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Land-Use Impact and Nitrate Analysis to Validate DRASTIC Vulnerability Maps Using a GIS Platform of Pablillo River Basin, Linares, N.L., Mexico

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International Journal of Geosciences 2014年第12期5卷 1468-1489页

作者： René Alberto Dávila Pórcel Christoph Schüth Héctor De León-Gómez Andreas Hoppe Rowen Lehné Facultad de Ingeniería Civil Universidad Autónoma de Nuevo León México Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza México institut fur angewandte geowissenschaften Technische Universitat Darmstadt Schnittspahnstra&szlig e 9 Darmstadt Deutschland

Preventive management of groundwater resources and their protection against pollution is one of the major challenges of our society. Groundwater systems are related with the surficial processes like territorial administration that is one of the most important tasks into the human development, because it involves serious problems to define the spatial medium, the industrial site-selection and the land-use allocation. Land-use and anthropogenic distribution could be the origin of the emission of pollutants that constitutes a serious health risk in urban areas. Nitrate was used as a pollution indicator in the Pablillo River Basin (PRB), to know the evolution of groundwater quality between 1981 and 2009 using GIS platform linked to vulnerability maps of DRASTIC (Depth to the water table;net groundwater Recharge;Aquifer type;Soil type;Topography;Impact of the vadose zone and hydraulic Conductivity of the saturated zone). The study area is centered on the Linares city;changes in aquifer vulnerability were assessed over time on two stages (2007 and 2001). In both cases, depth from surface to groundwater plays an important role by being the most dynamic variable over time. This study shows that the depth of water table is the key factor in the evaluation of groundwater vulnerability. The significance of land-use impact in contamination process called Index of Pollution Risk (IPR) and nitrate distribution process in the aquifer system was used as anthropogenic indicator together with the IPR in order to associate the land-use, the aquifer-vulnerability and human-activities. The final map of IPR allows determining possible polluted zones verified by high nitrate contents over the aquifer system. Land-use proved to be an important parameter necessary to correct the vulnerability maps using the DRASTIC method. This assessment is valid for situations where a specific time is defined because six of seven parameters change their properties in a very long term. The IPR-map could be

关键词： Vulnerability Maps DRASTIC Land Use Nitrate GIS

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Multilevel Preconditioners for the Interior Penalty Discontinuous Galerkin Method ii-Quantitative Studies

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Communications in Computational Physics 2009年第2期5卷 296-325页

作者： Kolja Brix Martin Campos Pinto Wolfgang Dahmen Ralf Massjung institut fur Geometrie und Praktische Mathematik RWTH Aachen52056 AachenGermany Universite Louis Pasteur Institut de Recherche Mathematique AvanceeCNRS UMR 750167084 StrasbourgFrance

This paper is concerned with preconditioners for interior penalty discontinuous Galerkin discretizations of second-order elliptic boundary value *** extend earlier related results in[7]in the following *** concrete realizations of splitting the nonconforming trial spaces into a conforming and(remaining)nonconforming part are identified and shown to give rise to uniformly bounded condition *** asymptotic results are complemented by numerical tests that shed some light on their respective quantitative behavior.

关键词： Interior penalty method energy-stable splittings admissible averaging operators frames multilevel Schwarz preconditioners discontinuous Galerkin methods

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Trace fossils of an amalgamated storm-bed succession from the Jurassic of the Kachchh Basin,India:The significance of time-averaging in ichnology

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Journal of Palaeogeography 2018年第1期7卷 14-31页

作者： Franz To Fürsich Alfred Uchman Matthias Alberti Dhirendra K.Pandey GeoZentrum Nordbayern Fachgruppe PalaoUmweltFriedrich-Alexander-Universitat Erlangen-Numberg Loewenichstra■e 2891054 ErlangenGermany institute of Geological Sciences Jagiellonian UniversityGronostajowa 3a30-387KrakowPoland institut fur geowissenschaften Christian-Albrechts-Universitat zu KielLudewig-Meyn-Stral3e 1024118Kiel Germany Earth and Planetary Sciences GrouplPalaeontology Manipal Center for Natural SciencesManipal University Manipal 576104KarnatakaIndia

