利用油藏地质地球化学特征综合划分含油气系统

含油气系统的划分和范围的确定关系到油气勘探的方向和有利区带的选择,油源对比是含油气系统划分的关键.在缺乏成熟烃源岩样品的情况下,须结合油气藏的地质特征和演化历史,才能科学地划分含油气系统.据中非Muglad盆地Nugara坳陷同-构造上两个油田的地质分析和原油地球化学分析,把坳陷划分为两个独立的含油气系统,不同油田属于不同的系统.这一思路可为今后复杂构造演化区和裂谷盆地含油气系统研究提供借鉴.

DIVISION OF PETROLEUM SYSTEMS BY USING INTEGRATED GEOLOGICAL AND GEOCHEMICAL ANALYSES

The determination and division of petroleum systems might be a key problem for the hydrocarbon exploration, namely, how to choose a prospective target area. The correlation of oil source rocks must be the key to determine petroleum systems. In case that no mature source rock samples were available, to integrate the geological characteristics with the evolution history of oil pools should be a scientific way to divide petroleum systems. Based on the geological and geochemical analyses, this paper took two oilfields in the same structural rise of Nugara Subbasin, Muglad Basin in Sudan, Central Africa, as an example, and divided the subbasin into two independent petroleum systems. The authors found that the oils of two oilfields might be sourced from different systems. This idea should be interested to forecast petroleum prospects in rift basins with complicated tectonic evolution.