The delhi 1960 earthquake: Epicentre, depth and magnitude
Por:
Singh S.K., Suresh G., Dattatrayam R.S., Shukla H.P., Martin S., Havskov J., Pérez-Campos X., Iglesias A.
Publicada:
25 oct 2013
Categoría:
Multidisciplinary
Resumen:
Though the Delhi earthquake of 27 August 1960 is important in understanding seismic hazard to the city, there is large uncertainty associated with its reported epicentre, depth and magnitude. The reported epicentres given in different catalogues are not consistent with felt and damage reports, and the depths (58-109 km) are also inconsistent with recorded waveforms (including the excitation of Lg waves), decay of seismic intensities with distance, number of aftershocks, earthquake sound and seismotectonics of the region. The reported magnitude of the earthquake varies between 5.3 and 6.0. We have performed an exhaustive analysis of the available information, including comparison of the seismograms of the 1960 earthquake with six recent well-recorded events as well as with the Moradabad earthquake of 1966. We find that: (1) A more reliable epicentre as compared to the instrumentally determined one, is provided by the locus of the strongest seismic intensity: 28.47°N, 77.00°E (between Delhi Cantonment and Gurgaon). (2) The earthquake was shallow (depth = 30 km, but most likely = 15 km). (3) The magnitude of the earthquake was Mw 4.8 (range Mw 4.6-4.9). The seismic intensity is also consistent with Mw < 5.0. We conclude that the Delhi 1960 earthquake occurred between Delhi Cantonment and Gurgaon, it was shallow and its magnitude was 4.8, significantly less than M 6.0 often used in studies dealing with hazard in the city.
Filiaciones:
Singh S.K.:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
Suresh G.:
India Meteorological Department, Lodi Road, New Delhi 110 003, India
Dattatrayam R.S.:
India Meteorological Department, Lodi Road, New Delhi 110 003, India
Shukla H.P.:
India Meteorological Department, Lodi Road, New Delhi 110 003, India
Martin S.:
Victoria University of Wellington, School of Geography, Environment and Earth Sciences, Wellington, New Zealand
Havskov J.:
Department of Earth Sciences, University of Bergen, Bergen, Norway
Pérez-Campos X.:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
Iglesias A.:
Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico
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