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Acta Geologica Sinica(English Edition) 2004年第2期78卷 428-434页

作者： WANGZhiliang MAOJingwen yangjianmin CHENWen ZHANGZuoheng InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037 InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037／／FacultyofGeosciencesandResourcesChinaUniversityofGeosciencesBeijing100083 InstituteofGeology ChineseAcademyofGeologicalSciencesBeijing100037

By using the 40Ar-39Ar chronological method to date K-feldspar from K-feldspar granite in the Qiaohuote copper district, the authors obtained a plateau age of 274.78±0.44 Ma and an isochron age of 272.7±3.0 Ma. Because there is no tectonic deformation overprinted or hydrothermal alteration in the K-feldspar granite intrusion after its emplacement, the 40Ar-39Ar age represents the crystallization age of K-feldspar in K-feldspar granite, i.e. the late crystallization age of the K-feldspar granite intrusion, which indicates that the K-feldspar granite formed in the intraplate extensional stage during the Early Permian. Moreover, based on the spatial relationship between the K-feldspar granite intrusion and copper orebodies, variations of copper ore grade, REE characteristics of K-feldspar granite and copper ores, and H and O isotopic compositions of fluid inclusions in copper ores, the metallogenesis of the Qiaohuote copper deposit is directly related to intrusive activities of the K-feldspar granite, and thus the crystallization age of K-feldspar in the granite approximately approaches the metallogenic epoch of the Qiaohuote copper deposit.

关键词： 40Ar-39Ar age K-feldspar granite Qiaohuote Xinjiang

Re-Os Age of Cu-Ni Ores from the Huangshandong Cu-Ni Sulfide Deposit in the East Tianshan Mountains and Its Implication for Geodynamic Processes

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Acta Geologica Sinica(English Edition) 2003年第2期77卷 220-226页

作者： MAOJingwen yangjianmin QUWenjun DUAndao WANGZhiliang HANChunming FacultyofGeosciencesandResources ChinaUniversityofGeosciencesBeijing100083 InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037 NationalResearchCenterofGeoanalysis ChineseAcademyofGeologicalSciencesBeijing100037

An isochron age of 282±20 (95% conf. limit) Ma of the sulfide ores in the Huangshandong Cu-Ni sulfide deposit, the East Tianshan Mountains has been obtained through Re-Os isotopic measurement. The age implies that the Cu-Ni sulfide deposit and other related deposits in the same area occurred in a Permian extensional environment of post-collision instead of Devonian-Early Carboniferous ophiolite-related oceanic or island arc environments inferred before. It shares the same ages with the orogenic and epithermal gold deposit systems in the same area. An initial 187Os/188Os ratio of 0.25±0.04 (1σ) and a γos value of 99 on average display the participation of large quantities of crustal components into the rock-forming and ore-forming system during mineralization and magmatic emplacement.

关键词： Huangshandong Cu-Ni sulfide deposit East Tianshan mountains Permian Re-Os age

Episodes of Cenozoic Gold Mineralization on the Eastern Margin of the Qinghai-Tibet Plateau:40Ar/39Ar Dating and Implication for Geodynamic Events

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Acta Geologica Sinica(English Edition) 2005年第2期79卷 233-253页

作者： WANGDenghong MAOJingwen YANShenghao yangjianmin XUJue CHENYuchuan XUEChunji InstituteofMineralResources ChineseAcademyofGeologicalSciencesBeijing100037 ChineseAcademyofGeologicalSciences Beijing100037 DepartmentofGeologicalSciences Chang＇anUniversityXi＇anShaanxi710000

A lot of new gold deposits have been found on the eastern margin of the Qinghai-Tibet Plateau during the past two decades. Among them, three main types of gold deposits have been recognized, including quartz-vein-type, shear- zone-type and porphyry-type. The former two types of gold deposits are mainly hosted within metamorphic rocks, while the latter is related to Cenozoic magmatism. Although all of these gold deposits are believed to have been formed during the uplift process of the Qinghai-Tibet Plateau in the Cenozoic era (Wang et al., 2002b), precise isotopic age constraints have still been lacking until quite recently. This paper presents new 40Ar/39Ar data of some gold deposits on the eastern margin of the Qinghai-Tibet Plateau, which indicate that gold mineralization in the region occurred in response to the episodic stages of the orogenies. Recently obtained 40Ar/39Ar data on quartz and feldspars from several gold deposits, such as the Sandiao deposit, the Baijintaizi deposit, the Pusagang deposits, provide new constraints on gold mineralization on the eastern margin of the Qinghai-Tibet Plateau. Geochronological studies of gold deposits along the Daduhe River indicate that there are three stages of gold mineralization. The early two stages occurred as early as 65.1 Ma in the Shuibaiyang deposit and 58.95 Ma in the Ruoji deposit, while the latter stage occurred as late as 25.35 Ma in Baijintaizi and 24.70 Ma in Sandiao. Isotopic dating of three plagioclases from the Beiya deposit, Zhifanggou deposit and Luobodi deposit and a K-feldspar from the Jinchangqing deposit in Yunnan Province indicates that these deposits were formed at two stages. The Zhifanggou and Jinchangqing deposits have early stage records as old as 58.82 Ma in Zhifanggou and 55.49 Ma in Jinchangqing, but all of the above four deposits in Yunnan have late stage records of 23.18 Ma in Jinchangqing, 24.54 Ma in Zhifanggou, 24.60 Ma in Luobodi and 24.56 Ma in Hongnitang. The above results sugges

关键词： Southwestern China eastern margin of the Qinghai-Tibet Plateau gold deposit metallogenic episodes Sichuan Yunnan the Himalayas Cenozoic

Current status of poly culture and rotation culture in Chinese mariculture industry

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Acta Oceanologica Sinica 2004年第3期23卷 505-512页

作者： WANGRucai yangjianmin ZHENGXiaodong FisheryCollege OceanUniversityofChinaQingdao266003China MarineFisheriesResearchInstituteofShandongProvince Yantai264000China

The status of polyculture and rotational culture in Chinese marine life is reviewed. Some successful experience is summarized.

关键词： polyculture rotation culture manculture