| Eastern Kunlun orogenic belt is located in the south of Qaidam block,belonging to the western segment of the Central China Orogenic . The regional geologic settings are very complicated including diverse regional strata, magmatic rocks and structures. Three EW-striked regional are North Eastern Kunlun, Middle Eastern Kunlun and South Eastern Kunlun faults are recognized.Based on the three regional falults,the former researchers divided the area into three tectonic units .On the basis of regional geologic settings,combining the research achievement of formers and our field survey for several years,we consider that geologic meanings of the above three tectonic belts were Qaledonian back-arc rift belt of North of Eastern Kunlun, basement uplifting and granite belt of Middle of Eastern Kunlun and composite collage belt of South of Eastern Kunlun. Eastern Kunlun was a long-term active orogenic belt and went through complicated geodynamic evolution. Eastern Kunlun southern belt was steady oceanic settings before Caledonian and formed Wanbaogou basalt plateau by mantle plume movement until Meso-Neoproterozoic.The basalt plateau located in the ocean which was far from Qaidam block.On late Caledonian, W-anbaogou basalt plateau was directly converged with southern margin of Qaidam block along faults of middle of Easten Kunlun. Then the subduction zone moved to the fault of South of Eastern Kunlun.In early middle Silurian, hydrothermal sedimentation rock -siliceous albitite was formed in the extensional tectonic setting of Wanbaogou oceanic basalt plateau.It supplied the benefit condition for the formation of SEDEX deposits,controlling the occurrence of Tuolugou Co deposits. On early indosinian ,the whole Easten Kunlun orogenic belt came into a stage of intracontinental evolution.marginal orogenesis had ended.After then,Eastern Kunlun southern belt went through regional metamorphose,tectonism and magmatism in Indosinian-Yanshanian stage,which caused the strata in Tuolugou area fold deformation and fault. Tuolugou Co deposit is a newly discovered independent Co deposit in the southern margin of Eastern Kunlun orogen.Prospecting evaluation is going on.The reserves of ores reach the medium-size and the industry prospect is favorable. The strata in the Tuolugou ore district is sea facies pelitic arenaceous sedimentary rocks, intermediate-acid volcanic rocks, hydrothermal sedimentation rocks,and also can find granite-porphyry intrusive rocks.When it comes to the age of strata,there are two views about it,some believe it is permian Maerzheng formation,others think it is sinian-cambrian. However,we affirm that the strate must be lower and middle Silurian since we find the foam coral fossil belonged to early-middle Silurian. Based on study of geological characteristics and geochemistry of Tuolugou Co deposit,we consider that the ore deposit mainly relates to hydrothermal exhalation sedimentation metallogenesis. Ore-bearing rock series are mostly lower Silurian low green schist facies metamorphic volcanic-sedimentary detrital rocks,which are composed of sercite-quartz schist,chlorite sercite-quartz schist and siliceous albitite.Through research,sili-ceous albitite is not dikes but typical hydrothermal sedimentary rock. In addition,it also is an important indicator for ore prospecting . As the direct wall rock of Co orebody,siliceous albitite obviously enriches several elements,such as Co,Au,Cu,Ni,As,Hg,Sb.This kind of rocks are matter foundation of metallogenetic element enriching and depositing. The types of ores are single and mainly made up of pyrite ores.The amount of indepdent Co minerals is little.Co mostly exists pyrite.According to the ore structure and generation of ore minerals,it suggested that Tuolugou Co deposit underwent hydrothermal exhalation sedimentation metallogenesis and later phase structure deformation and reform. laminar sulfide ore bodies andhydrothermal sedimentation rocks can be formed during the early hydrotherm-al exhalation sedimentation metallogenesis. After the minerali-zation, later structural deformation altered the ore body ,making the ore body deformation or re-orientation. Ore bodies were characteristic of"stratiform but not bed,veinlike but not vein".This alteration had not taken place new metallogenesis.The study of later deformation and reform in the ore district take an important significane in the arrange of ore exploring works. Based on the study of Tuolugou specularite ore deposit ,located in the northeast of ore district.We think that the ore deposit is controlled by fault structure and belongs to hydrothermal vein deposit .Furthermore, the specular-arite ore deposit related to granite-porphyry.Co mineralinzation did not related to later stage specularite ,but was interrelated to sulfide formed by hydrothermal function in early stage.The discover of the specularite ore deposit suggests that there are two types of Co mineralinzation in the Tuolugou ore district.One is hydrothermal exhalation sedimentation Co mineralinzation,the other is hydrothermal vein Co mineralinzation. The occur of hydrothermal vein Co mineralinzation makes Tuolugou Co depposit's prospecting Potential and range enlarge. On the basis of the analyzing of ore-controlling condition and metallogen-ic regularity ,we found out the prospecting indictions of Tuolugou ore deposit and evaluated the prospecting potenial.The rock member of chlorite sercite-qu-artz schist and siliceous albitite(S1a-3) is the important strata prospecting indiction,which is ore-bearing strata. siliceous albitite is petrology prospecting indiction,which is always connecting with orebody.The obvious borwn-yellow jarosite alteration zone in the earth's surface often indicates the enrichment segment of Co mineralinzation,which may be regarded as the earth's surface direct prospecting indiction. Eastern Kunlun southern belt is enriching all kinds of metal elements,such as Co,Cu,Au,Pb,Zn(Hg,Sb),metallogenic belt.Wanbaogou groups in the Eastern Kunlun southern belt consist of one or several ocean islands on the oceanic crust.Under the oceanic crust settings,the large geothermal gradient ,...
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