important site for Phanerozoic crustal growth in the world, the subduction-accretion complexes added ~ 5.3 million km2of material to Asia, half of which may be of juvenile origin (Sengor et al. 1993).The andesitic lavas of Daotenuoer Fms. at Xi-Ujimqin have different trace and Sr-Nd-Pb isotopic characteristic from them, these rocks span a SiO2 range of 56.83 ~ 59.17% and MgO of range of 1.21~2.91%, characterized by obviously LREE/HREE fractionation (Ce/YbCN = 11.6 ~ 16.8), strong LILE enrichment and variable Nb-Ta and Sr depletion. They have more radiogenic Sr and less radiogenic Nd and Pb isotopic composition (87Sr/86Sr(i) = 0.7063 ~ 0.7066, eNd(t) = -10.5 ~ -6.3,TDM = 1.22 ~ 1.51Ga, 206Pb / 204Pb(i) = 17.29 ~ 17.33, D7/4 = 3.7 ~ 6.9, D 8/4 = 94 ~ 104) than the contemporaneous intermediate-felsic volcanic lavas. Zircon U-Pb dating results give an emplacement age of ~253 Ma for the these rocks by LA-ICP-MS, corresponding to the Late Permian. The features of major, trace and Sr-Nd-Pb isotope of These rocks imply its sources are of attributes of lower crust North China Carton (NCC) during Paleozoic subduction and collision related to the closure of the Chinese segment of the Paleo-Asian Ocean between the NCC and south Mongolia Block (Sengor et al., 1993).

  8. The partitioning of sulfur and chlorine between andesite melts and magmatic volatiles and the exchange coefficients of major cations

    Science.gov (United States)

    Zajacz, Zoltán; Candela, Philip A.; Piccoli, Philip M.; Sanchez-Valle, Carmen

    2012-07-01

    Andesite melts were equilibrated with an H-O-S-bearing volatile phase to determine the partition coefficients for S and Cl as a function of melt composition and oxygen fugacity. The experiments were conducted in rapid-quench MHC vessel assemblies at 200 MPa and 1000 °C, and over a range of imposed fO2 between NNO-1.2 and NNO+1.8. High fluid/melt mass ratios (∼15) were employed, allowing precise and accurate partition coefficients to be obtained by mass balance calculations. Chlorine exhibits Henrian behavior at ClO-0.5 activities typical for arc magmas, with D Cl volatile/melt = 1.36 ± 0.06 (1σ) below 0.2 wt.% Cl in the melt; at higher ClO-0.5 activities, D Cl volatile/melt increases linearly to 2.11 ± 0.02 at 1 wt.% Cl in the melt. In the volatile phase: FeCl2 ∼ NaCl > KCl ∼ HCl. The determination of cation exchange coefficients for major cations yielded: K K,Na volatile/melt = 1.23 ± 0.10 (1σ) and ∗K Fe,Na volatile/melt = D Fe volatile/melt / D Na volatile/melt = 1.08 ± 0.16 (1σ). Under these conditions, the concentration of HCl in the vapor is negatively correlated with the (Na + K)/(Al + Fe3+) ratio in the melt. Reduced sulfur (S2-) appears to obey Henry's law in andesite melt-volatile system at fH2S below pyrrhotite saturation. The partition coefficient for S at fO2 = NNO-0.5 correlates negatively with the FeO concentration in the melt, changing from 254 ± 25 at 4.0 wt.% FeO to 88 ± 6 at 7.5 wt.% FeO. Pyrrhotite saturation is reached when approximately 3.2 mol% S is present in the volatile phase at fO2 = NNO-0.5. At the sulfide/sulfate transition, the partition coefficient of S drops from 171 ± 23 to 21 ± 1 at a constant FeO content of ∼6 wt.% in the melt. At fO2 = NNO+1.8, anhydrite saturation is reached at ∼3.3 mol% S present in the volatile phase. Aqueous volatiles exsolving from intermediate to mafic magmas can efficiently extract S, and effect its transfer to sites of magmatic-hydrothermal ore deposit formation.

  9. Single-Frame Terrain Mapping Software for Robotic Vehicles

    Science.gov (United States)

    Rankin, Arturo L.

    2011-01-01

    This software is a component in an unmanned ground vehicle (UGV) perception system that builds compact, single-frame terrain maps for distribution to other systems, such as a world model or an operator control unit, over a local area network (LAN). Each cell in the map encodes an elevation value, terrain classification, object classification, terrain traversability, terrain roughness, and a confidence value into four bytes of memory. The input to this software component is a range image (from a lidar or stereo vision system), and optionally a terrain classification image and an object classification image, both registered to the range image. The single-frame terrain map generates estimates of the support surface elevation, ground cover elevation, and minimum canopy elevation; generates terrain traversability cost; detects low overhangs and high-density obstacles; and can perform geometry-based terrain classification (ground, ground cover, unknown). A new origin is automatically selected for each single-frame terrain map in global coordinates such that it coincides with the corner of a world map cell. That way, single-frame terrain maps correctly line up with the world map, facilitating the merging of map data into the world map. Instead of using 32 bits to store the floating-point elevation for a map cell, the vehicle elevation is assigned to the map origin elevation and reports the change in elevation (from the origin elevation) in terms of the number of discrete steps. The single-frame terrain map elevation resolution is 2 cm. At that resolution, terrain elevation from 20.5 to 20.5 m (with respect to the vehicle's elevation) is encoded into 11 bits. For each four-byte map cell, bits are assigned to encode elevation, terrain roughness, terrain classification, object classification, terrain traversability cost, and a confidence value. The vehicle s current position and orientation, the map origin, and the map cell resolution are all included in a header for each

  10. Genesis of high-Mg andesites (HMA) through shallow fractionation of primitive arc basalts at elevated oxygen fugacities (and low initial water contents)

    Science.gov (United States)

    Zellmer, Georg; Shellnutt, Gregory

    2010-05-01

    The petrogenesis of high-Mg andesites has been linked to a variety of processes, including partial melting of hydrous mantle peridotite, re-equilibration of partial melts of the subducting slab with the mantle wedge, and assimilation of lower crustal cumulates into dacitic melts. Yet none of these processes can explain the recently identified association of adakitic andesites, many of which are high-Mg andesites, with regions of elevated surface heat flux that are related to unusually shallow magma ponding levels in the upper crust (Zellmer, 2009). Using MELTS modeling, we demonstrate here that at elevated oxygen fugacities (NNO+2, which based on whole-rock Fe3+/Fe2+ ratios is appropriate for the Western and Central Aleutians, the Trans-Mexican Volcanic Belt, and the Setouchi Volcanic Belt), shallow crustal pressures (0.7 kbar), and initial H2O contents between 0.5 and 4 wt%, iron-magnesium spinel will be fractionated from primitive arc basalts, producing andesitic residual melts with elevated Mg#. Subsequent assimilation of a few percent of autocrystic mafic phases makes typical high-Mg andesites with forsteritic olivines. Orthopyroxenes in equilibrium with these melts are Cr-rich due to increased uptake of Cr into orthopyroxene (Dopx-lq ≥25) at lower temperatures (≤1130° C) and elevated oxygen fugacities (NNO+2). While arc magmas with high initial H2O contents will undergo early degassing induced crystallization and viscous stagnation, lower primary melt H2O contents will result in delayed crystallization and shallower magma ponding levels, accounting for elevated surface heat flux. Our findings are therefore consistent with the location of many high-Mg andesites in areas of high surface heat flux, and challenge the commonly accepted notion that these compositions are particularly hydrous primary melts generated in equilibrium with mantle peridotite. Reference: Zellmer G.F. (2009) Petrogenesis of Sr-rich adakitic rocks at volcanic arcs: insights from global

  11. Halogens behaviours in Magma Degassing: Insights into Eruptive Dynamics, Hydrothermal Systems and Atmospheric Impact of Andesitic Volcanism

    Science.gov (United States)

    Villemant, B.; Balcone, H.; Mouatt, J.; Michel, A.; Komorowski, J.; Boudon, G.

