DOI: 10.1016/j.tecto.2021.228862
论文题名: Strike-slip seismicity at the Andaman-Sumatra Subduction Zone: Role of the fracture zones and age of the subducting lithosphere
作者: Jacob J. ; Dyment J. ; Ghosal D. ; Dewangan P.
刊名: Tectonophysics
ISSN: 00401951
出版年: 2021
卷: 811 语种: 英语
中文关键词: Andaman-Sumatra Subduction Zone
; Fracture zones
; Lithospheric age
; Strike-slip earthquakes
; Subductability
英文关键词: Fracture
; Focal mechanism
; Lithospheric age
; Lithospheric thickness
; Physical and mechanical properties
; Seismic records
; Strike-slip earthquakes
; Subducting plate
; Subduction zones
; Earthquakes
; age
; bulk density
; earthquake magnitude
; fracture zone
; seismic data
; seismicity
; strike-slip fault
; subduction zone
; Andaman Fault Zone
; Greater Sunda Islands
; Indian Ocean
; Sumatra
; Sunda Isles
英文摘要: A better comprehension of the shallow strike-slip seismicity along the Sunda Trench is achieved by superimposing the Wharton basin fracture zones, magnetic isochrones, and focal mechanisms to the geometry of the subducting plate. The shallow strike-slip seismicity is generally associated with the north-south trending fracture zones of the basins, which segment the subducting lithosphere into eight main compartments named A-H. Strike-slip earthquakes with magnitudes higher than 4.5 Mw in the time period of 2004–2019 are examined with respect to the thickness and density of the subducting lithosphere, estimated from the lithospheric age. Bulk density ranges from ~3258 to ~3272 and lithospheric thickness from ~74 to ~112 km between the younger fossil spreading axis and the older Compartment H, respectively. ‘Subductability’, a parameter calculated from lithospheric thickness and bulk density, is coined to represent the easiness of subduction and varies for each spreading compartment depending on the lithospheric age. We propose the correlation between the shallow strike-slip seismicity and the contrasts of lithospheric thickness, density and subductability. Considering the available seismic records from the past four decades, a prominent cluster of strike-slip earthquakes is observed along Fracture Zone B-C, which displays a strong subductability contrast, whereas other fracture zones displaying only minor seismicity correspond to low subductability contrasts. Despite a high subductability contrast, slab tearing on the subducting Investigator Fracture Zone between Compartments G and H prevents the generation of strike-slip earthquakes. This result emphasizes the importance of physical and mechanical properties of the subducting lithosphere in localizing the seismicity at subduction zones. © 2021 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/170826
Appears in Collections: 气候变化与战略
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作者单位: CSIR-National Institute of Oceanography, Dona Paula, Goa 403004, India; Université de Paris, Institut de physique du globe de Paris et CNRS, Paris, France; Indian Institute of Technology Kanpur, Kanpur, U.P. 208016, India
Recommended Citation:
Jacob J.,Dyment J.,Ghosal D.,et al. Strike-slip seismicity at the Andaman-Sumatra Subduction Zone: Role of the fracture zones and age of the subducting lithosphere[J]. Tectonophysics,2021-01-01,811