滇西北羊拉铜矿区地层划分

通过滇西北羊拉矿区7.5km实测地层剖面的岩石地层划分，矿区原定二叠纪嘎金雪山群巨厚洋盆沉积实际由泥盆纪至二叠纪构造岩块高度混杂而成。因矿区经历了金沙江洋盆的初始裂开、扩张、俯冲消减、碰撞造山的洋－陆转换过程，岩石普遍发生绿片岩相变质作用，缺少古生物化石，原岩层序难以恢复。基于前人成果和本次工作发现的牙形石，结合矿区沉积特征和金沙江洋演化历史，将地层修订为下泥盆统江边组岩块、中泥盆统－石炭系岩块、二叠系岩块，并讨论了其构造演化。

STRATIGRAPHIC SUBDIVISION IN YANGLA COPPER OREFIELD, NORTHWESTERN YUNNAN

Base upon a 7.5km measured geological profile across Yangla mining area and lithostratigraphic subdivision, the stratum of Yangla mining area called Gajinxueshan Group, which thought to be gigantic and thick sediments of oceanic basin in Permian, now proved to be consists of tectonic malange from Devonian to Permian. For reasons that initial cracking, oceanic spreading, oceanic subduction, and collision orogency that Yangla area experienced, the greenschist facies metamorphism which rocks widely underwent and the lack of ancient-life fossils, the reconstruction of protoliths and strata sequence is intangible. On the basis of research of predecessors and our discovery of conodonts, considering Sedimental features and evolutionary history of Jinshajiang ocean, we subdivide the strata into Early Devonian Jiangbian Formation rock massif, Middle Devonian-Carboniferous rock massif and Permian rock massif and we discussed its tectonic evolution.