The superlarge Baguamiao, large Liba and Xiaogouli gold deposits represent three typical gold deposits different from the Carlin type in the western Qinling Orogenic Belt. Based on Ar-Ar dating of quartz from ores, U-...The superlarge Baguamiao, large Liba and Xiaogouli gold deposits represent three typical gold deposits different from the Carlin type in the western Qinling Orogenic Belt. Based on Ar-Ar dating of quartz from ores, U-Pb dating of single zircon from granite, tracing of H and O isotopes and studies on the mineralogy and texture of spots and bleached alteration developed in wall rocks, this paper focuses the relations between gold deposits and granite to clarify the origin of gold deposits and the metallogenesis in the tectonic evolution of the Qinling Orogenic Belt. The comprehensive studies show that the age of the granite (148.1-244 Ma) is identical with that of the gold deposits (131.91-232.56 Ma). It is suggested that the granite has close temporal, spatial and genetic relationship with the gold deposits. The granite provides a heat source, water source and considerable amount of ore-forming material. Finally, it is concluded that the orogeny by collision, emplacement of the granite and positioning of the gold deposits represent a successive process. Both the granite and gold deposits resulted from the syn-orogeny and post-orogeny tectonic evolution.展开更多
A series of ductile shear zones of the overthrust and strike-slip-types and related ductile shear metamorphicrocks, including tectonic melange and mylonites. were formed in the core of the Qinling orogenic belt in the...A series of ductile shear zones of the overthrust and strike-slip-types and related ductile shear metamorphicrocks, including tectonic melange and mylonites. were formed in the core of the Qinling orogenic belt in thecourse of the Caledonian-Indosinian ductilc and brittle-ductile reworking. The study on their petrography. va-riations in composition and conditions of formation is conducive to revealing the metamorphism-deformationhistory of the core of the Qinling orogenic belt and further to understanding the dynamic mechanism of its evo-lution.展开更多
文摘The superlarge Baguamiao, large Liba and Xiaogouli gold deposits represent three typical gold deposits different from the Carlin type in the western Qinling Orogenic Belt. Based on Ar-Ar dating of quartz from ores, U-Pb dating of single zircon from granite, tracing of H and O isotopes and studies on the mineralogy and texture of spots and bleached alteration developed in wall rocks, this paper focuses the relations between gold deposits and granite to clarify the origin of gold deposits and the metallogenesis in the tectonic evolution of the Qinling Orogenic Belt. The comprehensive studies show that the age of the granite (148.1-244 Ma) is identical with that of the gold deposits (131.91-232.56 Ma). It is suggested that the granite has close temporal, spatial and genetic relationship with the gold deposits. The granite provides a heat source, water source and considerable amount of ore-forming material. Finally, it is concluded that the orogeny by collision, emplacement of the granite and positioning of the gold deposits represent a successive process. Both the granite and gold deposits resulted from the syn-orogeny and post-orogeny tectonic evolution.
文摘A series of ductile shear zones of the overthrust and strike-slip-types and related ductile shear metamorphicrocks, including tectonic melange and mylonites. were formed in the core of the Qinling orogenic belt in thecourse of the Caledonian-Indosinian ductilc and brittle-ductile reworking. The study on their petrography. va-riations in composition and conditions of formation is conducive to revealing the metamorphism-deformationhistory of the core of the Qinling orogenic belt and further to understanding the dynamic mechanism of its evo-lution.
