潜山油气藏勘探理论与实践--以辽河坳陷为例

Exploration theories and practices of buried-hill reservoirs:A case from Liaohe Depressions

近年来,辽河坳陷潜山油气藏勘探不断取得重大突破,实现了由寻找成藏条件相对明显的高、中潜山向寻找埋藏更深、更隐蔽、更复杂的低潜山和潜山内幕油气藏的勘探转变。从基底构造活动、潜山类型、岩性及储集层特征、生烃系统、输导体系等多角度探讨了低潜山和潜山内幕油气成藏条件;同时,充分考虑潜山内幕油气藏的特点,紧密结合勘探实践,从潜山与油气的关系入手重新建立潜山内幕油藏实用分类方法,大大拓宽了潜山找油领域,形成了具有低幅度、多期裂缝、多油源充注特点的潜山内幕目标成藏模式。通过对辽河坳陷低潜山及潜山内幕油气成藏理论的研究与勘探实践,2001—2006年,低潜山和潜山内幕累计上报三级储量分别达2.54×108t和1.76×108t,为辽河油田增储稳产作出了重大贡献。

In recent years, various breakthroughs have been made in buried hill reservoir exploration in Liaobe Depression. Exploration targets have shifted from the Shallow-medium buried hill reservoirs with clearer reservoir forming conditions to the low and inner buried hill reservoirs with deeper, hidden and more complex features. Reservoir-forming conditions of low and inner buried hills were studied in aspects of basement tectonic activity, type of buried bills, lithology and reservoir characteristics, hydrocarbon generating system and hydrocarbon conducting system. A practical classification method of inner buried hill reservoirs has been re-established in accordance with the relationship between buried hills and hydrocarbon accumulations, by studying reservoir characteristics of inner buried hill reservoirs with consideration of exploration practices. Such a classification method has widened the hydrocarbon searching scope in buried hills, and built up a reservoir forming pattern for the exploration targets inside buried hills with low amplitude, multiphase fractures and multisource charging. Based on the theoretical studies and exploration practices of low and inner buried hill reservoirs, the 3P reserves reported for low and inner buried hill reservoirs reached 2.54×10^8 t and 1.76×10^8 t respectively from 2001 to 2006. The buried hill reservoirs have made significant contribution to increasing reserves and stabilizing production in Liaohe Oilfield.