    2007-12-01

    Shallow degassing of H2O in andesitic magmas determines the eruptive styles of volcanic eruptions and contributes to the hydrothermal systems developed around active volcanoes. Halogens behaviour during magma degassing primarily depends on their incompatible behaviour in the melts and on water solubility. Thus, residual contents of halogens in volcanic juvenile vitric clasts may be used as tracers of H2O degassing processes during explosive and effusive eruptions. Because of the large range of water-melt partition coefficients of halogens and their relatively low diffusion coefficients, a comparison of F, Cl, Br and I contents in volcanic clasts in function of their vesicularity and micro-cristallinity allows to precisely model the main degassing processes and to establish constraints on pre-eruptive conditions. Halogens acids (HCl, HBr and HI) extracted in the vapour phase have much more complex behaviours because of their high solubility in low temperature thermal waters, their variable condensation temperatures and their very high reactivity when mixed with low temperature and oxidizing atmospheric gases. A comparison of model compositions of high temperature gases with the composition of thermal waters, and gases from fumaroles or plumes of active volcanoes allows to characterise the shallow volcanic system and its evolutionary states. Variable halogen behaviours are discussed for a variety of eruption types (plinian, vulcanian and dome-forming) and active volcanic systems from the Lesser Antilles (Montagne Pelee, Soufrière of Guadeloupe, Soufriere Hills of Montserrat).

  12. The Link between Hi - Magnesium Andesite Distribution in Baja California Peninsula and the Undetached Fragments of the Farallon Plate

    Science.gov (United States)

    Wang, Y.; Forsyth, D. W.; Savage, B.

    2009-12-01

    About 12 Ma, the Guadalupe and Magdalena microplates ceased subducting beneath the North American continent, leaving behind plate fragments that became incorporated into the Pacific plate as spreading ceased. Spreading directions changed dramatically on Magdalena spreading centers, suggesting that the Farallon slab detached from the microplate fragments before or during the cessation of spreading. Although the sinking Farallon plate must have detached from those two microplates, it is not known where the detachments occurred and how much of the young slab was left behind still attached to the unsubducted surface microplates. We delineate the undetached Farallon fragments by looking for associated seismic velocity anomalies using teleseismic Rayleigh wave tomography and the stations of the USArray, NARS-Baja and RESBAN arrays. The lateral extent of the remanent plate fragments is indicated by a high (positive) velocity anomaly at 100 km depth (Figure 1). This landward edge of this anomaly coincides with the distribution of post-subduction high-Mg andesites (Bajaites, black region in Figure 1), which are inferred to involve fluid fluxed melting in overlying asthenospheric wedge and melting of the subducted oceanic crust. Shear velocity anomaly at 100 km

  13. 14 CFR 93.311 - Minimum terrain clearance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Minimum terrain clearance. 93.311 Section 93.311 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... of Grand Canyon National Park, AZ § 93.311 Minimum terrain clearance. Except in an emergency,...

  14. Colour based off-road environment and terrain type classification

    NARCIS (Netherlands)

    Jansen, P.; Mark, W. van der; Heuvel, J.C. van den; Groen, F.C.A.

    2005-01-01

    Terrain classification is an important problem that still remains to be solved for off-road autonomous robot vehicle guidance. Often, obstacle detection systems are used which cannot distinguish between solid obstacles such as rocks or soft obstacles such as tall patches of grass. Terrain classifica

  15. Design Of An Omnidirectional Mobile Robot For Rough Terrain

    Science.gov (United States)

    2007-09-01

    rough terrain, isotropy, mobile robots , design I. INTRODUCTION Mobile robots are finding increasing use in military [1], disaster recovery [2], and...exploration applications [3]. These applications frequently require operation in rough, unstructured terrain. Currently, most mobile robots designed...perform some maneuvers, such as lateral displacement. Omnidirectional mobile robots could potentially navigate faster and more robustly through

  16. Terrain Perception in a Shape Shifting Rolling-Crawling Robot

    Directory of Open Access Journals (Sweden)

    Fuchida Masataka

    2016-09-01

    Full Text Available Terrain perception greatly enhances the performance of robots, providing them with essential information on the nature of terrain being traversed. Several living beings in nature offer interesting inspirations which adopt different gait patterns according to nature of terrain. In this paper, we present a novel terrain perception system for our bioinspired robot, Scorpio, to classify the terrain based on visual features and autonomously choose appropriate locomotion mode. Our Scorpio robot is capable of crawling and rolling locomotion modes, mimicking Cebrenus Rechenburgi, a member of the huntsman spider family. Our terrain perception system uses Speeded Up Robust Feature (SURF description method along with color information. Feature extraction is followed by Bag of Word method (BoW and Support Vector Machine (SVM for terrain classification. Experiments were conducted with our Scorpio robot to establish the efficacy and validity of the proposed approach. In our experiments, we achieved a recognition accuracy of over 90% across four terrain types namely grass, gravel, wooden deck, and concrete.

  17. 75 FR 5767 - All Terrain Vehicle Chinese Language Webinar; Meeting

    Science.gov (United States)

    2010-02-04

    ... COMMISSION All Terrain Vehicle Chinese Language Webinar; Meeting AGENCY: Consumer Product Safety Commission... Terrain Vehicle Chinese Language Webinar. The webinar will focus on CPSC's requirements for ATV's... February 4, 2010 at 6:00 am Eastern Standard Time. Location: The meeting will be held live via...

  18. Stereo based Obstacle Detection with Uncertainty in Rough Terrain

    NARCIS (Netherlands)

    Mark, W. van der; Heuvel, J.C. van den; Groen, F.C.A.

    2007-01-01

    Autonomous robot vehicles that operate in offroad terrain should avoid obstacle hazards. In this paper we present a stereo vision based method that is able to cluster reconstructed terrain points into obstacles by evaluating their relative angles and distances. In our approach, constraints are enfor

  19. 47 CFR 80.759 - Average terrain elevation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Average terrain elevation. 80.759 Section 80... Average terrain elevation. (a)(1) Draw radials from the antenna site for each 45 degrees of azimuth.... (d) Average the values by adding them and dividing by the number of readings along each radial....

