苏北盆地高邮凹陷永联地区戴南组沉积相及沉积演化分析

Analysis on sedimentary facies and sedimentary evolution of Dainan Formation in Yongan-Lianmengzhuang Area of Subei Basin

针对永安—联盟庄地区始新统戴南组沉积相及演化特征研究较少的问题,结合钻井、测井、录井及区域地质背景等资料的分析成果,识别主要沉积相类型,概括出沉积演化特征。研究显示,研究区戴南组主要发育三角洲相和湖泊相,细分3种亚相;平面上该区主要发育三角洲前缘和滨浅湖沉积亚相;垂向上,戴一段沉积体系以三角洲—湖泊为主,戴二段沉积体系以河流—三角洲—湖泊相叠置为主;研究区戴南组早期为"深盆浅水"的沉积环境,此后因大规模湖侵而导致湖泊水体扩大,随后地形高差减小,湖盆萎缩,沉积环境变为"广盆、浅盆浅水"。

Taking the Dainan Formation of Eocene in the Yongan-Lianmengzhuang Area as an example,combining with drilling,logging,and other information,the main sedimentary facies types were identified and the deposition patterns were summarized. The results show that the study area is mainly developed lake facies and delta facies,besides five subfacies and eleven microfacies were identified; on the plane,this area mainly developed the delta front and shore shallow lake subfacies; vertically,the E_2d_1 of this area mainly developed delta-lacustrine sedimentary system,the E_2d_2 mainly developed river-delta-lacustrine sedimentary system; the study area experienced the changes of sedimentary environment of ＂ deep basin and shallow water＂, ＂ deep basin and deep water＂ to ＂ wide basin,shallow basin and shallow water＂.