Structural characteristics of the basement and the prospective of favorable oil and gas blocks in the Tacheng basin

The Tacheng basin has been identified as a Carboniferous basement with a central uplift, sur- rounded by orogenic belts. This identification was based on the comprehensive analysis of field outcrops, regional magnetic and gravimetric data, skeleton seismic profiles, magnetotelluric profiles and drilling data. Here, we present gravimetric and magnetic data analyses of the basement structures of the Tacheng basin and its base formation. We also provide a magnetotelluric profile analysis of the structural features and tectonic framework of basin-mountain patterns. We use local geology, drilling data, and other comprehensive information to document the tectonic framework of the basement of the basin. Small-scale nappe structures are found in the northern basin, whereas stronger and more pronounced thrusting structures are found to the south and east of the basin. The basin is divided into four first-order tectonic units： a central uplift, a northern depression, a southeastern depression and a western depression. In addition, the Emin sag is suggested as a possible reservoir for oil and gas.

中国地壳结构构造与形成过程:来自构造变形的约束

中国地壳结构构造与形成过程,一直是地质界关注的重大地质构造问题。然而已有研究主要侧重于构造单元划分和构造演化,而对各个构造单元构造变形以及相互之间的构造关系,没有给予足够重视。文章基于对已有资料的综合研究和笔者研究积累,分析和总结了华南、华北、东北、西北、青藏高原和苏鲁—大别—秦岭等地区的构造变形特征与地壳结构构造,根据构造变形特征,结合其他方面的资料,提出松辽盆地两侧构造单元可以对比连接,东准噶尔与西准噶尔以及东天山与西天山构造单元分别属于不同古陆的增生边缘不应该对比连接,牡丹江缝合带不存在,以及中国东部发育两个方向的隆起-坳陷构造等新认识。基于不同时代构造变形特征,对华北古陆基底结构和形成时代、塔里木和扬子古陆基底形成时代、古生代至三叠纪中国大陆主体聚合过程以及侏罗纪以来中国东部构造变形对已有构造的叠加改造和现今中国地壳结构构造最终形成,进行了初步讨论。