辽东湾坳陷旅大地区东营组三角洲沉积体系及沉积相模式

Delta Sedimentary System and Facies Model of Dongying Formation in Lvda Area of Liaodongwan Depression

三角洲是辽东湾旅大地区东营组最为发育的沉积相类型,遍布发育于东一段到东三段。根据单井沉积相,连井沉积相,地震相特征,确定了旅大地区东营组各亚段沉积相平面展布,绘制了东营组各亚段的沉积相分布图。研究表明,旅大地区主要分布于在辽西凹陷,辽中凹陷,辽东凹陷区,东营组存在三角洲沉积体系发育条件。亦即较高的成分成熟度反映了物源经过充分的分选,三角洲的相标志反映以牵引流为主沉积特征,地震剖面上具有三角洲地震相典型的三层结构特征。对东营组三角洲相分析,共划分为三角洲平原,三角洲前缘,前三角洲三个亚相及相应微相,并建立旅大地区东营组三角洲沉积相模式,从沉积相的角度为油气勘探提供指导依据。

The delta is the most developed sedimentary facies type, widely ranging in Ed-1 to Ed-3 sections in Lvda area of Liaodong Bay. Based on single well sedimentary facies, multiple-well sedimentary facies and seismic facies characteristics, the planar distribution of subsegmental sedimentary facies was determined,and distribution map of sedimentary facies of Dongying formation in Lvda area was drawn. The results show that Lvda district mainly distributes in Liaoxi,Liaozhong and Liaodong depressions. Thus there is condition of delta development in Dongying formation. The high compositional maturity reflects sufficient separation of provenance. Delta facies mark mainly reflects traction current sedimentary characteristics and typical three-layer structure of delta seismic facies in seismic profile. The delta facies in Dongying formation was analyzed, and it was divided into delta plain,delta front and prodelta three subphase and corresponding micro facies.At last, the delta sedimentary facies model of Dongying formation was established, which could provide guidance for oil and gas exploration.