论三角洲对南海海相油气田分布的控制作用

南海是全球重要的油气富集区之一，在新生界已发现约340个油气田，原油可采储量达17.6×10⁸t，天然气可采储量为5.0×10¹²m³，油气主要富集于渐新世以来三角洲—海相沉积体系中，三角洲对南海含油气盆地成烃、成储和成藏具有重要的控制作用。海陆过渡相烃源岩是南海含油气盆地的重要烃源岩，三角洲体系是煤系烃源岩发育的重要场所，河流—三角洲体系所携带的陆生高等植物有机质有利于陆源海相泥质烃源岩的发育。三角洲体系发育的碎屑岩储层厚度大、分布广、物性好，与海相泥岩构成良好的储盖组合。三角洲是南海油气富集的重要场所，三角洲对南海海相油气田的形成和分布具有重要的控制作用。

On the control effect of deltas on the distribution of marine oil and gas fields in the South China Sea

The South China Sea is one of the most important hydrocarbon enrichment areas in the whole world; about 340 oil and gas fields have been discovered in the Cenozoic. The recoverable reserves of crude oil and gas are 17.6×10⁸t and 5.0×10¹²m³, respectively. The oil and gas have mainly enriched in the delta-marine sedimentary system since the Oligocene. Deltas play an important role in controlling hydrocarbon generation, reservoir formation, and accumulation in petroliferous basins in the South China Sea. The marine-continental transitional source rocks play a key role in petroliferous basins in the South China Sea. The delta system is an important place for the development of coal-bearing source rocks. The organic matter of terrestrial plants carried by the fluvial-delta system is conducive to the development of terrigenous marine muddy source rocks. The clastic reservoirs developed in the delta system are characterized by large thickness, wide distribution and good physical properties, and form a favourable reservoir-seal assemblage including marine mudstones. The deltas are a vital place for oil and gas accumulation in the South China Sea, and have a crucial control effect on the formation and distribution of marine oil and gas fields in the South China Sea.