f Seismic attenuation measurements from crosshole data

One compelling reason for performing crosshole seismic experiments is that relatively high frequency data are usually obtained compared to surface or VSP surveys. It may seem logical to conclude from this general observation of many published results that the seismic Q of the earth beneath the near surface weathered layer is high . However, in this experiment crosshole seismic data with a, frequency range of 400 to 2500 Hz have been analysed and estimates of the intrinsic Q of sedimentary rocks of approximately 18 have been obtained.