辽河坳陷清水洼陷古近系沙河街组深层烃源岩特征及油气成藏模式  

Characteristics of deep source rocks and hydrocarbon accumulation model of Paleogene Shahejie Formation in Qingshui subsag,Liaohe Depression

作　　者：朱康乐 高岗[1,2] 杨光达[4] 张东伟[4] 张莉莉 朱毅秀[1,2] 李婧 ZHU Kangle;GAO Gang;YANG Guangda;ZHANG Dongwei;ZHANG Lili;ZHU Yixiu;LI Jing(College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;No.7 Oil Production Plant,PetroChina Changqing Oilfield Company,Xi’an 710018,China;Research Institute of Exploration and Development,PetroChina Liaohe Oilfield Company,Panjin 124010,Liaoning,China;No.8 Oil Production Plant,PetroChina Changqing Oilfield Company,Yulin 718600,Shaanxi,China;Research Institute of Exploration and Development,PetroChina Yumen Oilfield Company,Jiuquan 735000,Gansu,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]中国石油长庆油田公司第七采油厂,西安710018 [4]中国石油辽河油田公司勘探开发研究院,辽宁盘锦124010 [5]中国石油长庆油田公司第八采油厂,陕西榆林718600 [6]中国石油玉门油田公司勘探开发研究院,甘肃酒泉735000

出　　处：《岩性油气藏》2024年第3期146-157,共12页Lithologic Reservoirs

基　　金：国家科技重大专项“渤海湾盆地北部油气富集规律与油气增储领域研究”(编号:2016ZX05006-005)资助。

摘　　要：通过有机碳、岩石热解、氯仿沥青“A”、饱和烃色谱-质谱和流体包裹体等的分析,对辽河坳陷清水洼陷古近系沙河街组深层烃源岩特征和油气成藏模式进行了详细研究。研究结果表明:(1)辽河坳陷清水洼陷古近系沙河街组深层烃源岩主要发育在E2s32亚段、E2s33亚段和E2s4段,其中E2s32亚段Ⅱ小层泥岩最为发育,主要为深灰色厚层泥岩,整体厚度约170 m。(2)研究区深层烃源岩总有机碳质量分数平均可达1.60%,生烃潜量平均值为2.82 mg/g;有机质类型以Ⅱ1—Ⅲ型为主,主要为浮游植物与高等植物混合贡献,为弱氧化—弱还原的湖相咸水沉积环境;烃源岩有机质丰度为0.5%~1.5%,普遍达到大量生烃阶段,部分已达到高成熟演化阶段。(3)研究区深层烃源岩在距今38 Ma时进入生油窗,距今20 Ma时开始生成天然气;流体包裹体显示研究区存在2期油气充注,分别为38~26 Ma和20 Ma~现今,与生烃演化史匹配。Based on the analysis of organic carbon,rock pyrolysis,chloroform bitumen“A”,saturated hy carbon chromatography-mass spectrometry and fluid inclusions,the characteristics of deep source rocks and hy‐drocarbon accumulation model of Paleogene Shahejie Formation in Qingshui subsag of Liaohe Depression were analyzed.The results show that:(1)The deep source rocks of Paleogene Shahejie Formation in Qingshui subsag are mainly developed in E2s32 submember,E2s33 submember and E2s4 member,mudstone of sublayerⅡof E2s32 submember is most developed,mainly dark gray thick mudstone,with an overall thickness of about 170 m.(2)The average TOC content of the deep source rocks in the study area can reach 1.60%,and the average hydrocarbon generation potential is 2.82 mg/g.The organic matters are mainly typeⅡ1-Ⅲ,mainly contributed by the mixing of phytoplankton and higher plants,and are in a weakly oxidizing-weakly reducing lacustrine saline water sedi‐mentary environment.With Ro value ranging from 0.5%to 1.5%,the source rocks have generally reached the stage of massive hydrocarbon generation,and some have reached the stage of highly matured evolution.(3)The deep source rocks in the study area entered the oil-generating window at 38 Ma,and a large amount of natural gas began to be generated at 20 Ma.Fluid inclusions show that there are two stages of oil and gas charging in the study area,namely 38-26 Ma and 20 Ma to present,matching the evolution history of hydrocarbon generation.

关 键 词：烃源岩地球化学特征 生物标志化合物 流体包裹体 咸水湖 成藏模式 沙河街组 古近系 清水洼陷 辽河坳陷 

分 类 号：TE357.4[石油与天然气工程—油气田开发工程] P618.13[天文地球—矿床学]