The uppermost part of the Upper Bathonian Sponge Limestone member, Patcham Formation, of the Jhura Dome of Kachchh Mainland is a thickening-and shallowing-upward succession topped by medium-to thick-bedded hummocky cross-stratified grainstones deposited by storm waves. Occasionally, thin, commonly lenticular, intraclastic-bioclastic silty marl intercalations between the grainstones are highly bioturbated, in contrast to the grainstones, in which, for the most part, trace fossils occur scattered. Large exposures of bedding planes of the grainstones allow the detailed investigation of ichnological features, whereas the high density of traces in the soft marls precludes the identification of any ichnotaxa. Eighteen ichnotaxa have been recorded including Ophiomorpha, Thalassinoides, Taenidium, Gyrophyllites, Chondrites, Dactyloidites, Teichichnus, Bolonia, and Ancorichnus. Except for Ophiomorpha nodosa and Thalassinoides, which generally indicate moderate to high energy conditions and are the dwelling burrows of suspension-feeding to omnivorous crustaceans, the ichnotaxa represent a deposit-feeding behaviour of their producers and thus are characteristic of low-energy environments. The trace fossils form three ichnoassemblages characterized by(1) Ophiomorpha nodosa and Thalassinoides suevicus,(2)?Thalassinoides isp. A, Taenidium, and Bolonia lata,and(3) Ancorichnus. The dominance of traces of deposit-feeders in rocks indicative of high-energy events is counterintuitive and points to their non-contemporaneity. The sediments were deposited during brief highenergy events, whereas the trace fossils were produced when, after waning of storms low-energy conditions prevailed. This time-averaging is particularly pronounced in trace fossils that extend vertically downwards and may reach strata deposited under distinctly different conditions. Thus, environmental interpretations based on trace fossils should refer to colonisation surfaces rather than to the sediment surrounding th

关键词： Trace fossils Middle Jurassic Kachchh Basin Taxonomy Time averaging Ichnology

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Transport coefficients of a massive pion gas

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Chinese Physics C 2010年第9期34卷 1453-1455页

作者： D.Fernández-Fraile A.Gómez Nicola institut für Theoretische Physik Johann Wolfgang Goethe-Universitt Departamento de Física Teórica ii Universidad Complutense

We review our main results concerning the transport coefficients of a light meson gas,in particular we focus on the case of a massive pion *** order results according to the chiral power-counting are presented for the DC electrical conductivity,thermal conductivity,shear viscosity,and bulk *** also comment on the possible correlation between the bulk viscosity and the trace anomaly in QCD,as well as the relation between unitarity and a minimum of the quotient η/s near the phase transition.

关键词： transport coefficients heavy-ion collisions Chiral Perturbation Theory

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Recombination mechanisms and thermal droop in AlGaN-based UV-B LEDs

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Photonics Research 2017年第2期5卷 44-51页

作者： CARLO DE SANTI MATTEO MENEGHINI DESIREE MONTI JOHANNES GLAAB MARTIN GUTTMANN JENS RASS SVEN EINFELDT FRANK MEHNKE JOHANNES ENSLIN TIM WERNICKE MICHAEL KNEISSL GAUDENZIO MENEGHESSO ENRICO ZANONI Department of Information Engineering University of Padova Ferdinand-Braun-institut Leibniz-Institut fur Hochstfrequenztechnik Technische Universitat Berlin Institut für Festkorperphysik

This paper reports a comprehensive analysis of the origin of the electroluminescence(EL)peaks and of the thermal droop in UV-B AlGaN-based *** carrying out spectral measurements at several temperatures and currents,(i)we extract information on the physical origin of the various spectral bands,and(ii) we develop a novel closed-form model based on the Shockley–Read–Hall theory and on the ABC rate equation that is able to reproduce the experimental data on thermal droop caused by non-radiative recombination through deep *** the samples under test,the three EL bands are ascribed to the following processes:band-to-band recombination in the quantum wells(main EL peak),a parasitic intra-bandgap radiative transition in the quantum well barriers,and a second defect-related radiative process in the p-AlGaN superlattice.

