季曼-伯朝拉盆地油气地质特征及勘探潜力分析

Petroleum Geology Features and Exploration Potential Analysis in Timan-Pechora Basin

季曼-伯朝拉盆地是俄罗斯重要的含油气盆地之一,经历了前裂谷、裂谷、被动陆缘和前陆4期演化阶段,形成现今古被动边缘-前陆叠合的构造格局。盆地不同期次的构造演化及叠合效应控制着盆地的烃源岩、储层发育和分布,进而控制了油气分布规律。盆地的主要烃源岩和储盖组合多发育于中晚古生界,上泥盆统多马尼克组烃源岩是盆地的主力烃源岩;主力储层为中上泥盆统、石炭系-下二叠统的碳酸盐岩和碎屑岩,储层物性整体较好;圈闭类型多为岩性-构造型圈闭;盆地油气主要沿着早期裂谷的反转隆起分布。盆地勘探程度分布不均,其中东部前渊区以及海域勘探程度较低,油气地质综合分析表明,前渊地区是最有潜力的含气区,海域仍具有良好的勘探前景,是未来勘探的两个有利区带。

Timan-Pechora basin is one of the important petroliferous basins in Russia. It has experienced the 4 stages of evolution of pre-rift,rift,passive continental margin and foreland,and formed the present structural pattern which has ancient passive marginal edge and foreland superimposed effect. The tectonic evolution and superimposed effect of different stages of the basin control the development and distribution of source rocks and reservoirs in the basin,and then control the distribution of oil and gas. The main source rocks and reservoir-cap rock assemblages of the basin are mostly developed in the middle and late Paleozoic. The Domanik formation source rock of the upper Devonian is the main source rock of the basin. The main reservoir is the middle-upper Devonian,Carboniferous and lower Permian carbonates and clastic rocks,and the reservoir physical property is relatively good. The trap type is mostly lithologic-structural trap. The oil and gas in the basin are mainly distributed along the inversion uplift of the early rift. The exploration degree of the basin is unevenly distributed,of which the eastern foredeep and the sea area are relatively low. The comprehensive analysis of petroleum geology shows that the eastern foredeep is the most potential gas prospect area,and the sea area still has a good exploration prospect. They are the two favorable zone for future exploration.