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火山岩中的块状硫化物矿床的金属成分呈-连续的系列,即以铜为主的塞浦路斯型到富铅的黑矿型锌(+铜)矿床.人们认为这个系列是大离子亲石元素在矿石中(如 Pb、Ba)、岩浆体系中(如 K)以及在矿床形成过程中富集的结果.因此,火山岩中的富铅块状硫化物矿床都与成熟岛弧体系(如巴肯斯)或与弧后钙碱性岩浆作用有关.在这些地方.较老的大陆壳也卷入了岩浆成因.该系列另一端的富铜矿石与超俯冲带蛇绿岩杂岩体中的斜长花岗岩有关,而大离子亲石元素则很少富集,铜锌块状硫化物矿床赋存在古弧后集合体而今是绿岩带中,并与拉斑玄武质-钙碱性岩浆体系有关,其大离子亲石元素只有中等程度的富集.笔者认为,这些矿石中的金属成分和同时代侵人体的化学成分的变化基本上与其在岛弧和弧后体系的位置,以及俯冲作用持续的时间有关.
The metalloids of the massive sulphide deposits in the volcanic rocks are in a continuous series, that is, the copper-dominated Cyprus-to-Pb-rich black ore type of zinc (+ copper) deposits.It is believed that this series is a large ionic lithophile element (Pb, Ba), magmatic systems (such as K), and the enrichment during the formation of the deposit, the Pb-rich massive sulphide deposits in volcanic rocks are associated with mature island arc systems ) Or associated with post-arc calc-alkaline magmatism where older continental crusts were also involved in magmatic origin.The copper-rich ores at the other end of this series, along with the ultra-subduction zone ophiolite complex Long granite, whereas large ionophilic lithofacies are seldom enriched. Cu-Zn massive sulfide deposits occur in the paleo-arc retrograde assemblages and are now greenstone belts and are associated with tholeiite basaltic-calc-alkaline magmatic systems , And its large ion-lithophile elements are only moderately enriched.The author believes that the changes of the chemical composition of the metal components and contemporaneous intrusions in these ores are basically related to their position in the island arc and the backarc system, and the subduction continues Of the time.