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Martynov, VG, Vernon FL, Mellors RJ, Pavlis GL.  1999.  High-frequency attenuation in the crust and upper mantle of the northern Tien Shan. Bulletin of the Seismological Society of America. 89:215-238. AbstractWebsite

We analyze 243 three-component broadband digital seismograms of aftershocks from the M-s = 7.3 Suusamyr, Kyrgyzstan, earthquake to determine seismic attenuation in the northern Tien Shan. P-g, S-g, and SmS body waves and 5' coda waves were used to estimate the frequency-dependent (f = 1.2-30 Hz) attenuation and scattering parameters of the crust and upper mantle as a function of depth. Using the equation Q(f) = Q(0)f(n) multiple layers, we find that Q(0) increases with depth from 76 (upper crust) to 1072 (upper mantle), and the value of n decreases from 0.99 to 0.29 over the same ranger The Q coda results also demonstrated an azimuthal dependence: Q(0) = 736 in the north-south direction and Q(0) = 494 in the east-west direction. There is a strong 2 phi dependence on azimuth for high frequencies (>1.2 Hz). The depth and azimuthal dependence of the quality factor show that the Q is complicated and three dimensional. Estimates of the inhomogeneity scale a show two types of multiple scatterers (Wu and Aki, 1985): a velocity perturbation with a = 0.5-3.0 km and an impedance perturbation with a = 0.052-0.413 km. It appears that a increases with depth. The coefficient of scattering decreases from [g(0)](f) = 0.0055 km(-1) at h = 0-6 km to 0.0020 km(-1) at h = 6-11 km and 0.0048 km(-1) at h = 11-15 for forward scattering and [g(pi)](f) = 0.0006 km(-1) at depth of low crust and upper mantle for backscattering. Estimates off seismic albedo B-0 show that the primary source of attenuation is intrinsic anelasticity, and the variation of Q(0) and n indicates that the level of heterogeneity varies with depth, possibly due to pressure. The lateral variation of Q(0) can be connected with azimuthal anisotropy in the upper mantle related to current deformation under the Tien Shan.

Given, HK, Tarasov NT, Zhuravlev V, Vernon FL, Berger J, Nersesov IL.  1990.  High-Frequency Seismic Observations in Eastern Kazakhstan, USSR, with Emphasis on Chemical Explosion Experiments. Journal of Geophysical Research-Solid Earth and Planets. 95:295-307.   10.1029/JB095iB01p00295   Website
Berger, J, Orcutt J, Vernon F.  2005.  HiSeasNet: Providing Internet to the UNOLS fleet. Sea Technology. 46:17-20.Website