盖层与源岩的时空配置关系对油气运聚成藏的控制作用

盖层与源岩是油气成藏不可缺少的两个条件，它们在时空上的配置关系对油气运聚成藏起着重要的控制作用，盖层的空间分布面积只有大于源岩的空间分布面积时，盖层才能封闭住源岩排出的大量油气，尤其覆盖整个盆地或凹陷时效果更好；否则造成油气大量散失，不利于油气的大量聚集与保存，盖层封闭能力形成期只有早于或与其相当时，才能封闭住源岩排出的大量油气，有利于油气的大规模聚集成藏，反之，盖层所能封闭住油气量的大小主要取决于两者之间时间差的相对大小，两者时间差越大，盖层所能封闭住油气量的大小主要取决于两者之间时间差的相对大小，两者时间差越大，盖层所能封闭住源岩排出的油气量相对越小，不利于油气的大相对大小，两者时间差越大，盖层所能封闭住源岩排出的油气量相对越小，不利于油气的大规模聚集成藏；反之，盖层所能封闭住源岩排出的不同气量相对越大，越有利于油气的大规模聚集成藏。

CONTROLLING EFFECT OF MATCH RELATION BETWEEN CAPROCK AND SOURCEROCK IN TIME AND SPACE ON FORMATION OF OIL OR GAS POOLS

Caprock and sourcerock are two indispensable conditions for formation of oil or gas pools. Match relation between caprock and sourcerock in time and space plays an important role in forming oil or gas pools . Only when space distribution area of caprock is bigger than that of sourcerock, can caprock seal all the oil or gas from sourcerock. Especially when caprock distributes over all the basin or sag, the effect of caprock on sealing oil or gas from sourcerock is best. If not, a great deal of oil or gas from sourcerock will be lost.It is not favorable for oil or gas to accumulate and preserve. Only when the formation period of sealing ability of caprock is earlier than the period of a great deal of oil or gas expelled from sourcerock or they are the same period,can caprock seal all the oil or gas from sourcerock, It is favorable for oil or gas to accumulate and preserve. If not , oil or gas amount sealed by caprock is controlled by the time difference between the formation period of sealing ability of caprock and the period of a great deal of oil or gas expelled from sourcerock, The bigger the time difference is, the smaller the oil or gas amount sealed by caprock is. It is not favorable for oil or gas to accumulate and preserve. If not, the smaller the time difference is,the bigger the oil or gas amount sealed by caprock is. It is favorable for oil or gas to accumulate and preserve.