摘要
江汉盆地盐间白云岩既是烃源岩又是非常规储集层。从资料显示的盐间顶部含油型高丰度油浸、油源对比所证实的存在下生上储多油源性、以及油气富集主要受控于古地形及裂缝带等表明，盐间白云岩内油气确实发生过运移。分析指出盐间油气成藏是在压实作用、浮力作用及毛细管压力等动力因素下，以盐间层内孔喉、微裂缝、盐层异常错位、盐间高压流体刺穿和盐间断层缝等４种通道模式，经历了盐间油气欠压实喉道阶段和盐间高压微裂缝间歇性阶段两大运移过程的结果。由于盐间储集层渗透性较差，油气运移规模和距离受到限制，因此，该区具有盐间白云岩油浸分布广泛、油藏不受构造控制的特点；形成的油气藏类型单调，区内主要形成孔隙型油藏，而局部裂缝发育带内形成孔隙一裂缝型油藏。最后，根据该区盐间白云岩油气运移、成藏的机理特点，提出了有针对性的油气运、聚效率新概念，即盐间油气初次运移效率、盐间油气可流动效率和盐间油气成藏效率，并分别给出多种解决计算方案。
Intersalt dolomites are both source and reservoir formations. Information shows that there are highly Oil immersion body at the top of intersalt formations and multiple source shown by oil correlation that there are oils come from the bed underneath. Oil and gas accumulation are mainly controlled both by paleogeomorphology and fracturing belts. All these facts show that oil and gas migration do occur in the intersalt dolomites. An analysis shows that oil-gas pool forming in the intersalt formations is the result of actions of dynamic factors such as compaction, flotation, and capillary pressure etc, through four channel models: pore-throat in the intersalt formations, microfractures, dislocation of salt formations and combined effects of intersalt high pressure fluid piercement and intersalt faults. This means the pool forming experienced two main stages of intersalt undercompaction and intermittent high pressure microfracturing. Because intersalt reservoirs have rather low permeability, thus such migration are rather limited in scale and distance. Therefore the oil/gas reservoirs in this district have a characteristic of widely distributed oil immersion and the oil are are not controlled by structures The types of oil and gas ed formed are relatively simple Mainly porous type reservoirs formed in some locally fractured belts. Finally some new ideas on oil and gas migration and accumulation are suggested according to the characteristic of oil/gas migration and accumulation efficiencies, which are primary migration efficiency of oil and gas in intersalt formations, flow efficiency of intersalt oil and gas, and pool forming efficiency of intersalt oil and gas, for them, various calculation procedures are suggested. This study gives a basis for the prediction of abundant accumulation belts and locations in the intersalt formations and the evaluation of oil and gas resources in dolomite formations.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2000年第4期71-75,共5页
Petroleum Exploration and Development
关键词
江汉盐湖盆地
非砂岩
油气运移
油气聚集
Evaporite bed, Oil and gas migration, Mechanism, Mode, Efficiency, Resource extent, Hydrocarbon generating quantity
