松辽盆地深层火山岩气藏富集规律与勘探前景

Enrichment and Exploration Prospects in Deep Volcanic Gas Reservoirs in Songliao Basin

松辽盆地深层为多个独立断陷组成的断陷群,火山岩为深层天然气藏主要储集层。在对深层火山岩气藏形成条件和成藏富集规律系统分析的基础上,提出深层火山岩气藏具有近距离运移成藏,围绕主断槽、沿断裂分布的特点;烃源岩、储集层和断裂共同控制气藏的分布。烃源岩、火山岩都发育且配置关系良好并具有一定构造背景的区带为有利勘探区带。目前未突破的断陷多,勘探潜力大。营城组火山岩依然是下步勘探的重点,火石岭组是火山岩气藏勘探的新层系;深层碎屑岩分布广,烃源岩与储集层大面积直接接触,是深层勘探重要的接替层系。

The deep zone of Songliao basin is made up of a group of separated fault depressions. The volcanic rocks are the major reservoirs for deep gas exploration. Based on systematically analyses of the formation condition and the gas accumulation pattern, it is suggested that the deep volcanic gas reservoirs are characterized by the short distant migration, distribution around main trough and along the fault, and controlled by source rocks, reservoirs and faults. The areas with both developed source rocks and volcanic reservoirs are the favorable ex- ploration zones. For exploration prospect, there are many fault depressions that have not yet made a breakthrough, such as Yingcheng forma-tion and Huoshiling formation which are all exploration targets with potentials. The widespread deep clastic rocks where the source rocks di-rectly connected with reservoirs in large area could be as important succeeding zones for deep exploration in this basin.