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Arsenic variability and groundwater age in three water supply wells in southeast New Hampshire

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Geoscience Frontiers 2019年第5期10卷 1669-1683页

作者： Joseph P.Levitt James R.Degnan Sarah M.Flanagan Bryant C.Jurgens U.S.geological survey

Three wells in New Hampshire were sampled bimonthly over three years to evaluate the temporal variability of arsenic concentrations and groundwater *** samples had measurable concentrations of arsenic throughout the entire sampling period and concentrations in individual wells had a mean variation of more than 7 μg/*** time series data from this sampling effort showed that arsenic concentrations ranged from a median of 4 mg/L in a glacial aquifer well (SGW-65) to medians of 19 μg/L and 37 μg/L in wells (SGW-93 and KFW-87) screened in the bedrock aquifer,*** high arsenic concentrations were associated with the consistently high pH (median ≥- 8) and low dissolved oxygen (median <0.1 mg/L) in the bedrock aquifer wells,which is typical of fractured crystalline bedrock aquifers in New *** from the glacial aquifer often has high dissolved oxygen,but in this case was consistently *** pH also is generally acidic in the glacial aquifer but in this case was slightly alkaline (median =7.5).Also,sorption sites may be more abundant in glacial aquifer deposits than in fractured bedrock which may contribute to lower arsenic *** groundwater ages were less than 50 years old in all three wells and correlated with conservative tracer concentrations,such as chloride;however,mean age was not directly correlated with arsenic *** concentrations at KFW-87 did correlate with water levels,in addition,there was a seasonal pattern,which suggests that either the timing of or multiple sampling efforts may be important to define the full range of arsenic concentrations in domestic bedrock *** geochemically reduced conditions and alkaline pHs are common to both bedrock and glacial aquifer wells in this study,groundwater age correlates less strongly with arsenic concentrations than geochemical *** also is evidence of direct hydraulic connection between the glacial and bedrock aquifers,which can influe

关键词： Arsenic variability Geochemical time series Age tracers Groundwater age modeling

Zircon U-Pb geochronology, Hf isotopic composition, and geological implications of the Neoproterozoic meta-sedimentary rocks in Suizhou-Zaoyang area, the northern Yangtze Block

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Science China Earth Sciences 2015年第11期58卷 1910-1923,1-4页

作者： YANG ZhenNing YANG KunGuang XU Yang DENG xin CHENG WanQiang LONG ZhaoYue Faculty of Earth Science China University of Geosciences Key Laboratory of Tectonics and Petroleum Resources Ministry of Education China University of Geosciences Wuhan center of geological survey China Geological Survey PowerChina Huadong Engineering Corporation

Suizhou-Zaoyang area is located in the southern Qinling-Tongbai-Dabie Orogen, China. A combined research on U-Pb ages and Lu-Hf isotopes for detrital zircons from three meta-sedimentary rocks in the Wudang Group is reported. The upper Wudang Group has a major age population of ca. 750 Ma and a sub-major of ca. 860 Ma. But the lower part only yields one age peak at ca. 2.03 Ga. In situ Lu-Hf analyses of the young age group of ca. 750 Ma for zircons from the upper Wudang Group yield an average εHt（t） value of -8.6 and two-stage Hf model ages （TDM2） from 1837 to 2230 Ma, respectively. However, zircons from the lower Wudang Group give an average εHf（t） value of 4.5 and TDM1 of 2220±22 Ma, close to the timing of zircon crystallization. Thus, it is suggested that, in the study area, the continental crust grew during the middle Paleoproterozoic and reworked during the middle Neoproterozoic, which shows the affinity to the Dabie Orogen. In addition, in the lower Wudang Group, two metamorphic zircon ages of 1992±91 and 1999±61 Ma are consistent with that of the middle Paleoproterozoic metamorphism event in the northern Yangtze Block, which may represent the assemblage of the Columbia Supercontinent. On the basis of the U-Pb ages and Hf isotopes, it is proposed that Suizhou-Zaoyang area was involved in the subduction-collision event in the middle Paleoproterozoic and the Yangtze Block was one of the components of the Paleo-Mesoproterozoic supercontinent.

