扇三角洲高精度层序地层及其与油气聚集关系——以东营凹陷胜北断层下降盘坨76块为例

本文通过地质、地震、测井等资料,对东营凹陷胜北断层下降盘坨76块沙四上亚段扇三角洲沉积体层序地层单元进行了精确划分对比,将其划分为4个准层序、18个层组和29个单层。在扇三角洲沉积体系中,准层序及层组边界在地层记录中的表现形式随地理位置而变化;在完全由一种相构成的准层序、层组基准面旋回中,孔隙度和渗透率是A/S值变化的函数,在准层序及层组内部随A/S的变化,储层物性及其含油饱和度呈现一定的变化规律。

High-resolution sequence stratigraphy of fan deltas and its relations to oil and gas accumulation:A case study of the T76 block on the falling wall of the Shengbei fault in the Dongying depression, Shandong

The division and correlation of sequence stratigraphic units are constructed for the fan delta deposits in the upper submember of the 4th member of the Shahejie Formation in the T76 block on the falling wall of the Shengbei fault in the Dongying depression,Shandong on the basis of geological data,seismic sections and well logs.These fan delta deposits are divided into 4 parasequences,18 bed sets and 29 beds.In the fan delta depositional system,the boundaries of the parasequences and bed sets are changed with the geographic positions,whereas in the base-level cycles of the parasequences and bed sets in a single facies,the porosity and permeability are the function of A/S ratios.The physical properties and oil saturation in oil reservoirs also display similar regular changes.