现代地质2012，Vol.26Issue(2)：384-392,9.
鄂尔多斯盆地姬塬地区长7段泥岩古孔隙度恢复方法研究
Restoration of Paleo-Porosity of Shale within Chang 7 Member of Yanchang Formation, Jiyuan, Ordos Basin
摘要
Abstract
The shale within Chang 7 Member of Yanchang Formation in Triassic is an important source rock of Mesozoic reservoirs in Ordos Basin. The paleo-pressure in the period of accumulation plays a vital role for the hydrocarbon migration, and the changes of paleo-porosity represent the characteristics of the paleo-pressure evolution. So according to the mechanism of hydrocarbon fluid expulsion and overpressure release from the period of accumulation to the maximum burial depth, this article presents a new method that can extrapolate the paleo-porosity of shale within Chang 7 Member in the period of accumulation on the basis of the relationship between porosity increment and the maximum depth. Through analyzing the characteristics of present shale compaction profiles, there is an exponent relationship between the porosity increment and the maximum depth of undercom-pacted shale within Chang 7 Member. Then by using this relationship, the increment of shale porosity in the period of accumulation can be extrapolated and by combining the porosity of normal compaction trend, the total porosity of undercompacted shale within Chang 7 Member in the period of accumulation can be restored effectively. The paleo-porosity of shale within Chang 7 Member in the period of accumulation is generally high and the porosity ranges from 23% to 35% , indicating that the undercompaction of shale in the accumulation period is strong, and the abnormal high pressure is the main source rock expulsion power.关键词
孔隙度/欠压实泥岩/异常高压/长7段泥岩/延长组/姬塬地区Key words
porosity/ undercompacted shale/ abnormal high pressure/ the shale within Chang 7 Member/ Yanchang Formation/ Jiyuan area分类
能源科技引用本文复制引用
王菁,刘震,朱文奇,胡晓丹..鄂尔多斯盆地姬塬地区长7段泥岩古孔隙度恢复方法研究[J].现代地质,2012,26(2):384-392,9.基金项目
国家油气重大专项项目"岩性地层油气藏成藏规律、关键技术及目标评价"(2008ZX05001). （2008ZX05001）