关键词： detrital zircon growth and reworking of continental crust middle Paleoproterozoic northern Yangtze Block Columbia Supercontinent

A New Palynological Assemblage from the Nenjiang Formation of Dayangshu Basin, and its geological Implication

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 198-199页

作者： SUN Lei WANG Chenglong BIAN xiongfei Shenyang center of geological survey China Geological SurveyShenyang 110034LiaoningChina School of Earth Sciences Northeast Petroleum UniversityDaqing 163318HeilongjiangChina

Objective The Dayangshu Basin located in eastern Inner Mongolia,is one of the key areas for oil and gas exploration in the periphery of Songliao *** far,this basin has been poorly explored,and the basic geological research is still weak,due to the lack of high-quality paleontologic and stratigraphic *** previous oil and gas investigations were mainly focused on the Early Cretaceous ***,the Late Cretaceous Nenjiang Formation in the basin also has hydrocarbon potential according to the latest *** recent oil and gas geological survey,palynological fossils have been discovered from the Nenjiang Formation in the Dayangshu Basin,providing new evidence for biostratigraphic division and correlation.

关键词： and its geological Implication A New Palynological Assemblage from the Nenjiang Formation of Dayangshu Basin

Water resource utilization characteristics and driving factors in the Hainan Island

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Journal of Groundwater Science and Engineering 2023年第2期11卷 191-206页

作者： Dun Wang Li-xin Pei Li-zhong Zhang xi-wen Li Ze-heng Chen Yue-hu Zhou Haikou Marine geological survey center China Geological SurveyHaikou 571100China Comprehensive survey and Management center for Natural Resources China Geological SurveyBeijing 100055China Chinese Academy of geological Sciences Beijing 100037China

The scarcity of water resources caused by the unique topography and uneven rainfall distribution in Hainan Island has become a major factor restricting local development. In order to provide effective and scientific reference basis for the overall water resource utilization status and solving this problem, this study calculated the water resource utilization situation of Hainan Island from 2017 to 2021 in detail using methods including water resource ecological footprint analysis. Furthermore, a spatial correlation analysis was conducted to examine the island's water resource utilization characteristics, and the driving factors behind the changes in water resource utilization over the past five years were analyzed using the LMDI model. The results show that:(1) During the study period, the water resource ecological footprint in Hainan Island exhibited a slow growth trend, while the ecological carrying capacity showed a downward *** per capita ecological deficit of water resources remains relatively high, and the water consumption per 10 000 yuan GDP in the whole land continues to decrease, indicating that the overall pressure on water resource demand remains high with significant regional differences accompanied by the efficiency of water resource utilization steadily improving at the same time;(2) Agricultural water use accounts for the highest proportion in the entire water use structure, while ecological water use represents the smallest share, with a year-on-year increase, indicating that Hainan Island highlights the agricultural development and is increasingly conscious of the ecological environment;(3) Significant spatial differentiation in water resource utilization characteristics exists in Hainan Island, with the western region being a hot spot aggregation area for per capita water resource ecological footprint, per capita ecological carrying capacity of water resources, water consumption per 10 000 yuan GDP, while it is a cold spot cluster area fo

关键词： Ecological footprint Ecological carrying capacity Water consumption Moran'sⅠindex Cold/hot spot analysis LMDI model

Association of Sandstone-Type Uranium Mineralization in the Northern China with Tectonic Movements and Hydrocarbons

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Journal of Earth Science 2022年第2期33卷 289-307页

作者： Yin Chen Peisen Miao Jianguo Li Ruoshi Jin Hualei Zhao Lulu Chen CongWang HaoyuYu xiaoru Zhang Tianjin center China Geological SurveyTianjin 300170China Key Laboratory of Uranium Geology China Geological SurveyTianjin 300170China Cores and Samples center of Natural Resources China Geological SurveyBeijing 100192China National center of Ocean Standards and Metrology Tianjin 300112China Guangzhou Marine geological survey of Natural Resources Guangzhou 510075China Shanghai Municipal Engineering Design Institute Co.LTD. Shanghai 200092China

