柴达木盆地东部第四系气藏低速异常解释

INTERPRETATION OF THE LOW VELOCITY ANOMALY OF QUATERNARY GAS POOL IN THE EASTERN CHAIDAM BASIN

本文根据低速异常在时间剖面上的表现形态,将其分为三类,对其形成机制进行解释,同时分析圈闭面积大于低速异常面积的原因。文章提出了根据低速异常类型预测气藏级别的方法,以及纵向含气层段预测方法和构造解释方法。针对柴达木盆地东部第四系气藏的具体情况,阐明了低速异常就是寻找天然气藏的直接标志。

The author divides the low velocity anomaly into 3 different types according to its pattern shown on the time section. Its physical mechanism ultimately produced is spelled out. And the reason given rise to the fact that the trapping area covers more extensively than that of low velocity anomaly one is expounded What's more, technique of predicting the size of gas pool depending on the type of low velocity anomaly and forecasting procedure of the longitudinal gas-bearing formational member and approaches used for interpreting the structure are suggested in the paper. Also, with the Quaternary gas pool in eastern Chaidamu Basin as a typical example, the established fact that the low velocity anomaly could be served as an indicator in directly detecting the natural gas is elucidated.