长武地区延长组层序地层划分与含油气特征

Strata Sequence Divisions and Hydrocarbon-bearing Characteristics of Yanchang Formation in Changwu Region

根据层序地层学原理,应用取岩芯、录井和测井等资料,对延长组地层层序进行划分,可将其划分成三个三级层序:即SⅢ1,SⅢ2,SⅢ3,每个层序又包括三个体系域:即低位体系域、湖侵体系域和高位体系域。研究结果表明:层序对含油气特征的控制主要表现在三个方面:1)层序控制了生储盖的组合;2)层序控制着储层的展布;3)层序影响着储层的储集性能,综合反映出延长组含油气特征。

According to the Principles of sequence stratigraphy, by means of some data of coring, drilling log and well logging, we make classification and contrast on the strata sequence of Yanchang Formation and divide it into three sequences（SⅢ1, SⅢ2 and SⅢ3） and every strata sequence contains three systematic ranges： Low-water Level Systematic range, Lacustrine Transgressive Systematic range, and High--water Level Systematic range. The research shows that 1）the sequence controls the combination of oil bearing,.accumulation and covering; 2）the sequence controls the distribution of the reservoirs; and 3 ） the sequence influences some accumulative properties of the reservoirs and synthetically reflects some hydrocarbon--beating characteristics of Yanchang Formation.