Crustal structure and magmatic evolution in the Pearl River Delta of the Cathaysia Block: New constraints from receiver function modeling
We used teleseismic data recorded at 17 permanent seismic stations operated by the China Earthquake Administration. Teleseismic waveforms from events with magnitudes ≥ 6.0 and with epicentral distances of 30° to 90° were chosen to estimate receiver functions beneath the stations. The earthquakes mainly occurred along the Kurile and Aleutian island arcs, north of Australia, Indonesia and the Tibet continental collision zone. The seismograms were manually checked to extract the data with high signal-to-noise ratio. The traces were windowed to include 30 s before and 100 s after the direct P-wave arrivals, and then horizontal components were rotated into radial and transverse components. We computed receiver functions using the source equalization procedure with a water-level parameter of 0.001 and a Gaussian width of 2.5. The final receiver functions were further checked based on noise level of the signals before the direct P-wave arrivals as well as the shape of the following converted phases.