HR: 12:05h
AN: S42B-08    [Abstracts]
TI: The possible statistical relation of Pc1 pulsations to Earthquake occurrence at low latitudes
AU: Bleier, T
EM: tbleier@quakefinder.com
AF: QuakeFinder, 250 Cambridge Ave., Suite 204, Palo Alto, CA 94305, United States
AU: * Bortnik, J
EM: jbortnik@gmail.com
AF: University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90095, United States
AU: Cutler, J W
EM: jwc@stanford.edu
AF: Stanford University, 496 Lomita Mall, Palo Alto, CA 94305, United States
AU: Dunson, C
EM: cdunson@quakefinder.com
AF: QuakeFinder, 250 Cambridge Ave., Suite 204, Palo Alto, CA 94305, United States
AB: It has been suggested in the literature that seismic activity may be preceded by a variety of phenomena, including ultra-low-frequency (ULF) magnetic pulsations, changes in the local ionospheric electron number density, and even geomagnetic activity (in a causal sense or otherwise). In the present study, we test this hypothesis using 8 years of search-coil magnetometer data recorded in Parkfield, California. We use a newly developed identification algorithm to automatically detect and classify all wave events in the Pc1 (0.2-5 Hz) frequency range in our data set, and compare these events to a catalog of local Earthquakes. Pc1 events are believed to be generated in the equatorial magnetosphere, propagate along magnetic field lines to the high latitude ionosphere, and further propagate to low latitudes within the F2-layer ionospheric density duct leaking down to the ground due to the finite conductivity of the E-layer. Thus, we look for changes in detected Pc1 characteristics coincident with Earthquakes, which would act as a proxy for local ionospheric changes. Results of our statistical analysis are presented and discussed in the context of pre-seismic ionospheric modifications.
DE: 2471 Plasma waves and instabilities (2772)
DE: 2487 Wave propagation (0689, 3285, 4275, 4455, 6934)
DE: 6934 Ionospheric propagation (0689, 2487, 3285, 4275, 4455)
DE: 7209 Earthquake dynamics (1242)
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
SC: Seismology [S]
MN: 2007 Fall Meeting