鄂尔多斯盆地古生界气藏成藏模式及优势储层预测

鄂尔多斯盆地延长气田天然气勘探起步较晚,古生界气藏隐蔽性较强,勘探难度较大。为探究该地区气藏成藏模式,以沉积学原理为基础,从地层分布、构造特征、沉积相、储层主控因素等方面研究了延长气田南部地区古生界天然气成藏特征及富集规律。研究表明:延长气田相对优质储层是天然气成藏与富集的关键,储层规模决定气藏规模;优质储层发育主要受古地貌、岩石类型和后期成岩作用控制:优质储层主要发育在三角洲分流河道、河口坝中,富石英质沉积体系天然气富集程度较高。该研究成果对延长气田古生界气藏勘探开发具有重要指导意义。

Accumulation Pattern and Favorable Reservoir Prediction of Paleozoic Gas Reservoirs in Ordos Basin

Natural gas in Yanchang Gas Field Ordos Basin was explored relatively late. Paleozoic gas reservoir is buried deeply and difficult to explore. In order to explore the accumulation pattern of gas reservoirs in this area, the accumulation characteristics and enrichment pattern of Paleozoic gas reservoirs in the south of Yanchang Gas Field were studied in terms of stratigraphic distribution, tectonic features, sedimentary facies and reservoir controlling factors based on sedimentological principles. The study showed that the relatively high-quality reservoirs in Yanchang Gas Field were the key to natural gas formation and enrichment, and the reservoir size determined the scale of the gas reservoir; the development of high-quality reservoirs was mainly controlled by paleo-geomorphology, rock type and late diagenesis; high-quality reservoirs were mainly developed in deltaic distributary channels and estuary dams, and the quartz-rich sedimentary system was high in natural gas enrichment. There is much for reference of the study results to the exploration and development of Paleozoic gas reservoirs in Yanchang Gas Field.