New Insights into the Source of the Makran Tsunami of 27 November 1945 from Tsunami Waveforms and Coastal Deformation Data

NCUIR > College of Earth Sciences > Department of Earth Sciences > journal & Dissertation > Item 987654321/103868

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/103868

Title:	New Insights into the Source of the Makran Tsunami of 27 November 1945 from Tsunami Waveforms and Coastal Deformation Data
Authors:	佐竹健治;Heidarzadeh, Mohammad;Satake, Kenji
Contributors:	地球科學學院地球科學學系
Keywords:	Coasts;Data analysis;Deep water;Deformation;Earth and Environmental Science;Earth Sciences;Earthquakes;Gages;Gauges;Geophysics/Geodesy;Mumbai;Seismic activity;Sensitivity analysis;Slip;Spectral analysis;Tides;Tsunamis;Uplift;Water depth;Waveform analysis;Waveforms
Date:	2015-03-01
Issue Date:	2026-04-23 11:38:55 (UTC+8)
Publisher:	Birkhauser Verlag Basel;Basel: Springer Basel
Abstract:	摘要： We constrain the source of the 27 November 1945 tsunami in the Makran Subduction Zone (MSZ) using available tsunami waveforms recorded on tide gauges at Mumbai (India) and Karachi (Pakistan), and that inferred at Port Victoria (Seychelles), and coseismic deformation data along the Makran coast. Spectral analysis of the tsunami waveforms shows that the tsunami governing period was 40–50 min at Karachi whereas it was around 22 min at Mumbai. The inferred tsunami waveform at Port Victoria also indicated a period of around 21 min for the tsunami. Tsunami numerical simulations from the previously proposed source models failed in reproducing the observed tsunami waveforms and coseismic deformation data. Sensitivity analysis showed that the source fault needs to be extended offshore into deep water in order to reproduce the first 22-min signal at Mumbai. Based on the inversion of the observed tsunami waveforms, we propose a four-segment fault with varying slip amounts as the final source. This source includes a slip of 4.3 m onshore near Ormara (Pakistan) and a slip of 10 m offshore at water depth of around 3,000 m. The total fault length is 220 km, and the average slip is 6.1 m. This source, first, reproduces fairly well the observed tide gauge records at Mumbai and Karachi, second, produces ~1 m of uplift at Ormara and ~1 m of subsidence at Pasni, and third, gives a moment magnitude of 8.3 for the earthquake, which is in the acceptable range of seismic data. The computed 1 m uplift at Ormara is in the uplift range of 1–3 m reported in the literature. As the tide gauge stations were located in the far field, our proposed source explains mainly the tectonic source of the tsunami. 其他題名： Pure Appl. Geophys 出版者： Basel: Springer Basel 出版日期： 2015-03 出處： Pure and applied geophysics, 2015-03, Vol.172 (3-4), p.621-640 資源來源： Agricultural & Environmental Science Collection 版權： Springer Basel 2014 版權： Springer Basel 2015 識別號： ISSN: 0033-4553 識別號： EISSN: 1420-9136 識別號： DOI: 10.1007/s00024-014-0948-y
Appears in Collections:	[Department of Earth Sciences ] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	16	View/Open

社群 sharing

Loading...