Slide 1

Large Earthquake Rupture Imaging Using the Back-Projection Technique and Improving the Array Response Function

Student Researcher: Kevin KwongThesis Advisor: Keith Koper

Ishii et al. 2005Imaging Earthquake Rupture From Back-Projecting Body WavesThe back-projection method traces seismic waves back to their original rupture source.

We use specifically teleseismic P waves

We locate sources of rupture by looking at regions in space and time that show relative high amplitudes

Back-projection imaging resolve important rupture parameters and details that can be used to inform public and tsunami warning systems

Peter Shearer 2009Ishii 2011Resolving Complex Rupture Details

We stack the seismograms and sum the energy to a beam to resolve local maximum energy releasing peaks

Koper et al., 2011Imaging ArtifactsArtifacts in time and space can complicate back-projection images

The smearing and leakage of energy in space and time is a big concern that relates in how the array distorts the image and results in a less optimal Array Response Function (ARF)

IRIS back projection results for 2010 Chile eventMitigating ArtifactsWe will devise methods to suppress imaging artifacts and deconvolve back-projection images

Looking at artifacts in back-projected aftershock events

Station weighting for resolving optimal array response functions

Keith Koper , Personal Communication