HR: 1340h
AN: T33C-1400    [Abstracts]
TI: Crustal Structure of Southern Baja California Peninsula, Mexico, From Magdalena Microplate to Farallon Basin
AU: * Robles, L N
EM: robles@cicese.mx
AF: Centro de Investigacion Cientifica y Educacion Superior de Ensenada, Km 107 Tijuana-Ensenada, Ensenada, BC 22830 Mexico
AU: Gonzalez-Fernandez, A
EM: mindundi@cicese.mx
AF: Centro de Investigacion Cientifica y Educacion Superior de Ensenada, Km 107 Tijuana-Ensenada, Ensenada, BC 22830 Mexico
AU: Fletcher, J M
EM: jfletche@cicese.mx
AF: Centro de Investigacion Cientifica y Educacion Superior de Ensenada, Km 107 Tijuana-Ensenada, Ensenada, BC 22830 Mexico
AU: Lizarralde, D
EM: danl@eas.gatech.edu
AF: Georgia Tech, School of Earth and Atmospheric Sciences, Atlanta, GA 30332 United States
AU: Kent, G M
EM: gkent@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093 United States
AU: Harding, A J
EM: aharding@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093 United States
AU: Holbrook, W S
EM: steveh@uwyo.edu
AF: University of Wyoming, Department of Geology and Geophysics, Laramie, WY 82071 United States
AU: Umhoefer, P J
EM: paul.umhoefer@nau.edu
AF: Northern Arizona University, Department of Geology, Flagstaff, AZ 86011 United States
AU: Axen, G J
EM: gaxen@ess.ucla.edu
AF: University of California Los Angeles, Department of Earth and Space Sciences, Los Angeles, CA 90095 United States
AB: Wide-angle seismic data were used to investigate the crustal structure of a transect between the Magdalena Microplate to the Farallon Basin in the Gulf of California, crossing the southern Baja California Peninsula to the north of La Paz (Mexico). This is the first deep seismic study in the area, providing information of the fossil subduction zone of the Magdalena Microplate under Baja California. We have also obtained results of the seismic structure of major fault zones in the area such as Tosco-Abreojos and Santa Margarita. Seismic data were recorded by Ocean Bottom Seismometers (OBS) in the Pacific and the Gulf of California and by portable seismic instruments onshore. More than 5000 offshore high-volume air gun shots were used as energy source in both sides of the Peninsula. Wide-angle data were processed to enhance the signal to noise ratio to help in the identification of the seismic energy arrivals. We used a direct method of interpretation, including ray tracing, travel times and synthetic seismograms calculation. The availability of a number of recording instruments allows multiple coverage of the crustal structure.
DE: 9350 North America
DE: 9355 Pacific Ocean
DE: 7220 Oceanic crust
DE: 7205 Continental crust (1242)
DE: 3025 Marine seismics (0935)
SC: Tectonophysics [T]
MN: 2004 AGU Fall Meeting