塔里木盆地顺托果勒低隆及邻区加里东中期运动面的构造性质

顺托果勒低隆及邻区加里东中期运动面的结构特征、区域分布规律及其构造性质具有重要的研究意义。本文运用钻井资料分析、地震资料解释等对研究区加里东中期运动面进行研究，结果表明：1）研究区加里东中期3个幕次的构造运动导致3个运动面的形成：Ⅰ幕运动面由塔中地区的O₃l/前O₃l角度不整合面、顺托果勒到塔北地区的O₃q/O₂yj平行不整合面组成，Ⅱ幕运动面为O₃s （或O₃qr）与下伏碳酸盐岩构成的同构造沉积超覆型角度不整合面，Ⅲ幕运动面为S/O角度不整合面，在隆起区存在显著的构造削截特征。2）3个运动面的结构特征和差异分布规律具有明确的构造指示意义：Ⅰ幕、Ⅲ幕运动面属于典型的构造成因不整合面，形成于周缘洋盆关闭、陆块碰撞造山时期；Ⅱ幕运动面的形成则受到早期构造格局、全球海平面上升及盆地南缘碰撞造山作用的综合控制。3）顺北、顺南地区地震剖面中存在沿鹰四段顶面以下顺层规律分布的“串珠”反射，推测属于准同生岩溶洞穴。

Structural properties of the Mid-Caledonian Movement surfaces in the Shuntuoguole lower uplift and adjacent area,Tarim Basin

For the Mid-Caledonian Movement surfaces in the Shuntuoguole lower uplift and adjacent area, it is of great significance to study their structure, regional distribution and structural properties. Drilling data analysis and seismic interpretation are applied to research these Mid-Caledonian Movement surfaces, and the result shows that：1） the Mid-Caledonian Movement of the research area can be divided into three episodes, which result in the formation of three tectonic surfaces, or unconformities. Tectonic surfaces formed in the episode Ⅰ include the O₃l/AnO₃l angle unconformity surface distributing in the Tazhong area, and the O₃q/O₂yj parallel unconformity surface distributing in the Shuntuoguole lower uplift and Tabei uplift. Surfaces formed in the episode Ⅱ is a syn-tectonic and sedimentary overlapping unconformity existed between the O₃s （or O₃qr） and underlying carbonate strata. The unconformity of episode Ⅲ is S/O angle unconformity, there is evident tectonic truncation structure in the Tabei uplift and Tazhong uplift. 2） The above unconformities has clear structural significance：tectonic surfaces formed in the episode Ⅰ and episode Ⅲ are typical tectono-genetic unconformity, formed in the closing period of surrounding oceans and the period of continental collision and orogeny; while, the formation of the episode Ⅱ surface is controlled by the former tectonic framework, global sea level fluctuation and the continental collision and orogeny in south of the basin. 3） “Beading” reflections are recognized in the Shunbei and Shunnan area, it is inferred that they were karst cave formed in the pene-contemporaneous karstification.