  20. Statistical Modeling of Robotic Random Walks on Different Terrain

    Science.gov (United States)

    Naylor, Austin; Kinnaman, Laura

    Issues of public safety, especially with crowd dynamics and pedestrian movement, have been modeled by physicists using methods from statistical mechanics over the last few years. Complex decision making of humans moving on different terrains can be modeled using random walks (RW) and correlated random walks (CRW). The effect of different terrains, such as a constant increasing slope, on RW and CRW was explored. LEGO robots were programmed to make RW and CRW with uniform step sizes. Level ground tests demonstrated that the robots had the expected step size distribution and correlation angles (for CRW). The mean square displacement was calculated for each RW and CRW on different terrains and matched expected trends. The step size distribution was determined to change based on the terrain; theoretical predictions for the step size distribution were made for various simple terrains. It's Dr. Laura Kinnaman, not sure where to put the Prefix.

  1. Terrain Identification for Prosthetic Knees Based on Electromyographic Signal Features

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The features of electromyographic (EMG) signals were investigated while people walking on different terrains, including up and down slopes, up and down stairs, and during level walking at different speeds. The features were used to develop a terrain identification method. The technology can be used to develop an intelligent transfemoral prosthetic limb with terrain identification capability. The EMG signals from 8 hip muscles of 13 healthy persons were recorded as they walked on the different terrains. The signals from the sound side of a transfemoral amputee were also recorded. The features of these signals were obtained using data processing techniques with an identification process developed for the identification of the terrain type. The procedure was simplified by using only the signals from three muscles. The identification process worked well in an intelligent prosthetic knee in a laboratory setting.

  2. Learning Long-range Terrain Perception for Autonomous Mobile Robots

    Directory of Open Access Journals (Sweden)

    Mingjun Wang

    2010-02-01

    Full Text Available Long-range terrain perception has a high value in performing efficient autonomous navigation and risky intervention tasks for field robots, such as earlier recognition of hazards, better path planning, and higher speeds. However, Stereo-based navigation systems can only perceive near-field terrain due to the nearsightedness of stereo vision. Many near-to-far learning methods, based on regions' appearance features, are proposed to predict the far-field terrain. We proposed a statistical prediction framework to enhance long-range terrain perception for autonomous mobile robots. The main difference between our solution and other existing methods is that our framework not only includes appearance features as its prediction basis, but also incorporates spatial relationships between terrain regions in a principled way. The experiment results show that our framework outperforms other existing approaches in terms of accuracy, robustness and adaptability to dynamic unstructured outdoor environments.

  3. Conically scanning lidar error in complex terrain

    Directory of Open Access Journals (Sweden)

    Ferhat Bingöl

    2009-05-01

    Full Text Available Conically scanning lidars assume the flow to be homogeneous in order to deduce the horizontal wind speed. However, in mountainous or complex terrain this assumption is not valid implying a risk that the lidar will derive an erroneous wind speed. The magnitude of this error is measured by collocating a meteorological mast and a lidar at two Greek sites, one hilly and one mountainous. The maximum error for the sites investigated is of the order of 10 %. In order to predict the error for various wind directions the flows at both sites are simulated with the linearized flow model, WAsP Engineering 2.0. The measurement data are compared with the model predictions with good results for the hilly site, but with less success at the mountainous site. This is a deficiency of the flow model, but the methods presented in this paper can be used with any flow model.

  4. Enveloping Relief Surfaces of Landslide Terrain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Two relief surfaces that envelop the rock fall region in a part of Garhwal Himalayas around Chamoli have been identified. Relative relief and absolute relief have been analyzed and the enveloping surfaces recorded at two levels of relief in the landscape. All landslide activity lies within these surfaces. The lower enveloping surface (800 m) dips due south by 7-8 degrees, due to an elevation rise of 100 meters within 12 km from south to north, i.e., a gradient of 8 percent. The nature of the surface is smooth. The upper enveloping surface (> 2500 m) is almost parallel to the lower one but its surface is undulatory due to landslides and denudation. The area has been a seismically active region and has undergone seismic activity up until recently, as evidenced by the Chamoli earthquake of 29th March 1999. The effects of earthquakes are seen at higher levels in the form of landslide imprints on the terrain.

  5. Maintaining Contour Trees of Dynamic Terrains

    DEFF Research Database (Denmark)

    Agarwal, Pankaj K.; Mølhave, Thomas; Revsbæk, Morten

    2015-01-01

    We study the problem of maintaining the contour tree T of a terrain Sigma, represented as a triangulated xy-monotone surface, as the heights of its vertices vary continuously with time. We characterize the combinatorial changes in T and how they relate to topological changes in Sigma. We present...... a kinetic data structure (KDS) for maintaining T efficiently. It maintains certificates that fail, i.e., an event occurs, only when the heights of two adjacent vertices become equal or two saddle vertices appear on the same contour. Assuming that the heights of two vertices of Sigma become equal only O(1......) times and these instances can be computed in O(1) time, the KDS processes O(kappa + n) events, where n is the number of vertices in Sigma and kappa is the number of events at which the combinatorial structure of T changes, and processes each event in O(log n) time. The KDS can be extended to maintain...

  6. Digital terrain modeling with the Chebyshev polynomials

    CERN Document Server

    Florinsky, I V

    2015-01-01

    Mathematical problems of digital terrain analysis include interpolation of digital elevation models (DEMs), DEM generalization and denoising, and computation of morphometric variables by calculation of partial derivatives of elevation. Traditionally, these procedures are based on numerical treatments of two-variable discrete functions of elevation. We developed a spectral analytical method and algorithm based on high-order orthogonal expansions using the Chebyshev polynomials of the first kind with the subsequent Fejer summation. The method and algorithm are intended for DEM analytical treatment, such as, DEM global approximation, denoising, and generalization as well as computation of morphometric variables by analytical calculation of partial derivatives. To test the method and algorithm, we used a DEM of the Northern Andes including 230,880 points (the elevation matrix 480 $\\times$ 481). DEMs were reconstructed with 480, 240, 120, 60, and 30 expansion coefficients. The first and second partial derivatives ...

  7. Groundwater flood hazards in lowland karst terrains

    Science.gov (United States)

    Naughton, Owen; McCormack, Ted

    2016-04-01

    The spatial and temporal complexity of flooding in karst terrains pose unique flood risk management challenges. Lowland karst landscapes can be particularly susceptible to groundwater flooding due to a combination of limited drainage capacity, shallow depth to groundwater and a high level of groundwater-surface water interactions. Historically the worst groundwater flooding to have occurred in the Rep. of Ireland has been centred on the Gort Lowlands, a karst catchment on the western coast of Ireland. Numerous notable flood events have been recorded throughout the 20th century, but flooding during the winters of 2009 and 2015 were the most severe on record, inundating an area in excess of 20km2 and causing widespread and prolonged disruption and damage to property and infrastructure. Effective flood risk management requires an understanding of the recharge, storage and transport mechanisms during flood conditions, but is often hampered by a lack of adequate data. Using information gathered from the 2009 and 2015 events, the main hydrological and geomorphological factors which influence flooding in this complex lowland karst groundwater system under are elucidated. Observed flood mechanisms included backwater flooding of sinks, overland flow caused by the overtopping of sink depressions, high water levels in turlough basins, and surface ponding in local epikarst watersheds. While targeted small-scale flood measures can locally reduce the flood risk associated with some mechanisms, they also have the potential to exacerbate flooding down-catchment and must be assessed in the context of overall catchment hydrology. This study addresses the need to improve our understanding of groundwater flooding in karst terrains, in order to ensure efficient flood prevention and mitigation in future and thus help achieve the aims of the EU Floods Directive.

