Abstract
The upper crustal (≤20 km)P-wave velocity beneath the Shillong Plateau and Nowgong area has been studied by the time-distance plot method. TheP-arrival data of the shallow (≤20 km) microearthquakes from three temporary networks are used, and the average velocity is found to be 5.55 km/s. The velocity ratio (V p /V s ) for the upper crust (0–20 km) as well as for the lower crust (21–40 km) are determined by the Wadati-plot method and station-by-station method. The average value obtained by the two methods is compatible; theV p /V s ranges between 1.74 to 1.76. A generalized seismic velocity model of the area is suggested by this study, which has been very useful for microearthquake location.
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De, R., Kayal, J.R. CrustalP-wave velocity and velocity-ratio study in northeast India by a microearthquake survey. PAGEOPH 134, 93–108 (1990). https://doi.org/10.1007/BF00878082
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DOI: https://doi.org/10.1007/BF00878082