辽中凹陷中北段重力流发育模式与控制因素

Depositional model and controlling factors of sedimentary gravity flows in the central-northern Liaozhong sag,China

辽中凹陷中北段东营组发育多种类型的重力流沉积,它们在形成机制上差别较大。在古地貌恢复的基础上,重建了古地理背景,构建了各沉积时期基本的物源系统和构造格架。通过层序地层研究及物源供给系统分析,明确了重力流的沉积类型、层序位置、发育部位和形成机制,建立了三角洲滑塌浊积扇、坡移浊积扇、近岸水下扇、湖底扇和斜坡扇共五种类型的重力流发育模式。通过沉积要素比较分析,提出了上述重力流的发育是物源系统、坡折类型和湖平面变化耦合作用的结果,辽东凸起的形成演化及以其为主导的构造格局决定着重力流的发育特征及分布规律。

There are several types of sedimentary gravity fl the central-northern Liaozhong sag. According to the pala ows of Pa eogeograp leogene Dongying Formation in hic background analysis on the basis of palaeogeomorphology, the authors reconstruct the provenance system and the structural framework of study area. After studying the sequence stratigraphy and the provenance system, they definite the sedimentary type, sequence position, depositional area and formation mechanism of the gravity flows and set up the depositional models of turbidity fan, nearshore subaqueous fans, sublacustr difference of sedimentary elements, they sum up that se of provenance system, slop type a structural framework of the Liao the delta slump turbidite fan, slop-moving lne dim nd lake level fluctuati fan and slope fan. After entary gravity flows are the on and that the evolution analyzing the co an uping result d dominant dong lift control the sedimentary character and distribution characteristics of the gravity flows.