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The Status of Organochlorine Pesticides Pollution in Hubei Section of the Yangtze River

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地学前缘 2009年第S1期16卷 81-82页

作者： Chen Liu,Liyuan Guo School of the Earth sciences and Resources,china University of Geosciences(beijing),beijing 100083,china.

The Organochlorine Pesticides(OCPs),such as hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloro ethane(DDT),are well known as typical persistent organic pollutions(POPs).They were worldwide used several decades ago,even today in some *** the water resource is very important in natural environments and essential to agriculture,the pollution of OCPs in water has emerged as worldwide environmental problem. Wuhan section of the Yangtze River is the drinking water source of Wuhan area in Hubei *** addition,Hubei province is an important production base of grain,cotton,oil and *** the rapid development of industry and mass-use of OCPs

关键词： organochlorine pesticides Yangtze River water residues

GRANITOIDS,VOLCANIC ROCKS AND CHERTS FROM NORTH ALTYN TAGH,NW china: IMPLICATION FOR THE TECTONIC ENVIRONMENT DISCRIMINATION

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地学前缘 2000年第S1期7卷 249-250页

作者： Chen Xuanhua\+1,Wang Xiaofeng\+1,Chen Zhengle\+1,George Gehrels\+2.Yin An\+3[WT5,5”BX](1.institute of Geomechanics,CAGS,beijing 100081,{2. 2.Department of Geosciences, University of Arizona,Tucson,AZ 8572.,USA 3.Department of Earth and Space Science

Granitoids,volcanic rocks and cherts,mainly of early Paleozoic,in northern Altyn Tagh(Fig.1) are analyzed here for the purpose of the determination of the tectonic environments and their development since Early Paleozoic.(1) Granitoids\ The collection of 12. main\|element petrochemical data from North Altyn Tagh area shows that most of the granitoids here are granites and granodiorites of calc\|alkaline *** consist mainly of metaluminous and peraluminous in Shand’s index,and only one of them,which belongs to Mesozoic,is *** of the granitoids plot in the IAG+CAG+CCG fields in the Maniar and Piccoli’s diagrams (1989) for tectonic discrimination of *** (Island arc granitoids)and CAG (Continental arc granitoids) can be distinguished for Early and Late Paleozoic granitoids,and maybe some CCG (Continental collision granitoids) for Early *** of Mesozoic and Cenozoic inherited the characteristics of those of *** active plate margin (pre\|plate collision)and Anatectic magmatism(syn\|orogenic,S\|type granites)are distinguished (Fig.2.for Paleozoic granitoids using de la Roche R 1\| R 2.multicationic diagram (Batchelor and Bowden,1985).Mesozoic and Cenozoic granitoids inherited the characteristics of Anatectic magmatism (syn\|orogenic)of these early ones,and post\|orogenic(A\|type)granites occurred in *** mechanism for magma formation is mainly partial melting.

关键词： granitoids volcanic rocks cherts tectonic environ ment Altyn Tagh

TECC Applied in Geopark for a Case Study of Qixia Planning National Geopark

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地学前缘 2009年第S1期16卷 295-296页

作者： Feifei Hu,Mingzhong Tian School of the Earth sciences and Resources,china University of Geosciences(beijing),beijing 100083,china.

This paper applied the theory of TECC(Tourism Environmental Carrying Capacity) into the case of Qixia Planning National *** adopt new planning framework to do the planning of TECC。

关键词： TECC geoheritages basic environment Qixia Planning National Geopark

Clay Minerals of the Middle Jurassic Through Lower Cretaceous in Guangyuan Area,Northern Sichuan:Implications to Paleoclimate

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地学前缘 2009年第S1期16卷 111-111页

作者： Ke Cao~1,Xianghui Li~2.1.School of Earth sciences and Resources,china University of Geosciences(beijing),beijing 100083,china. 2.Nanjing University,Nanjing 2.0093,china

Clay mineral analyses of the Middle Jurassic through the Early Cretaceous sedimentary rocks from the Guangyuan-Jian’ge section,Sichuan Basin (southwestern china)were undertaken in this article, which is aiming to reconstruct the palaeoclimate of the *** contents of the four clay minerals, smectite(2..8%-1.0%-46.8%),kaolinite(31.0%- 12.5%-12.6%),illite(31.3%-68.0%-2..0%)and chlorite(11.8%-8.5%-12.6%),as the target clay minerals,illite crystalline index(0.2.-0.31-0.2.)and chemical index(0.62.0.66-0.79)are used as indicator of *** is indicated that changes of

