依兰地区黑龙江增生杂岩中变质硅质岩的地球化学特征及大地构造背景

Geochemical characteristics and tectonic settings of metamorphic siliceous rock in Heilongjiang accretionary complexes,Yilan area

出露于黑龙江省依兰县境内的黑龙江增生杂岩中的变质硅质岩野外露头主要表现为大小不一的构造岩块或岩片,大者呈岩块夹于长英质片岩中,小者呈岩片或布丁夹于大理岩或绿片岩中,变质硅质岩块体长轴方向与大理岩、绿片岩片理方向一致,与大理岩、绿片岩以构造接触为特征。对出露于黑龙江省依兰县境内的黑龙江增生杂岩中的变质硅质岩进行地球化学特征研究后发现,该地区变质硅质岩形成于近大陆边缘区较深的洋盆环境。

The outcrops of metamorphic siliceous rocks in Heilongjiang accretionary complexes,Yilan area are like tectonic slice or block.They are not of uniform size,the big size are distributed in felsic schist as blocks,the small size are chaotically distributed in the marble and green schist as sheets or boudins.The major axis direction of metamorphic siliceous rock are similar with orientation of schistosity in marble and green schist,and they demonstrated as tectonic contact.Through geochemical analysis of metamorphic siliceous rocks in Heilongjiang accretionary complexes,Yilan area,we discovered that metamorphic siliceous rocks in this area maybe formed in relatively deep ocean basin environment which is near to continental margin.