辽河东部凹陷滩海地区东营组准层序成因研究及意义

利用钻井及地震资料，详细研究了辽河东部凹陷滩海地区东营组的准层序组和准层序特征，认为该地区东营组包含了陆相准层序的两种基本类型：湖相沉积体制准层序，由向上变粗的沉积序列组成；河流沉积体制准层序，在河流体系分布区为向上变细的正粒序，在泛滥盆地相分布区为向上变粗的反粒序。成因分析表明，东营组准层序的特征和形成受四级构造幕沉降作用控制，从沉积空间演化角度看，准层序边界是一个沉积空间突变面。通过分析沉降速率变化引起沉积空间演变的沉积响应特征，解释了两类准层序的形成过程，并建立了相应的准层序成因模式。提出的认识为陆相断陷盆地准层序划分和对比提供了新的理论依据

A genesis study and significance of parasequence in the Dongying Formation, East Liaohai sag.

Two basic types of parasequence in the continental basin are included in the Dongying Formation, East Liaohai sag. A parasequence deposited in the lacustrine depositional regime comprises coarsening upward succession, while a parasequence in the fluvial depositional regime is fining upward in the fluvial system distribution area and coarsening upward in the flooding basin area. Genesis analysis suggests that the development of parasequences in the Dongying Formation was controlled by the 4th order episodic tectonic subsidence and the boundary of a parasequence is an abrupt accommodation changing surface in a view point of accommodation evolution. Their developing processes have been interpreted through an analysis of deposition response to accommodation variation caused by subsidence velocity changes, and two parasequence genetic models have been established accordingly. The conclusions made by genetic analysis bring new theoretical guides to parasequence division and correlation in the continental rift basin.