南方海相烃源岩特征分析

CHARACTERISTICS OF THE MARINE HYDROCARBON SOURCE ROCKS IN SOUTH CHINA

文章通过对地化基干剖面及重点盆地南方海相烃源岩的解剖,分析了中国南方海相烃源岩的地球化学特征及沉积成岩环境,探讨了有关南方海相烃源岩评价的几个关键问题。认为:①南方海相发育 4 套区域性主力烃源岩层和7套地区性烃源层;海相烃源岩主要是泥岩,有机质丰度高,但热演化程度普遍很高;②海相烃源岩发育于5种有利的构造沉积环境中;③海相烃源岩往往具有“双重母质”—浮游藻类和底栖叶状体植物(宏观藻类);④南方海相烃源岩研究还存在着碳酸盐岩丰度下限值、评价指标、油源对比指标、二次生烃等多方面的问题,需要继续深化研究讨论。

Through dissecting the marine hydrocarbon source rocks on the main geochemical sections and in the key basins in South China, the authors analyze their geochemical characteristics and sedimentary and diagenetic environments and discuss several key problems related to their evaluations. It is pointed out that there are 4 series of regional main hydrocarbon source rocks and 7 series of local hydrocarbon source rocks in the marine strata in South China; the marine hydrocarbon source rocks are mainly composed of mudstones with high organic matter abundance and high thermal evolution level; these rocks are developed in five favourable structural-sedimentary environments; these rocks often possess “dual-kerogen”, i.e. planktonic algae and benthic faliaceous plants (macro-algae); and the problems needful for further research include the cutoff value and evaluation indexes of organic matter abundance in carbonate rocks, the source correlation markers, the secondary hydrocarbon generation and so on.Formation, Hydroc