Uppermost Mantle Structure in the Middle East, Central Asia, Lake Baikal, and FarEast from Pn Tomography and Sn Attenuation

摘要

We have studied the propagation efficiencies of the Sn and Lg phases throughoutChina and produced summary maps. In addition, estimates of coda Q, Q for the Pn phase, and Q for the Lg phase for Tibet have been made. Sn has difficulty propagating across extended terrains in eastern China, the northern Tibetan plateau, and Mongolia. This makes it a difficult phase to use for nuclear monitoring purposes. Analysis of the Pn and Lg Q for northern Tibet show that partial melt both in the uppermost mantle and middle crust quickly attenuate these phases. Lg does propagate well over most of the rest of China, especially when it does not traverse major changes in crustal structure.