通过对上、中、下扬子区121个地表及钻井剖面烃源岩的密集扫描取样和地化分析,系统研究了下寒武统、上奥陶统一下志留统、上二叠统、下二叠统四套区域性海相烃源岩的厚度及有机质丰度的纵横向分布,明确了海相烃源岩在纵向上以下寒武统和上二叠统为最好,横向上以上扬子区为最好,其次为下扬子区;确定了五个烃源岩发育区.明确了海相烃源岩以泥岩为主,碳酸盐岩烃源岩只出现在下二叠统栖霞组-茅口组,实测最大厚度为150m,从而表明中国南方不存在上千米厚的碳酸盐岩烃源岩.对四套海相烃源岩的厚度问题、层位问题、原始生烃潜量和碳酸盐岩烃源岩的鉴别问题等提出了认识.

A systematic study on the vertical and horizontal distributions of the thickness and the organic matter abundance for four suites of Paleozoic regional marine source rocks(〗〗3—S1，P1 and P2 ) has been made by geochemical analyses on the source rock samples from 98 outcrop profiles and 23 well profiles in Upper, Middle and Lower Yangtse River regions. It is clarified that in vertical the Lower Cambrian and Upper Permian source rocks are the best, and in horizontal the source rocks in Upper Yangtse River regions are the best and then those in Lower Yangtse River are the secondary, respectively. Five developmental source rocks areas are defined. It has shown that marine source rocks are predominated by mudstones in these areas and carbonate source rock occurs only in the Lower Permian Qixia-Maokou Formations with a measured maximum thickness up to 150m. It is proved that no one suite of carbonate source rock with a thickness over 1000m exists in Southern China. This study has bring forward some new insights into the thickness, developed zones and primary hydrocarbon-generating potential of the four suites of source rock as well as into the identification of carbonate source rocks.