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Characteristics of B,Zn and Se in stream sediments of Tanzania and their agricultural applications:Based on 1∶1000000 geochemical survey

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china Geology 2023年第1期6卷 1-14页

作者： Kang-kang Xu Hong-wei Sun Wei Xie Fu-qing He Xiao-yang Liu Kai Sun Sheng-fei He Xing-yuan Wu Peng-hui Gong Godfrey Machumu Southern African Mining Research Institute China Geological SurveyTianjin 300170China North china center of Geoscience Innovation Tianjin 300170China Tianjin geological Mineral Testing center Tianjin 300191China geological survey of Tanzania DodomaP.O Box 903Tanzania

Tanzania is located in eastern Africa with a predominantly agricultural ecomomy,the potential for developing and utilizing cultivated land are promising,but scientific guidance is required.B,Zn and Se are essential micronutrients for plants and human body with crucial biological functions,in particular,Se is significant for human health and considered as“the king of anti-cancer”.As these elements required by human or plants are mainly absorbed from soil directly or indirectly,therefore,it is important to understand the contents and distributions of them in the soil of cultivated land for guiding agricultural *** this work,low-density geochemical survey at the scale of 1∶1000000 was carried out in Tanzania,and the results show that the concentrations of B,Zn and Se in stream sediments are low and their distributions are *** to the distributions of geological units,the existing cultivated land resources can be divided into five regions in *** with the national background values,the concentrations of B,Zn and Se are insufficient overall but enriched locally in these *** general,element concentrations in stream sediments and soil have a positive correlation because of their similar sources,which is essential in agriculture *** on the information provided by low-density geochemical data and maps,the Se-sufficient and Se-rich regions were delineated in Tanzania,where can be used to develop Se-rich ***,this paper believes that geochemical survey is a powerful tool for cultivated land evaluation,agriculture management and land development.

关键词： Stream sediment Low-density geochemical survey Geochemical map Soil of cultivated land Agricultural applications Agricultural geological survey engineering Tanzania Selenium-rich agricultural products

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Zircon U-Pb and geochemical analyses for leucocratic intrusive rocks in pillow lavas in the Danfeng Group,north Qinling Mountains,china

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Science china Earth Sciences 2008年第2期51卷 249-262页

作者： Yan QuanRen Chen JunLu Wang ZongQi Yan Zhen Wang Tao Li QiuGen Zhang ZongQing Jiang ChunFa Institute of Geology Chinese Academy of Geological Sciences (CAGS) Beijing 100037 China Beijing SHRIMP center CAGS Beijing 100037 China Xi’an Institute of Geology and Mineral Resources China Geological Survey Xi’an 710054 China

Field observation showed that there are many irregular leucocratic intrusive rocks in pillow lavas in the Danfeng Group in the Xiaowangjian area, north Qinling orogenic belt. Photomicrographs indicated that the protol... 详细信息

关键词： Danfeng Group pillow lava leucocratic intrusive rock geochemistry and isotope SHRIMP U-Pb dating

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Risk Assessment and Treatment Countermeasures for the Barrier Lakes of Wenchuan Earthquake on May 12^(th),2008

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 826-833页

作者： ZHANG Fawang ZHANG Zhaoji HAN Zhantao SUN Jianping XIAO Guoqiang Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Zhengding 050803 China center of Hydrogeology and Environmental Geology China Geology Survey Baoding 071051 China Tianjin center of china Geology survey Tianjin 300170 China

This paper introduced the first hand investigation results of the risk and treatment measures for the barrier lakes triggered by the earthquake of Wenchuan. Characteristics of 10 barrier lakes were investigated and analyzed; procedure and methods for barrier lake treatment were brought forward. The dams of the barrier lakes can be classified as two classes： block rock in the south and loose deposit in the north. All the barrier dams were stable at the time of investigation, but water drainage channel needed to be constructed and to be protected from blockage or collapse. After the rain season of 2008, some dams needed to be consolidated, and change the barrier lakes to reservoirs.

关键词： Wenchuan earthquake barrier lake geological environment

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Effects and mechanism of igneous rock on selenium in the tropical soil-rice system in Hainan Province, South china

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china Geology 2022年第1期5卷 1-11页

作者： Xiu-jin Liu Ke Yang Fei Guo Shi-qi Tang Ying-han Liu Li Zhang Hang-xin Cheng Fei Liu Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesLangfang 065000China Key Laboratory of Geochemical Cycling of Carbon and Mercury in the Earth’s Critical Zone Chinese Academy of Geological SciencesLangfang 065000China Research center of Geochemical survey and Assessment on land Quality China Geological SurveyLangfang 065000China

To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,South *** contents of Se in soils derived from granitoid and basalt are,respectively,0.19±0.12 mg/kg and 0.34±0.39 mg/kg,which are much higher than Se contents in granitoid and *** shows remarkable enrichment from granitoid and basalt to *** mobile fraction of Se in soils derived from granitoid is 0.0100±0.0034 mg/kg,which is significantly higher than that of basalt(0.0058±0.0039 mg/kg).Although soil derived from basalt shows higher Se contents,Se contents in rice samples,mobile fractions of Se in soils,and biological concentration factor(BCF)is similar or even lower than that from *** consist of calcic plagioclase and pyroxene,and are much richer in Fe,Al,and Ca than ***,the basalt-derived soils have higher goethite,hematite,kaolinite,cation exchange capacity(CEC)content,and higher p H than the granitoid-derived soils,which result in higher adsorption capacity for Se and relatively lower Se *** derived from granitoid and basalt in tropical regions are beneficial to produce Se-rich rice.

