渤海湾盆地东营凹陷滨南地区玄武岩-烃源岩共生体的油气地质特征

PETROLEUM GEOLOGY OF BASALT-SOURCE ROCK PARAGENETIC ASSOCIATION IN BINNAN AREA, THE DONGYING DEPRESSION OF THE BOHAIWAN BASIN

渤海湾盆地东营凹陷滨南地区主力生油层中发育规模不等的玄武岩,形成了玄武岩-烃源岩共生组合体。其中的烃源岩有机质丰富,而且岩性为钙质泥页岩和油页岩;玄武岩气孔和溶蚀孔洞发育,是良好的储集层。火山物质(包括过渡金属)与有机质在长期的埋藏作用中相互作用,使有机质生烃过程得到催化和加氢作用,在较低温度条件下生成大量烃类;玄武岩在有机酸作用下发生强烈蚀变作用,产生大量的储集空间。因此,玄武岩-烃源岩共生体是良好的生储盖组合体。

Different scales of basalt was developed in the major hydrocarbon-generating strata of Binnan area, the Dongying Depression of the Bohaiwan Basin, which composed basalt-source rock paragenetic association. In the association, the source rocks which were enriched with organic matter were composed of calcareous argillutite and oil shale lithologically, and the basalt which developed vesicles and solution pores was good re-servoirs. During the long time of burial, the interaction of volcanic material (including transition metals) with organic matter brought about catalysis and hydrogenation in the hydrocarbon-generating process of organic matter, and resulted in the generation of large amount of hydrocarbons at lower temperature. Meanwhile, the basalt underwent intense alteration under the action of organic acids, and formed a great amount of reservoir spaces. Therefore, the basalt-source rock paragenetic association is a very good habitat for oil and gas accumulation.