Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected

Abstract The moment‐duration (M0‐T) scaling law reveals fundamental earthquake physics across various sizes and tectonic settings. However, the validity of the cubic relation (M0 ∝ T3) inferred for large (Mw ≥ 7) megathrust events has been recently questioned due to the scarcity of observations and...

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Main Authors: Yumin Cui, Shaoyang Li, Ling Chen, Yosuke Aoki
Format: Article
Language:English
Published: Wiley 2025-04-01
Series:Geophysical Research Letters
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Online Access:https://doi.org/10.1029/2024GL112985
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author Yumin Cui
Shaoyang Li
Ling Chen
Yosuke Aoki
author_facet Yumin Cui
Shaoyang Li
Ling Chen
Yosuke Aoki
author_sort Yumin Cui
collection DOAJ
description Abstract The moment‐duration (M0‐T) scaling law reveals fundamental earthquake physics across various sizes and tectonic settings. However, the validity of the cubic relation (M0 ∝ T3) inferred for large (Mw ≥ 7) megathrust events has been recently questioned due to the scarcity of observations and similarities to slow earthquakes. Here, by compiling events over the past 500 years from global subduction zones, we double the number of earthquakes studied (>260) compared to previous studies. A possible scale change is observed, at moment‐magnitude and duration of ∼7.6 and ∼38.1 s, respectively. The new catalog reveals an accelerated decrease of the scaling exponent as a function of magnitude from 2.5 (Mw ≥ 7) to below 1 (Mw > 8.7), indicating increasingly longer durations than expected for larger events. The rapid increase in duration with earthquake size is interpreted as the interplay of seismogenic bounds, trench‐breaching, and subevents, which delays lateral rupture propagation. Our study aids in understanding slow and fast earthquakes.
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institution Kabale University
issn 0094-8276
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language English
publishDate 2025-04-01
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series Geophysical Research Letters
spelling doaj-art-4b32ebd88b114f48a671328c3a6abbdb2025-08-20T03:39:04ZengWileyGeophysical Research Letters0094-82761944-80072025-04-01528n/an/a10.1029/2024GL112985Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than ExpectedYumin Cui0Shaoyang Li1Ling Chen2Yosuke Aoki3State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing ChinaState Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing ChinaState Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing ChinaEarthquake Research Institute The University of Tokyo Tokyo JapanAbstract The moment‐duration (M0‐T) scaling law reveals fundamental earthquake physics across various sizes and tectonic settings. However, the validity of the cubic relation (M0 ∝ T3) inferred for large (Mw ≥ 7) megathrust events has been recently questioned due to the scarcity of observations and similarities to slow earthquakes. Here, by compiling events over the past 500 years from global subduction zones, we double the number of earthquakes studied (>260) compared to previous studies. A possible scale change is observed, at moment‐magnitude and duration of ∼7.6 and ∼38.1 s, respectively. The new catalog reveals an accelerated decrease of the scaling exponent as a function of magnitude from 2.5 (Mw ≥ 7) to below 1 (Mw > 8.7), indicating increasingly longer durations than expected for larger events. The rapid increase in duration with earthquake size is interpreted as the interplay of seismogenic bounds, trench‐breaching, and subevents, which delays lateral rupture propagation. Our study aids in understanding slow and fast earthquakes.https://doi.org/10.1029/2024GL112985megathrust earthquakescaling lawsslow and fast earthquakes
spellingShingle Yumin Cui
Shaoyang Li
Ling Chen
Yosuke Aoki
Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
Geophysical Research Letters
megathrust earthquake
scaling laws
slow and fast earthquakes
title Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
title_full Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
title_fullStr Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
title_full_unstemmed Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
title_short Large Megathrust Earthquakes Tend to Sustain an Increasingly Longer Duration Than Expected
title_sort large megathrust earthquakes tend to sustain an increasingly longer duration than expected
topic megathrust earthquake
scaling laws
slow and fast earthquakes
url https://doi.org/10.1029/2024GL112985
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AT shaoyangli largemegathrustearthquakestendtosustainanincreasinglylongerdurationthanexpected
AT lingchen largemegathrustearthquakestendtosustainanincreasinglylongerdurationthanexpected
AT yosukeaoki largemegathrustearthquakestendtosustainanincreasinglylongerdurationthanexpected