The Hongshijing gold deposit, which occurs in the Middle and Late Carboniferous volcanic and pyroclastic rocks, is of the brittle-ductile sh ear zone type controlled by a rift belt. The Hongshijing gold deposit is one...The Hongshijing gold deposit, which occurs in the Middle and Late Carboniferous volcanic and pyroclastic rocks, is of the brittle-ductile sh ear zone type controlled by a rift belt. The Hongshijing gold deposit is one con trolled by a brittle shear zone located in the Late Paleozoic rift zone. The alt ered-rock type and quartz type orebodies are contained in the gold-bearing for mation, which consists of basalt and tuffaceous sandstone. The major mineralizin g stage is at 267-261 Ma and reiteration mineralizing stage at 220-209 Ma.The or e minerals include pyrite, magnetite, copper, bornite, ferrohydrite, native gold , and the gangue minerals include quartz, sercite, calcite, Fe-dolomite, leucox ene, anorthose, biotite, baria, cajuelite, and agustite. The wall rock alteratio n associated with gold mineralization comprises silicification, carbonization, p yritization, sericitization and chloritization. The contents of gold are \{2.4\} ×10\+\{-9\} in the gold-bearing formation, \{5.7\}×10\+\{-9\} in the tuffaceo us sandstone and \{1.4\}-\{1.5\}×10\+\{-9\} in the basalt. Au is associated wit h Te, Se, Ni, Cu. Au=\{74.331\}×Te+\{0.0335\}×Ni-\{0.0211\}×Cu-\{2.650\}. Geo chemical investigations revealed that the mineralizing materials came from the b asalt and tuffaceous sandstone in the gold-bearing formation. Under the action of ductile brittle shear structure, the gold-bearing formation was metamorphose d and altered, and the ore-forming materials activated, migrated and mineralize d. The mineralizing fluid shows three mineralizing stages, with the characterist ics of middle to low temperature and middle to low mass fractions of NaCl .The fluid is of the Ca\+\{2+\}-Mg\+\{2+\}-Na\++- Cl\+- type and H\-2O-NaCl system. According to the data from hydrogen and oxyge n isotopic composition (δD=\{-114.6‰\}-\{-68.8‰\}, \{δ\{\}\+\{18\}O\-\{H\-2O \}\}=\{-2.47‰\}-\{5.91‰\}), the conclusion can be drawn that the mineralizing fluid of the Hongshijing gold deposit was a kind of mixed hydrothermal solution composed展开更多
文摘The Hongshijing gold deposit, which occurs in the Middle and Late Carboniferous volcanic and pyroclastic rocks, is of the brittle-ductile sh ear zone type controlled by a rift belt. The Hongshijing gold deposit is one con trolled by a brittle shear zone located in the Late Paleozoic rift zone. The alt ered-rock type and quartz type orebodies are contained in the gold-bearing for mation, which consists of basalt and tuffaceous sandstone. The major mineralizin g stage is at 267-261 Ma and reiteration mineralizing stage at 220-209 Ma.The or e minerals include pyrite, magnetite, copper, bornite, ferrohydrite, native gold , and the gangue minerals include quartz, sercite, calcite, Fe-dolomite, leucox ene, anorthose, biotite, baria, cajuelite, and agustite. The wall rock alteratio n associated with gold mineralization comprises silicification, carbonization, p yritization, sericitization and chloritization. The contents of gold are \{2.4\} ×10\+\{-9\} in the gold-bearing formation, \{5.7\}×10\+\{-9\} in the tuffaceo us sandstone and \{1.4\}-\{1.5\}×10\+\{-9\} in the basalt. Au is associated wit h Te, Se, Ni, Cu. Au=\{74.331\}×Te+\{0.0335\}×Ni-\{0.0211\}×Cu-\{2.650\}. Geo chemical investigations revealed that the mineralizing materials came from the b asalt and tuffaceous sandstone in the gold-bearing formation. Under the action of ductile brittle shear structure, the gold-bearing formation was metamorphose d and altered, and the ore-forming materials activated, migrated and mineralize d. The mineralizing fluid shows three mineralizing stages, with the characterist ics of middle to low temperature and middle to low mass fractions of NaCl .The fluid is of the Ca\+\{2+\}-Mg\+\{2+\}-Na\++- Cl\+- type and H\-2O-NaCl system. According to the data from hydrogen and oxyge n isotopic composition (δD=\{-114.6‰\}-\{-68.8‰\}, \{δ\{\}\+\{18\}O\-\{H\-2O \}\}=\{-2.47‰\}-\{5.91‰\}), the conclusion can be drawn that the mineralizing fluid of the Hongshijing gold deposit was a kind of mixed hydrothermal solution composed
