Title

Oil and gas source and reservoir characteristics in Fulongquan Subsag, Changling Depression, Songliao Basin

作者

徐文李浩陈延哲

Authors

Xu Wen Li Hao Chen Yanzhe

单位

中国石化东北油气分公司勘探开发研究院, 长春 130062 2. 中国石化石油勘探开发研究院无锡石油地质研究所, 江苏无锡 214126

Organization

Exploration and Development Research Institute, SINOPEC Northeast Oil & Gas Branch, Changchun, Jilin 130062, China 2. Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214126, China

摘要

利用天然气组成、轻烃、碳同位素和生物标志化合物等地球化学特征，结合地质条件，确定了松辽盆地长岭断陷伏龙泉地区油气成因及来源，建立了研究区不同构造带的油气成藏模式。研究表明，伏龙泉地区泉头组-登娄库组天然气以煤型气和凝析油伴生气为主，油气源主要为下部断陷层下白垩统沙河子组烃源岩，营城组和火石岭组烃源岩有部分贡献；不同构造带油气成藏存在差异，陡坡带主要为深大断裂控制下的次生油气藏成藏模式，具有“近源、深大断裂输导、后期强烈反转调整”的成藏特征，缓坡带主要为侧向运移的原生油气成藏模式。研究区下白垩统发育多套烃源岩、“Y”型断裂以及多个区域不整合面构成的三维网络输导体系，油气源条件与输导条件良好，同时嫩江组沉积末期强烈的构造反转运动形成的反转构造，提供了较有利的圈闭条件，具有一定的油气勘探潜力。

Abstract

Oil and gas genesis and accumulation patterns in different tectonic zones in the Fulongquan Subsag, Changling Depression, Songliao Basin, were determined according to natural gas composition, light hydrocarbon, carbon isotope, biomarker compounds and geologic conditions. The natural gas in the Quantou (K1q) and Denglouku (K1d) formations are mainly coal gas and condensate oil associated gas, mainly sourced from the Lower Cretaceous Shahezi Formation (K1sh) and partially from the Yingcheng (K1yc) and Huoshiling (K1h) formations. There are two reservoir-forming modes:One is the reservoir formation model of secondary oil and gas reservoirs under deep fault control, and has the characteristics of "near source, deep fault transmission and strong reversal adjustment" in the steep slope zone; the other is the lateral migration oil and gas accumulation model in the gentle slope zone. In the Fulongquan area, the oil and gas source conditions and the transport conditions are favorable. The Lower Cretaceous strata include three sets of source rocks and a reticular transport system which consisted of Y-type faults and multiple regional unconformities. The strong tectonic inversion at the end of the Nenjiang Formation formed a large number of inversion structures, which provided a favorable trapping condition. Therefore, the Fulongquan area has some potential for oil and gas exploration.

关键词：

天然气成因; 油气源对比; 成藏模式; 勘探潜力; 长岭断陷; 松辽盆地;

Keywords:

natural gas origin; oil or gas-source correlation; reservoir-forming pattern; hydrocarbon exploration potential; Changling Depression; Songliao Basin;

基金项目

国家科技重大专项（2011ZX05005-004）资助。

DOI

https://doi.org/10.11781/sysydz201703334

松辽盆地长岭断陷伏龙泉地区油气源及成藏特征分析