Revisiting Slip Deficit Rates and Its Insights Into Large and Slow Earthquakes at the Nankai Subduction Zone,Journal of Geophysical Research: Solid Earth

当前位置： X-MOL 学术 › J. Geophys. Res. Solid Earth › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Revisiting Slip Deficit Rates and Its Insights Into Large and Slow Earthquakes at the Nankai Subduction Zone
Journal of Geophysical Research: Solid Earth ( IF 3.9 ) Pub Date : 2024-12-20 , DOI: 10.1029/2023jb027942
Raymundo Plata-Martinez, Takeshi Iinuma, Fumiaki Tomita, Yasuyuki Nakamura, Takuya Nishimura, Takane Hori

The Nankai subduction zone presents significant seismic and tsunami risks, given its historical earthquakes exceeding magnitude 8 and the expectations of similar future events. Slow earthquakes, common at the shallow and deep plate interface, result from different frictional properties linked to interplate slip deficit accumulation. This study estimates slip deficit rates at the Nankai subduction zone using land and ocean-bottom geodetic data. Previous estimates encountered limitations, often smoothing slip deficits, omitting observational error differences between ocean-floor and land data, and relying on homogeneous structure models. To address these issues, we employ a novel trans-dimensional reversible jump Markov Chain Monte Carlo algorithm. This approach dynamically adjusts slip parameters, accommodating data resolution and producing a flexible slip distribution without predetermined spatial constraints. Additionally, it automatically weights data for observational errors and integrates elastic Green functions from a 3D structure of the Nankai region. Our results provide a finer, heterogeneous slip distribution, improving estimates in inland regions. However, limitations remain offshore in areas with sparse data. We revised the spatial distribution of Nankai slow earthquakes and confirmed a good agreement with intermediate slip deficit rates, identifying coupled and uncoupled regions. High slip deficit rates align with rupture areas of historic large earthquakes. Slow earthquakes occur at frictionally weak plate interfaces, and shallow slow earthquakes may result from subducting relief heterogeneities with important pore fluid pressure effects. We introduce an updated distribution of slip deficit rates for the Nankai subduction zone, considering observed slip deficit rates and the fast and slow earthquake occurrence.

更新日期：2024-12-20

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文