阜新凹陷白垩系源岩生烃特征及天然气成因  

CHARACTERISTICS OF CRETACEOUS SOURCE ROCKS AND THE ORIGIN OF NATURAL GAS IN FUXIN SAG

作　　者：王辉[1] 刘忆彤[2] 

机构地区：[1]中石油辽河油田公司,辽宁盘锦124010 [2]东北石油大学地球科学学院,黑龙江大庆163000

出　　处：《海洋地质前沿》2013年第4期33-40,共8页Marine Geology Frontiers

基　　金：国家重大科技专项<大型油气田及煤层气开发>07项目"中国大型气田形成条件;富集规律及目标评价"(2011ZX05007)

摘　　要：对阜新凹陷白垩系源岩生烃基本条件进行了详细分析,并结合原油、天然气特征及油源对比研究,认为研究区存在浅湖相泥岩和沼泽相煤系源岩(由煤和泥岩构成)2种不同沉积环境下形成的烃源岩。2种源岩虽然层位不同,但在其有机质丰度和类型上并不存在较大的差异,生烃特征也基本相似,都具备成气为主、成油为辅的煤成烃特征,有机质成熟度及烃源岩的分布控制了源岩在整个演化过程中的生烃类型和数量。研究表明:在有机质受热演化的各个阶段,都会伴随着不同类型有机成因气的产出,未成熟阶段为煤型生物气,成熟—高成熟阶段主要为煤型热解气,还伴生少量的石油。In this paper, the Cretaceous source rocks and their hydrocarbon genetic conditions in the Fuxin sag are discussed in details. Based on the characteristics of natural gas and crude oil and their correlation with oil sources, it is believed that there are two kinds of sedimentary environments of source rocks in this area. One is the lacustrine mudstone and the other is coal bearing mudstone of swamp facies. The two kinds of source rocks are different in horizon,but the abundance and types of organic matter show no great differences,and the hydrocarbon generation characteristics are also simi- lar. Both of them are dominated by coal gas, supplemented by oil generation. The characteristics of hydrocarbon generation, organic matter maturity and hydrocarbon source rock distribution patterns control the types and abundance of hydrocarbons. Different types of gas were formed in different ther- mal evolutionary stages. In the immature stage, coal type of biogenic gas dominated,while in the ma- ture-high mature stage, gas of coal pyroysis dominated with small amount of oil. The results of the study will no doubt be helpful to the resource evaluation and oil and gas exploration in the region.

关 键 词：源岩 有机质 煤阶 成熟度 演化阶段 生物气 热解气 

分 类 号：P618.13[天文地球—矿床学]