Determining the focal mechanisms of earthquakes by full waveform modeling

Determining the focal mechanism of an earthquake helps us to better characterize reservoirs, define faults, and understand the stress and strain regime. The objective of this thesis is to find the focal mechanism and depth of earthquakes. This objective is met using a full waveform modeling method in which we generate synthetic seismograms using a discrete wavenumber code to match the observed seismograms. We first calculate Green's functions given an initial estimate of the earthquake's hypocenter, the locations of the seismic recording stations, and the velocity model of the region for a series of depths with intervals of 1 km. Then, we calculate the moment tensor for 6840 different combinations of strikes, dips, and rakes for each of those depths. These are convolved with Green's function and with an assumed smooth ramp source time function to produce the different synthetic seismograms corresponding to the different strikes, dips, rakes, and depths.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Busfar, Hussam A. (Hussam Abdullah)

Advisor dc:contributor.advisor

• M. Nafĭ Toksöz.

• Earth, Atmospheric, and Planetary Sciences.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/53105

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/53105