There are six distinct classes of gold deposits, each represented by metallogenic provinces, having 100’s to 】 1 000 tonne gold production. The deposit classes are: (1) erogenic gold; (2) Carlin and Carlin-like gold...There are six distinct classes of gold deposits, each represented by metallogenic provinces, having 100’s to 】 1 000 tonne gold production. The deposit classes are: (1) erogenic gold; (2) Carlin and Carlin-like gold deposits; (3) epithermal gold-silver deposits; (4) copper-gold porphyry deposits; (5) iron-oxide copper-gold deposits; and (6) gold-rich volcanic hosted massive sul-fide (VMS) to sedimentary exhalative (SEDEX) deposits. This classification is based on ore and alteration mineral assemblages; ore and alteration metal budgets; ore fluid pressure(s) and compositions; crustal depth or depth ranges of formation; relationship to structures and/or magmatic intrusions at a variety of scales; and relationship to the P-T-t evolution of the host terrane. These classes reflect distinct geodynamic settings. Orogenic gold deposits are generated at mid-crustal (4-16 km) levels proximal to terrane boundaries, in transpressional subduction-accretion complexes of Cordilleran style erogenic belts; other展开更多
As an effective tracer, nitrogen isotopes have been used to determine the source of ore materials in recent years. In this study, the nitrogen isotopes and contents were measured on K- feldspar and sericite of gold de...As an effective tracer, nitrogen isotopes have been used to determine the source of ore materials in recent years. In this study, the nitrogen isotopes and contents were measured on K- feldspar and sericite of gold deposits and some related granitic intrusions in Jiaodong, Xiao-qinling-Xiong抏rshan, west Qinling, the west part of North Qilian and the Zhangjiakou-Xuanhua district around the North China craton (NCC). Although the gold deposits around the NCC are hosted in Precambrian metamorphic rocks, Phanerozoic sedimentary rocks, mafic volcanic rocks or granite, comparison of which with the nitrogen contents and isotope data of previous studies on mantle-derived rocks, granites, metamorphic rocks and gold deposits indicates that those deposits are closely related to granitic rocks. In addition, mantle-derived materials may have been involved in the ore-forming processes to a certain degree. This conclusion is consistent with the result of previous hydrogen, oxygen and carbon isotopic studies of those gold deposits.展开更多
文摘There are six distinct classes of gold deposits, each represented by metallogenic provinces, having 100’s to 】 1 000 tonne gold production. The deposit classes are: (1) erogenic gold; (2) Carlin and Carlin-like gold deposits; (3) epithermal gold-silver deposits; (4) copper-gold porphyry deposits; (5) iron-oxide copper-gold deposits; and (6) gold-rich volcanic hosted massive sul-fide (VMS) to sedimentary exhalative (SEDEX) deposits. This classification is based on ore and alteration mineral assemblages; ore and alteration metal budgets; ore fluid pressure(s) and compositions; crustal depth or depth ranges of formation; relationship to structures and/or magmatic intrusions at a variety of scales; and relationship to the P-T-t evolution of the host terrane. These classes reflect distinct geodynamic settings. Orogenic gold deposits are generated at mid-crustal (4-16 km) levels proximal to terrane boundaries, in transpressional subduction-accretion complexes of Cordilleran style erogenic belts; other
基金This work was supported by the Ministry of Science and Technology of China (Grant No. G1999043211).
文摘As an effective tracer, nitrogen isotopes have been used to determine the source of ore materials in recent years. In this study, the nitrogen isotopes and contents were measured on K- feldspar and sericite of gold deposits and some related granitic intrusions in Jiaodong, Xiao-qinling-Xiong抏rshan, west Qinling, the west part of North Qilian and the Zhangjiakou-Xuanhua district around the North China craton (NCC). Although the gold deposits around the NCC are hosted in Precambrian metamorphic rocks, Phanerozoic sedimentary rocks, mafic volcanic rocks or granite, comparison of which with the nitrogen contents and isotope data of previous studies on mantle-derived rocks, granites, metamorphic rocks and gold deposits indicates that those deposits are closely related to granitic rocks. In addition, mantle-derived materials may have been involved in the ore-forming processes to a certain degree. This conclusion is consistent with the result of previous hydrogen, oxygen and carbon isotopic studies of those gold deposits.
