北秦岭前寒武纪地壳组成及其构造演化

北秦岭主要发育元古宙构造岩石地层单位，包括古元古代秦岭岩群、中元古代峡河岩群、宽坪岩群和武关岩群、中元古代晚期松树为蛇绿岩构造岩片、新元古代丹凤岩群和二郎坪岩群的下部地层单位以及晋宁期强烈的构造岩浆活动。北秦岭广泛存在晋宁期的强烈构造-岩浆-变质地质事件，且是新元古代主体形成的古老造山带。晋宁期的强烈地质事件可能代表了华北地块、北秦岭微地块、中秦岭地块与扬子地块之间的俯冲碰撞拼合。震旦纪之后又逐渐开始发生大陆裂解，进入显生宙构造演化阶段。新元古代晋宁期（1000～800Ma）发生的主要地质事件和俯冲-碰撞拼合与国外一些地质学家提出的新元古代时期Rodinia超大陆的形成不谋而合。

CRUSTAL COMPOSITION AND TECTONIC EVOLUTION OF THE NORTH QINLING OROGENIC BELT

The North Qinling orogenic belt is mainly composed of Proterosoic tectonolithostratigraphic units including Qinling group in Pa1aproterozoic, Xiahe group,Kuanping group and Wuguan group in Mesproterozoic, Songshugou Ophiolite tectonic slice inlate period of Mesoproterosoic, Danfeng group and lower part lithostratigraphic units ofErlangping group in Neoproterosoic, and tectonomagmatic intrusive rock. The Jinning periodstrong tectono - rnagTnatic - metwhic geological events existed widespreadly on the NorthQinling orogenic belt whose rnain they was an ancient orogenic belt formed duringNeOProterozoic. The Jinning peried strong goolDgical events could indicate subducti0n - collisionmatching between the North China bfork, the N0rth Qinling hacro - bfork, the Middle Qinlingmicro - bl0ck and YangtZe bfork. After Sinian peried, the Qinling rigion began occuringcontinent break - up and entering Phanerozoic tectonic evolution stag6- The Jindng peri0d (1OO0~ 800 Ma) rnain goological events and subduction - collision rnatching to take place in the Qinlingorogenic belt happen to coincide with the formation of the Rodinia supercontinent duringNaproterozoic by some goologists from abmed.