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Lady Bountiful脉金矿床位于中绿片岩相变质的Ora Banda绿岩层中,主要以构造晚期Liberty花岗闪长岩为主岩。金矿化沿石英脉状的,左旋的脆性断裂带产出,此断裂带横切Liberty花岗闪长岩和Pleasant山岩床。石英脉的结构表明,与金有关的单脉发育分为2个阶段,高品位矿化局限于第2阶段。矿石矿物包括黄铁矿、黄铜矿、磁黄铁矿、方铅矿、闪锌矿、Au-Ag-Bi-Pb-碲化物和自然金。流体渗滤导致此断裂带具狭窄的退色围岩蚀变包壳,并含有钠长石-钾云母-绿泥石±方解石±金红石集合体。2个阶段的热液流体特征为X(CO_2)≤0.15和中等盐度(1.28mNaCl)。由膨胀部位压力波动而引起的第2阶段矿化流体的间歇析出和(或)流体占优势的流体-围岩相互反应是金主要的沉淀机制。
The Lady Bountiful Veins deposit is located in the mid-greenschist facies Ora Banda greenstone formation, mainly composed of late-stage Liberty granodiorite. Gold mineralization occurs along quartz veins, left-handed brittle fracture zones that cross the Liberty granodiorite and Pleasant rock beds. The structure of the quartz veins shows that gold-related monomorphic development is divided into two stages and high-grade mineralization is limited to stage two. Ore minerals include pyrite, chalcopyrite, pyrrhotite, galena, sphalerite, Au-Ag-Bi-Pb-telluride and natural gold. Fluid percolation resulted in a narrow faded faulted enclave of this fault with an alteration of albite-kaolinite-chlorite ± calcite ± rutile assemblages. The two phases of hydrothermal fluids are characterized by X (CO 2) ≤ 0.15 and moderate salinity (1.28 mNaCl). Intermittent precipitation of the second stage mineralized fluid and / or fluid-dominated fluid-surrounding rock interaction caused by pressure fluctuations in the swollen parts are the main precipitation mechanisms.