摘要
通过精细岩心观察发现，大庆油田西部英台地区白垩系粉砂岩中发育大量泥质薄层——泥膜，厚度在0．5～3．0mm。大部分泥膜平面并不平滑，而是发生了多种不同形状的微变形构造，其中相当一部分发生了上下砂岩的穿透。泥膜因其渗透性极差而具有很强的垂向阻隔性，理想情况下一层稳定的泥膜能够将所在范围内的上下砂岩完全隔开，将一整套砂体分隔成上下两个独立的油水系统，大量稳定泥膜的发育则使区域内的油水分布变得非常复杂。而频繁发育的小规模或发生穿透的泥膜在油田开发时则阻隔了砂岩内部的油水运移路线，起到降低砂岩孔渗性的作用。研究区低角度浅水三角洲沉积背景是毫米级泥膜大量发育的主控因素，毫米级泥膜的发育频率与沉积微相和单层砂体厚度有密切联系，可以通过局部取心井的泥膜统计来对附近区域的泥膜发育数量进行预测。
Based on core observation, there are a lot of mud laminae （called mud-films, with thickness of 0. 5-3 mm） developed in the Cretaceous siltstone in the western Yingtai area, Daqing Oilfield. Surfaces of most mud-films are not smooth, but grow with some sorts of micro-deformation structure, and some of them are penetrated by the silt up and down. The mud-films have strong vertical isolation due to their poor permeability. Therefore, under ideal circumstances, a steady mud film can isolate the upper and lower sandstone in its coverage entirely, and divide a set of sand body into two independent oil-water systems. The growth of many steady mud-films can increase the complexity of local oil-water distribution. Some frequently-developed small-scale or penetrated mud-films can obstruct the oil-water migration route inside a reservoir, playing a role in lowering the sandstone permeability. The main factor of the abundant growth of ramlevel mud-films is the sedimentary background of the shallow delta with low angle in study area, and the development frequency of mm-level mud-films is closely related to the sedimentary microfacies and single-layer sand-body thickness. The mud-film development status in nearby area can be predicted by mud-film statistics from local corings.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2009年第4期442-447,共6页
Petroleum Exploration and Development
基金
大庆油田公司攻关项目"新站以西地区多层位油藏群成藏条件及含油富集区块优选"
关键词
英台地区
毫米级泥膜
阻隔
非均质性
剩余油
Yingtai area
mm-level mud-film
isolation
inhomogeneity
remaining oil
