大厂锡-多金属矿床热释汞测量技术条件、异常特征及成晕机制

在大厂长坡锡矿采集土壤、岩石及矿体(矿石)样品共280个,开展了热释汞测量技术条件、异常特征及成晕机制的研究,结果表明:大厂长坡锡一多金属矿床的热释汞,在空间上随矿体赋存明显呈由下到上的"三层楼"式分布,即下部似层状矿体含汞量<中部细脉型矿体汞量<上部裂隙脉型矿体汞量,汞随矿体沿构造滑脱面及裂隙带上升运移;在平面上似层网脉状矿体中部含汞量高,边部低,细脉状矿体边部高中间低,裂隙脉矿群底部低,顶部高,清晰地体现了汞运移扩散的路径.根据汞的运移和赋存形式推判汞异常形成过程为汞伴随深大断裂和多次的岩浆入侵上升,并在成矿过程中赋存于富含硫化物的矿床中,良好的容矿构造和矿石围岩岩性保障了汞的运移和赋存.

MEASUREMENT CONDITION AND ABNORMITY CHARACTER OF HEAT-RELEASED MERCURY METHOD IN THE CHANGPO TIN POLYMETALLIC DEPOSIT AT DACHANG

280 rock and ore samples were collected in the Changpo tin-polymetallic deposit at Dachang. The analytic results show that heat-released mercury (HR-Hg) in the Changpo tin-polymetallic deposit is distributed like three-layer pattern in space. HR mercury increases from layer-like ores (bottom) to thin-vein ores (middle) and to fissure-vein ores. Mercury moves up along with structural slippage planes and fracture zones. In plane, HR-Hg content in the middle parts of layer-like ores is higher than that in the two edges, and in reverses order in fine vein ores. HR-Hg content in the bottom of fissure-vein ore bodies is higher than the that in the top, obviously showing the pattern and movement of Hg. It is inferred that mercury moved upwards along deep fault and storied in sulphide-rich deposits.