In the continental basins of Northern China(NC),a series of energy resources commonly co-exist in the same *** the three typical superimposed basins of different genesis in the NC,the Junggar,Ordos,and Songliao basins were chosen as the research *** favorable uraniumbearing structures are generally shown as a basin-margin slope or transition belt of uplifts with the development of faults,which are conducive to a fluid circulation *** Hercynian,Indosinian,and Yanshanian movements resulted in the development of uranium-rich intrusions which acted as the significant uranium *** main hydrocarbon source rocks are developed in the Carboniferous,Permian,Jurassic and *** mature stage of source rocks is concentrated in the Jurassic–Cretaceous,followed by the multi-stage expulsion *** by the India-Eurasian collision and the subduction of the Pacific Plate,the tectonic transformation in the Late Yanshanian and Himalayan periods significantly influenced the sandstone-type uranium *** hydrocarbon reservoirs are spatially consistent with sandstone-type uranium deposits,while the hydrocarbon expulsion events occur in sequence with sandstone-type uranium *** the periphery of the faults or the uplifts,both fluids met and formed uranium *** regional tectonic movements motivate the migration of hydrocarbon fluids and uranium mineralization,especially the Himalayan movement.

关键词： sandstone-type uranium deposits Northern China hydrocarbon reservoirs tectonic evolution fluid ore deposit geology

Response of glacier area variation to climate change in the Kaidu-Kongque river basin,Southern Tianshan Mountains during the last 20 years

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China Geology 2021年第3期4卷 389-401页

作者： Lu-chen Wang Kun Yu Liang Chang Jun Zhang Tao Tang Li-he Yin xiao-fan Gu Jia-qiu Dong Ying Li Jun Jiang Bing-chao Yang Qian Wang Key Laboratory of Groundwater and Ecology in Arid and Semi-arid Areas China Geological SurveyXi’an 710054China xi’an center China Geological SurveyXi’an 710054China School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

Glaciers are crucial water resources for arid inland rivers in Northwest *** recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on regional water *** primary role of understudying watershed scale glacier changes under changing climatic conditions is to ensure sustainable utilization of regional water resources,to prevent and mitigate glacier-related *** study maps the current(2020)distribution of glacier boundaries across the Kaidu-Kongque river basin,south slope of Tianshan Mountains,and monitors the spatial evolution of glaciers over five time periods from 2000-2020 through thresholded band ratios approach,using 25 Landsat images at 30 m *** addition,this study attempts to understand the role of climate characteristics for variable response of glacier *** results show that the total area of glaciers was 398.21 km^(2)in *** glaciers retreated by about 1.17 km^(2)/a(0.26%/a)from 2000 to *** glaciers were reducing at a significantly rapid rate between 2000 and 2005,a slow rate from 2005 to 2015,and an accelerated rate during *** meteorological data shows slight increasing trends of mean annual temperature(0.02℃/a)and annual precipitation(2.07 mm/a).The correlation analysis demonstrates that the role of temperature presents more significant correlation with glacier recession than *** is a temporal hysteresis in the response of glacier change to climate *** trend of temperature in summer proves to be the driving force behind the Kaidu-Kongque basin glacier recession during the recent 20 years.

关键词： Glacier area Climate change Remote sensing monitoring Hydrogeological survey engineering Kaidu-Kongque river basin Tianshan Mountains center Asia-Mongolian Plateau

First Record of Middle Eocene Elephant Ancestors’Footprints in the Gonjo Basin,East Tibet Plateau

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Journal of Earth Science 2024年第4期35卷 1224-1235页

作者： Asma Tahir Huazhou Yao Junaid Khan Yangui Li He Zhao Yue Yu Tang Yuan Institute of geological survey China University of GeosciencesWuhan430074China Wuhan center China Geological SurveyWuhan430205China State Key Laboratory of geological Processes and Mineral Resources Wuhan430078China Chengdu center China Geological SurveyChengdu610081China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China

