地震勘探中平均速度的求取方法及应用

针对地震数据处理和资料解释过程中经常用到地层的平均速度,而平均速度的求取不易,尤其在测井资料很少的情况下,平均速度的求取更难等问题.依据地震勘探原理,在中、浅层地震勘探中,可将沉积地层近似为连续介质的地质模型,在连续介质中速度随深度的变化存在一定规律,不同地区有不同的经验公式,应用均方根速度在连续介质情况下的近似公式及数据处理中所得到的速度谱资料能够计算出平均速度的经验公式,得出的平均速度能够满足中、浅层地震勘探中时深转换的需要,另外,应用平均速度及钻孔资料可以对地震时间剖面进行相位标定.

Calculation method of average velocity in seismic exploration and its application

In seismic data processing and data interpretation process,the average velocity in strata is a commonly used datum.Calculating the average velocity is not easy,in particular,in the situation of lack of logging data.Based on the principle of seismic exploration,in shallow seismic exploration,the sedimentary formations can be regarded as a continuum medium in geological model.In a continuous medium,the wave velocity varies with depth increase.Normally,different regions have their different empirical formula.Using RMS velocity in continuous medium and velocity spectrum in data processing,an empirical formula can be obtained for calculating the average wave velocity.The average wave velocity calculated can meet the requirement in shallow seismic exploration.In addition,the average wave velocity and borehole data can be used in the calibration of seismic time profiles and phase.