  8. Predicting Potential Evaporation in Topographically Complex Terrain

    Science.gov (United States)

    Koohafkan, M.; Thompson, S. E.; Hamilton, M. P.

    2012-12-01

    Predicting and understanding the water cycle in topographically complex terrain poses challenges for upscaling point-scale measurements of water and energy balance and for downscaling observations made from remote sensing or predictions made via global circulation models. This study evaluates hydrologic and climate data drawn from a spatially-distributed wireless sensor network at the Blue Oak Ranch Reserve near San Jose, California to investigate the influence of topographic variation, landscape position, and local ecology (vegetation) on one core component of the water balance: potential evaporation. High-resolution observations of solar radiation, ambient temperature, wind speed, and relative humidity are combined with canopy maps generated from LiDAR flyovers to develop spatially-distributed predictions of potential evaporation. These data are compared to estimates of EP based on inverse modeling of surface soil moisture data. Preliminary results suggest that the spatial structure of microclimate at Blue Oak Ranch Reserve is dominated by variations around the elevation gradient, with strong nocturnal inversions hypothesized to reflect the influence of the coastal marine layer. Estimates of EP based on the Penman-Monteith equation suggest that EP could vary by up to a factor of 5 across the site, with differences in vapor pressure deficit and canopy height largely responsible for this variability. The results suggest that a) large differences in the timing and magnitude of water stress could arise in topographically complex terrain due to localized differences in energy balance, and b) both localized and regional effects need to be accounted for when downscaling climate data over topographically complex sites. 2) Color map showing preliminary estimates of annual EP incorporating canopy information (spatially-distributed values of aerodynamic resistance and LAI) drawn from LiDAR imagery. The effect of the resistance on the dynamics is striking in its ability to

  9. Self-Supervised Learning to Visually Detect Terrain Surfaces for Autonomous Robots Operating in Forested Terrain

    Science.gov (United States)

    2012-01-01

    classified. Stereo algorithms can generate 3D point clouds at relatively high frequency (sev- eral hertz). However, the resulting depth map is typically...10.1002/rob 280 • Journal of Field Robotics—2012 (a) (b) (c) (d) Figure 1. Experimental robot platform, (a) lateral view and (b) top view. (c) Perception ... monocular road detection in desert terrain. In Proceedings of robotics: Science and systems, Philadelphia, USA. Elmqvist, M. (2002). Ground surface

  10. Potential reactivity of the andesitic rocks from Cabo de Gata (SE Spain); Reactividad potencial de las rocas andesiticas de Cabo de Gata (SE de Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Soriano, J.; Iglesia, A. la; Garcia Calleja, M. A.; Lopez-Ruiz, J.

    2010-07-01

    Andesitic rocks produce an alkali-silica reaction with the components of the interstitial phase of concrete. This reaction can be considered as belonging to the slow-kinetic type, since the incongruent dissolution of the rock-forming minerals leads to the late formation of siliceous calc-alkaline gel. As a conquence, the conventional mortar-bar method does not detect such reaction until 90 days later. (Author) 9 refs.

  11. Shallow active-source imaging of an andesite dike in southern New Mexico: comparing Reftek Texan and Fairfield Z-Land recordings

    Science.gov (United States)

    Karplus, M. S.; Kaip, G.; Harder, S. H.; Johnson, K.

    2016-12-01

    In October 2015, the Advanced Exploration Seismology class at the University of Texas at El Paso together with additional volunteers acquired a 500-m active-source seismic profile across an andesite dike adjacent to the Rio Grande River near Sunland Park, New Mexico. Receivers included 100 RT-125 Reftek Texans with 4.5-Hz geophones, spaced every 5 m, and 47 Fairfield Z-Land nodes incorporating 5-Hz 3C geophones, spaced approximately every 10 m. A 8-gauge, 400 grain seismic gun source was fired every 5-10 m along most of the profile. Several locations at the ends of the profile experienced multiple gun shots, which have been stacked to increase signal-to-noise. We discuss similarities and differences in field methods and data acquired using the Texans compared to the nodes for a shallow active-source experiment. We extend the discussion to other types of active-source experiments using other recently-acquired nodal datasets. We observe changes in velocity between the andesite dike and surrounding lithologies, and create a seismic reflection image of the andesite dike.

  12. Mobile robots traversability awareness based on terrain visual sensory data fusion

    Science.gov (United States)

    Shirkhodaie, Amir

    2007-04-01

    In this paper, we have presented methods that significantly improve the robot awareness of its terrain traversability conditions. The terrain traversability awareness is achieved by association of terrain image appearances from different poses and fusion of extracted information from multimodality imaging and range sensor data for localization and clustering environment landmarks. Initially, we describe methods for extraction of salient features of the terrain for the purpose of landmarks registration from two or more images taken from different via points along the trajectory path of the robot. The method of image registration is applied as a means of overlaying (two or more) of the same terrain scene at different viewpoints. The registration geometrically aligns salient landmarks of two images (the reference and sensed images). A Similarity matching techniques is proposed for matching the terrain salient landmarks. Secondly, we present three terrain classifier models based on rule-based, supervised neural network, and fuzzy logic for classification of terrain condition under uncertainty and mapping the robot's terrain perception to apt traversability measures. This paper addresses the technical challenges and navigational skill requirements of mobile robots for traversability path planning in natural terrain environments similar to Mars surface terrains. We have described different methods for detection of salient terrain features based on imaging texture analysis techniques. We have also presented three competing techniques for terrain traversability assessment of mobile robots navigating in unstructured natural terrain environments. These three techniques include: a rule-based terrain classifier, a neural network-based terrain classifier, and a fuzzy-logic terrain classifier. Each proposed terrain classifier divides a region of natural terrain into finite sub-terrain regions and classifies terrain condition exclusively within each sub-terrain region based on

  13. Dialogar con Dios: el uso de las imágenes en los conventos femeninos de dominicas en la Teutonia bajomedieval

    Directory of Open Access Journals (Sweden)

