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对加拿大不列颠哥伦比亚南部布莱克多姆(Blackdome)矿区的始新世浅成热液Ag-Au-(Sb-Cu-Fe-Zn-Pb-S-Se-As)矿床进行了溶液包体研究和稳定同位素分析。贵金属矿脉赋存于钙-碱性火山岩系内,是大气成因地下水在地表以下0.5—1.1km渗入火山堆积物的裂隙而发育形成的矿床。部分裂口,由于沸腾地热系统和水流体的影响,使主岩岩石形成层状硅酸盐及钾长石化蚀变。火山岩主岩的普遍青磐岩化表示它以前具地热田的特征。地热溶液为低盐度-0.21-2.07wt％NaCl,密度为0.72-0.81g/cm~3,δ~(18)O值为-6.8至-8.8‰(SMOW),δD值为-125至-134‰(SMOW)。在含水的交代作用时期,氧同位素交换造成偏离“雨水线”的正位移。少数在δD值内正位移,偏离原生雨水线的数值是因为氢从裂口系统或与围岩的氢选择交代作用而发生亏损。Blackdome矿床明显属于冰长石-绢云母型的火山岩主岩浅成热液贵金属矿床。
Solution inclusions were studied and stabilized in the Eocene epithermal Ag-Au- (Sb-Cu-Fe-Zn-Pb-S-Se-As) deposits in the Blackdome mining area in southern British Columbia, Canada Isotope analysis. Precious metal veins occur in calcium-alkaline volcanic rocks and are formed by the infiltration of volcanic sediments into the fractures of volcanic deposits at a depth of 0.5-1.1 km beneath the surface due to the formation of atmospheric origin. Part of the rift, due to the boiling geothermal system and the influence of water fluid, causes the host rocks to form phyllosilicate and potassium feldspar alteration. The widespread metamorphism of the volcanic host rock signifies its former geothermal field character. The geothermal solution is low salinity -0.21-2.07wt% NaCl, with a density of 0.72-0.81g / cm 3, a δ 18 O value of -6.8 -8.8 ‰ (SMOW), a δD value of -125 to - 134 ‰ (SMOW). Oxygen isotope exchange caused a positive shift away from the “storm line” during the hydroponic metasogenesis. A small number of positive displacements within the δD values that deviate from the primary rainline are due to the loss of hydrogen due to selective sequestration of hydrogen from the rip system or from the surrounding rock. The Blackdome deposit apparently belonged to the feldspar-sericite volcanic host magmatic epithermal precious metal deposit.