DOI: 10.1016/j.epsl.2018.06.046
Scopus记录号: 2-s2.0-85049846545
论文题名: Strain budget of the Ecuador–Colombia subduction zone: A stochastic view
作者: Gombert B. ; Duputel Z. ; Jolivet R. ; Simons M. ; Jiang J. ; Liang C. ; Fielding E.J. ; Rivera L.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 498 起始页码: 288
结束页码: 299
语种: 英语
英文关键词: bayesian inversion
; Ecuador–Colombia subduction zone
; geodetic coupling model
; kinematic source model
; strain budget
Scopus关键词: Budget control
; Geodesy
; Geodetic satellites
; Kinematics
; Stochastic models
; Stochastic systems
; Tectonics
; Bayesian inversion
; Colombia
; Coupling modeling
; Frictional properties
; Historical earthquakes
; Kinematic slip models
; Source modeling
; Strong heterogeneities
; Earthquakes
; Bayesian analysis
; coseismic process
; earthquake event
; earthquake magnitude
; earthquake rupture
; GPS
; inverse problem
; stochasticity
; subduction zone
; teleseismic wave
; Columbia [Missouri]
; Ecuador
; Missouri
; United States
英文摘要: The 2016 Pedernales earthquake (MW=7.8) ruptured a portion of the Colombia–Ecuador subduction interface where several large historical earthquakes have been documented since the great 1906 earthquake (M=8.6). Considering all significant ruptures that occurred in the region, it has been suggested that the cumulative moment generated co-seismically along this part of the subduction over the last century exceeds the moment deficit accumulated inter-seismically since 1906. Such an excess challenges simple models with earthquakes resetting the elastic strain accumulated inter-seismically in locked asperities. These inferences are however associated with large uncertainties that are generally unknown. The impact of spatial smoothing constraints on co-seismic and inter-seismic models also prevents any robust assessment of the strain budget. We propose a Bayesian kinematic slip model of the 2016 Pedernales earthquake using the most comprehensive dataset to date including InSAR and GPS offsets, tsunami waveforms, and kinematic records from high-rate GPS and strong-motions. In addition, we use inter-seismic geodetic velocities to produce a probabilistic inter-seismic coupling model of the subduction interface. Our stochastic co-seismic and inter-seismic solutions include the ensemble of all plausible models consistent with our prior information and that fit the observations within uncertainties. The analysis of these model ensembles indicates that an excess of co-seismic moment during the 1906–2016 period is likely in Central Ecuador only if we assume that 1942 and 2016 earthquakes are colocated. If this assumption is relaxed, we show that this conclusion no longer holds given uncertainties in co- and inter-seismic processes. The comparison of 1942 and 2016 teleseismic records reveals large uncertainties in the location of the 1942 event, hampering our ability to draw strong conclusions on the unbalanced moment budget in the region. Our results also show a heterogeneous coupling of the subduction interface that coincides with two slip asperities in our co-seismic model for the 2016 Pedernales earthquake and with the location of historical ruptures in 1958, 1979 and 1998. The spatial variability in coupling and complexity in earthquake history suggest strong heterogeneities in frictional properties of the subduction megathrust. © 2018 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109764
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Institut de Physique du Globe de Strasbourg, UMR7516, Université de Strasbourg, EOST/CNRS, France; Laboratoire de géologie, Département de Géosciences, École Normale Supérieure, PSL Research University, CNRS UMR 8538, Paris, France; Seismological Laboratory, Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States; Institute of Geophysics and Planetary Physics, University of California, La Jolla, San Diego, CA, United States; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
Recommended Citation:
Gombert B.,Duputel Z.,Jolivet R.,et al. Strain budget of the Ecuador–Colombia subduction zone: A stochastic view[J]. Earth and Planetary Science Letters,2018-01-01,498