Global variation of body‐wave attenuation in the upper mantle from teleseismic P wave and S wave spectra
نویسندگان
چکیده
[1] We constrain the spatial variation of P‐wave (tP*) and S‐wave (tS*) attenuation by inverting 190,000 teleseismic P‐ and S‐wave spectra up to 0.8 Hz. These spectra are derived from 250 deep earthquakes recorded at 880 broadband global and regional network stations. The variance and ratios of tP* and tS* values are consistent with PREM’s upper mantle velocity and Q structures and conventional tP* and tS* values. High attenuation is resolved beneath stations in tectonically active regions characterized by high heat flow. Low attenuation marks stable continental regions. The maps of tP* and tS* correlate well with the variations of tS* computed and inferred from (1) the most recent surface‐ wave Qmodel and (2) a thermal interpretation of shear‐wave velocity tomography. This indicates that maps of body‐ and surface‐wave attenuation reflect intrinsic attenuation and variable temperature in the mantle. Citation: Hwang, Y. K., J. Ritsema, and S. Goes (2011), Global variation of body‐wave attenuation in the upper mantle from teleseismic P wave and S wave spectra, Geophys. Res. Let t . , 38 , L08311, doi:10.1029/ 2011GL046812.
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