关键词: 辽河坳陷, 东部凹陷, 天然气, 火山岩, 玄武岩, 勘探发现

Abstract: Volcanic oil and gas reservoirs are one of the key areas for oil and gas exploration in the Liaohe depression. Multiple middle-shallow volcanic oil reservoirs represented by trachyte have been discovered, although no breakthroughs were made in fields of deep volcanic rocks during natural gas exploration. In order to make large-scale resource discoveries, research on deep volcanic rocks was carried out. Through core observation, single well analysis, reservoir description, source rock evaluation, and other research, combined with wide-broadband, wide azimuth and high-density seismic data and time-frequency electromagnetic technology, multiple volcanic rock targets were identified. Risk exploration Well JT1 was successfully deployed and drilled, obtaining high-production industrial gas flow. Studies show that the deep source rocks of the third member of the Shahejie Formation in the eastern sag have the potential for large-scale gas generation, providing a rich material basis for large-scale gas accumulation. Compared with sedimentary rocks, the physical properties of volcanic rocks are less affected by burial depth, particularly the basaltic breccia, which has good reservoir conditions. The volcanic rocks in the source rock formations are wrapped by mudstones, which act as both gas source rocks and cap rocks. Accumulation conditions are very favorable. The success of Well JT1 represents an important breakthrough in gas exploration in the eastern sag. This is of great instructive significance for the exploration of deep volcanic rocks in the Liaohe depression and even in the Bohai Bay Basin.