Empirical Constraints on Broadband Array Designs
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Empirical Constraints on Broadband Array Designs Charles A. Langston Center for Earthquake Research and Information University of Memphis
description
Empirical Constraints on Broadband Array Designs. Charles A. Langston Center for Earthquake Research and Information University of Memphis. Outline. Broadband array designs – IRIS 2012 meeting Using TA to answer: How coherent are teleseismic body waves?. Array Design Criteria. - PowerPoint PPT Presentation
Transcript of Empirical Constraints on Broadband Array Designs
Empirical Constraints on Broadband Array Designs
Charles A. LangstonCenter for Earthquake Research and Information
University of Memphis
Broadband array designs – IRIS 2012 meeting
Using TA to answer: How coherent are teleseismic body waves?
Outline
Array Design CriteriaStation spacing Array Diameter
Wave Correlation Distance(as determined from regional arrays)
Sierpinski Gasket Fractal D=1.58
Is
For teleseismic body waves?Important for: Array Design Transfer function analysis
Use TA to get basic data on wave coherency
449 Vertical P Waves
Correct for instrument response
Procedure
Fixed time windows -30s to +90s after IASPEI91 P wave arrival time -60s to +120s after IASPEI91 S wave arrival
time
Time window inversely proportional to band pass center frequency
Two Analyses
Teleseismic vertical P waveforms show the highest coherence with interstation distance supporting both large aperture, broadband teleseismic array experiments and stacking strategies for receiver functions.
S waves also show reasonable coherence supporting construction of useful large arrays.
Coherence is somewhat degraded for propagation through the upper mantle.
Conclusions
