海相碳酸盐岩烃源岩的研究进展

PRESENT SITUATION AND PRINCIPAL PROGRESS IN THE RESEARCH ON MARINE CARBONATE SOURCE ROCKS

文章就碳酸盐岩烃源岩有机质丰度下限标准、有机质的赋存形式、生烃机制与生烃模式等方面的研究现状、主要进展进行讨论。目前对有机质丰度下限认识不一 ,石油勘探部门所采用的标准也很低 ,应用效果不理想 ,进而提出以 0 .5 %作为下限标准 ,现场应用效果很好。在成岩演化过程中 ,不同赋存形式的有机质相互转变 ,在不同演化阶段的生烃量和生烃类型也存在较大差异。生烃模式的研究主要采用干法、加水以及小玻管热模拟实验 ,提出了“三段式”生烃模式 ,发现不同赋存状态的有机质地球化学特征不同。文章对于一些碳酸盐岩生烃研究热点问题的讨论希冀引起人们对碳酸盐岩生烃问题的关注 ,进而推动我国海相碳酸盐岩的基础理论研究。

The present situation and principal progress in the researches on the abundance cutoff criteria and occurrence shapes of organic matters in marine carbonate source rocks and their hydrocarbon generation mechanisms and patterns are analyzed in the paper. At present, the abundance cutoff criteria of organic matters are various and the criterion used by petroleum exploration departments is very low, its application effect being poor. For this reason, it was proposed that the 0.5% may be taken as the abundance cutoff criterion. Through applying on the spot, a good result has been obtained. In the course of diagenetic evolution, the hydrocarbon generating amount and type were greatly different in various evolution stages because of the interconversion of the organic matters with distinct occurrence shapes. The by drocarbon generation pattern was studied mainly by use of dry process, watering method and grass tubule thermal simulation experiment: a 'Three-stage like' hydrocarbon generation pattern was put forward; and it was found that the geochemical characteristics of the organic matters with distinct occurrence shapes are different. In the paper, the discussion on the hot points of the research on the hydrocarbon generation in carbonate rocks will undoubtedly cause people's attention to this problem, thus promoting the basic theoretical research on the marine carbonate rocks in China.