黄骅坳陷莲花凝析气田的发现及其地质意义

Discovery of Lianhua condensate gas field in Huanghua Depression and its geological significance

渤海湾盆地黄骅坳陷是我国东部典型的含油气盆地,但潜山领域已发现的天然气田储量规模较小。近几年,通过勘探研究思路转变和地质认识创新,在黄骅坳陷南部乌马营潜山发现了莲花凝析气田,实现了来自煤系源岩的深层天然气勘探重要突破。随着重新认识潜山烃源岩条件、圈闭特征、储集空间和成藏模式,提出乌马营潜山石炭-二叠系煤系源岩规模生烃为油气成藏提供了充足的气源,多期构造演化控制形成多个大型构造圈闭是气田形成的基础,多套储层叠置发育,为油气大面积连片富集提供了有利空间,明确了古生界含油气系统具有内幕多层系叠置复式聚集的天然气成藏模式。所取得的理论认识指导了黄骅坳陷潜山深层内幕原生油气藏的勘探突破,实践经验对于推动渤海湾盆地东部探区来自煤系源岩的天然气勘探具有重要指导意义。

The Huanghua Depression in Bohai Bay Basin is a typical petroliferous basin in eastern our country,but the reserves of natural gas fields discovered in buried hill area are small.In recent years,through the change of exploration research ideas and the innovation of geological understanding,the Lianhua condensate gas field has been discovered in Wumaying buried hill in the southern Huanghua Depression,realizing an important breakthrough in the exploration of deep natural gas from coal-measure source rocks.With the new understanding of buried hill source rock conditions,trap characteristics,reservoir space and accumulation model,it is proposed that the large-scale hydrocarbon generation of Carboniferous-Permian coal measure source rocks in Wumaying buried hill provides sufficient gas source for hydrocarbon accumulation,the formation of multiple large-scale structural traps controlled by multi-stage tectonic evolution is the basis for the formation of gas fields,multiple sets of superimposed and developed reservoirs provide favorable space for large-scale continuous enrichment of oil and gas,and it is clear that the Paleozoic hydrocarbon-bearing system has a natural gas accumulation model of inner multi-layer superimposed and compound accumulation.Theoretical understanding obtained has guided the exploration breakthrough of deep inner primary oil and gas reservoirs in the buried hill in Huanghua Depression,and the practical experience has important guiding significance for promoting the exploration of natural gas from coal measure source rocks in the eastern Bohai Bay Basin.