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The Background Features and Formation of Chemical Elements of Groundwater in the Region of the Middle and Lower Reaches of the Yangtze River

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Acta Geologica Sinica(English Edition) 1997年第1期71卷 80-89页

作者： Zeng Zhaohua institute of Environmental geology,Jiangxi Bureau of geology and mineral resources, Nanchang, Jiangxi Shang Ruoyun institute of Environmental geology Jiangxi Bureau of Geology and Mineral Resources Nanchang Jiangxi [?]Zeng Zhaohua Born in 1934. Graduated from Changchun College of geology in 1959. Specialty: hydrogeology and engineering geology. Engaged in studies of hydrogeology engineering geology environmental geology and medical geology. Now the general engineer at the Institute of Environmental Geology Jiangxi Bureau of Geology and Mineral Resources.

The paper deals with the background features, formation and distribution of the chemical el-ements K, Na, Ca, Mg, Si, Fe, Mn, Cr, Ni,V, Co, Ti, Mo, Cu, Pb, Zn, As, Hg, Cd, Be, Li, Sr, B,F, Cl, Br and I in the groundwater in the region of the middle and lower reaches of the YangtzeRiver and their relations to the composition of the water-bearing media, properties of the overly-ing rocks and soils, redox environment, and groundwater flow condition, mineralization and pHof groundwater.

关键词： lower-middle reaches of the Yangtze River groundwater chemical element background feature

Identification of Hercynian shoshonitic intrusive rocks in central Hainan Island and its geotectonic implications

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Science Bulletin 2006年第20期51卷 2507-2519页

作者： XIE Caifu1, 2, ZHU Jinchu1, DING Shijiang3, ZHANG Yeming2, FU Tai’an2 & LI Zhihong2 1. State Key Laboratory for mineral Deposits Research and Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2. Yichang institute of geology and mineral resources, Yichang 443003, China 3. Hainan Bureau of geology and mineral resources, Haikou 570226, China State Key Laboratory for mineral Deposits Research and Department of Earth Sciences Nanjing University Nanjing China Yichang institute of geology and mineral resources Yichang China Hainan Bureau of geology and mineral resources Haikou China

An identification has been made of some shoshonitic intrusive rocks in central Hainan Island recently. These rocks are K-rich (K2O=2.9%―5.1%, K2O/Na2O=0.95―2.12), distinctly enriched in LILE and LREE, strongly depleted in Nb, Ta, and moder- ately depleted in Sr and Ti, with (87Sr/86Sr)i = 0.70859―0.71425 and ε Nd(t) = (?2.77―?7.49). They were derived from an EMⅡ-type mantle source. The enrichment process is related to metasomatism of depleted mantle caused by a great amount of fluid-melt released from oceanic crust and terri- genous sediments at great depth (eclogite facies) during the subduction of the South China plate under the Indochina-South China Sea plate in the Carbon- iferous–Early Permian. A SHRIMP U-Pb zircon dating yields a crystallization age of 272±7 Ma for the sho- shonitic intrusions, which is coeval with the strongly peraluminous granites found in central Hainan Island. These two kinds of rocks generally possess syn-intrusion ductile deformation structures. Thus they are considered to have been generated during the early stage (syn-thrust phase) of a post-collisional event. The primary magma of shoshonitic rocks was produced at a depth > 80 km by decompression- dehydration melting of previously enriched litho- spheric mantle wedge, phlogopite-bearing garnet peridotite, which was in turn caused by the break-off of a descendent slab and upwelling of a hot as- thenosphere. The rising of melts was accompaniedby crustal contamination and crystallization fractiona- tion (AFC). Combining with other related data, it is proposed that the southwards subduction and amal- gamation of the South China plate with the Indo- China-South China Sea plate took place at ca. 287- 278 Ma, which was a part of the convergence proc- ess of the Pangea supercontinent. The suture zone was probably located along the line of Song Ma-Beibu Gulf-north margin of the Yunkai Moun- tains-Wuyi Mountains.

关键词： SHRIMP U-Pb dating Hercynian shoshonitic intrusive rocks post-collisional event enriched mantle Hainan Island.

Early Ordovician Sea Level Changes in South China and Their Worldwide Correlation

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Journal of Earth Science 1996年第1期15卷 54-62页

作者： Wang Xiaofeng (Yichang institute of geology and mineral resources, CAGS, Yichang 443003) Li Zhiming Chen Jianqiang (Department of geology and mineral resources, China University of Geosciences, Beijing 100083) Chen Xiaohong (Yichang institute of geology a

The sea level changes and their correlation from the latest Cambrian C. proavus zone to the Ordovician N. gracilis zone in South China are discussed on the basis of the Ordovician paleogeographic reconstruction in China. The study of sequence, biostratigraphy and ecostratigraphy suggests that at least 8 major regressive events, occurring in the following levels: basal H. simplex zone (RE1), near the base of C. intermedius zone (RE2), basal C. angulatus zone (RE3), near Mid/Upper G. quadriplicatus zone (RE4) and succeeding the first phase (RE4a) of RE4 at basal P. deltifer zone, Kiaerograptus/Brygograptus zonal boundary (RE5), end *** A. Z.(RE6), end P. originalis zone (RE7) and Early H. teretiusculus or end P. serra zone (RE8), can be recognized in the cratonic plat- form and its shelf-slope tracts of the South China plate based on sequence change or disconformity and associated breaks in biological succession. Most of them can be traced in the other plates or continents.

