论东秦岭前寒武纪的构造演化特征

本文研究的范围主要涉及东秦岭的北部地区——北秦岭(即旧称“秦岭地轴”)。作者着重讨论了秦岭造山带的杂岩(秦岭杂岩、宽坪杂岩和陶湾杂岩)和太华杂岩的岩石组合、原岩建造、岩石化学、地球化学技其地质构造特征。提出秦岭杂岩是在中元古代时期因华南洋壳海域的岩石圈断块沿华北断块南缘向北俯冲引起断块区基底开裂,向南漂离而形成的块体。宽坪杂岩与陶湾杂岩是在秦岭杂岩块体向南漂离过程中形成的以洋壳为底的边缘海盆地的产物。经晋宁运动,边缘海闭合,形成早期的北秦岭造山带。

ON THE CHARACTERISTICS OF PRECAMBRIAN STRUCT UR-AL EVOLUTION OF THE EAST QINLING MOUNTAIN

The range of study in this thesis involves mainly the northern area of the East Qinling Mountain (i.e. it was called the Earth's Axis in the past). The Authors have discussed mainly the characteristics of rock assemblage, primary rock formation, petrochemistry, geochemistry and their structures from the Qinling complex and Taihua complex. We have proposed that the Qinling complex was the block derived from the crystalline basement of North China Fault Block, owing to subdution of the lithosphere fault-block of South China with oceanic crystal sea areas beneath the south margin of North China Fault Block in Middle Proterozoic era.Kuanping complex and Taowan complex were products of the marginal-sea basin with oceanic crust at it's base, which formed in process of southward drifting of the Qinling complex block. The marginal-sea basin was closed after Jinning movement. Then the early orogenic belt of North Qinling formed.