中国南方盆地覆盖类型及油气成藏

Overlay relationship of basins and hydrocarbon accumulation in South China

根据盆地演化及生储盖组合特征,将中国南方盆地叠合关系分为覆盖型(连续覆盖型、间断覆盖型)和非覆盖型(下组合保持型、上组合保持型)。不同的覆盖关系对烃类的生成、演化、运移、保存或破坏有不同程度的影响。在不同覆盖类型的盆地中,以连续覆盖型盆地的油气勘探前景最为优越;具有间断覆盖特点的江汉南部的沉湖—土地堂复向斜和苏北盆地的南陵—句容—海安区块,其地质条件较为有利;上组合保持型覆盖地区的油气前景值得认真研究和探索,就保存条件来说,阿坝地区勘探前景优于南盘江地区;下组合保持型地区也具有良好的油气勘探远景;对于那些由于大型推覆构造所形成的特殊覆盖关系地区,下盘海相地层中的油气成藏和勘探值得重视。

Based on the basin evolution and source-reservoir-cap combination property, the overlay relationship of basins in South China was divided into two types of the covered type （including continuous covered type and discontinuous covered type） and the uncovered type （including upper assemblage holding type and lower assemblage holding type）. The different superimposed relationships of basins have the various effects on the formation, evolution, migration, conservation and destruction of hydrocarbon. It is sugges-ted that the prospecting of continuous covered type basin is the most superiority. The Chenhu-Tuditang double synclines in the southern Jianghan Basin and Nanling-Jurong-Hai＇ an Block in the northern Jiangshu Basin are the discontinuous covered types and have favorable geology conditions. The prospect of oil and gas in upper assemblage holding type areas is worthy to be studied. The preservation conditions of A＇ ba area may be better than that of Nanpanjiang area. The areas of lower assemblage holding type also have a good prospect for oil and gas exploration. The exploration of oil-gas reservoirs in footwall marine bed of those areas with special overlay relations resulted from large napped structure should be highlighted.