关键词： Recombination mechanisms and thermal droop in AlGaN-based UV-B LEDs Ga AlGaN EBL SRH UV

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Detrital Zircon Ages and Hf-Nd Isotopic Composition of Neoproterozoic Sedimentary Rocks in the Yangtze Block:Constraints on the Deposition Age and Provenance

Detrital Zircon Ages and Hf-Nd Isotopic Composition of Neopr...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Wolfgang Siebel institut fr geowissenschaften Universitt Tbingen

The South China craton was formed by collision of the Yangtze and Cathaysia blocks during the Neoproterozoic Jiangnan orogeny(also termed the Jingnin or Sibao orogeny in Chinese literature).Basement rocks within the Yangtze block consist mainly of Proterozoic sediments of the Lengjiaxi and Banxi groups.U-Pb ages of detrital zircons obtained by the laser ablation inductively coupled plasma mass spectrometry dating technique imply that the deposition of the Lengjiaxi Group continued until the *** youngest detrital zircons suggest a minimum deposition age of 30 Ma for the Lengjiaxi Group and an initial deposition age of 785±12 Ma for the Banxi Group,indicating a temporal hiatus of 48±13 Ma between these Neoproterozoic sedimentary rocks distributed in northwestern Hunan Province,South China *** zircons from both the Lengjiaxi and Banxi groups have a wide range ofε(t) values from -12 to 14.2 and a continuous Nd and Hf model age spectrum from～820 Ma to 2200 *** ages of many detrital zircon grains reach up to ca.2.9-3.5 Ga,indicating that both juvenile mantle material and ancient crust provided sedimentary *** is also consistent with the Nd isotopic signature of sedimentary rocks recorded in the Lengjiaxi Group,suggesting a back-arc tectonic *** Banxi Group has slightly enriched Nd isotopic signatures relative to the Lengjiaxi Group,implying a higher percentage of old continental material in the sedimentary *** with previously published data,new results help us to reconstruct the Neoproterozoic tectonic evolution of the South China craton.

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An abrupt cooling event early in the last interglacial in the northern South China Sea

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Science China Earth Sciences 2001年第10期44卷 865-870页

作者：涂霞郑范王吉良蔡慧梅汪品先 C.Bühring M.Sarnthein 1. The South China Sea institute of Oceanology Chinese Academy of Sciences 510301 Guangzhou China 2. Key Laboratory of Marine Geology Ministry of Education Tongji University 200092 Shanghai China 3. institut für geowissenschaften Universit?t Kiel Germany

The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49– 137.6 mcd at ODP Site 1144 on the continental slope of northern South China Sea reveals an abrupt cooling event of sea surface temperature (SST) during the last interglacial (MIS 5.5, i.e. 5e). The dropping range of the winter SST may come to 7.5°C corresponding to 1.2‰ of the δ18O value of sea surface water. This event is comparable with those discovered in the west Europe and the northern Atlantic Ocean, but expressed in a more intensive way. It is inferred that this event may have been induced by middle- to low-latitude processes rather than by polar ice sheet change. Since the Kuroshio-index speciesPulleniatina obliquiloculata displayed the most distinct change at the event, it may also be related to the paleoceanographic change of the low-latitude area in the western Pacific Ocean. This event can be considered as one of “Younger Dryas-style coolings” and is indicative of climate variability of the last interglacial stage.

关键词： northern South China Sea last interglacial period sudden cooling event MIS 5.5 climate variability

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High-pressure granulites in the Sanggan area,North China craton:metamorphic evolution,P-T paths and geotectonic significance

High-pressure granulites in the Sanggan area,North China cra...

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中国科学院地质与地球物理研究所2002学术年会

作者： P.J.O’Brien institut fuer geowissenschaften Universitaet Potsdam601553 PotsdamGermany

High-pressure basic granulites are widely distributed as enclaves and sheet-like blocks in the Huaian TTG gneiss terrane in the Sanggan area of the Central Zone of the North China craton. Four stages of the metamorphic history have been recognized in mineral assemblages based on inclusion,exsolution and reaction textures integrated with garnet zonation patterns as revealed by compositional maps and compositional profiles.P-T conditions for each metamorphic stage were obtained using thermodynamically- and experimentally-calibrated *** low-Ca core of growth-zoned garnet,along with inclusion minerals,defines a prograde assemblage (M1) of garnet+clinopyroxene+plagioclase+quartz,yielding 700℃and 10 *** peak of metamorphism at about 750-870℃and 11-14.5 kbar(M2) is defined by high-Ca domains in garnet interiors and inclusion minerals of clinopyroxene,plagioclase and *** or coronas of orthopyroxene+plagioclase±magnetite around garnet porphyroblasts indicate garnet breakdown reactions(M3) at conditions around 770-830℃and 8.5-10.5 *** exsolution lamellae in clinopyroxene and kelyphites of amphibole+plagioclase around garnet formed during cooling process at about 500-650℃and 5.5-8 kbar(M4).These results help define a sequential P-T path containing prograde,near-isothermal decompression(ITD) and near-isobaric cooling(IBC) stages. The clockwise hybrid ITD and IBC P-T paths of the HP granulites in the Sanggan area imply a model of thickening followed by extension in a collisional ***,the relatively high-pressures(6-14.5 kbar) of the four metamorphic stages and the geometry of the P-T paths suggest that the HP granulites,together with their host Huaian TTG gneisses,represent the lower-plate in a crust thickened during *** corresponding upper-plate might be the tectonically overlying Khondalite series,which was subjected to medium- to low-pressure(MP/LP: 7-4 kbar) granulite facies metamorphism with a clock

