山东西涝口金矿床控矿构造特征及动力学浅析

西涝口金矿床位于胶莱盆地北缘,区内盆缘断裂发育,控矿构造主要为近EW向压扭性断裂和NE向滑脱构造。控矿断裂构造形成受中国东部晚中生代构造体制转换过程动力学背景制约,在晚侏罗世太平洋板块、库拉板块向欧亚大陆俯冲的侧向应力挤压作用下,牟平-即墨断裂带发生显著的左旋走滑活动,矿区近EW向断裂构造形成,后期受拉张活动而呈张性容矿构造。NE向断裂构造则形成于早白垩世时期构造体制以引张伸展活动为主的大地构造环境,并在成矿过程中起着重要控矿作用。

Primary Study on OreControlling Structures Characteristicsand Dynamics of Xilaokou Gold Deposit in Shandong Province

Xilaokou gold deposit is located in the northern margin of Jiaolai basin. The basinmarginal faults developed well in this area. The ore controlling structures are mainly essional torsional faults with the trend of EW and decollement structures with the trend of NE. The formation of ore controlling faults is controlled by dynamics background during the transformation of late Mesozoic tectonic regime. Under the compression of horizontal stress of the subduction from late Jurassic Pacific plate, Kula plate toEurasian plate, obvious sinistral strike slip occurred in Muping Jimo fault zone. Fault structures with the trend of EW has been formed in the mine. In the late period, due to tensioned activities, it showed as a tensional ore hosting structure. The fault structure with the trend of NE is formed in tectonic environment of extensional activity during the early Cretaceous tectonic system. It plays an important ore controlling role in the mineralization process.