Low seismicity in the Bhutan Himalaya and the stress shadow of the 1897 Shillong Plateau earthquake

Abstract The seismicity of the Bhutan Himalaya region is generally low as compared to its adjoining Himalayan segments. The topography in the region is slightly subdued and different from the neighbouring central Nepal region. Low seismicity in the region may possibly be due to the postulated low convergence rate in the Bhutan Himalaya, difference in subsurface structures, or the aseismic nature of the region. We suggest that the lower seismicity in the Bhutan Himalaya may also be due to stress change caused by the great 1897 Shillong Plateau earthquake as the low seismicity region of the Bhutan Himalaya coincides with the stress shadow of the earthquake.

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