中国东部典型裂谷盆地构造活动特征及演化:以松辽盆地孤店断陷为例

孤店断陷为松辽盆地南部深层天然气勘探的有利区带，同时也记录了中国东部中-新生代板块运动和盆地演化的丰富信息。利用钻测井资料及高分辨率三维地震资料，并结合区域构造背景，对孤店断陷的地质结构及构造演化特征进行分析。结果表明孤店断陷在纵向上可以划分为基底构造层、下构造层、中构造层及上构造层。由于受到晚中生代以来太平洋板块向东亚板块的俯冲作用及区域构造应力场的影响，孤店断陷的构造演化过程可以划分为断陷期、断坳转换期、稳定坳陷期及构造反转期。孤店断陷的边界大断层(孤店断层)在断陷初始发育期(火石岭组-沙河子沉积期)表现为6段走向各不相同的小型孤立断层，在断陷晚期(营城组沉积期)经过生长、连接而形成统一的断陷边界，并在断坳转换期(登娄库组-泉头组沉积期)和坳陷期(青山口组-嫩江组沉积期)发生广泛而强烈的张扭活动，以及在构造反转期(嫩江组沉积末期)发生强烈反转和分段差异逆冲活动。研究结果可以为松辽盆地以及中国东部地区的构造活动及演化研究提供参考，并进一步指导油气勘探。

Tectonic characteristics and evolution of typical rift basins in eastern China: A case study in the Gudian area,Songliao Basin

The Gudian Rift is a favorable area for deep natural gas exploration in the southern Songliao Basin, and it also records rich information on basin evolution and Mesozoic-Cenozoic plate movements in eastern China.By using the well and high-resolution 3D seismic data, combined with regional tectonics, the geological structure and tectonic evolution of the Gudian Rift were investigated.The results show that the Gudian Rift can be vertically divided into basement, lower, middle and upper structure layers.Due to the subduction of the Pacific Plate beneath to the East Asian Plate and the changes in the regional tectonic stress field since the Late Mesozoic, the Gudian Rift experienced syn-rift, transition, post rift and tectonic inversion periods.The Gudian fault was initially formed from six fault segments in syn rift period(depositional period of the Huoshiling and Shahezi Formations) and the isolated fault segments with different strikes then grew and connected to a unified boundary fault in the late rifting stage(depositional period of the Yingcheng Formation).Afterwards, extensive and intense transtensional activities occurred during transition(depositional period of the Denglouku and Quantou Formations) and depression periods(depositional period of the Qingshankou, Yaojia and Nenjiang Formations), and strong inversion and segmental thrust activities occurred during inversion period(end of the depositional period of the Nenjiang Formation), respectively.This study provides references for the investigation of tectonic activity and evolution in the Songliao Basin and eastern China, and further guides oil and gas exploration.