The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted thr...The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted three-phase inclusions. The fluid inclusions are characterized by low salinity (5%-9% NaCl eqv) , low density (0.66-0.72 g/cm^3 ) and medium temperature (210℃-250℃). The pressure of ore-forming is 60-95 MPa and the metallogenic depth is about 5.49-7.56 km. During the mineralizing process, ore-forming fluid under- went fluid unmixing in CO2-H2O-NaCl system. The stable isotope resuhs indicate that the ore-forming fluids mainly generated from mantle, with the participation of a small amount of atmospheric water. Comprehensive studies have suggested that Qiangsheng gold deposit belongs to the type of mesothermal hydrotherm with mantlederived fluid participating in mineralization.展开更多
The combination of field surveys with analysis of microstructure of tectonite and Electron Backscatter Diffraction(EBSD) on quartz fabric indicated that three periods of ductile shear events developed in the Paishanlo...The combination of field surveys with analysis of microstructure of tectonite and Electron Backscatter Diffraction(EBSD) on quartz fabric indicated that three periods of ductile shear events developed in the Paishanlou gold deposits and the E-W and NE-striking ductile shear zones were formed during each event.The E-W-striking ductile shear zone,accompanied by compressional and dextral shear slip,was shear-cut by the NE-striking shear zones,accompanied by compressional-sinistral shear slip and sinistral-normal shear slip,successively.An E-W-striking ductile shear zone developed at a deeper tectonic level and at middle- to high-temperatures,accompanied by abundant microstructures,including microlayering between a polycrystal quartz belt and mica,and quartz deformation was depended on cylinder(10-10) or <c> glide.The development of an E-W-striking shear zone can be seen as a tectonic pattern in the region of the Paishanlou gold deposits of the collision between the Mongolian tectonic belt and the North Archean Craton from Suolun to the Linxi suture zone during the Indosinian.The NE-striking ductile shear zone developed approximately 160 Ma during the early Yianshanian at middle to shallow tectonic levels and at middle- to low-temperatures,accompanied by typical microstructures,including polycrystal quartz aggregation and quartz subgrain rotation recrystallization,etc.,and quartz deformation was depended on prismatic(1011) glide.The last ductile shear event around the NE-striking shear zone developed at low temperatures and shallow tectonic levels,yielding to a pre-existing NE-striking shear zone,accompanied by abundant microstructures,including low-temperature quartz grain boundary migration and bulging recrystallization.The last ductile shear movement may be related to lithosphere thinning and the destruction of the North China Craton from approximately 130-120 Ma,and this shear event resulted directly in the mineralization in the Paishanlou region.展开更多
基金Supported by projects of Geological Exploration of Jilin Province(No.22201300111)Shanhou Gold Deposit of Laixi of Shandong Province(SDLX2012-3-28)
文摘The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types: aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted three-phase inclusions. The fluid inclusions are characterized by low salinity (5%-9% NaCl eqv) , low density (0.66-0.72 g/cm^3 ) and medium temperature (210℃-250℃). The pressure of ore-forming is 60-95 MPa and the metallogenic depth is about 5.49-7.56 km. During the mineralizing process, ore-forming fluid under- went fluid unmixing in CO2-H2O-NaCl system. The stable isotope resuhs indicate that the ore-forming fluids mainly generated from mantle, with the participation of a small amount of atmospheric water. Comprehensive studies have suggested that Qiangsheng gold deposit belongs to the type of mesothermal hydrotherm with mantlederived fluid participating in mineralization.
基金supported by National Crisis Mine Program(Grant No.20089931)National Natural Science Foundation of China(Grant Nos.90814006,91214301,41172089)Foundation of Shandong Provincial Key Laboratory of Depositional Mineralization&Sedimentary Minerals(Grant No.DMSM201005)
文摘The combination of field surveys with analysis of microstructure of tectonite and Electron Backscatter Diffraction(EBSD) on quartz fabric indicated that three periods of ductile shear events developed in the Paishanlou gold deposits and the E-W and NE-striking ductile shear zones were formed during each event.The E-W-striking ductile shear zone,accompanied by compressional and dextral shear slip,was shear-cut by the NE-striking shear zones,accompanied by compressional-sinistral shear slip and sinistral-normal shear slip,successively.An E-W-striking ductile shear zone developed at a deeper tectonic level and at middle- to high-temperatures,accompanied by abundant microstructures,including microlayering between a polycrystal quartz belt and mica,and quartz deformation was depended on cylinder(10-10) or <c> glide.The development of an E-W-striking shear zone can be seen as a tectonic pattern in the region of the Paishanlou gold deposits of the collision between the Mongolian tectonic belt and the North Archean Craton from Suolun to the Linxi suture zone during the Indosinian.The NE-striking ductile shear zone developed approximately 160 Ma during the early Yianshanian at middle to shallow tectonic levels and at middle- to low-temperatures,accompanied by typical microstructures,including polycrystal quartz aggregation and quartz subgrain rotation recrystallization,etc.,and quartz deformation was depended on prismatic(1011) glide.The last ductile shear event around the NE-striking shear zone developed at low temperatures and shallow tectonic levels,yielding to a pre-existing NE-striking shear zone,accompanied by abundant microstructures,including low-temperature quartz grain boundary migration and bulging recrystallization.The last ductile shear movement may be related to lithosphere thinning and the destruction of the North China Craton from approximately 130-120 Ma,and this shear event resulted directly in the mineralization in the Paishanlou region.