报告地点:教学行政楼 706 会议室
报告时间:2024-09-20 从 14:00 到 16:30
报告人:H. Thybo(SinoProbe Laboratory, CAGS, Beijing, China; Eurasia Institute of Earth Sciences, Istanbul Technical University, Turkey; School of Earth Sciences, China University of Geosciences Wuhan, China)
报告人简介:
Hans Thybo是国际知名的地球物理学家,为欧洲科学院院士,丹麦皇家科学院院士和挪威科学院院士。目前担任国际岩石圈委员会主席,Earth Planetary Science Letters (EPSL)期刊主编。他共同创立了欧洲地球科学联合会(EGU)并曾担任主席。
报告题目:Fine Scale Seismic Heterogeneity in the Crust and Mantle: Observation and Interpretation
Pronounced seismic heterogeneity in the interior of the Earth is detected and imaged with high-resolution seismic data from controlled source seismology acquired with dense station spacing and at high frequency, such as the Sovjet Peaceful Nuclear Explosion (PNE) data set. This data can focus on details at selected depth intervals. Mantle body waves indicate pronounced heterogeneity at four depth levels, whereas other depth intervals appear transparent at the considered frequency band of 0.5-15 Hz. We model characteristic scale lengths and velocity contrasts by application of 2D Finite Difference simulation of seismic wave propagation. This talk will discuss teleseismic Pn wave identified in cratonic regions, the Low-Velocity Zone (LVZ) in the lithosphere mantle, significant scattering from around the top of the Mantle Transition Zone, and seismic high-frequency reflections (up-to 4.5 Hz) observed from the Core-Mantle Boundary (CMB), respectively.