DOI: 10.1016/j.earscirev.2020.103170
论文题名: Widening of the Andes: An interplay between subduction dynamics and crustal wedge tectonics
作者: Martinod J. ; Gérault M. ; Husson L. ; Regard V.
刊名: Earth Science Reviews
ISSN: 00128252
出版年: 2020
卷: 204 语种: 英语
中文关键词: Andes
; Crustal wedge
; Flat-slab subduction
; Tectonics
英文关键词: continental lithosphere
; crustal structure
; plate tectonics
; slab
; subduction
; Andes
; Cordillera Oriental [Andes]
英文摘要: Shortening of the continental lithosphere is generally accommodated by the growth of crustal wedges building above megathrusts in the mantle lithosphere. We show that the locus of shortening in the western margin of South America has largely been controlled by the geometry of the slab. Numerical models confirm that horizontal subduction favors compression far from the trench, above the asthenospheric wedge and steeply dipping segment of the subducting slab. As a result, a second crustal wedge grows in the hinterland of the continent, and widens the Andes. In the Bolivian orocline, this wedge corresponds to the Eastern Cordillera, whose growth was triggered by a major episode of horizontal subduction. When the slab returned to a steeper dip angle, shortening and uplift pursued, facilitated by the structural and thermo-chemical alteration of the continental lithosphere. We review the successive episodes of horizontal subduction that have occurred beneath South America at different latitudes and show that they explain the diachronic widening of the Andes. We infer that the present-day segmented physiography of the Andes results from the latitudinally variable, transient interplay between slab dynamics and upper plate tectonics over the Cenozoic. We emphasize that slab flattening, or absence thereof, is a major driving mechanism that sets the width of the Andes, at any latitude. © 2020 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/166178
Appears in Collections: 气候变化与战略
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作者单位: Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, Grenoble, 38000, France; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; GET, Université de Toulouse, CNRS, UPS(OMP), IRD, CNES, 14 av. E. Belin, Toulouse, 31400, France
Recommended Citation:
Martinod J.,Gérault M.,Husson L.,et al. Widening of the Andes: An interplay between subduction dynamics and crustal wedge tectonics[J]. Earth Science Reviews,2020-01-01,204