表层速度极低对静校正的影响分析

Analysis of the Very Low Weathered layer Velocity for Static Correction

在精细表层结构调查工作中,微测井求取个别点的表层速度极低,达到200~300m/s,低于空气中声波速度340m/s,与基本认识不相符。针对这一问题进行理论分析,结合实际资料验证,找出了原因。通过模型正演验证,表明表层速度极低不会对静校正工作产生直接影响,但如果忽视了表层速度极低的存在,则在资料的处理和解释过程中会出现假断层等构造现象。

In the detailed investigation of surface structure,the weathered layer velocity of individual points obtained by micro logging is very low,reaching 200~300m/s,lower than the acoustic velocity 340 m/s in the air,which is not consistent with the basic knowledge.To solve this problem,this paper carries on the theoretical analysis,and verifies the reason with the actual data verification.The forward model validation indicated that the weathered layer velocity is extremely low.It doesn't have a direct impact on the static correction,but if ignoring the very low weathered layer velocity,then there will be false faults in data processing and interpretation.