Small scale hot upwelling near the North Yellow Sea of eastern China

In order to image the structure of the upper-mantle discontinuity beneath Eastern China, we have applied a common conversion point (CCP) stacking method of receiver function (RF). Both the 410-km and the 660-km discontinuities (hereafter called the 410 and the 660) clearly show continuous positive phases along the selected profile. The 410 shows depression, whereas the 660 shows uplift, in the eastern section of the study profile. The transition zone (TZ) to the west of longitude 122 degrees is thicker than the global average, though the TZ is thinner to the east of that longitude. The thinnest part of the TZ, with 10 similar to 15 km of thinning (an increase in temperature of up to 100 degrees C), is located at the North Yellow Sea. We suggest that either the small-scale convection associated with the deep penetration of the sinking slab into the lower mantle, or a small plume from lower mantle, has generated hot upwelling in this region. Citation: Ai, Y., T. Zheng, W. Xu, and Q. Li (2008), Small scale hot upwelling near the North Yellow Sea of eastern China, Geophys. Res. Lett., 35, L20305, doi: 10.1029/2008GL035269.