关键词： Selenium Granitoid Basalt Soil properties Tropical soil Se-rich rice Agricutural geological survey engineering Hainan Province china

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Preliminary results of environmental monitoring of the natural gas hydrate production test in the South china Sea

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china Geology 2018年第2期1卷 202-209页

作者： Jian-liang Ye Xu-wen Qin Hai-jun Qiu Qian-yong Liang Yi-fei Dong Jian-gong Wei Hai-long Lu Jing-an Lu Yao-hong Shi Chao Zhong Zhen Xia Guangzhou Marine geological survey China Geological SurveyGuangzhou 510075China Gas Hydrate Engineering Technology center China Geologtcal SurveyGuangzhou 510075China College of Engineering Peking UniversityBeijing 100871China

Natural gas hydrate (NGH)is considered as one of the new clean energy sources of the 21st century with the highest *** environmental issues of NGH production have attracted the close attention of scientists in various *** May 10 to July 9,2017,the first offshore NGH production test in the South china Sea (SCS)was conducted by the china geological *** addition,environmental security has also been effectively guaranteed via a comprehensive environmental monitoring system built during the NGH production *** monitoring system considered sea-surface atmosphere methane and carbon dioxide concentrations,dissolved methane in the sea water column,and the seafloor physical oceanography and marine chemistry *** whole process was monitored via multiple means, in multiple layers,in all domains,and in real *** the production test,an environmental investigation was promptly conducted to evaluate the environmental impact of the NGH production test. The monitoring results showed that the dissolved methane concentration in seawater and the near-seabed environment characteristics after the test were consistent with the background values,indicating that the NGH production test did not cause environmental problems such as methane leakage.

关键词： South china Sea Natural gas hydrate Production test Methane leakage Environmental momtoring

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Holocene sea level trend on the west coast of Bohai Bay,china: reanalysis and standardization

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Acta Oceanologica Sinica 2021年第7期40卷 198-248页

作者： Jianfen Li Zhiwen Shang Fu Wang Yongsheng Chen Lizhu Tian Xingyu Jiang Qian Yu Hong Wang Tianjin center China Geological SurveyTianjin 300170China Key Laboratory of Coast Geo-Environment China Geological SurveyTianjin 300170China Key Laboratory for Coast and Island Development(Nanjing University) Ministry of EducationNanjing 210023China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China

Using 110 newly revised Holocene sea level indicators categorized into three types,sediments(67),shelly cheniers(27)and oyster reefs(16),this paper firstly provides a Holocene relative sea level curve,based on multiple approaches of litho-and biostratigraphies and sedimentary faces analysis,for the west coast of Bohai Bay,*** considerations,including indicative meaning,the paleo tidal pattern and range and conversion from mean tidal level to mean sea level,an apparent relative mean sea level(RMSL)curve was further *** systematical calibration using CALIB,those of the 48 reworked samples were further corrected for the residence-time ***,the younger ages for another 35 samples were chosen at the subsample *** result in a younger-oriented shift for about 0.5 *** local spatial factors,including neotectonic subsidence(average rate about 0.1 mm/a),self-compaction of unconsolidated sediments(between a few decimeters to about 6 m)and subsidence due to groundwater withdrawal(between a few centimeters to about 2.5 m),were quantitatively ***,the amended RMSL curve after eliminating all these local temporo-spatial factors is very likely to show non-existence of mid-Holocene highstand and imply potential influences of both ice-volume equivalent sea level and regional glacial isostatic *** it is still unable to divide both global and regional factors,the slowdown of sea level rise,in 7.5–6.8 ka with a maximum height less than+1 m,may constrain the model effort in the near future.

关键词： cheniers oyster reefs sediments temporospatial corrections local RMSL

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The Type and Evolution of Neoproterozoic Sedimentary Basin in the Dahongshan Region,Northern Margin of the Yangtze Block:An Insight from Sedimentary Characteristics of the Huashan Group

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1917-1918页

作者： DENG Qi WANG Jian CUI Xiaozhuang WANG Zhengjiang SHI Meifeng MA Long Chengdu center China Geological Survey Key Laboratory for Sedimentary Basin and Oil and Gas Resources Ministry of Land and Resources

Objective The Huashan group（composed of the lower Hongshansi Formation and the upper Liufangzui Formation）is an important Neoproterozoic stratigraphic unit along the northern margin of the Yangtze *** documents have focused on the geochronological and geochemical aspects of the Neoproterozoic sedimentary basin in the Dahongshan ***.