关键词： Middle Jurassic-Early Cretaceous clay mineral climate Sichuan Basin

PRELIMINARY STUDY OF GEOLOGY AND GEOMORPHOLOGY OF LUONAN BASIN

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地学前缘 2000年第S1期7卷 332-332页

作者： Zhou Houyun 1, Han Mukang 2. Hou Jianjun 3[WT5,5”BX](1 Guangzhou institute of Geochemistry, the chinese {2. of Science, Guangzhou 510640, china 2.Department of Urban and Environmental sciences, Peking University, beijing 100871, china 3 Dep

Luonan Basin, formed during Neo\|tectonic movements, is one of the small block basins in East Qinling Mountain. Three faults, Tieluzi Fault, Dajing\|Guojiayuan Fault and Beisi Fault bound it. The west part of the basin is higher than the east part. The elevation, usually more than 1100meters in the west, decreases gradually to less than 800meters in the east. The Cenozoic deposit in Luonan Basin is thin in the west part and becomes increasingly thick towards the east part. The total thickness of both the Eogene and the Neogene is only more than 100meters at Dajing. At Duishan, a place close to Luonan county town, it is about 400meters, and at Gucheng, it becomes nearly 1750meters. The strata crop out in the west part of the basin, usually the Eogene and the Neogene, are older than those in the east part which are usually the Quaternary deposits. The pattern of the Cenozoic deposits in Luonan Basin is similar to that in Shangzhou Basin (Li Kaoshe, personal communication), a basin locating just to the south of Luonan Basin.

关键词： East Qinling Mountain Luonan basin topography Cenozoic deposits structural landforms Tieluzi fault eastwards movement

Identification of Sources of Potential Fields with Directional Wavelet Transform:Application to Mineral Exploration

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地学前缘 2009年第S1期16卷 146-146页

作者： Dianhua Cao,Anjian Wang institute of Mineral Resources,chinese {2. of Geological sciences,beijing 100037,china.

For the sustainable supply of mineral resources, blind deposits are becoming the emphasis of exploration after long-period exploitation of exposed *** collection and analysis of gravity or magnetic data represents one of the cheapest forms of large-scale geophysical *** the identification of potential fields,we can get the map of worms or skeletonizations showing the three-dimension structure of shallow crust,and find the

关键词： potential field directional wavelet transform multidirectional and multiscale edges detection mineral exploration

CENOZOIC FAULTING ALONG THE SOUTHEASTERN EDGE OF THE TIBETAN PLATEAU IN THE YANYUAN AREA AND ITS TECTONIC IMPLICATIONS

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地学前缘 2000年第S1期7卷 269-269页

作者： Wang Erchie 1, Burchfiel B. Clark 2.WT5,5”BX](1 institute of Geology and Geophysics, {2. academy of Science,beijing 10002.,china 2.Department of Earth, Atmospheric and Planetary sciences, MIT,Cambridge, MA 02.39,UK)

The southeastern edge of the Tibetan plateau is marked by several thrust sheets trending roughly in E\|W direction. The Yanyuan thrust sheet is bounded by three arcuate thrust belts, marked by high mountain ranges with the Jinhe belt on the north, the Qianhe belt on the south and the Ninglang belt on the west. Within the Yanyuan thrust belt are sedimentary cover rocks of the Yangtze platform, with ages ranging from Sinian to Triassic. In the north, the thrust sheet is overlain by the Muli thrust sheet along the Jinhe belt, while in the south, it is underlain by the Kangdian paleoland along the Qianhe belt. The youngest rocks on the foot wall are late Eocene to Oligocene in age, indicating that the thrusting occurred in the late Tertiary. The top of the Yanyuan thrust belt is truncated by a flat erosion surface similar to that on the plateau to the north. Along a north\|dipping normal fault bordering the Yanyuan basin on the south, the erosion surface is tilted to the south against Triassic rocks. The basin is filled with coal\|bearing clastic sediments of Pliocene and early Pleistocene age, which gives the timing of the normal faulting. Based on the faulting pattern, we propose that the southeastern edge of the Tibetan plateau underwent a large amount of N\|S shortening and uplift along the Yanyuan thrust sheet in the late Tertiary, while the subsequent normal faulting that had occurred along the Yanyuan basin during the Pliocene and Pliocene can be interpreted to have accommodated gravitational collapse of the crust.

