259 / 2022-03-31 01:02:24

Study on Sedimentary Characteristics and Genesis of Dominant Reservoir of Lacustrin Mixed Rock Reservoir：Taking the Lower Member of Upper Ganchaigou Formation in Gasikule Oilfield as an Example

Lacustrine mixed rock;Dominant reservoir;Sedimentary facies;Palaeogeomorphology Palaeobathymetric

Abstract

In order to clarify the mixed sedimentary characteristics and the genesis of dominant reservoirs in the lacustrine sedimentary environment of saline lacustrine basin, this paper takes the lower member of Gasikule N₁ reservoir as an example to study the mixed sedimentary characteristics and the distribution characteristics of dominant reservoirs by analyzing the regional geological data, core analysis and logging data. The study shows that the lacustrine mixed deposition is characterized by multi-component mixing and multi-type superposition. The coastal and shallow lakes are the main development facies zone of interbedded mixed deposition, the interbedded mixed deposition is mainly developed in semi-deep lake facies, and the algal mixed deposition is mainly developed in shallow lake beach bar and underwater uplift. Finally, by restoring the paleogeomorphology and paleobathymetry at the early stage of sedimentation, the plane distribution of mixed-type dominant reservoirs in the study area is predicted, indicating that the southern area is the dominant reservoir distribution area.