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Li M.,China Geological Survey | Li M.,Chinese Academy of Geological Sciences | Xi X.,China Geological Survey | Xiao G.,China Geological Survey | And 5 more authors.
Journal of Geochemical Exploration | Year: 2014

Since 1999, a new geochemical mapping project, the National Multi-Purpose Regional Geochemical Survey (NMPRGS), has been carried out in the agriculturally and industrially developed regions of China, covering mainly the plains of the eastern and central parts of the country. The primary purpose of this project is to generate systematic multi-medium geochemical data that can be used by subject-matter experts to support the development of policies for protecting the surface environment, improving the efficiency of agriculture and supporting land use planning. Surface (0-20cm) soils were collected at a density of 1 sample/km2 and deep soils (150-180cm) were taken at a density of 1 sample/4km2. Samples from 4km2 for surface soils, 16km2 for deep soils, were composited for chemical analysis. Additionally, lake sediments and near-shore sediments were collected at a lower density. Each sample was analyzed for total content of 52 components (Ag, As, Au, B, Ba, Be, Bi, Br, Cd, Ce, Cl, Co, Cr, Cu, F, Ga, Ge, Hg, I, La, Li, Mn, Mo, N, Nb, Ni, P, Pb, Rb, S, Sb, Sc, Se, Sn, Sr, Th, Ti, Tl, U, V, W, Y, Zn, Zr, SiO2, Al2O3, TFe2O3, MgO, CaO, Na2O, K2O and total carbon), organic carbon and pH. As of the end of 2012, sampling of 1.7millionkm2 has been completed and samples from 1.5millionkm2 have been analyzed. Preliminary achievements have been made in the studies of geochemical variations, the establishment of the natural background and eco-geochemical assessment. An encouraging progress has been made in the application of geochemical knowledge to protecting the surface environment, improving the efficiency of agriculture and promoting sustainable land use. © 2013. Source

Ye Y.-Q.,Hubei Engineering University | Wen H.,Sichuan Institute of Geological Survey | Zuo Z.-J.,Hubei Engineering University
Geology in China | Year: 2013

Covering the metahogenic geological background, metallogenic regularity, prediction of mineral resources, gravity, magnetic, geochemical exploration, remote sensing, natural placer and other professional fields, The special research op China's mineral resources potential evaluation has gained huge amounts of achievements, and the amount of data has attained TB grade. The research and implementation of the integrated-database model of China's mineral resource potential evaluation, which integrates and utilizes the national basic data resource, constitute a very challenging task. The integrated-database model is foundation of building the mineral resource potential evaluation technology platform. The model aims to integrate the basic data and the high application, and also to link together the provincial, regional, national levels as well as maintain the proper functioning of the mineral resource potential evaluation at different scales. This paper systematically describes the integrated-database model of China's mineral resource potential evaluation and its concrete realization. This study has important practical significance and can play a guiding role in the national basic data resource construction. Source

Mao X.,China University of Geosciences | Yin F.,Chengdu Institute of Geology and Mineral Resources | Tang Y.,Chengdu Institute of Geology and Mineral Resources | Wang D.,Chengdu Institute of Geology and Mineral Resources | And 2 more authors.
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | Year: 2014

On the western margin of the Baoshan block, a set of tectonic mélange can be seen along the western Lushui-Luxi tectonic zone. It is characterized by matrices consisting of strongly deformed and low-grade metamorphic clastic rocks bearing graptolite of Sinian-Paleozoic Pumanshao Group and Gongyanghe Group and volcanic flysch turbidite, and structural lens consisting of siliceous, graywacke, part limestone, conglomerate, basalt and granite. The ages of these rocks range from Sinian to Paleozoic and get younger from east to west, which shows the characters of retrogressive accretion. In the early stage, the structural styles are characterized by imbricate structures formed by thrust faults and homoclinal-overturned folds, and nearly N-S-trending shear in the late stage. The characteristics of basalt-andesite and rhylite are of arc volcanic rocks, and the basalt shows characteristics of continental intraplate volcanic rocks. Both of the two types of volcanic rocks maybe account for the tectonic setting of island arc and back-arc extension. Cambrian and Ordovician granite can be divided into the western belt and eastern belt, and the ages of the latter are earlier than that of the former. Those granites are part of magmatic arc of the western margin of the Baoshan block. Therefore, this tectonic mélange records the geological events such as extinction to the subduction of the oceanic crust and magmatic sedimentation-volcanic-magmatic-tectonic events during the formation process of accretionary wedge, and also records the information of the Early Paleozoic accretionary orogenesis on the western margin of the Baoshan block. Meanwhile, it suggests the existence of an ocean basin during Sinian-Paleozoic in the Lushui-Luxi tectonic zone. Source

Yin F.-G.,Chengdu Center | Zhang H.,Yunnan Institute of Geological Survey | Huang Y.,Guizhou Institute of Geological Survey | Ye P.-S.,Chinese Academy of Geological Sciences | And 3 more authors.
Geological Bulletin of China | Year: 2012

The Dali-Ruili railway is an important part of the south line of the Fanya railway. In order to solve the complex geological problems in railway building, China Geological Survey carried out 1:50000 regional geological mapping and environment hazard investigation from January 2008 to December 2010. Six working items were set up, which included twenty-two 1:50000 mapping items and one comprehensive research item. Important progresses were made in such basic geological aspects as structure, petrology, strata and paleontology through systematic regional geological survey. A number of high-precision age data were obtained. The Baoshan block is considered to be a part of the Gondwana continent. Luxi tectonic melange belt was discovered, which is thought to be a part of the Nujiang tectonic melange belt. Source

Peng D.,Bureau of Mineral Resources | Lin L.,Chengdu University of Technology | Wang Q.-W.,Sichuan Institute of Geological Survey | Kan Z.-Z.,Sichuan Institute of Geological Survey | And 2 more authors.
Geology in China | Year: 2011

Manganese nodules were found for the first time near Zhongmula Village of Litang County in Sichuan Province, along the Garze- Litang suture zone. Based on geological mapping and integrated investigation, it is found that the manganese nodules are distributed in the black silt slate of Waneng Mélange belonging to the suture zone, and its sedmentary sequence is basalt→silicite→-black manganese nodules-bearing silt slate. The major chemical compositions of the manganese nodules are characterized by high Mn and low Fe, Si, Ca. The Mn content is 42. 19% which is 1.83 times higher than average Mn content of oceanic nodules; Mn/Fe ratios are relatively high, reaching 8.1. The content of most of the trace elements in the manganese nodules is lower than that of ocean nodules except for Cr whose content is 2-7 times higher than that of ocean ones. Rare elements have distinct Ce positive anomalies, and ΣREE, LREE/HREE, Eu are similar to things of sandstone and siliceous rocks but are very different from things of the basalt. The tectonic environment of the manganese nodules is a continental margin with weak volcanic activity, indicating that sedimentation occurred in an environment of the most strong expansion of the Ganze-Litang Ocean, during which the width of ocean was still limited in comparison with modern oceans. Source

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