地震速度谱资料预测地层压力的陷阱分析

地震层速度谱可以较好地反映快速沉积过程中形成的欠压实地层产生的超压现象。由于地震速度谱资料本身存在误差，又受分辨率的限制，应用地震速度谱资料预测地下地层压力具有多解性；受地下地层变化和构造复杂等因素的影响，预测结果的稳定性较差。通过对已经完钻的100多口预探井地层压力与地震速度谱资料预测结果进行对比分析，研究在实际应用中由于地层年代、地质构造、地震多次波和断面波等因素产生的干扰，总结出应用速度谱资料预测地层压力时的一些常见陷阱，制定了速度谱资料一般校正准则，增加地层压力预测结果的可靠性，减少其随机性。

Pitfalls in prediction of formation pressure using seismic velocity.

Seismic velocity can faithfully reflect the formation o-verpressure phenomenon in undercompacted formations produced by rapid formation subsidence. However, the estimated formation pressure from seismic velocity data is not unique due to the errors and limited resolution of the velocity spectrum, and is also unstable owing to complex structures. Through the correlation between formation pressure and seismic velocity spectrum over more than 100 preliminary prospecting wells, we studied the major factors affecting the prediction,such as stratigraphic time,geological structure, seismic multiples,and waves from fractured surface, summarized some common pitfalls in using velocity spectrum to predict formation pressure, and developed some criteria for correction of velocity spectrum.