关键词： The Type and Evolution of Neoproterozoic Sedimentary Basin in the Dahongshan Region Northern Margin of the Yangtze Block

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Quantitative Analysis of Mineralization-Alteration Index about the Huize Lead-zinc district in Northeast Yunnan, china

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 249-250页

作者： ZHANG Xiaopei HAN Runsheng ZHAO Dong QIU Wenlong HE Jiaojiao CUI Junhao Faculty of land Resource Engineering Kunming University of Science and Technology South-West Institute of geological survey Geological Survey Center for Nonferrous Metals Resources

1 Introduction The super-large Huize lead-zinc ore district is one of the most representative lead-zinc deposits in Northeastern Yunnan poly-metallic deposit concentration *** far,studies(Liu and Lin,1999;Han et al.,2007)on the type of deposits like the Huize lead-zinc deposit,focused on deposit genesis,the sources of metallogenic materials,

关键词： Pb Zn china Quantitative Analysis of Mineralization-Alteration Index about the Huize Lead-zinc district in Northeast Yunnan

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New Insights into the Late Triassic Nadigangri Formation of Northern Qiangtang, Tibet, china： Constraints from U-Pb Ages and Hf Isotopes of Detrital and Magmatic Zircons

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1451-1467页

作者： LI Xueren WANG Jian CHENG Leli FU Xiugen WANG Yuke Chinese Academy of geological Sciences Beijing 100037 China china University of Geosciences (Beijing) Beijing 100083 China Key Laboratory for Sedimentary Basin and Oil and Gas Resources Ministry of Land and Resources Chengdu Sichuan 610081 China Chengdu center of china geological survey Chengdu Sichuan 610081 China Institute of Mud Logging Technology and Engineering Yangtze University Jingzhou Hubei 434023 China

We report here U-Pb age and in situ Hf isotopic results for detrital and magmatic zircons from one conglomerate and four tuffite samples from the Late Triassic Nadigangri Formation across the North Qiangtang depression, Tibet. Coupled with previously published data in the region, this paper proposes new insights into the geochronological framework for the Nadigangri Formation. The deposition ages of tuffite from top to bottom in the Woruo Mountain, Quem Co and Dongqu River, are 203 Ma, 226 Ma, 221.5 Ma and 221.1 Ma, respectively. The detrital zircons yield a younger cluster of ages of 201.5-225 Ma from the conglomerate of the Quem Co Formation. The Late Triassic Nadigangri Formation defines a temporal range approximately between 201 and 225 Ma （Norian-Rhaetian）, including three predominant groups of 220-225 Ma, 210-217 Ma and 201-205 Ma, which correspond with the three main rifting episodes of initial rifting, further rifting and final rifting. Positive ~Hf（t） value and low model ages in younger detrital zircons suggests a juvenile character. However, the Hf isotopes of magmatic zircons display the presence of reworked ancient crust with 1.1-1.8 Ga. These results provide strong constraints not only on the temporal range of the Late Triassic Nadigangri Formation, but also on the onset of the Qiangtang Mesozoic rift basin.

关键词： U-Pb ages Hf isotope Nadigangri Formation Late Triassic Qiangtang

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Remote Sensing Interpretation and Extraction of Structural Information about Active Faults at Hangzhou,china,and Their Surroundings

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Journal of Earth Science 2013年第6期24卷 1056-1067页

作者：张微姚琪陈汉林杨金中 china Aero Geophysical survey & Remote Sensing center for land and Resources china Seismological Bureau Institute of Geology Department of Earth Sciences Zhejiang University

It is important to explore active faults in urban areas and their surroundings for earth- quake disaster mitigation. Satellite remote sensing techniques can play an important role in such active fault exploration. It can not only reveal the pattern of active faults and active tectonics on a macroscop- ic scale, but also monitor the occurrence, development and rules of temporal-spatial evolution of active faults. In this paper, we use the Hangzhou area as an example to introduce methods of extracting de- tailed active fault information when covered by thick unconsolidated Quaternary sediment, using im- age enhancement and image fusion etc. to improve the definition and precision of satellite images and presenting a three-dimensional （3D） image to illustrate tectono-geomorphic features along the relevant faults. We have also collected aeromagnetic anomaly data, shallow seismic exploration data and dating data, and carried out field surveys to validate the characteristics of active faults based on remote sens- ing images. The results revealed about the faults showed a high consistency with traditional geological knowledge, and demonstrate that it is feasible to explore active faults in a weakly active tectonic area by using satellite remote sensing techniques and contribute to large engineering projects and research on neotectonics.

关键词： remote sensing active faults exploration Quaternary image fusion Hangzhou Neotec-tonics.

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