Improved Characterization of Far-Regional and Near-Teleseismic Phases Observed in Central Asia
Abstract
The early body-wave coda of far-regional events (14 - 29 degrees) contains triplicated arrivals from upper-mantle discontinuities that could potentially improve seismic monitoring capabilities. However, far-regional seismograms are typically under-utilized in location and magnitude estimation because path-specific heterogeneity and multiple phase interactions make the arrival suite difficult to interpret accurately. In this report we present a set of techniques that were developed to improve phase characterization and identification at these distances. We have applied our techniques to data from two arrays in Kazakhstan: MKAR (Makanchi) and KKAR (Karatau), both of which record far-regional events throughout south-central Asia. Our techniques include improved array processing methods (e.g., phase-coherence semblance stacking) to characterize arrival time, back-azimuth and slowness of individual phases within the P-coda arrival suite, and methods to more accurately identify the measured arrivals (e.g., -p transformation and clustering analysis to determine wavefield templates).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 02, 2010
- Accession Number
- ADA526182
Entities
People
- Aaron Ferris
- Anastasia Stroujkova
- Delaine Reiter
- Katherine Murphy