COMPARISON OF SEISMIC ATTENUATION IN THE GERMAN KTB AND IN THE RUSSIAN KOLA DEEP-WELL

Attenuation estimations from vertical seismic profile (VSP) data measu red in the German KTB (Continental Deep Drilling Program) have shown l ow Q-values in the uppermost crystalline crust down to 6 km. These low Q-values correspond to the results obtained for crystalline rocks in other parts of the world, and are supported in this paper by new resul ts of seismic attenuation estimated from VSP data measured in the Russ ian Kola SG-3 super-deep well located on the Kola Peninsula. The spect ral-ratio method is used, with a slight modification In the seismic fr equency band below 100 Hz, seismic attenuation in both areas shows a n early linear dependence on frequency, i.e., Q is independent of freque ncy.