Finite-Frequency Seismic Tomography of Body Waves and Surface Waves from Ambient Seismic Noise: Crustal and Mantle Structure Beneath Eastern Eurasia
Abstract
To improve seismic calibration for nuclear explosion monitoring, we use 3D sensitivity kernels of finite-frequency body and surface waves to develop models of the crustal and mantle structures beneath eastern Eurasia. We have collected and processed available broadband data from both permanent stations and temporary networks in eastern Eurasia. We obtained a regional P-wave velocity model for the mantle structures down to 1,500 km beneath the eastern Eurasia. We also carried out a detailed study of the P- and S-wave velocity structures in southeastern Tibet, which led to some interesting geological findings. Our P- and S-wave velocity models reveal a low-velocity anomaly in the crust and upper mantle to ~300 km depth beneath a north-south-trending rift zone in southeastern Tibet. This low-velocity anomaly is situated above a tabular, high- dipping-angle, high-velocity anomaly that extends into the upper-mantle transition zone. These results are evidence for the delamination of the mantle lithosphere and its causal relationship to the formation of the north-south trending rift in southeastern Tibet.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2008
- Accession Number
- ADA487647
Entities
People
- Ting Yang
- Wei Zhang
- Xiaoping Yang
- Yang Shen
- Yong Ren
Organizations
- Leidos