川东北及川东区天然气成因类型探讨

GENETIC TYPES OF THE NATURAL GAS IN THE NORTHEAST AND THE EAST OF SICHUAN BASIN

刘光祥 陶静源 潘文蕾 吕俊祥

LIU Guang-xiang TAO Jing-yuan PAN Wen-lei LÜ Jun-xiang

中国石化 勘探开发研究院 无锡实验地质研究所, 江苏 无锡 214151 2. 武汉市东西湖教校, 湖北 武汉 430040

Wuxi Research Institute of Experimental Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214151, China 2. West east lake TV University, Wuhan, Hubei 430040, China

通过对川东北、川东区11口钻井天然气组分及其烷烃碳同位素的研究表明,两区天然气成因类型明显有别,川东北天然气为过成熟裂解混源气,其中,Ⅱ—Ⅲ1类型母质烃源岩的贡献可能大于Ⅰ1—Ⅰ2类型母质烃源岩的贡献;川东区建南气田长兴、飞三、嘉一产层天然气多属Ⅰ1—Ⅰ2类型母质烃源岩过成熟裂解混源气;个别天然气表现为煤型气与油型气的混源气,腐泥型有机质的贡献可能大于腐殖型有机质的贡献;石炭系产层天然气可能为志留系所生原油的二次裂解气。

Based on study of the component and its carbon isotope of natural gas samples from the Northeast and the East of Sichuan Basin,the genetic types of the natural gas in different regions are different.Natural gas in the Northeast was mainly derived from the over matured source rocks with type Ⅱ-Ⅲ1 kerogen;besides,it is supposed that type Ⅱ-Ⅲ1 organic matter makes more contribution than that of type Ⅰ1-Ⅰ2 type kerogen in this region.However,natural gas samples from Jiannan gas field(Upper Permian and Lower Triassic)showed that they were mainly generated by over matured source rocks with kerogen typesⅠ1-Ⅰ2 and part of gas showed characteristic of sapropelinite and humic organic matter origin.Furthermore,natural gas in Carboniferous pool was from the secondary cracking of oil derived from Silurian source rocks.

中国石化集团公司重点科技攻关项目(P00040).

https://doi.org/10.11781/sysydz200206512