阿尔及利亚三叠盆地Hadjira区块油气勘探潜力

三叠盆地Hadjira区块是中国石油化工集团在阿尔及利亚实施的海外油气合作勘探区块之一。在收集前人研究资料的基础上，依据二维地震勘探资料和野外地质踏勘成果等对该区构造带及圈闭进行了确定，并通过对钻井岩心的分析化验，对该区的烃源岩、储集岩及盖层进行了研究。结果认为：该区主要烃源岩为志留系海相泥岩，次要烃源岩为奥陶系暗色泥岩；主要储层为三叠系SI砂岩，次要储层为奥陶系石英砂岩；圈闭为低幅度背斜。在对该区油气成藏基本地质条件研究的基础上，得出以下结论：烃源岩的发育程度控制了油气成藏分布；北东-南西向构造带是油气主要的聚集带；海西期不整合面及其上下砂岩层是油气运移的主要通道；该盆地南部的韦德迈阿次盆地志留系烃源岩及有利储集岩发育区为油气勘探的潜力区。

EXPLORATION POTENTIAL OF HADJIRA BLOCK IN THE TRIASSIC BASIN, ALGERIA

The Hadjira Block in the Triassic basin is one of the overseas exploration areas of SINOPEC in Algeria. The structural zones and traps are recognized through 2 D seismic survey and field geologic reconnaissance based on previous research results, and studies are performed on the source, reservoir and cap rocks with core data. It is believed that the source rocks are dominated by the Silurian marine mudstone, followed by the dark Ordovician mudstone, that the Triassic SI sandstones are the main reservoirs, followed by the Ordovician quartzose sandstone, and that the traps are mainly low amplitude anticlines. Based on study of the basic geologic conditions of hydrocarbon pooling in the study area, the following understandings are obtained: the development of source rocks controls the distribution of oil and gas reservoirs, the NE SW trending structural belt is the major zone for hydrocarbon accumulation, the Hercynian unconformity and the sandstones above and below it act as the main pathways of hydrocarbon migration, and the regions with highly developed Silurian source rocks and favorable reservoirs in the southern part of the study area are potential exploration targets.