塔中奥陶系大型不整合面与风化壳岩溶发育

塔里木盆地经历了多期构造运动,造成沉积间断,继而形成一系列重大的地层不整合面.塔中地区奥陶系主要发育有两个大型的不整合面T47和T07,它们受构造和海平面的共同控制,暴露时间长,规模大,在区域上控制了两期强烈的风化壳岩溶事件的发育.第一期位于下奥陶统顶部不整合面之下,第二期位于上奥陶统顶部不整合面之下.这两期岩溶特征因其上覆不整合面的特征不同而不同.不整合面对岩溶发育的控制主要体现在两个方面,一是不整合面形态对分化壳岩溶发育范围的控制,二是不整合面的强度级别对分化壳岩溶发育深度的控制.

Relationship Between Large Scale Unconformity Surface and Weathering Crust Karst of Ordovician in Tazhong

The Tarim basin has experienced periods of structure movements and developed a series of large stratigraphic unconformities.The Ordovician has two large unconformity surfaces T47 and T67 in central of Tarim,which are predominated by structure movements and sea level changes.Being exposed for a long time,the development of two periods regolith karst is locally controlled.The first period karst locates under the unconformity top of down-Ordovician,the second locates under the unconformity top of up-Ordovician.The character of two periods' darst are different for their different unconformities.The effects of the unconformity surface on karst mainly include two aspects:one is the configuration of unconformities which controls the development scale of regolith karst,another is the intensity of unconformities which controls the development depth of regolith karst.