清原县下大堡金矿控矿因素及找矿方向

通过对辽北下大堡金矿的主要成矿元素及成矿流体的热量、来源， 以及韧性剪切带与成矿的关系研究， 认为下大堡断裂次一级北西向张扭性断裂形成后， 燕山晚期安山玢岩侵入， 在安山玢岩上下盘形成低温低压仓， 因温度梯度及压力梯度形成的热液携带围岩中成矿物质而形成成矿流体，向低温低压仓运移，在运移过程中北西向张扭断裂受区域韧性剪切作用的改造，而表现为韧性剪切带性质，相应地使低温低压仓中的刚性、塑性岩石破碎及糜棱岩化，并形成相应的含金岩系，因此，下大堡金矿床属韧性剪切－ 中温热液蚀变岩型叠加矿床。

ORE CONTROLLING FACTORS OF XIADAPU GOLD DEPOSIT IN QINGYUAN COUNTY AND ORE PROSPECTING DIRECTION IN FUSHUN AREA

The major metallogenetic elements, heat sources of metallogenetic fluid in Xiadapu gold deposit, and relationship of ductile shearing belts with metallogenesis have been studied . The re sults show that after the forming of second order NW trending tenso shearing faults of Xiadapu fault, andesite porphyrite magma intruded in the late stage of Yanshanian period , and then a low temperature and low pressure storehouse formed in the upper and lower sides of the andesite por phyrite vein . After metallogenetic materials in the wall rocks added in the hydrothermal, which resulting from temperature and pressure gradient,the metallogenetic fluid formed and moved to the low temperature and low pressure storehouse. During the movement of fluid, NW trending ten so shearing faults were reformed by a regional ductile shearing and showed ductile shearing behav iors, and at the same time , the rigid and plastic rocks in the low temperature and low pressure storehouse were fractured and mylonized , and then formed gold bearing rock series. So Xiadapu gold deposit is a ductile shearing medium temperature hydrothermal altered rocks type superimposed deposit. The major ore controlling factors are Nankouqian granite orebody providing ore forming material, NW trending ductile shearing belts, Mesozoic fault basin , Late Yanshanian andesite por phyrite , hydrothermal alteration , temperature and pressure lowing areas. On the basis of the ore controlling factors of Xiadapu gold deposit,some gold deposits are forecasted for Fushun area.