梨树断陷西丁家地区沙河子组—营城组沉积体系及演化过程研究

根据岩心、测录井、地震以及分析化验资料,运用沉积学原理和方法,对西丁家地区沙河子组—营城组时期沉积相和沉积体系进行综合研究。研究表明该区域在早白垩世主要发育湖泊、辫状河三角洲相等四大类沉积相及其亚相和微相。结合研究区＂西断东超＂型箕状断陷的构造演化特征,在沉积相认识的基础上组合出两大类沉积体系：从沙河子组沉积期至营城组沉积期,北部斜坡带由扇三角洲—水下扇沉积体系演化为辫状河三角洲—湖泊沉积体系;西部断阶带主要发育扇三角洲—水下扇沉积体系。

Research on Depositional System and Evolution of Shahezi-Yingcheng Formation in Lishu Fault Depression of Xidingjia Region

According to the core,test logging,seismic testing and analysis of data,by using sedimentary principles and methods,the depositional facies and depositional systems of Shahezi-Yingcheng Formation in Xidingjia region are studied synthetically.The research shows that there are four main types of developed sedimentary facies,sedimentary microfacies and subfacies in this area including lake,braided river delta etc during the early Cretaceous period.By analyzing structural evolution feature of the fault depression which is ＂breaking east overlapping West＂,and combining the understanding of sedimentary facies,two types of depositional systems are summarized.One is from Shahezi to Yingcheng formation deposition period,it is fan delta-submarine fan depositional system evolved into braided river delta-lake system in northern slope.The other is that fan delta-submarine fan depositional systems is mainly developed in west fault zone.