High-resolution separation of earthquake phases using sparsity-promoting polarization filtering method
عنوان دوره: بیستمین کنفرانس ژئوفیزیک ایران
کد مقاله : 2051-NIGS
نویسندگان
1موسسه ژئوفیزیک دانشگاه تهران
2Department of computer Sciences, University of Beria Interior
3Instute of Earth Sciences Jaume Almera
چکیده
The extraction of body waves from seismic wave fields has always been a significant interest in the seismological community. Their study provides a picture of the Earth's crust, upper mantle, and critical continuities such as the Moho Transition Zone (e.g., 410 km and 660 km depth). In addition, it provides information for determining the source mechanism of earthquakes. However, due to their intrinsic weaker amplitude than other seismic waves, they are usually masked by surface waves. Their detection and extraction require advanced analysis and processing tools and methods. This study uses the sparsity-promoting polarization filter method to extract body waves from earthquake waveforms, exploiting their polarization properties in the time-frequency (TF) domain. The computed rectilinearity, directivity, and amplitude attributes calculated from the TF-domain polarization map of earthquake signals are used to discriminate between body and surface waves. Synthetic data examples show the performance of the proposed earthquake phase separation method.
کلیدواژه ها
body wave؛ adaptive time-frequency filtering؛ earthquake waveform؛ polarization analysis؛ sparsity promoting
Title
High-resolution separation of earthquake phases using sparsity-promoting polarization filtering method
Authors
Bahare Imanibadrbani, Ahmad Sadidkhouy, Hamzeh Mohammadigheymasi, Ali Gholami, Martin Schimmel
Abstract
The extraction of body waves from seismic wave fields has always been a significant interest in the seismological community. Their study provides a picture of the Earth's crust, upper mantle, and critical continuities such as the Moho Transition Zone (e.g., 410 km and 660 km depth). In addition, it provides information for determining the source mechanism of earthquakes. However, due to their intrinsic weaker amplitude than other seismic waves, they are usually masked by surface waves. Their detection and extraction require advanced analysis and processing tools and methods. This study uses the sparsity-promoting polarization filter method to extract body waves from earthquake waveforms, exploiting their polarization properties in the time-frequency (TF) domain. The computed rectilinearity, directivity, and amplitude attributes calculated from the TF-domain polarization map of earthquake signals are used to discriminate between body and surface waves. Synthetic data examples show the performance of the proposed earthquake phase separation method.
Keywords
body wave, adaptive time-frequency filtering, earthquake waveform, polarization analysis, sparsity promoting