Deterministic seismic microzonation of Kolkata city

作     者：Shiuly, Amit Narayan, J. P. 

作者机构：Indian Inst Technol Roorkee Dept Earthquake Engn Roorkee 247667 Uttar Pradesh India 

出 版 物：《NATURAL HAZARDS》 (自然灾害)

年 卷 期：2012年第60卷第2期

页      面：223-240页

核心收录：

学科分类：07[理学] 0708[理学-地球物理学] 0815[工学-水利工程] 0706[理学-大气科学] 

基　　金：Ministry of Earth Sciences (MoES)  New Delhi [MES-484-EQD] 

主　　题：Seismic microzonation of Kolkata city Ground motion amplification Fundamental frequency and seismic hazard analysis 

摘      要：This paper presents the deterministic seismic microzonation of densely populated Kolkata city situated on the world s largest delta island with very soft and thick soil deposit in the surficial layers. A fourth-order accurate staggered-grid finite-difference algorithm for SH-wave propagation simulation in visco-elastic medium is used for the linear computation of ground motion amplifications in sedimentary deposit. Different maps such as for fundamental frequency (F-0), peak ground acceleration (PGA), peak ground velocity, and peak ground displacement are developed for variety of end-users communities, including structural and geotechnical engineers for performance-based designs, building officials, emergency managers, land-use planners, private businesses, and the general public. The scenario of simulated amplification factors in the different frequency bands revealed that the Kolkata city is very much prone to severe damage even during a moderate earthquake and very selective damage may occur at some of the localities during local and distant earthquakes. The deterministically predicted PGA at bedrock level is 0.0844 g and the maximum PGA predicted at the free surface is 0.6 g in Kolkata city due to maximum credible earthquake (M-w = 5.4) associated with Eocene Hinge Zone at a depth of 36 km. The seismic microzonation of Kolkata city reveals that the Nager Bazar and Nimtala areas are the safest regions with earthquake point of view.