米家山隆—滑构造初析  

PRELIMINARY ANALYSIS ON UPLIFT BEDDING-DELAMINATION STRUCTURE IN MIJIASHAN

作　　者：于福生 王春英 

机构地区：[1]甘肃地勘局区域地质调查队

出　　处：《甘肃地质学报》1997年第2期77-81,共5页Acta Geologica Gansu

摘　　要：米家山隆—滑构造是在古浪运动造山前期伸展体制下形成的。隆—滑构造的内核隆起由顺基底与盖层之间的接合面呈席状同构造侵位的马黄沟梁单元组成。由于花岗岩的局部隆起，在阴沟群变质岩系内多层滑脱型韧变带与流褶层形成的同时，因变形分解作用，导致火山岩透镜体与韧变带及流褶层相间分布的格局。在古浪运动收缩体制下，米家山岩体呈塑性底辟式再就位，从而形成泉沟单元。晚期的祁连运动产生的构造形迹横跨叠加于古浪运动构造形迹之上，最终使米家山深成岩体分布于穹形构造核部。While Mijiashan were still in the tectonic setting of preorogenic extension during Gulang movement, uplift bedding-delamination structure formed. Core of uplift Bedding-delamination structure is composed of the Mahuanggouliang unit emplacing synoptically as sheet along the contact plane between the cover and the basement. Because of granite local uplift,formed ductile shearing belts and the rheid fold layers with the multilayer delamination in metamorphic rocks of Yingou group,at the same time, some large-scale lens of volcanic series distributed between the ductile shearing belts and the rheid fold layers owing to deformation partitioning.During the Shortening stage of Gulang movement Mijiashan rock body granites reemplaced in plastic diapir,so the Quangou unit was formed.The former tectonic patterns during Gulang movement were crossly and over printed by the late Qilian movement,then Mijiashan pluton distributed in the core of dome-shape structure.

关 键 词：米家山 隆-滑构造 伸展机制 滑脱构造 

分 类 号：P542.3[天文地球—构造地质学]