It is the first time that the fossil footprints of a group of Middle Eocene elephant ancestors have been discovered in the Gonjo Basin,East Tibet *** Gonjo Formation is attributed to the Middle Eocene Epoch(U-Pb age=44.7±1.2 Ma)and consists mainly of purplish-red,medium-to coarse-grained sandstones,siltstones interbedded with mudstones,and conglomerates with sedimentary structures like ripple marks,rip-up clasts,and trough-cross bedding,suggesting fluvial-lacustrine *** group of fossil footprints has a characteristic oval-concave shape,and the toe impressions are *** fossil footprints are overstepped with a pockmarked texture resembling Proboscipeda *** than 165 fossil footprints of the group are relatively well-preserved with different diameters,which is evidence of highly social behavior and trackmakers of different ages,including calves,juveniles,adolescents,and *** size frequency of the fossil footprints enabled us to deduce the body mass,shoulder height,and hip-height distribution of the trackmakers that crossed the East Tibet Plateau 44.7 Ma *** trackmakers comprised an estimated average hip-height of 111.8 cm,an average shoulder height of 172.8 cm for males/155.9 cm for females,and an average body mass of approximately 1218.1 kg for males/907.8 kg for *** abundance of fossil footprints reveals that in the Middle Eocene Epoch,the environment was extraordinarily conducive for the elephant ancestors to live in the East Tibet region.

关键词： Proboscipeda enigmatica East Tibet Plateau Gonjo Formation fossil footprints fluvial-lacustrine

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Reconstruction the Process of Partial Melting of the Retrograde Eclogite from the North Qaidam,Western China: Constraints from Titanite U-Pb Dating and Mineral Chemistry

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Journal of Earth Science 2019年第6期30卷 1166-1177页

作者： Yuting Cao Liang Liu Wenqiang Yang Yuan Gao xiaohui Zhu Shandong Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China XVan center of geological survey China Geological SurveyXi'an 710054China

Retrograde eclogite and garnet amphibolite of the Lüliangshan unit of the Shenglikou area,North Qaidam,were studied with emphasis on rutile and titanite.A special focus is on the formation of rutile and its corona of titanite(Ttn1)in retrograde eclogite and on coarse-grained titanite(Ttn2)from the garnet *** zirconium(Zr)-in-rutile and Zr-in-titanite thermometers,the temperatures estimated for the formation of an early generation of rutile are 823–884℃at 2.5–2.8 GPa,while 812–894℃at 1.3–1.5 GPa are derived for the formation of coronitic Ttn1 in the retrograde ***,isothermal decompression must have occurred during exhumation,which also has triggered the partial melting of the retrograde ***2 of the garnet amphibolite has high REE contents and high Th/U ratios,indicating that it is newly grown from a Ti,Ca,and LREE enriched anatectic melt derived from the partial melting of retrograde ***-ICP MS U-Pb dating yields a lower intercept age of 423±4 Ma for Ttn2,which is consistent with the granulite-facies metamorphic age of the retrograde ***,a temperature of 781–823℃at 1.0–1.2 GPa is obtained for Ttn2,which fits the P-T conditions of the HP granulite-facies metamorphic stage(P=1.07–1.24 GPa and T=774–814℃),and documents that the crystallization of the melt occurred at the granulite-facies stage at 423 *** high amount of REE of the garnet amphibolite is a consequence of the formation of Ttn2 from the *** contents and ratios of Zr and Hf in rutile and Ttn2 differ from those in the garnet amphibolite,and the whole rock Zr/Hf ratios of retrograde eclogite and garnet amphibolite are both higher than the respective ratios in rutile and Ttn2,suggesting that rutile and titanite cannot be the major carriers of Zr and Hf accounting for the high whole rock Zr/Hf ratios.

关键词： North Qaidam titanite U-Pb dating partial melting isothermal decompression element fractionation

A New Example of Retrograde Solubility Model for Carbonate Rocks

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1145-1146页

作者： LIU Lihong WANG Chunlian WANG Daming WANG Haida Oil & Gas survey China Geological Survey Oil and Gas Research center School of Earth and Space SciencesPeking University MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences China geological survey

Objective The dissolution and precipitation of carbonate during burial diagenetic process controls the reservoir property in deep buried strata. The geological process related with it has become a research focus during recent years. The most important dissolution fluids to carbonates are probably H2S and CO2 as byproducts of sulfate reduction in deep-buried setting with sulfate minerals, but carbonates are more soluble in relatively low temperature, which is the so-called retrograde solubility. Several geological processes can result in the decrease of temperature, including the upward migration of thermal fluids and tectonic uplift.

关键词： of on with well A New Example of Retrograde Solubility Model for Carbonate Rocks for