辽宁省开原市八棵树一带地质构造特征

Bakeshu geological structural characteristics of Kaiyuan City,Liaoning Province

辽宁省开原市八棵树一带在晚三叠世之前横跨两大地质构造单元,二者大致以八棵树—大孤家断裂(即清河断裂)为界,南部为龙岗复合陆块,北部为其陆缘活动带,两区分别经历了不同的地质构造发展阶段,龙岗复合陆块经历太古宙陆核的形成及发民阶段和元古宙盖层形成及发展阶段,北部陆缘活动带经历元古宙—早三叠世古亚洲构造域发展阶段,晚三叠世开始两区共同进入滨太平洋构造域发展阶段。区内发育不同构造发展阶段形成的褶皱构造、变质变形构造、韧性剪切带构造、逆冲推覆构造及脆性断裂构造。

Kaiyuan of Liaoning Provinc across the two geological units before the Late Triassic,roughly Bakeshu-Dagujia fracture（ie,Qinghe fault） as the boundary,the southern part is the Longgang compound land mass,the northern part is epiconyinental activities,they underwent different stages of geological development respectively,Longgang composite land mass underwent Archean continental nucleus formation and development stage,Proterozoic superficial formation and development stage;the northern epiconyinental activities underwent the Proterozoic-Early Triassic Paleo-Asian tectonic developmental stages,in late Triassic,the two areas together enter into marginal-Pacific tectonic domain developmental stages.There developed fold structure,metamorphism and deformation structure,ductile shear zone structure,thrust nappe structure and brittle fault structure in different developmental stages.