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1.
1IntroductionPhosphorus,an essential nutrient for the primaryproductivity in freshwater systems,is an important fac-tor controlling lacustrine eutrophication.Although ex-ternal input of phosphorus has been assumed as the vi-tal responsibility for the eutrophication of lakes(ZhuJun et al.,2005),the remobilization of phosphorus insediments has a distinct influence on it as well(Bostr m et al.,1982).The concentrations of totalphosphorus(Ptotal)in the sediments are often related tothe trophic st…  相似文献   

2.
INTRODUCTIONFresh water lakes are one of the planet’s mosti mportant freshwater resources.They support life invarious forms,develop tourism and provide uniquerecreational opportunities.It is also a good source ofthe provision of drinking-water for local communi-ties.Studies on trace elements in rivers,lakes,andsedi ments(Zhou et al.,2004;Gray et al.,2000;Grosheva et al.,2000;Klavins et al.,2000;Aucoinet al.,1999;Bortoli et al.,1998;Elbaz-Poulichet etal.,1996;Johansson et al.,1995;F r…  相似文献   

3.
正1 Introduction There are numerous salt lakes in western China(Zheng Mianping,et al.,2011).Yiliping playa on the western Qaidam Basin is a magnesium sulfate subtype dry salt lake with high concentrations of potassium,boron and lithium.  相似文献   

4.
The Gandise massif in Tibet, China, is one of the most important copper-multimetal metallogenic belt of Tibet region( Hou, et al,2001 ; Qu, et al, 2001 ;  相似文献   

5.
The Zaibian mafic-ultramafic rock is located in the transitional zone of the Yangtze craton and south China fold system, where is the southwest of Jiangnan orogenic belt (Zeng et al. , 2003 ; Wang et al. ,in press).  相似文献   

6.
1. Introduction Tongling district is situated in the southern part of the Yangtze River, Anhui province, China (Fig. 1). It is one of the most important metal basements in China, being rich copper material resources, also named "ancient copper capital of China". Studies showed that each copper ore deposit is bound up with the intermediate-acid intrusive rocks in the area. Therefore, many researchers (e.g. Chang Yinfu et al, 1987; Xing Fengming, et al, 1995; Zhou Xinrou, et al, 1993; and…  相似文献   

7.
<正>1 Introduction Wufeng-Longmaxi organic-rich shale in the Late Ordovician-Early Silurian is widely distributed in South China(Qiu et al.,2013),which is also the target formations of shale gas industry.Until now,the investigations into shale gas reservoirs is mainly conducted in eastern and southern part of Sichuan Basin(Huang et al.,2012;Liu et  相似文献   

8.
INTRODUCTIONYingen-Ejinaqi basinis locatedin the WulatehouBanner in the west of the Inner Mongolia Autono-mous Region of China ,and covers an area of approxi-mately 122 000 km2( Chen et al ., 2001) . As aMesozoic-Cenozoic depression in Yingen-Ejinaqi ba-sin,the Chagan depression lies in the northeast ofthis basin (Fig.1) .It is about 60 kmlong and 34 kmwide and covers an area of approxi mately 2 000 km2( Wang et al .,2002) .In terms of the basement ter-rain,forms of major structural…  相似文献   

9.
1 Introduction The Jiufotang Formation is one of the most fossil- productive Early Cretaceous deposits of China. It overlies the famous Yixian Formation from which many important taxa were found (Ji et al., 2004; Chang et al., 2003; Zhou et al., 2003). In addition to other vertebrates, pterosaurs, the first flying reptiles in Earth history, are also abundant in the Jiufotang Formation. At present, nine species belonging to five genera have been reported from the Jiufotang Formation. The…  相似文献   

10.
1 Introduction The Gaojiacun intrusive complex is one of the numerous ultramafic-mafic intrusions in Sichuan Province of China. It was mapped during the 1970s and studied mainly by Chinese scientists (e.g. Geological Team 106, 1975; Shen et al., 1986, 1989; CGGJC, 1986; Yang et al., 1993; Li et al., 1995; Shen et al., 2003; Zhu et al., 2004a). Since the year 2000, China has become one of the largest PGE consumers. While the country can produce only less than 1 ton PGE/year, the Chin…  相似文献   

11.
<正>1 Introduction The exploration and development of unconventional oil and gas is gradually becoming the new hot topic,which is promoted by the increasing demand of oil and gas,as well as the decline in conventional oil and gas production(Jia et al.,2012;Zou et al.,2012).The researches of unconventional oil and gas resources started late in China,while the resources are widely distributed,including  相似文献   

