石油学报 ›› 2012, Vol. 33 ›› Issue (2): 204-212.DOI: 10.7623/syxb201202004

• 地质勘探 • 上一篇    下一篇

渤海西部沙垒田凸起区走滑断层演化及其对油气的控制作用

彭文绪 1,2 张志强 2 姜利群 2 石文龙 2 陈国童 2   

  1. 1同济大学海洋与地球科学学院 上海 200092;2中海油渤海油田勘探开发研究院 天津 300452
  • 收稿日期:2011-09-11 修回日期:2012-01-09 出版日期:2012-03-25 发布日期:2012-05-17
  • 通讯作者: 彭文绪
  • 作者简介:彭文绪,男,1972年9月生,1998年毕业于中国石油大学(北京),现为同济大学海洋与地球科学学院在读博士研究生、中海油渤海油田勘探开发研究院高级工程师,主要从事油气勘探研究。
  • 基金资助:

    国家重大科技专项“近海大中型油气田形成条件及勘探技术”(2008ZX05023)资助。

Evolution of strike-slip faults in the Shaleitian bulge of the western Bohai offshore and their control on hydrocarbons

PENG Wenxu 1,2 ZHANG Zhiqiang 2 JIANG Liqun 2 SHI Wenlong 2 CHEN Guotong 2   

  • Received:2011-09-11 Revised:2012-01-09 Online:2012-03-25 Published:2012-05-17

摘要:

渤海海域西部沙垒田凸起区潜山为太古界花岗岩,新近系河流相碎屑岩直接覆盖在基底潜山之上。该区发育长约20 km的NE向右旋走滑断层,斜切整个凸起。潜山内发育的NE和NW向两组走滑断层走向夹角约100°,NE向主走滑断层持续活动至今;NW向断层延续较短,局部表现为沟道,新近纪停止活动。该区走滑断层整体表现为负花状构造。新近纪构造运动在主走滑断层附近诱发大量近EW向左旋张扭性小断层并对主走滑断层形成切割。高分辨率三维地震资料精细解释表明,该区断层演化经历了三个阶段,即新近纪前基底断裂走滑阶段、新近纪早期盖层张性断裂弱雁列化阶段、新近纪晚期盖层张扭性断裂强雁列化阶段。凸起区走滑断层的多期活动不仅形成了断背斜圈闭,而且控制了走滑断层两盘古近系的沉积,对油气聚集和重新分配产生影响。

关键词: 走滑断层, 花状构造, 沙垒田凸起, 渤海湾盆地

Abstract:

Buried hills in the Shaleitian bulge of the western Bohai offshore are composed of Archaeozoic granite, which is immediately covered by Neogene fluvial clasolites. In this area there is a well-developed NE dextral strike-slip fault that stretches for about 20km and slantingly cuts through the whole Shaleitian bulge. The angle between the NE and NW strike-slip faults within the buried hills is about 100°. The major NE strike-slip fault keeps unceasingly active, while NW faults being no longer active in Neogene extend discontinuously with partial segments displayed as channels. Strike-slip faults in this area commonly show a minus flower structure and the Neogene tectonic movement induced numerous approximately-EW dextral extensional minor faults near the major strike-slip fault, which cut the major strike-slip fault occasionally. Based on detailed interpretations of high-resolution seismic data, we divided the evolution of faults in this area into three stages: the formation of base strike-slip faults in pre-Neogene, the formation of feebly-en-echelon faults in cover strata in early Neogene and the formation of tenso-shear and strongly-en-echelon faults in cover strata in late Neogene. Multiperiodic activities of strike-slip faults in the uplifted area not only formed faulted-anticline traps but also controlled Paleogene deposits on both sides of the faults, exerting an influence on the accumulation and redistribution of hydrocarbons.

Key words: strike-slip fault, flower structure, Shaleitian Bulge, Bohai Bay Basin