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对美国业利桑那州中西部三个块状硫化矿床进行了土壤汞的地球化学测量。测量结果表明,这种技术对半干旱区(如美国西南部)块状硫化矿床的勘查可能具有普遍的适用意义。所研究的矿床均产于前寒武纪变质火山岩和变质沉积岩中。Bagdad地区南边的Old Dick矿床上,在铁帽和占矿体产出的地区有一个500ppb以上宽而强的土壤汞异常。在一条通过埋藏在地表下150水深处矿体上方的横剖面上获得了一个在铁帽上所得出的相同的响应。在Old Dick矿床南面大约1000米的CopperQueen矿床上,仅得到了一个弱的土壤汞的响应。一个约100ppb的汞的区域异常下限圈出了Old Dick地区所有已知矿化分布的范围。在Drescott东面的Binghampton地区土壤汞剖面通过二个平行的块状硫化矿透镜体,剖面上出现了一个200～1000ppb宽而强的汞异常,其背景值约为50ppb。在King man东南面的Antler矿山上,异常值仅出现在铁帽或容矿的石英—黑云母片岩中。 Old Dick和Binghampton地区的土壤汞晕雄辩地表明在块状硫化矿体的围岩中存在着深成汞晕。这种深成汞晕比相应的块状硫化矿体大得多,而且很可能是矿产勘查中所能发现的汞异常的主要来源。深成汞晕的大小和强度可能和形成块状硫化物的热液系统的距离有关,也和它的成熟度有关。范围大的深成汞晕看来是与靠近火山中心或一个壮年期的成矿热液系统所形成的块状硫化矿伴生的;而弱的深成汞晕可能是与远离火山口或与在一个老年期的成矿热液系统沉积所形成的块状硫化物伴生的。
Geochemical measurements of soil mercury were performed on three massive sulphide deposits in the Midwest, Arizona, USA. The measurements show that this technique may be of general relevance for the exploration of massive sulphide deposits in semi-arid zones such as the southwestern United States. The deposits studied are all produced in Precambrian metamorphic volcanics and metamorphic sedimentary rocks. The Old Dick deposit to the south of the Bagdad area has a broad and strong soil mercury anomalies above 500 ppb in areas of the iron cap and ore bodies. A similar response on the iron cap was obtained on a cross-section that was buried above the surface at a depth of 150 m. On the CopperQueen deposit about 1,000 meters south of the Old Dick deposit, only a weak soil mercury response was obtained. An area lower limit of about 100 ppb of mercury circles the range of all known mineralization in the Old Dick area. The soil mercury profile in the Binghampton area east of Drescott passes through two parallel massive sulphide lens bodies with a broad and strong mercury anomaly of 200-1000 ppb in the profile with a background value of about 50 ppb. On the Antler mine southeast of the King man, outliers occur only in the iron cap or in the hosted quartz-biotite schist. Soil amalgam in the Old Dick and Binghampton eloquently indicates that there is deep halo of mercury in the surrounding rock of massive sulphide ore bodies. This deep-formed mercury halo is much larger than the corresponding massive sulphide orebodies and is probably the major source of mercury anomalies found in mineral exploration. The size and intensity of the deep mercury halo may be related to the distance of hydrothermal systems that form massive sulphides and to its maturity. A large range of deep mercury ghosts appear to be associated with massive sulphide minerals formed near the volcano center or a mantle hydrothermal fluid system; while the weak deep mercury gusts may be associated with or away from the crater An older metazoan mineralization formed by the deposition of massive sulphide associated.