Integrated Deterministic and Stochastic Full-Waveform Earth Models for Broadband Wave Propagation and Prediction
Abstract
This is a contract to develop integrated deterministic and stochastic models to better predict broadband waveforms. We took a comprehensive, three-pronged approach: (1)Computational Methods. We implemented a new and efficient algorithm for simulating wave propagation in an elastic media and developed a new passive-source reverse-time migration method. These new methods enable us to separate intrinsic attenuation from scattering attenuation and image scatterers and discontinuities. (2)Full-wave Tomography. We carried out a full-wave Pn tomography of the central and northern Tibetan plateau. To our knowledge, this is the first full-wave Pn tomography, which extends the traditional 2D Pn model to fully 3D. We calculated full-wave sensitivity kernels of Z/H Rayleigh wave amplitude ratios to better constrain the velocity and density structures of the crust and shallow mantle. We developed a joint gravity and full-wave seismic inversion and applied it to southern California. (3)Stochastic Models. We showed that small-scale heterogeneities have significant effects on travel times and amplitudes. We observed that the power spectral densities (PSDs) of the resolved spectra of western U.S., the local tomographic models and the stochastic model from modeling of scattered waves follow a linear trend consistent with the power-law distribution.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 21, 2018
- Accession Number
- AD1070926
Entities
People
- Xueyang Bao
- Yang Shen
Organizations
- University of Rhode Island