    Jäggi, Carola

    2014-06-01

    Full Text Available Several convent chronicles from within the Dominican Province of Upper Germany dating back to the 14th and 15th centuries provide interesting insight into the manner in which works of art were utilized in late medieval religious life. Amongst other findings, study of the sources reveals that the nuns used images of the Mother of God and of the Crucified Christ not always and not only to meditate upon and commemorate the facts of salvation, but above all to receive support and solace in times of distress. The conception of icons derived from these sources is of the merging of archetype and image and of the indwelling of the person depicted in the image. Examples such as St Katharinental in northeastern Switzerland, where a large supply of images has been preserved in addition to numerous statues, are of particular interest for the study.Procedentes de la antigua provincia dominica alto alemana han llegado hasta nosotros algunos Schwesternbücher o Libros de monjas de los siglos XIV y XV que ofrecen interesantes indicaciones sobre el uso que se hacía en los conventos de mujeres de la Baja edad Media de las obras de arte que en ellos se custodiaban. Entre otras cosas se desprende de estas fuentes que las hermanas utilizaban las imágenes no siempre y no sólo como instrumentos de meditación para conmemorar los acontecimientos de la Historia de Salvación, sino sobre todo acudían en tiempos de necesidad a las imágenes de la Madre de Dios y del crucifijo para obtener de ellas consejo y consuelo. Parece por consiguiente que se trata de una forma de comprensión de la imagen que unía el arquetipo original y su representación, “morando” el representado en su imagen. Casos como el de St. Katharinental en el noreste de Suiza, donde además de las fuentes escritas se ha conservado un buen número de tallas del siglo XIV, son especialmente interesantes para esta cuestión.

  14. Terrain aided navigation for autonomous underwater vehicles with coarse maps

    Science.gov (United States)

    Zhou, Ling; Cheng, Xianghong; Zhu, Yixian

    2016-09-01

    Terrain aided navigation (TAN) is a form of geophysical localization technique for autonomous underwater vehicles (AUVs) operating in GPS-denied environments. TAN performance on sensor-rich AUVs has been evaluated in sea trials. However, many challenges remain before TAN can be successfully implemented on sensor-limited AUVs, especially with coarse maps. To improve TAN performance over coarse maps, a Gaussian process (GP) is proposed for the modeling of bathymetric terrain and integrated into the particle filter (GP-PF). GP is applied to provide not only the bathymetric value prediction through learning a set of bathymetric data from coarse maps but also the variance of the prediction. As a measurement update, calculated on bathymetric deviation is performed through the PF to obtain absolute and bounded positioning accuracy. Through the analysis of TAN performance on experimental data for two different terrains with map resolutions of 10-50 m, both the ability of the proposed model to represent the actual bathymetric terrain with accuracy and the effect of the GP-PF for TAN on sensor-limited systems in suited terrain are demonstrated. The experiment results further verify that there is an inverse relationship between the coarseness of the map and the overall TAN accuracy in rough terrains, but there is hardly any relationship between them in relatively flat terrains.

  15. From digital elevation model data to terrain depiction data

    Science.gov (United States)

    Helmetag, Arnd; Smietanski, Guillaume; Baumgart, Michael; Kubbat, Wolfgang

    1999-07-01

    The analysis of accidents focused our work on the avoidance of 'Controlled Flight Into Terrain' caused by insufficient situation awareness. Analysis of safety concepts led us to the design of the proposed synthetic vision system that will be described. Since most information on these 3D-Displays is shown in a graphical way, it can intuitively be seized by the pilot. One key element of SVS is terrain depiction, that is the topic of this paper. Real time terrain depiction has to face two requirements. On the one hand spatial awareness requires recognition of synthetic environment demanding characteristics. On the other hand the number of rendered polygons has to be minimized due to limitations of real time image generation performance. Visual quality can significantly be enhanced if equidistant data like Digital Elevation Model data (DEM) are vectorized. One method of data vectorization will be explained in detail and advantages will be mentioned. In Virtual Reality (VR) applications, conventional decimation software degrades the visual quality of geometry that is compensated by complex textures and lighting. Since terrain decimated with those tools looses its characteristics, and textures are not acceptable for several reasons, a terrain specific decimation has to be performed. How can a Digital Elevation Model (DEM) be decimated without decreasing the visualization value? In this paper, extraction of terrain characteristics and adapted decimation will be proposed. Steps from DEM to Terrain Depiction Data (TDD) are discussed in detail.

  16. Self-Supervised Learning of Terrain Traversability from Proprioceptive Sensors

    Science.gov (United States)

    Bajracharya, Max; Howard, Andrew B.; Matthies, Larry H.

    2009-01-01

    Robust and reliable autonomous navigation in unstructured, off-road terrain is a critical element in making unmanned ground vehicles a reality. Existing approaches tend to rely on evaluating the traversability of terrain based on fixed parameters obtained via testing in specific environments. This results in a system that handles the terrain well that it trained in, but is unable to process terrain outside its test parameters. An adaptive system does not take the place of training, but supplements it. Whereas training imprints certain environments, an adaptive system would imprint terrain elements and the interactions amongst them, and allow the vehicle to build a map of local elements using proprioceptive sensors. Such sensors can include velocity, wheel slippage, bumper hits, and accelerometers. Data obtained by the sensors can be compared to observations from ranging sensors such as cameras and LADAR (laser detection and ranging) in order to adapt to any kind of terrain. In this way, it could sample its surroundings not only to create a map of clear space, but also of what kind of space it is and its composition. By having a set of building blocks consisting of terrain features, a vehicle can adapt to terrain that it has never seen before, and thus be robust to a changing environment. New observations could be added to its library, enabling it to infer terrain types that it wasn't trained on. This would be very useful in alien environments, where many of the physical features are known, but some are not. For example, a seemingly flat, hard plain could actually be soft sand, and the vehicle would sense the sand and avoid it automatically.

  17. Late Triassic high-Mg andesite/dacite suites from northern Hohxil, North Tibet: Geochronology, geochemical characteristics, petrogenetic processes and tectonic implications

    Science.gov (United States)

    Wang, Qiang; Li, Zheng-Xiang; Chung, Sun-Lin; Wyman, Derek A.; Sun, Ya-Li; Zhao, Zhen-Hua; Zhu, Yin-Tang; Qiu, Hua-Ning

    2011-09-01

    This study reports age, petrologic and geochemical data for andesites and dacites from the Late Triassic sedimentary strata of northern Hohxil, in the Hohxil-Songpan-Ganzi Block (northern Tibet), which constitutes the most voluminous Triassic strata on Earth. LA-ICP-MS zircon U-Pb analysis of dacite (210.4 ± 1.9 Ma) and whole rock 40Ar- 39Ar analyses for both the andesites and dacites (211 ± 2 Ma and 210.9 ± 1.6 Ma) show that the rocks were almost contemporaneous. Both rock types are sodium-rich and calc-alkaline. The andesites, characterized by high MgO (up to 10 wt.%) or Mg # (~ 70), TiO 2, Al 2O 3, Cr, Ni, La/Yb and Th/La, but low Nb/Ta ratios, are geochemically similar to sanukitoids in southeastern Japan. The dacites are strongly peraluminous, and have high Al 2O 3 and La/Yb, low Y and Yb, coupled with negligible to positive Eu and Sr anomalies, comparable to slab-derived adakites in the circum Pacific arc system. Both rocks exhibit strongly fractionated platinum group element patterns, with Pt/Pt* (Pt anomaly), (Pt/Ir) N and Re/Os ratios higher than those of the primitive mantle. They have uniformly low ɛNd(t) values (- 7.57--9.59) and high ( 86Sr/ 87Sr) i ratios (0.7086-0.7106) that imply a continental rather than oceanic type magma source. We suggest that the northern Hohxil dacites were produced by partial melting of subducted sediments on the northward-subducting Songpan-Ganzi oceanic slab, and the high-Mg andesites were formed by subsequent interaction between the sediment-derived melts and mantle wedge peridotites. Taking into account the Triassic magmatic record from nearby regions, we suggest that the Late Triassic high-Mg andesite/dacite suites of northern Hohxil were generated in a forearc setting, and propose that double-sided subduction eventually closed the Songpan-Ganzi ocean during the Late Triassic.