关键词： southeastern edge of the Tibetan plateau Yanyuan thrust shee t crustal shortening and uplift normal faulting gravitational collapse

Study on Velocity Structure Models of the Sub-Sediments in Zhapu and Jintang near the Hangzhou Bay

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地学前缘 2009年第S1期16卷 227-227页

作者： Xianming Deng~(1,2.,Chunhui Tao~1,Chunyan Sun~2.Jianping Zhou~1,Chunhua Gu~1 1.Key laboratory of Submarine Geo{2.,The Second institute of Oceanography,SOA,Hangzhou 310012.china. 2.china University of Geo{2.(beijing),beijing 100083,china

Marine sediment velocity structural models have strong regional *** made two shallow continental shelf sediment velocity structure models,Lu Bo gave a model in accordance with the characteristics of the continental shelf of ***,no model can contain all geological *** got the in-situ velocity data at Zhapu and Jintang near the Hangzhou Bay by using the MFI GeoA(Multi-Frequency In-situ Geoacoustic Measurement),and used these data to make the velocity structure ***,we got two different *** is Zhapu velocity structural model that we can describe as Lower velocity-Higher velocity -Lower velocity-Higher velocity model simply。

关键词： sub-sediments velocity structure models in-situ measurement Zhapu and Jintang

THE GEOCHEMISTRY CHARACTERISTICS OF BLUESCHIST IN THE GANGMAR AREA, QIANGTANG BLOCK, TIBET

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地学前缘 2000年第S1期7卷 191-191页

作者： Deng Xiguang 1, Ding Lin 1, Liu Xiaohan 1,An Yin 2. Paul A.Kapp 2. Michael A.Murphy 2. Craig E.Manning 2.WT5,5”BX](1 institute of Geology and Geophysics, {2., P.O.Box 982., beijing 10002.,china 2.Department of Earth an

The Qinghai—Xizang (Tibet) Plateau was assembled by the successive accretion of continental and arc terranes to Asia during the Palaeozoic, Mesozoic and early Tertiary. From north to south, the Plateau was divided into four terranes (from north to south): Songpan\|Garze, Qingtang, Lhasa and India terranes. The Qiangtang terrane was divided into two parts by Chabu\|Shuanghu suture: Northern Qiangtang and Southern Qiangtang blocks. It was believed that there is a suture as Palaeotethyan suture between the two blocks from Lungmu lake to Chabu, to Shuanghu, to Langcangjiang, but some geologists opposited this opinion, such as Wang Chengshan et al.(1987) and Deng Wanming et al.(1996). The blueschists that bear the typical glaucophane were found in the Gangmar Area in summer of 1997. The blueschists consist of glaucophane, crossite, phengite, actinolite, epidote, sphene ,rutile, and so on. Blueschists show nappe structures in enclosing rocks, and thrust over Tertiary from north to *** age of blueschist is 2.5～2.5Ma which stand for the metamorphic age of blueschist. The geochemical contents of blueschists are the following: SiO\-2.is 45 37%～53 82., Na 2.>K 2., K 2.+Na 2. are 3 72.～7 61%, Na 2./K 2. is 1 70～19 67, MnO is 0 16%～0 2.%, FeO+Fe 2. 3 are 11 12.～14 2.%, TiO 2.is 2.34%～4 2.%, P 2. 5 is 0 34%～1 03%. From the contents, SiO 2.is inverse relation with K 2.+Na 2., K 2. and FeO+Fe 2. 3. In the SiO 2.|K 2.+Na 2. diagram, the blueschists fall in the field of Alkali basalt; in the TiO 2.|MnO(10\|P 2. 5×10 triangular diagram, these plot within the Ocean Island Basalts(OIB) field. The whole REE content is (117 03～390 97)×10 -6 , LREE/HREE is 5 05～9 80, the REE diagram shows the feature that LREE is rich and HREE is depleted, this is similar to the OIB. In the spidergram of trace elements show the same characterristics as the OIB. Meanwhile, the trace elements ratios, such as Ba/Nb, La/Nb, Nb/Th, Nb/Y, Zr/Y, Zr/Nb, Hf/Sm, Ta/Hf, Nb/Ta, Nb/U, suggest the tectonic setting

关键词： Geochemistry Characteristics Ocean Island Basalt Paleo\|T ethyan Suture Blueschist Gangmar Area Tibet