天然气成藏与保存

On Gas Accumulation and Preservation

天然气成藏是一个天然气聚集与逸散的动态平衡过程,气藏的充注和保存是成藏的两个主要要素。含气盆地的保存因素主要取决于盖层、后期构造运动、气藏形成时间、供气面积和供气强度,大型天然气田的生轻强度一般在20×108m3/km2以上。从整体到局部,采用多方法、多参数全面系统的分析,是正确把握和认识该地区油气勘探潜力的基础。特别强调了压力封闭对天然气成藏与保存的重要作用,同时认为压力体系可作为判断含气盆地是否具有整体封存保存条件的一类重要指标。

Natural gas accumulation is a process of dynamic balance between gas accumulation and gas fugitive emission,in which the inflow and preservation of gas are the key factors for gas reservoir.The preservation of gas-bearing basin primarily depends on its cap rock,late tectonic movement,forming time of gas reservoir,gas supply area and intensity.Normally,a large gas field has its hydrocarbon-generating intensity of over20×108m3/km2.The study shows that from the whole to the local,using multiple methods and parameters for systematic analysis is a foundation of proper hold and understanding of petroleum prospects in an area.This paper stresses the effect of pressure seal on gas accumulation and preservation.The pressure system can be as an important index for discrimination of whether a gas-bearing basin possesses sealing and preservation conditions on the whole or not.