摘要
随着深层油气成为目前油气勘探的主战场,高熟-过熟烃源岩评价及原始有机质丰度恢复成为深层油气勘探的首要基础工作。东北地区松辽盆地西部外围上二叠统林西组沉积厚度巨大,未发生广泛的区域变质,发育数套高熟-过熟烃源岩,已有研究显示,该区是进行高熟烃源岩评价的典型地区。但仅依据实测有机质丰度和生烃潜力数据会极大的降低油气资源潜力评估的准确性,有必要进行烃源岩原始有机质丰度恢复。目前,自然剖面法、热解模拟实验法、物质平衡法、理论推导法等是常用的原始有机质丰度恢复方法。在对区域内地质资料较丰富的林西组剖面各项有机地球化学参数进行矫正恢复的基础上,开展多种方法原始有机质丰度恢复,依据恢复原始氢指数指示的原始有机质类型作为判别参数进行方法选择和矫正。研究结果表明,化学动力学法、降解率法和热解模拟经验图版法为适合松辽盆地西部外围林西组烃源岩原始有机质丰度恢复的最佳方法。有机质恢复系数平均可达1.65,恢复后林西组原始有机质丰度达到“好”级别,表明松辽盆地基底古生界林西组具有优质的“油气源”条件,值得进一步勘探。
With deep oil and gas becoming the main battlefield of oil and gas exploration at present,the evaluation of high-mature and over-mature source rocks and the recovery of original organic matter abundance are the primary basic work for deep oil and gas exploration.The sedimentary thickness of the Upper Permian Linxi Formation in the western periphery of the Songliao Basin in Northeast China is huge.There is no extensive regional metamorphism,and several sets of high-mature and over-mature source rocks are developed,and the research shows that it is a typical area for the evaluation of high-mature source rocks.However,only based on the measured organic matter abundance and hydrocarbon generation potential data will greatly reduce the accuracy of oil and gas resource potential assessment.It is necessary to restore the original organic matter abundance of source rocks.At present,natural section method,pyrolysis simulation experiment method,material balance method,theoretical derivation method and so on are commonly used methods to restore the abundance of original organic matter.Based on the correction and restoration of various organic geochemical parameters of the Linxi Formation section with abundant geological data in the region,various methods were carried out to restore the original organic matter abundance.The method selection and correction were carried out according to the original organic matter type indicated by the restored original hydrogen index as the discriminant parameter.The chemical kinetics method,degradation rate method and pyrolysis simulation empirical plate method are the best methods for restoring the original organic matter abundance of Linxi Formation source rocks in the western periphery of Songliao Basin.The average recovery coefficient of organic matter can reach 1.65,and the original organic matter abundance of Linxi Formation reaches“good”level after recovery,indicating that the Paleozoic Linxi Formation in the basement of Songliao Basin has high-quality“oil and gas source”conditions,which is worthy of further exploration.
作者
类兴璇
孙平昌
牛大鸣
LEI Xingxuan;SUN Pingchang;NIU Daming(College of Earth Sciences,Jilin University,Changchun,Jilin 130061;Jilin Provincial Key Laboratory of Oil Shale and Paragenetic Energy Minerals,Changchun,Jilin 130061)
出处
《中国煤炭地质》
2023年第10期14-22,共9页
Coal Geology of China
基金
中国地质调查局项目“深部地质调查”(DD20230008)
中国地质调查局项目“大陆典型地区深部地质调查”(DD20221643)。
关键词
松辽盆地西部外围
上古生界
林西组
高-过熟烃源岩
原始有机质丰度恢复
the western periphery of Songliao Basin
Upper Paleozoic
Linxi Formation
high-over mature source rocks
restoration of original organic matter abundance
