THREE-DIMENSIONAL SHEAR-WAVE QUALITY FACTOR, QS(F), MODEL FOR SOUTH-CENTRAL GULF OF CALIFORNIA, MEXICO OBTAINED FROM INVERSION OF BROADBAND DATA
Por:
Kumar, Sanjay, Joshi, Anand, Castro, Raul R., Singh, Shri K., Singh, Sandeep
Publicada:
1 abr 2021
Resumen:
We apply an iterative inversion scheme, initially developed by Hashida
and Shimazaki (1984) and later modified by Joshi et al., (2010), to
estimate three - dimensional shear - wave quality factor, Q(s)(f), of
south-central Gulf of California, Mexico. An area of 230 km x 288 km in
this region is divided into 108 rectangular blocks of different Q(s)(f).
We use 25 well-located earthquakes recorded at three broadband stations
of the regional network RESBAN operated by CICESE (Centro de
Investigacion Cientifica y de Educacion Superior de Ensenada, Baja
California) and three Ocean Bottom Seismographs (OBS) of the Sea of
Cortez Ocean Bottom Array (SCOOBA) experiment. This dataset permits us
to obtain Q(s)(f) estimates of different blocks using the modified
inversion algorithm. Q(s)(f) is obtained at various frequencies in 0.16
similar to 8.0 Hz range. We found that the estimated Q(s) structure
correlates with geological and tectonic models of the region proposed in
previous studies. A regional frequency-dependent relation using all 1944
values of shear-wave quality factor is obtained at 18 different
frequencies in all blocks can be approximated by a function of the form
Q(s)(f) = 20 f(1.2). This relation is typical in a tectonically active
region with high S-wave attenuation and is similar to attenuation
relations reported by other authors for the Imperial Valley, California
region.
Filiaciones:
Kumar, Sanjay:
Kumar, S (Corresponding Author), Indian Inst Technol Roorkee, Dept Earth Sci, Roorkee, Uttar Pradesh, India. Kumar, Sanjay
Joshi, Anand:
Kumar, S (Corresponding Author), Indian Inst Technol Roorkee, Dept Earth Sci, Roorkee, Uttar Pradesh, India. Kumar, Sanjay
Singh, Sandeep:
Kumar, S (Corresponding Author), Indian Inst Technol Roorkee, Dept Earth Sci, Roorkee, Uttar Pradesh, India. Kumar, Sanjay
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