【摘要】 辽北清河镇群是由一套蛇绿岩组成,其中硅质岩与绿片岩和碳酸盐岩密切共生。在硅质岩中釆到了下古生代化石,从而否定了辽北“辽河群”的存在。根据硅质岩的化学成分关系图解和硅质岩的平均原子量计算,以及与硅质岩共生的岩石组合等分析, 笔者认为清河镇群中硅质岩形成于深海平原,硅质来源于地壳深部,通过生物比学作用而沉积,属于大洋板块内部远海沉积的硅质岩,随着大洋板块的俯冲作用被带到俯冲带中残留下来。更多还原

【Abstract】 Qinghezhen Group consists oi a suite of ophiolite. The siliceous rocks associate with green schists and carbonatite in the area. The fossils of lower paleozoic have been founed from the siliceous rock and carbonatite. It lays a firm foundation for discarding Liaobei-Liaohe Group and setting up Qinghezhen Group.According to the chemical illustration and the average atomic weight of siliceous rocks and their rock assemblage, the writer considered that Qinghezhen Group was formed in pelagic-abyssal plain, and siliceous sediments was derived from deep crust and sedimented by bio-chemical precipitation. It belonged to abyssal sediments within oceanic plate. With the subducting of oceanic plate, the siliceous rocks have been brought to subduction zone and left over there更多还原