  18. Mechanics and Timescales of Magma Mixing Inferred by Texture and Petrology of Basalt Inclusions and Host Andesite From the 2006 Eruption of Augustine Volcano, Alaska

    Science.gov (United States)

    Vitale, M. L.; Browne, B. L.

    2010-12-01

    This study characterizes the texture, mineralogy and phenocryst disequilibrium textures in basaltic inclusions and host andesite lavas and scoria to advance our understanding of the mechanics and timescales of open system magma processes driving the 2006 eruption at Augustine Volcano, Alaska. Inclusions account for approximately 1 volume percent in all andesite lithologies emplaced during the explosive, continuous, and effusive eruption phases. In outcrop, quenched basaltic to andesite inclusions (51.3 to 57.3 weight percent SiO2) hosted by andesite lavas (59.1-62.6 weight percent SiO2) range in diameter from 1 cm to over 9 cm, are dark black and characterized by vesicular interiors, quenched and cuspate margins, and porphyritic texture. Inclusion mineralogy is dominated by phenocryst-sized plagioclase with lesser amounts of hornblende, clinopyroxene and olivine, as well as, microphenocrysts-sized plagioclase, hornblende, clinopryoxene, olivine, magnetite, ilmenite and apatite in a glassy, vesicular and acicular groundmass. Intrusion of a hotter, basaltic magma into a cooler silicic magma followed by inclusion formation through mingling processes is evidenced by (1) plagioclase crystal textures displaying (a) oscillatory zoned interiors surrounded by a dusty sieved layer and enclosed by clear, euhedral overgrowth rims, (b) coarsely-sieved interiors characterized by 0.01 mm -0.02 mm diameter melt inclusions and/or similarly sized inclusions of clinopyroxene, orthopryoxene, or hornblende, (2) Anorthite concentration profiles of engulfed host plagioclase crystals displaying contact with a basaltic magma, (3)Fe-Ti oxides from inclusions and low-silica andesite host recording core to rim temperatures ranging from 908°C to 1100°C, indicative of pre- and post- mixing temperatures, respectively, with oxygen fugacity approximately 2 log units above the nickel-nickel oxide buffer. The closest approximation of the basaltic end-member magma composition involved in magma

  19. Dynamics of explosive paroxysms at open andesitic systems: high-resolution mass distribution analyses of 2006 tephra from Tungurahua volcano (Ecuador)

    Science.gov (United States)

    Le Pennec, J.; Eychenne, J.; Ramon, P.; Yepes, H.

    2012-12-01

    Many andesitic volcanoes at subduction plate margins can experience in the course of their evolution periods of sub-continuous eruption during years, decades, or centuries. Such long-lived periods may embrace more or less intense outgassing events, extrusion of viscous lava flows and domes (e.g. Colima in Mexico, Merapi in Indonesia, Arenal in Costa Rica), and explosive activity of uneven intensity (e.g. Semeru in Indonesia, Sakurajima in Japan, Sangay in Ecuador). In addition, strong explosive events of short duration may occur, with potential generation of pyroclastic flows on the flanks and beyond, which can pose significant hazards in populated regions. The origin and dynamics of such violent eruptions remain poorly known and may involve a combination of different factors. Tungurahua volcano, Ecuador, reawaken in 1999 and is an example of such open-system behaviour that experienced a strong and deadly andesitic pyroclastic flow-forming event in August 2006. Inspection of the deposits suggested that the event could have been triggered by magma mixing (silicic pumices in the tephra), magma-water interaction (presence of xenolithic clasts) or deep andesitic magma reinjection (based on mineral chemistry). Here we investigate these options by performing a high-resolution mass budget analysis of the scoria fall deposit. This is achieved by analysing componentry compositions and their mass distribution pattern in the layer, which allow us to document and integrate exponential and power laws mass decay rates over wide areas. The results yield a total mass for the tephra layer of ~2 x 1010kg. The pumice mass fraction is far too small (< 0.4 %) to account for the high explosivity of the 2006 event. Similarly, the xenoclastic mass fraction is small (0.2%) and suggests limited magma-water interaction. Instead, we interpret these xenoclasts as a result of upper conduit erosion at a rate of ~30 cm/hour during the paroxysm. Altogether our results support an explosive event

  20. MRO CTX-based Digital Terrain Models

    Science.gov (United States)

    Dumke, Alexander

    2016-04-01

    In planetary surface sciences, digital terrain models (DTM) are paramount when it comes to understanding and quantifying processes. In this contribution an approach for the derivation of digital terrain models from stereo images of the NASA Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) are described. CTX consists of a 350 mm focal length telescope and 5000 CCD sensor elements and is operated as pushbroom camera. It acquires images with ~6 m/px over a swath width of ~30 km of the Mars surface [1]. Today, several approaches for the derivation of CTX DTMs exist [e. g. 2, 3, 4]. The discussed approach here is based on established software and combines them with proprietary software as described below. The main processing task for the derivation of CTX stereo DTMs is based on six steps: (1) First, CTX images are radiometrically corrected using the ISIS software package [5]. (2) For selected CTX stereo images, exterior orientation data from reconstructed NAIF SPICE data are extracted [6]. (3) In the next step High Resolution Stereo Camera (HRSC) DTMs [7, 8, 9] are used for the rectification of CTX stereo images to reduce the search area during the image matching. Here, HRSC DTMs are used due to their higher spatial resolution when compared to MOLA DTMs. (4) The determination of coordinates of homologous points between stereo images, i.e. the stereo image matching process, consists of two steps: first, a cross-correlation to obtain approximate values and secondly, their use in a least-square matching (LSM) process in order to obtain subpixel positions. (5) The stereo matching results are then used to generate object points from forward ray intersections. (6) As a last step, the DTM-raster generation is performed using software developed at the German Aerospace Center, Berlin. Whereby only object points are used that have a smaller error than a threshold value. References: [1] Malin, M. C. et al., 2007, JGR 112, doi:10.1029/2006JE002808 [2] Broxton, M. J. et al

  1. New Vocabulary: Araneiform and Lace Terrains

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2 The south polar terrain on Mars contains landforms unlike any that we see on Earth, so much that a new vocabulary is required to describe them. The word 'araneiform' means 'spider-like.' There are radially organized channels on Mars that look spider-like, but we don't want to confuse anyone by talking about 'spiders' when we really mean 'channels,' not 'bugs.' The first subimage (figure 1) shows an example of 'connected araneiform topography,' terrain that is filled with spider-like channels whose arms branch and connect to each other. Gas flows through these channels until it encounters a vent, where is escapes out to the atmosphere, carrying dust along with it. The dark dust is blown around by the prevailing wind. The second subimage (figure 2) shows a different region of the same image where the channels are not radially organized. In this region they form a dense tangled network of tortuous strands. We refer to this as 'lace.' Observation Geometry Image PSP_002651_0930 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 18-Feb-2007. The complete image is centered at -86.9 degrees latitude, 97.2 degrees East longitude. The range to the target site was 268.7 km (167.9 miles). At this distance the image scale is 53.8 cm/pixel (with 2 x 2 binning) so objects 161 cm across are resolved. The image shown here has been map-projected to 50 cm/pixel . The image was taken at a local Mars time of 04:56 PM and the scene is illuminated from the west with a solar incidence angle of 86 degrees, thus the sun was about 4 degrees above the horizon. At a solar longitude of 186.4 degrees, the season on Mars is Northern Autumn.

