HR: 1400h
AN: S43B-05    [Abstracts]
TI: Evaluation of noise and site effect at MASE stations
AU: * Real-Pérez, J A
EM: jorge8428@yahoo.com.mx
AF: Facultad de Ingeniería, Universidad Nacional Autónoma de México, Cirucuito de Interior s/n, Ciudad Universitaria, Coyoacán, Mexico, DF 04510, Mexico
AU: Pérez-Campos, X
AF: Departamento de Sismología, Instituto de Geofísica, Universidad Nacional Autónoma de México, Cirucuito de la Investigación s/n,Ciudad Universitaria, Coyoacán, Mexico, DF 04510, Mexico
AB: The MesoAmerican Subduction Experiment installed 100 broadband seismic stations along a line between Acapulco and Tampico, crossing Mexico City at its middle point. Its main objective is the modelling of the subduction of the Cocos plate beneath North America. Several studies are being conducted, such as those regarding seismic source, but our objective is to identify site effects and noise levels and its sources at MASE stations, in order to evaluate the site and signal quality. We observe that most of the sites have noise levels within those from Peteterson (1993). At all stations the tide noise is clear. For those stations closer to the coast, the noise from the ocean waves is clear. Those installed within cities, large towns or close to the freeway have a difference in noise levels between day and night, either at a specific frequency or within a frequency range. Almost all of the MASE stations show some site effect, which is mainly a consequence of the criteria used in the site selection, since its location with respect to the line, security of the equipment, access to the station and line of sight (for those that transmit in real time) had a higher priority than the site quality itself. Therefore, most of the stations show an amplification at high frequencies (>1 Hz), and some have a resonant frequency. Despite the large site effect, few of them show poor noise levels, and on the contrary, a few with little site effect, show large noise levels, particularly during the day. Our results will benefit other studies that need to be able to take into account site effects and signal to noise ratio for their particular objectives, in order to select optimal stations and/or signals.
DE: 7200 SEISMOLOGY
DE: 7294 Seismic instruments and networks (0935, 3025)
SC: Seismology [S]
MN: 2007 Joint Assembly