Abstract:

The area percentage of lake and ocean basins is from 71% to 83% of the earth in the geological history, but the total area of oil and gas fields is little. Some basin has petroleum, and some has no petroleum. Some basin is rich in petroleum, and some basin is poor. The amount of organism in the sedimentary rock determined the quantity of oil and gas. Nourishment was the key factor for organism growth and river was the main source of nourishment in the basin after Carboniferous. There were many rivers around the lakes in the Mesozoic and Cenozoic periods in China. The nourishment was abundant in those basins. The growth and preservation of the organism were controlled by the rates of deposit and subside of basins. The source rock was rich in the basin deposited with low rate, and the source rock was poor in the basin deposited with high rate. The marine sediments distributed in the southeastern coast of China. The correlation between marine source rock and river in the Cenozoic was obvious. The middle-big gas fields located in the front of river (delta). It is the best way for “determining source” to search the river and the corresponding delta of marine. The most oil-bearing basins were correlative with the lake-delta-river system or the ocean-delta-river system in the Upper Paleozoic. The most oil-bearing basins were also correlative with the lake-delta-river system or the gulf-delta-river system in the Cenozoic of the world.

Key words: river, oil-bearing basin, sedimentary rock, organism, source rock, correlation

摘要：

地质历史时期湖盆和海盆面积占地球面积的71%～83%，但含油气面积却很少；并且有的盆地含油气，有的盆地不含油气；有些盆地富油气，有些盆地贫油气。沉积岩中有机质数量决定了油气的生成量，也就决定了盆地的油气富集程度。营养物质是有机物生长的最重要因素，石炭纪以后河流是全球含油气盆地中营养物质的主要来源。中国中—新生代湖盆周围河流发育，其内营养物质丰富，有机物的生长和保存主要取决于湖盆的沉积和沉降速率，欠补偿沉积湖盆的烃源条件好，过补偿沉积的烃源条件差。中国新生代海相沉积主要分布在东南沿海，新生代海相烃源岩与河流关系密切，已发现的大—中型气田均位于大型河流前缘（三角洲内），寻找新生代河流及对应海相三角洲是“定源”的有效途径。在全球，晚古生代—中生代富含油气盆地大部分与河流—三角洲—湖泊体系或河流—三角洲—海湾体系密切相关，而新生代富含油气盆地绝大部分也与河流—三角洲—湖泊体系或河流—三角洲—海湾体系相共生。

关键词: 河流, 含油气盆地, 沉积岩, 有机质, 烃源岩, 共生关系