A velocity model perpendicular to the Acapulco trench based on resmac data
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Abstract
The interpretation of seismic phases observed in records from the Mexican Continental Aperture Seismic Network (RESMAC), by means of differences in travel times and ray tracing, was used to test two currently used bidimensional velocity models for the Acapulco Trench (southern Mexico) region. The models were found to be inadequate to explain the observations; hence, a new model "MEXD" was developed. The MEXD model features a 40 km thick continental crust represented by horizontal, parallel, constant velocity layers, and a 24 km thick layer dipping with an angle of 13° in the N20°E direction, that represents the subducted oceanic crust.
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