松辽盆地北部断裂演化序列与反转构造带形成机制  

Evolutionary sequence of faults and the formation of inversion structural belts in the northern Songliao Basin

作　　者：孙永河[1] 陈艺博[1] 孙继刚[2] 付晓飞[1] 胡明[1] 

机构地区：[1]东北石油大学地球科学学院 [2]大庆油田有限责任公司第四采油厂地质大队

出　　处：《石油勘探与开发》2013年第3期275-283,共9页Petroleum Exploration and Development

基　　金：国家自然基金项目(41072163);高等学校博士学科点专项科研基金(20112322120002)

摘　　要：立足松辽盆地北部区域地震解释,从分析断裂几何学特征着手,以断裂形成演化过程为主线,系统剖析了盆地演化不同阶段断裂的变形机制,揭示了反转构造带的形成机制及其对油气运聚成藏的指示作用。研究表明,松辽盆地北部断裂演化经历了断陷期的持续伸展变形、拗陷期的持续张扭变形和反转期的连续挤压构造反转变形。盆地晚期构造反转变形是在基底深大断裂、断陷期北西—南东向引张应力场形成的半地堑以及拗陷期近东西向拉张应力场形成的多方位断裂密集带基础上开始演化的。反转期左旋压扭变形场与断陷半地堑、基底深大断裂共同控制了次级背斜带和反转构造带的形成,大庆长垣地区受北北东向断陷半地堑和北北东向基底深大断裂双重影响,反转程度最大,将反转期初始北东向的次级背斜带最终连成北北东向的反转构造带,同时将拗陷期形成的以近南北向为主体的断裂密集带旋转改造成以北西—北北西向为主体的断裂密集带展布格局。On the basis of regional seismic interpretation of the northern Songliao Basin and the analysis of fault geometry characteristics and the formation and evolution of faults, this paper analyses fault deformation mechanisms at different stages, which reveal the formation mechanism of inversion structures and their role for oil and gas migration and accumulation. Studies show that the faults in the northern Songliao Basin have experienced the following stages of evolution： a continued extensional deformation in the faulted phase, continuous transtensional deformation in the depression phase and continuous extrusion inversion tectonic de^brmation in the inversion phase. The late tectonic inversion and deformation evolved on the basis of huge rifts in the basement of the Songliao Basin, grabens formed in a NW-SE tensile stress field during the faulted period, and multi-orientation fault-dense zones formed in a nearly EW tension stress field during the depression period. The sinistral compresso-shear deformation field, half grabens and huge basal faults jointly control the formation of subprime anticlines and inversion structural belts during the reversal period. The Daqing placanticline area is controlled by both the NNE half grabens and NNE huge basal faults, so that it has a high reversal degree, which turns NE subprime anticlines into NNE structural inversion belts. Meanwhile, it turns fault dense zones from nearly SN into NW-NNW.

关 键 词：断裂演化 断陷构造格局 断裂密集带 反转构造带 形成机制 松辽盆地北部 

分 类 号：TE122.2[石油与天然气工程—油气勘探]