Abstract
In the aftermath of the 2004 Indian Ocean (Sumatra-Andaman) tsunami, numerous survey teams investigated its effects on various locations across the Indian Ocean. However, these efforts were focused only on sites that experienced major destruction and a high death toll. As a consequence, some Indian Ocean coastal megacities were not examined. Among the cities not surveyed was Mumbai, the principal west coast port and economical capital of India with a population of more than 12 million. Mumbai is at risk of tsunamis from two major subduction zones in the Indian Ocean: The Sumatra-Andaman subduction zone (SASZ) and the Makran subduction zone (MSZ). As a part of the present study, we conducted a field survey of the 2004 Indian Ocean tsunami effects in Mumbai, analysed the available tide gauge records and performed tsunami simulations. Our field survey in 2018 January found run-up heights of 1.6-3.3 m in the Mumbai area. According to our analysis of tide gauge data, tsunami trough-To-crest heights in Okha (550 km to the north of Mumbai) and in Mormugao (410 km to the south of Mumbai) were 46 cm and 108 cm, respectively. Simulations of a hypothetical MSZ Mw 9.0 earthquake and tsunami, together with the Mw 9.1 Sumatra-Andaman earthquake and tsunami, show that the tsunami heights generated in Mumbai by an MSZ tsunami would be significantly larger than those generated by the 2004 Sumatra-Andaman tsunami. This result indicates that future tsunami hazard mitigation for Mumbai needs to be based on a potential large MSZ earthquake rather than an SASZ earthquake.
| Original language | English |
|---|---|
| Pages (from-to) | 1952-1964 |
| Number of pages | 13 |
| Journal | Geophysical Journal International |
| Volume | 222 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2 Jun 2020 |
Bibliographical note
Funding Information:The tide gauge data used in this research were provided by the Survey of India, Delhi (India), and the National Institute of Oceanography, Goa (India). We used the GMT software by Wessel & Smith (1998) for drafting the figures. MH is grateful to Jaishri Sanwal (Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India), Kusala Rajendran (Indian Institute of Science, Bangalore, India) and the staff at the Navi Mumbai Municipal Corporation (NMMC). A special acknowledgement to Vrindha Nath (NMMC), and to the Disaster Management Unit of Mumbai for helping with the field survey in the Mumbai region and for the fruitful discussions. The authors gratefully acknowledge Fred Stephenson (Institute of Ocean Sciences, Sidney, BC, Canada) for valuable comments and suggestions. The manuscript benefitted from constructive review comments from Prof Gabi Laske (the Editor) and two anonymous reviewers for which we are sincerely thankful. MH is grateful to Prof Serge Guillas (University College London, UK) for valuable discussions and encouragements. This research was funded by the Natural Environment Research Council (NERC) of the United Kingdom; contract number NE/P016367/1. MH was also funded by the Royal Society, the United Kingdom (grant number CHL/R1/180173). CPR acknowledges funding from the Board of Research in Nuclear Sciences, Department of Atomic Energy, Government of India. For AR, this work was partially supported by the Russian State Assignment of IORAS number 0149-2019-0005. The authors declare that they have no competing interests regarding the work presented in this paper.
Publisher Copyright:
© 2020 The Author(s) 2020. Published by Oxford University Press on behalf of The Royal Astronomical Society.
Funding
The tide gauge data used in this research were provided by the Survey of India, Delhi (India), and the National Institute of Oceanography, Goa (India). We used the GMT software by Wessel & Smith (1998) for drafting the figures. MH is grateful to Jaishri Sanwal (Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India), Kusala Rajendran (Indian Institute of Science, Bangalore, India) and the staff at the Navi Mumbai Municipal Corporation (NMMC). A special acknowledgement to Vrindha Nath (NMMC), and to the Disaster Management Unit of Mumbai for helping with the field survey in the Mumbai region and for the fruitful discussions. The authors gratefully acknowledge Fred Stephenson (Institute of Ocean Sciences, Sidney, BC, Canada) for valuable comments and suggestions. The manuscript benefitted from constructive review comments from Prof Gabi Laske (the Editor) and two anonymous reviewers for which we are sincerely thankful. MH is grateful to Prof Serge Guillas (University College London, UK) for valuable discussions and encouragements. This research was funded by the Natural Environment Research Council (NERC) of the United Kingdom; contract number NE/P016367/1. MH was also funded by the Royal Society, the United Kingdom (grant number CHL/R1/180173). CPR acknowledges funding from the Board of Research in Nuclear Sciences, Department of Atomic Energy, Government of India. For AR, this work was partially supported by the Russian State Assignment of IORAS number 0149-2019-0005. The authors declare that they have no competing interests regarding the work presented in this paper.
Keywords
- Earthquake hazards
- Earthquake source observations
- Indian Ocean
- Numerical modelling
- Subduction zone processes
- Tsunamis
ASJC Scopus subject areas
- Geophysics
- Geochemistry and Petrology