关键词: 中国, 大中型油气田, 烃源岩, 分布, 地质时代, 盆地类型, 岩性, 沉积环境

Abstract:

:Distribution of major source rocks in China' s large and medium_sized oil_g as fields is of diversifcation and complexi ty in geologic age , basin ty pes , lithology and sedimentary environment .These source rocks developed with strata from Middle Proterozoic to Cenozoic(excluding Devonian), among which the Mesozoic and Cenozoic layers are the most important .The basins that developed source rocks include the rif t basin of Mesozoic_Cenozoic , the cratonic basin of early Paleozoic , and the fo reland basin of Mesozoic and Late Paleozoic .There are quite large differences in distribution , geological and geochemical characteristics and hy drocarbon generation potential of source rocks between different types of basins .The source rocks include the marine carbonate and mudstone , and the transitional and terrest rial mudstone , coal measure strata and carbonate .The major one is lacust rine clastic rock .

Key words: China, large and medium_sized of oil_gas f ield, hy drocarbon source rock, dist ribution, basin type , rock lithology, sedimentary environment