Li Wang
Address: No.163 Xianlin Avenue, Nanjing, China E-mail: li_wang@smail.nju.edu.cn
I am a geophysical Ph.D. candidate in computational seismology laboratory at Nanjing University. My supervisor is Yong Chen， Youyi Ruan and Teh-Ru Alex Song. I am focusing on marine geophysics and volcanology. Recently, I utilized the D/P Ratio method (Ruan et al., JGR, 2014) to derive the temporal variations of S-wave velocity beneath Axial Seamount, a submarine volcano located on the Juan de Fuca Ridge with my supervisors. We found the complex pattern of magma supply and transportation of Axial Seamount's eruption on April 24, 2015, through continuous S-wave changes in the oceanic crust beneath Axial Seamount.
Another work of mine is the application of seismic airgun sources. We took advantage of the high repeatability of a seismic airgun to explore the possibility of monitoring temporal variations of continental crustal velocity.
Volcanic Eruption Process & Magma Transportation of Axial Seamount
Seismic Airgun Application in Urban Areas & Velocity Temporal Variation
Displacement-Pressure Ratio
Displacement-pressure ratio is the admittance between ocean bottom seismometer(OBS)'s vertical displacement and bottom pressure recorder(BPR)'s pressure in the frequency domain.
When the admittance is calculated in the frequency band dominated by fundamental-model Rayleigh wave, it is sensitive to the oceanic crust S-wave velocity.
Through daily or weekly computation of continuous records, we can invert each day or week S-wave velocity by synthetic admittance grid search.
Seismic Airgun Source
Seismic airgun source can generate highly repeatable signals (coherence > 0.95). The repeatability enables the possibility for monitoring temporal variations of crustal velocity. Using measuring crustal velocity at various times through fixed source-station pairs, we could obtain the temporal variations of crustal velocity and correlate these changes with factors like earthquakes, rain, etc.