DOI: 10.1016/j.epsl.2017.11.040
Scopus记录号: 2-s2.0-85035333662
论文题名: Control on off-rift magmatism: A case study of the Baikal Rift Zone
作者: Yang H. ; Chemia Z. ; Artemieva I.M. ; Thybo H.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 482 起始页码: 501
结束页码: 509
语种: 英语
英文关键词: craton
; layered rheology
; lithosphere heterogeneity
; lower crust shearing
; pre-existing weak zone
; rift graben
Scopus关键词: Location
; Structural geology
; craton
; Geophysical evidence
; lithosphere heterogeneity
; Lithospheric mantle
; Lower crust
; Regional distribution
; rift graben
; Seismic observation
; Tectonics
; craton
; fault zone
; graben
; heterogeneity
; lithospheric structure
; lower crust
; magmatism
; rheology
; shear zone
; Baikal Rift Zone
; Russian Federation
英文摘要: The Baikal Rift Zone (BRZ) is an active intracontinental rift zone with almost no rift-related magmatism along the rift axis. Most magmatism is observed outside the rift center, and e.g. the major Vitim volcanic field is displaced more than 200 km from the rift center. The reasons for this regional distribution of the magmatism are enigmatic, in particular regarding the off-rift magmatism. We present results of numerical modeling of rift structures similar to BRZ that develop in the transition between craton and orogenic belt. Geophysical evidence suggests that pre-existing weak zones control the location of the BRZ. The models therefore include a pre-set fault (weak zone) within the transition zone between the craton and the orogenic belt as an initial condition in the model. If the pre-existing fault is close to the craton, partial melting in the mantle, due to sub-crustal extension, is offset from the surface rift graben by over 200 km. A horizontal shear zone in the lower crust transfers the extension from the shallow crust to the lithospheric mantle far from the rift graben. A pre-set fault close to the orogenic belt zone is required to explain magmatism close to the rift center in the southernmost BRZ. We conclude that the location of the pre-existing fault zone relative to a change in lithosphere thickness may shift the magmatism away from the surface expression of the rift graben and may explain the location of the off-rift magmatism, e.g. the basaltic Vitim plateau. The predicted geometry of the sedimentary graben along the rift strike is consistent with seismic observations in the northern and central BRZ. © 2017 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/110114
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: Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 101350, Denmark; School of Earth Science, University of Melbourne, Parkville, Victoria 3010, Australia; Eurasia Institute of Earth Science, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey; Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Blindern, Oslo, 0316, Norway
Recommended Citation:
Yang H.,Chemia Z.,Artemieva I.M.,et al. Control on off-rift magmatism: A case study of the Baikal Rift Zone[J]. Earth and Planetary Science Letters,2018-01-01,482