关键词： Ordovician sea level change sequence.

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辽西义县组孢粉植物群指示的古气候条件

微体古生物学报 2004年第3期21卷 332-341页

作者：丁秋红张立东沈阳地质矿产研究所沈阳110033

迄今为止 ,在辽西北票义县地区的下白垩统义县组二段沉积层中 ,已发现孢粉化石 6 2属 ,82种 ,藻类化石 3种。本文对产于不同地点沉积层中的孢粉化石进行了系统研究和总结。根据孢粉母体植物形态和生态特征、生长的气候环境和干湿度环境 ... 详细信息

迄今为止 ,在辽西北票义县地区的下白垩统义县组二段沉积层中 ,已发现孢粉化石 6 2属 ,82种 ,藻类化石 3种。本文对产于不同地点沉积层中的孢粉化石进行了系统研究和总结。根据孢粉母体植物形态和生态特征、生长的气候环境和干湿度环境 ,对义县组二段的孢粉植物群进行了植被类型、气候带类型和干湿度类型的统计和划分 ,认为义县组二段沉积时期 ,其孢粉植被类型为针叶林 ,所处的气候环境为湿润的亚热带—暖温带。由于植被成分中存在落叶阔叶植物和旱生植物 ,推测气候环境存在季节性变化 ,间有干旱—半干旱气候条件。

关键词：孢粉植物群古气候早白垩世义县组辽宁地层发育

DIVISION and CORRELATION OF MIDDLE—UPPER PROTEROZOIC IN WESTERN SECTION OF MIDDLE QILIANSHAN

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甘肃地质 1985年第S1期 161-162页

作者： institute of geology Bureau of geology and mineral resources of Gansu

Qilianshan is the important mountain in Northwestern China,where theUpper Precambrian is well developed,in which especially in the westernsection of middle Qilianshan is extensive distributed,where the Upper Pre-cambrian succession iS complete in comparison,this is the important areafor researching into a geosyclinal type deposit of Middle—Late Proterozoicera.

关键词： UPPER PROTEROZOIC IN WESTERN SECTION OF MIDDLE QILIANSHAN DIVISION and CORRELATION OF MIDDLE

mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang institute of mineral Deposits, Chinese Academy of Geological Sciences, Beijing Geological Party No.3, Hebei Bureau of geology and mineral resources, Zhang jiakou, Hebei Fei Zhenbi institute of mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2Te. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： mineralogy and Mode of Occurrence of Gold Hebei Province

DIVISION OF CARBONIFEROUS COAL-ACCUMULATING AGES, REGIONS AND ZONES IN NORTH CHINA

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Chinese Science Bulletin 1989年第13期34卷 1110-1115页

作者：张志存 Yichang institute of geology and mineral resources MGMR

During the middle-late Carboniferous, the Yumengou Group, a series of the paralic coal-bearing deposits, was formed in North China gigantic subsidence between the Yinshan and the Qinling gigantic latitudinal tectonic zones. In the Yumengou Group the coal-forming actions occurred many times, in which the coal-accumulating actions forming industrial high seams repeatedly occurred, too.

关键词： North China Carboniferous coal-accumulating age coal-accumulating region coal-accumulating zone

ON THE UPPER PRECAMBRIAN IN SOUTHERN LIAODOING PENINSULA

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ON THE UPPER PRECAMBRIAN IN SOUTHERN LIAODOING PENINSULA

Hydrogen and Oxygen Isotope Study on the Water-Rock Interaction of the Yinshan (Cu-) Pb-Zn-Ag Ore Deposit, Jiangxi Province

作者： Research Group Upper Precambrian (shenyang institute of geology and mineral resources,Chinese Academy of Geological Sciences)

＜正＞The southern Liaodong Peninsula,well-known for its Late Precambrian strata which are characterized by wide distribution,relatively complete sequence,huge thickness,distinct upper and lower limits,and rich fossils,is one of the important regions for the study of the Late Precambrian strata in China and critical area to link up the two different Late Precambrian stratotypes in both South China and North China into one complete sequence of Upper Precambrian Series in China.

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Acta Geologica Sinica(English Edition) 1996年第3期70卷 274-289页

作者： Zhang Ligang, Liu Jingxiu, Yu Guixiang and Chen Zhensheng Yichang institute of geology and mineral resources, CAGS, Yichang, Hubei Jiang Minxi Y ichang institute of geology and mineral resources CAGS Yichang Hubei

The δ18O values of vein quartz of different stages from the Yinshan ore deposit are constant around 16‰ and the calculated δ18OH2O values attain 8‰± ; the δDH2O values of fluid inclu-sions in vein quartz are constant at about-60‰. From the surface down to 1200 m below the δ18O values of altered rocks gradually decrease from 15‰± to 11‰± . Various water-rock inversion calculations indicate that the ore fluids were formed by the interaction between meteoric water and phyllite at 350℃ and the effective W/ R value of around 0.1. When the water-rock exchange in the upper mineralization system took place, the effective W / R value increased to 5.0 or more. As a result, an evolution and mineralization model of a buffered open system with two-stage water-rock interactions is proposed in this study.

关键词： H and O isotopes water-rock exchange buffered open system Yinshan of Jiangxi Province