塔里木盆地博孜—大北地区被动走滑构造特征及其对裂缝发育的控制作用

Characteristics of passive strike-slip structure and its control effect on fracture development in Bozi-Dabei area， Tarim Basin

郭宏辉 冯建伟 赵力彬

Honghui GUO Jianwei FENG Libin ZHAO

库车坳陷位于南天山山前，受多期造山作用、基底先存构造与盐构造等因素的影响，构造格局复杂。明确此类复杂构造系统对裂缝发育的控制作用，对天然气勘探开发具有重要意义。基于前人的研究成果，结合最新地震、露头调查、成像与岩心资料等，系统性总结分析了博孜—大北地区构造模式及裂缝分布特征。研究结果表明，新生代以来研究区在天山造山运动与塔里木板块旋转联合控制作用下，构造系统在冲断的基础上发生被动走滑；在多条NEE向逆冲断层控制下，研究区构造体系南北方向上具有显著差异，呈现明显的分带特征；在走滑调节构造控制下，东西方向上走滑与逆冲相互转化，呈现明显的构造分段特征；断层被动走滑是有效缝发育的主控因素，断层走滑扰动应力场控制下的裂缝发育呈现分带特征；断层走滑作用下形成的断-缝系统是提高井产能的关键。此外，探讨了博孜—大北地区被动走滑构造控制下的裂缝发育规律及井产能特征，为裂缝发育机理的进一步研究提供了基础，同时也为此类油气田勘探开发提供一定的参考。

The Kuqa Depression is of complex structural pattern under multi-stage orogeny， basal pre-existing structure and salt structure in the Meso-Cenozoic South Tianshan Mountains. It is of great significance to clarifying the control effect of such complex structural systems on fracture development. Based on the research results of predecessors， combined with the latest seismic data， outcrop survey， imaging data and core data， we systematically summarize and analyze the structural pattern and fracture distribution characteristics of the Bozi-Dabei area. The results show that since the Cenozoic， under the joint control of the orogeny of the Tianshan Mountains and the rotation of the Tarim plate， the structural system has passively slipped after thrusting. Under the control of multiple NEE-trending thrust faults， the structural system in the study area shows significant differences from south to north， showing obvious zonation； and under the control of the strike-slip adjustment structure， the strike-slip and thrust structures occur alternatively from east to west， showing obvious structural segmentation. Passive fault strike-slipping serves as the main factor controlling effective fracture development， resulting in zonation of fracture development under the control of strike-slip fault disturbance stress field. The fault-fracture system formed by the action of fault strike-slipping is key to increasing well productivity. This study discusses the fracture development pattern and well productivity characteristics under the control of passive strike-slip structure in the Bozi-Dabei area， which is of a basis to further research on the fracture development mechanism and of certain referential significance to the exploration and development of similar oil and gas fields.

10.11743/ogg20230413