12.
INTRODUCTIONThe anchorage of geomaterial , including shaftanchors and prestressed tendons ,is usually used ingeotechnical engineering. Owing to various advanta-ges ,these two anchorage types are widely used instructures in China ( Cao et al ., 2003 ; Fu et al .,1999 ;Lu et al .,1998 ; Li et al .,1995) . Shaft an-chors can be classifiedinto three kinds by the forceinthe shaft and cement grout :tensile ,press ,and sheartype (Lu et al .,1998) . The tensile type is the mostpopular in China…  相似文献   

13.
1. IntroductionThe Mianlue (Mianxian-Lueyang) suture zone is one of the components of the Qinling orogenic belt and the latest major suture zone between North and South China. The data available suggest that it is a complicated ophiolitic tectonic melange zone including many tectonic slabs of different origins (Zhang et al., 1995; Lai et al., 1996; Lai et al.,1997; Lai et al.,1998; Xu et al.,1996). Up to now, however, there is not definite evidence of volcanic rock assemblage and geochemi…  相似文献   

14.
1. Introduction The depth of source of Cenozoic basalts and the genesis of mantle xenoliths in eastern China have been widely discussed by many geoscientists. There were basically two main opinions: one was that the relationship of basalts and the peridotite xenoliths are melt and residues (Cong et al, 1982; Liu et al, 1985; Qiu et al, 1986; E et al, 1987; Chi et al, 1988; Deng et al, 1988), and pyroxenite and gabrro enclaves are accumulation of fractional crystallization (Qiu et al, 1986;…  相似文献   

15.
正Objective The Khondalite Belt is a nearly E–W-trending Paleoproterozoic Himalayan-type orogen in the Western Block of the North China Craton. It is regarded as a result of the collision between the northern Yinshan Block and the southern Ordos Block at ~1.95 Ga, which led to the formation of the united basement of the Western Block(e.g., Zhao et al., 2005; Yin et al., 2011). The Khondalite Belt has undergone long-term continent-continen collisional orogenic processes, and a remarkable series of late-stage orogen-parallel ductile shear zones developed(e.g., Huang et al., 2013; Gong et al., 2014).  相似文献   

16.
1 Introduction The North China Craton (NCC) is considered to be the oldest and largest cratonic block in China. Recent studies to gain understanding of basement architecture of the NCC has led to its division into the Western and Eastern Blocks, separated by a N-S trending Paleoproterozoic Trans-North China Orogen (TNCO) (Fig. 1; Zhao et al., 1998, 1999a, 2000a, 2001a; Wilde et al., 2002). Although there is now abroad consensus that the final assembly of the NCC was completed by th…  相似文献   

17.
正Objective The Tibetan Plateau, located in the eastern part of the Alpine Himalayan tectonic domain, is the youngest and the most spectacular of all continent-continent collisional belts in the world(Zhang et al., 2007; Xu et al., 2011; Zhu et al., 2012).  相似文献   

18.
<正>1 Introduction Daxinganling region is one of the most important nonferrous metal metallogenetic province(Wu et al.,2011;Li et al.,2014).The northern Daxinganling was a geological blank area in China formerly(Li et al.,2017).However,the region has a huge resource potential.Forty metal deposits have been found in the area recently,with  相似文献   

19.
正Objective Indosinian magmatic rocks mainly locate in west Qinling Orogen,which are,however,extremely rare in east Qingling Orogen(Lu Xinxiang,2000;Zhang Guowei et al.,2001;Guo Xianqing et al.,2017).The ZhifangHuangzhuang(ZH)area in south Songxian County is located in the southern margin of the North China Craton  相似文献   

20.
<正>In summary,field observations and detailed measurements suggest that the red-ribbon style iron-ore bodies in Xinyu iron deposit result from regional plastic flow and sausage bending,rather than fold superimposition.The Xinyu iron deposit,located in central Jiangxi Province,is one of the most important BIF-type deposits in China.It is hosted in the Late Proterozoic volcanicsedimentary rocks,which are composed of sericitechlorite pyhllite,magnetite-bearing chlorite phyllite or schist,magnetite quartzite,and schist(Yu et al.,1989;Zeng et al.,2011).The Xinyu iron orefield lies on the eastern side of the Wugong Shan uplift,to the north of the South China  相似文献   

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