关键词： High-pressure granulite reaction textures P-T paths Paleoproterozoic North China craton

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Comparison of climatic threshold of geographical distribution between dominant plants and surface pollen in China

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Science China Earth Sciences 2008年第8期51卷 1107-1120页

作者： CHEDDADI Rachid BEAUDOUIN Celia institut des Sciences de l'Evolution Universite Montpellier ii Montpellier 34095France Department of Earth Sciences Sun Yat-sen UniversityGuangzhou 510275China

The geographical distribution of dominant plant species in China was georeferenced and climatic variables were interpolated into all ***,the percentage distributions of principal pollen taxa based on 1860 surface pollen sites in China were selected and the related climate values were interpolated with the same method. The geographical and climatic comparison between the two data-sets indicated that the climate threshold of most pollen taxa from surface pollen is coherent with plant distributions. The climatic envelopes of dominant plant are mostly accordant with those of pollen taxa at certain levels. However, some distinct offsets of the climate ranges exist between the two datasets for most pollen taxa identified at family level, such as Ericaceae,Asteraceae, Poaceae and Chenopodiaceae. The present study provides for the first time rich information on temperature and precipitation in relation to pollen and plant distribution based on the datasets on a continental scale useful for global ecological modeling and Quaternary palaeoclimate reconstruction.

关键词： surface pollen dominant plant species geographical distribution climate global changes

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东西特提斯晚白垩世深水底栖有孔虫生物相和岩相(英文)

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地学前缘 2005年第2期12卷 81-103页

作者： Wolfgang KUHNT Ann HOLBOURN institut für geowissenschaften der Christian-Albrechts Universitt zu Kiel Olshausenstr. 40 24118 Kiel GermanyInstitut für Geowissenschaften der Christian-Albrechts Universitt zu Kiel Olshausenstr. 40 24118 Kiel Germany

白垩纪深水古海洋学研究仍处于早期发展阶段,一方面是由于来自钙质底栖有孔虫的稳定同位素和地球化学数据的缺乏,其原因在于白垩纪高碳酸盐补偿深度;另一方面在于深水有机质胶结有孔虫示踪古海洋还没有充分发展起来。深海环境深水胶结... 详细信息

白垩纪深水古海洋学研究仍处于早期发展阶段,一方面是由于来自钙质底栖有孔虫的稳定同位素和地球化学数据的缺乏,其原因在于白垩纪高碳酸盐补偿深度;另一方面在于深水有机质胶结有孔虫示踪古海洋还没有充分发展起来。深海环境深水胶结有孔虫的分布主要取决于碳酸盐可利用状况、原始生产的输入通量、深水交换、环境波动(深海洋流、浊流和快速沉积事件)和底层沉积类型,因此对于重建深海环境具有非常巨大的潜力。东、西特提斯Campanian Maastrichtian深水底栖有孔虫组合的统计分析揭示出6个生物相,代表着明显不同的沉积环境。包括:深海红色泥岩与矮小深海生物组合(生物相1);红色深海泥灰岩(“Couches Rouges”相),含钙质胶结有孔虫组合(生物相3);深水远洋灰岩(“Scaglia Rossa”相),含易碎的Rhizammina组合(生物相2);绿色灰色半远洋泥灰岩,含适应高输出通量生物组合(生物相4);半远洋泥岩和粉砂岩,含Aschemocella Nothia 组合(生物相5);陆源浊积层序,含“复理石型”Rhabdammina组合(生物相6)。Campanian Maastrichtian红色氧化深水环境动物组合与现今深海类似,而白垩纪贫氧深海环境胶结组合在现今无法找到相类似物。随着古生态信息的增加和数据库的扩展,深水胶结有孔虫有望成为揭示古海洋条件的重要工具,尤?

关键词：白垩纪深水胶结有孔虫生物相特提斯海

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