  2. AFTI/F16 terrain-aided navigation system

    Energy Technology Data Exchange (ETDEWEB)

    Boozer, D.D.; Lau, M.K.; Fellerhoff, J.R.

    1985-01-01

    A recursive, real-time, terrain-aided navigation algorithm, AFTI/SITAN, was designed for use on the Advanced Fighter Technology Integration (AFTI) F16 aircraft. The algorithm implemented in a Zilog Z8001 microprocessor, can reliably locate the aircraft's position within a 926-m (0.5 nm) CEP circle and accurately estimate its position continuously (3 Hz). The design and execution of the algorithm are described, and simulation results using actual flight test data are presented. A median accuracy of less than 100 m was achieved over gently rolling, forested terrain using cartographic-based digital terrain elevation data.

  3. Path planning for complex terrain navigation via dynamic programming

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, K.S.; Driessen, B.J.

    1998-12-31

    This work considers the problem of planning optimal paths for a mobile robot traversing complex terrain. In addition to the existing obstacles, locations in the terrain where the slope is too steep for the mobile robot to navigate safely without tipping over become mathematically equivalent to extra obstacles. To solve the optimal path problem, the authors use a dynamic programming approach. The dynamic programming approach utilized herein does not suffer the difficulties associated with spurious local minima that the artificial potential field approaches do. In fact, a globally optimal solution is guaranteed to be found if a feasible solution exists. The method is demonstrated on several complex examples including very complex terrains.

  4. Trace element geochemistry and petrogenesis of the granitoids and high-K andesite hosting gold mineralisation in the Archean Musoma-Mara Greenstone Belt, Tanzania

    Science.gov (United States)

    Kazimoto, Emmanuel Owden; Ikingura, Justinian R.

    2014-03-01

    Modern and ancient active continental margins are well known for their potential for hosting important gold deposits. The Neoarchean Musoma-Mara Greenstone Belt of the Tanzania Craton is also known for hosting several important gold deposits. Previous geochemical studies of the belt demonstrated that the rocks formed along Neoarchean convergent margins. The host rocks of the three important deposits in this belt had not yet been geochemically investigated. Therefore, we studied the host rocks of the Gokona, Nyabigena and Nyabirama gold deposits in the Neoarchean Musoma-Mara Greenstone Belt of the Tanzania Craton to determine the tectonic setting of their formation and constrain their petrogenesis. The host rocks of the Gokona and Nyabigena deposits are classified as high-K andesite, whereas the host rocks of the Nyabirama deposit are classified primarily as trondhjemite and granite and minor granodiorite (TGG). The high-K andesite and TGG were formed in an active continental margin similar to that of other Neoarchean volcanic rocks found in the Musoma-Mara Greenstone Belt. The host rocks contain low Ni and Cr concentrations and are characterised by negative Eu anomalies (Eu/Eu* = 0.67-0.72 and 0.17-0.6). The chondrite-normalised rare earth element (REE) patterns of the rocks display strong enrichment in light REEs over heavy REEs (high-K andesite (La/Yb)N = 21.7-35.6, and TGG (La/Yb)N = 2.4-94.4). Moreover, the primitive normalised diagrams show enrichment in large-ion lithophile elements (Ba, Rb, Th and K), negative Nb and Ta anomalies and depletion in heavy rare earth elements and high field-strength elements (Y and Ti). The high-K andesite has a Nb/Ta value close to that of depleted mantle (mean = 15.0), lower Zr/Sm values (19.4-30.6) and higher concentrations of REEs, large ion lithophile elements, Sr (607 ppm) and Y than in the TGG. The TGG has a low mean Nb/Ta value (13.2) and Sr concentration (283 ppm) and a lower amount of HREEs and higher values of Zr

  5. Terrain mapping camera for Chandrayaan-1

    Indian Academy of Sciences (India)

    A S Kiran Kumar; A Roy Chowdhury

    2005-12-01

    The Terrain Mapping Camera (TMC)on India ’s first satellite for lunar exploration,Chandrayaan-1, is for generating high-resolution 3-dimensional maps of the Moon.With this instrument,a complete topographic map of the Moon with 5 m spatial resolution and 10-bit quantization will be available for scienti fic studies.The TMC will image within the panchromatic spectral band of 0.4 to 0.9 m with a stereo view in the fore,nadir and aft directions of the spacecraft movement and have a B/H ratio of 1.The swath coverage will be 20 km.The camera is configured for imaging in the push broom-mode with three linear detectors in the image plane.The camera will have four gain settings to cover the varying illumination conditions of the Moon.Additionally,a provision of imaging with reduced resolution,for improving Signal-to-Noise Ratio (SNR)in polar regions,which have poor illumination conditions throughout,has been made.SNR of better than 100 is expected in the ± 60° latitude region for mature mare soil,which is one of the darkest regions on the lunar surface. This paper presents a brief description of the TMC instrument.

  6. All-terrain self-leveling wheelchair.

    Science.gov (United States)

    Schofield, Andrew; Barrett, Steven

    2014-01-01

    Limited mobility is something that affects approximately 6.8 million Americans. Approximately 1.7 million are using wheelchairs or scooters of some kind to enhance mobility. Everyday obstacles present a challenge to those in a wheelchair. Also, outdoor environments such as campsites, lakes, or even grass fields provide additional challenges for those with limited mobility. This project provides a solution to some of the limitations faced by those in wheelchairs. The wheels and tires of the wheelchair allow navigation through most terrains such as grass, gravel, and sand. Furthermore, as a wheelchair climbs or descends a hill it becomes unstable and the user risks tipping the wheelchair causing injury or even death. The self-leveling wheelchair uses an accelerometer to determine its angle of inclination and depending on user interface choices will display the angle or raise the seat with linear actuators to keep the seat level. This will keep the center of gravity towards the front of the chair when going up a hill and towards the back of the chair when going down a hill. This enhanced stability will give the user the confidence and ability to go places where most traditional wheelchairs can not. The chair has the ability to self-level at up to 45 degree and can provide a manual lift of 6 inches. The design presented in this report is patent pending.

