依—舒地堑方正断陷古近系构造演化与沉积相带展布特征

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。

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

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 downfault...