The Strong Motion Amplitudes from Himalayan Earthquakes and A Pilot Study for the Deterministic First Order Microzonation of Delhi City
IR@C-MMACS: CSIR-Centre for Mathematical Modelling and Computer Simulation, Bangalore
View Archive Info| Field | Value | |
| Title |
The Strong Motion Amplitudes from Himalayan Earthquakes and A Pilot Study for the Deterministic First Order Microzonation of Delhi City
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| Creator |
Parvez, Imtiyaz A
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| Subject |
Computational Seismology
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| Description |
The interdependence among the strong-motion amplitude, earthquake magnitude and hypocentral distance has been established (Parvez et al. 2001) for the Himalayan region using the dataset of six earthquakes, two from Western and four from Eastern Himalayas (Mw =5.2-7.2) recorded by strong-motion networks in the Himalayas. The level of the peak strong motion amplitudes in the Eastern Himalayas in three fold larger than that in the Western Himalayas, in terms of both peak acceleration and peak velocities. In the present study, we include the strong motion data of Chamoli earthquake (Mw=6.5) of 1999 from the western sub-region to see whether this even supports the regional effects and we find that the new result fits well with our earlier prediction in Western Himalayas. The minimum estimates of peak acceleration for the epicentral zone of Mw =7.5-8.5 events is Apeak=1.0-1.6g for the Eastern Himalayas. Similarly, cm/s for Eastern Himalayas. The presence of unusually high levels of epicentral amplitudes for the eastern subregion also agrees well with the macroseismic evidence (Parvez et al. as a basis for future regionalized seismic hazard assessment in the Himalayan region.
Many metropolitan and big cities of India are situated in the severe hazard zone just south of the Himalayas. A detailed microzonation study of these sprawling urban centres is therefore urgently required for gaining a better understanding of ground motion and site effects in these cities. An example of the study of site effects and microzonation of a part of metropolitan Delhi is presented based on a detailed modelling along a NS cross sections from the Inter State Bus Terminal (ISBT) to Sewanagar. Full synthetic strong motion waveforms have been computed using the hybrid method, a combination of modal summation and finite difference techniques, for the earthquake source of July 15, 1720 (MMI=IX, M=7.4), and mapped all along the cross section. The response spectra ratio (RSR), i.e. the response spectra computed from the signals synthesized along the laterally varying section normalized by the response spectra computed from the corresponding signals, synthesized for the bedrock reference regional model, have been determined as well.
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| Publisher |
The Abdus Salam International Centre for Theoretical Physics, Italy
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| Date |
2001-09
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| Type |
Monograph
NonPeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://cir.cmmacs.ernet.in/262/1/IC%202001%20130.pdf
Parvez, Imtiyaz A (2001) The Strong Motion Amplitudes from Himalayan Earthquakes and A Pilot Study for the Deterministic First Order Microzonation of Delhi City. Project Report. The Abdus Salam International Centre for Theoretical Physics, Italy, The Abdus Salam International Centre for Theoretical Physics. (Unpublished) |
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| Relation |
http://cir.cmmacs.ernet.in/262/
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