  7. Wind and diffusion modeling for complex terrain

    Energy Technology Data Exchange (ETDEWEB)

    Cox, R.M.; Sontowski, J.; Fry, R.N. Jr. [and others

    1996-12-31

    Atmospheric transport and dispersion over complex terrain were investigated. Meteorological and sulfur hexafluoride (SF{sub 6}) concentration data were collected and used to evaluate the performance of a transport and diffusion model coupled with a mass consistency wind field model. Meteorological data were collected throughout April 1995. Both meteorological and concentration data were measured in December 1995. The data included 11 to 15 surface stations, 1 to 3 upper air stations, and 1 mobile profiler. A range of conditions was encountered, including inversion and post-inversion breakup, light to strong winds, and a broad distribution of wind directions. The models used included the SCIPUFF (Second-order Closure Integrated Puff) transport and diffusion model and the MINERVE mass consistency wind model. Evaluation of the models was focused primarily on their effectiveness as a short term (one to four hours) predictive tool. These studies showed how they can be used to help direct emergency response following a hazardous material release. For purposes of the experiments, the models were used to direct the deployment of mobile sensors intended to intercept and measure tracer clouds.

  8. Reorienting with terrain slope and landmarks.

    Science.gov (United States)

    Nardi, Daniele; Newcombe, Nora S; Shipley, Thomas F

    2013-02-01

    Orientation (or reorientation) is the first step in navigation, because establishing a spatial frame of reference is essential for a sense of location and heading direction. Recent research on nonhuman animals has revealed that the vertical component of an environment provides an important source of spatial information, in both terrestrial and aquatic settings. Nonetheless, humans show large individual and sex differences in the ability to use terrain slope for reorientation. To understand why some participants--mainly women--exhibit a difficulty with slope, we tested reorientation in a richer environment than had been used previously, including both a tilted floor and a set of distinct objects that could be used as landmarks. This environment allowed for the use of two different strategies for solving the task, one based on directional cues (slope gradient) and one based on positional cues (landmarks). Overall, rather than using both cues, participants tended to focus on just one. Although men and women did not differ significantly in their encoding of or reliance on the two strategies, men showed greater confidence in solving the reorientation task. These facts suggest that one possible cause of the female difficulty with slope might be a generally lower spatial confidence during reorientation.

  9. Risk terrain modeling predicts child maltreatment.

    Science.gov (United States)

    Daley, Dyann; Bachmann, Michael; Bachmann, Brittany A; Pedigo, Christian; Bui, Minh-Thuy; Coffman, Jamye

    2016-12-01

    As indicated by research on the long-term effects of adverse childhood experiences (ACEs), maltreatment has far-reaching consequences for affected children. Effective prevention measures have been elusive, partly due to difficulty in identifying vulnerable children before they are harmed. This study employs Risk Terrain Modeling (RTM), an analysis of the cumulative effect of environmental factors thought to be conducive for child maltreatment, to create a highly accurate prediction model for future substantiated child maltreatment cases in the City of Fort Worth, Texas. The model is superior to commonly used hotspot predictions and more beneficial in aiding prevention efforts in a number of ways: 1) it identifies the highest risk areas for future instances of child maltreatment with improved precision and accuracy; 2) it aids the prioritization of risk-mitigating efforts by informing about the relative importance of the most significant contributing risk factors; 3) since predictions are modeled as a function of easily obtainable data, practitioners do not have to undergo the difficult process of obtaining official child maltreatment data to apply it; 4) the inclusion of a multitude of environmental risk factors creates a more robust model with higher predictive validity; and, 5) the model does not rely on a retrospective examination of past instances of child maltreatment, but adapts predictions to changing environmental conditions. The present study introduces and examines the predictive power of this new tool to aid prevention efforts seeking to improve the safety, health, and wellbeing of vulnerable children.

  10. 八种药用植物精油对谷蠹成虫的熏蒸活性%Fumigant activities of eight essential oils of herb plants against Rhizopertha dominica(Fab.)adults

    Institute of Scientific and Technical Information of China (English)

    黄衍章; 李世广; 操海群; 巢道平; 周倩

    2011-01-01

    The fumigant activities of eight essential oils of herb plants against adults of Rhizopertha dominica (Fab.) were tested in the sealed triangular flask. The result indicated that Illicium verum, Foeniculum vulgare and Acorus gramineus oils were possessed of good fumigant activities against the tested pests, especially the Illicium verum oils. Under the condition of empty-storehouse-imitation, the Illicium verum and Foeniculum vulgare oils showed excellent fumigant activities against the tested pests, and the LC50 to R. Dominica (Fab.) after treatment for 3 days were 2.88 uL-L"1 and 4.02 μL·L-1, respectively. Of all eight herb plants essential oils, only Illicium verum showed good fumigant activities under the condition of real-storehouse-imitation, and the oil produced 92.37% corrected mortalities of pests at 166.67 μL·L-1 after treatment for 10 days. Further bioassay showed the LC50 of Illicium verum oil against R. Dominica (Fab.) after treatment for 14 days under the condition of real-storehouse-imitation was 67.01 uL·L-1-1.%采用三角瓶密闭熏蒸法,测试了8种药用植物精油在空仓和实仓模拟条件下对谷蠹成虫的熏蒸活性.结果表明,8种植物精油以八角茴香,小茴香和石菖蒲时试虫的熏杀效果较好,尤以八角茴香精油的熏杀效果最佳.空仓模拟条件下,八角茴香和小茴香精油均对谷蠹成虫表现出很高的熏杀活性,其熏蒸处理3d后的LC50分别为2.88 μL·L-1和4.02 μL·L-1.实仓模拟条件下,8种植物精油仅以八角茴香的熏蒸效果较好,其166.67 μL·L-1熏蒸处理10d后试虫的校正死亡率为92.37%,实仓模拟熏蒸处理14d后的LC50为67.01 μL·L-1.

  11. DCS Terrain Submission for New Castle County, DE

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  12. DCS Terrain Submittal for Spalding County, Georgia, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  13. DCS Terrain Submission for Clay County, AR, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  14. DCS Terrain Submittal for Washita County, Oklahoma, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  15. Lunar All-Terrain Utility Vehicle for EVA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC proposes to develop a new type of planetary rover called a Lunar All-terrain Utility Vehicle ("Lunar ATV") to assist extra-vehicular activities...

  16. Classification of Mars Terrain Using Multiple Data Sources

    Data.gov (United States)

    National Aeronautics and Space Administration — Classification of Mars Terrain Using Multiple Data Sources Alan Kraut1, David Wettergreen1 ABSTRACT. Images of Mars are being collected faster than they can be...

  17. DCS Terrain for Wilcox County GA MapMod08

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix M: Data Capture Standards, describes the digital topographic data that was used to create...

  18. DCS Terrain Submission for Logan County, AR, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  19. DCS Terrain Submission for Baxter County, AR, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Terrain data, as defined in FEMA Guidelines and Specifications, Appendix N: Data Capture Standards, describes the digital topographic data that was used to create...

  20. Lunar All-Terrain Utility Vehicle for EVA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC proposes to develop a new type of planetary rover called a Lunar All-terrain Utility Vehicle ("LATUV") to assist extra-vehicular activities in...