依-舒地堑方正断陷古近系构造演化与沉积相带展布特征  

Paleogene structural evolution and distribution characteristics of sedimentary facies in the Fangzheng fault depression of the Yishu graben

作　　者：何星[1] 杨建国[1] 李映雁[2] 

机构地区：[1]大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [2]中国地质大学,湖北武汉430074

出　　处：《中国地质》2008年第5期902-910,共9页Geology in China

基　　金：全国油气资源战略选区调查与评价项目(XQ-2004-02)资助

摘　　要：方正断陷由南向北划分为南部斜坡、南部凹陷、中部凸起、北部凹陷和北部斜坡共5个二级构造单元。古近系是方正断陷形成、发育、演化的主要阶段,乌云组和新安村组沉积时期为强烈断陷期,达连河组沉积时期为持续断陷期,宝泉岭组一段沉积时期为断凹转化期,宝泉岭组二段沉积时期为断陷萎缩期。乌云—新安村组和宝二段沉积时期,盆地总体构成了水系发育的扇三角洲-滨浅湖沉积体系;达连河组和宝一段沉积时期,盆地总体构成了横向水系发育的扇三角洲-半深湖沉积体系。从乌云—新安村组到宝泉岭组二段,沉积中心由北到南再到北,湖泊面积由小变大再到小,湖泊水体由浅变深再变浅。The Fangzheng fault depression can be divided into five second-order structural units from south to north; they are the southern slope, southern subdepression, central rise, northern subdepression and northern slope. The Paleogene System was the main phase of formation, development and evolution of the Fangzheng fault depression. The period of deposition of the Wuyun and Xin＇ancun formations was an intense fault downfauting period. The period of deposition of the Dalianhe Formation was a continued downfaulting period. The period of deposition of the First Member of the Baoquanling Formation was a period of transformation for downfaulting to downwarping, and the period of deposition of the Second Member of the Baoquanling Formation was a period of shrinking of the Fault depression. In the period of deposition of the Wuyun-Xinancun Formation and the Second Member of the Baoquanling Formation, a fan delta-lakeshore and shallow lake deposition system developed by the drainage system in the basin. In the period of deposition of the Dalianhe Formation and the First Member of the Baoquanling Formation, in the basin there occurred a fan delta to semi-deep lake deposition system, in which a horizontal water system was developed. From the Wuyun-Xinancun Formation to the Second Member of the Baoquanling Formation, the depocenter migrated from north to south and then again to the north, and simultaneously the large lake area became small and again became large and the shallow lake became deep and then again became shallow.

关 键 词：方正断陷 古近系 沉积相 构造演化 沉积中心 

分 类 号：P542.3[天文地球—构造地质学]