DOI: 10.1002/2014GL060255
论文题名: Effects of the postperovskite phase change on the observed geoid
作者: Shahraki M. ; Schmeling H. ; Kaban M.K. ; Petrunin A.G.
刊名: Geophysical Research Letters
ISSN: 0094-9090
EISSN: 1944-8821
出版年: 2015
卷: 42, 期: 1 起始页码: 44
结束页码: 52
语种: 英语
英文关键词: dynamic topography
; geoid
; phase transitions
; postperovskite
Scopus关键词: Boundary layers
; Phase transitions
; Seismology
; Dynamic topography
; geoid
; Mantle circulation model
; Post-perovskite
; Post-perovskite phase change
; Seismic velocities
; Thermal boundary layer
; Viscosity variations
; Viscosity
; geoid
; mantle
; perovskite
; phase equilibrium
; seismic velocity
; subduction zone
; Pacific Ocean
英文摘要: In the lowermost mantle, seismic velocity variations beneath Pacific margins have been related to the perovskite to postperovskite (pPv) phase transition. We investigate the influence of this phase transformation on the geoid using 3-D spherical mantle circulation models based on a seismic tomography model and strong lateral viscosity variations in the lower mantle. We demonstrate that the geoid anomalies are strongly affected by the presence of pPv because of phase-dependent viscosity changes relative to the surrounding mantle. Whereas geoid heights above subduction zones are increased for high-viscosity pPv, the presence of weak pPv reduces them, thereby improving the fit to the observed geoid. An investigation using two different tomography models, different pPv density contrasts, and the presence or absence of a global thermal boundary layer and of lateral viscosity variations in the lower mantle demonstrates the various effects of weak pPv on the geoid. Key Points Geoid anomalies are strongly affected by the presence of pPv While geoid increased for the high viscous pPv, the weak pPv reduces the geoid Robustness tests with different parameters were performed, and the result noted ©2014. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84921826156&doi=10.1002%2f2014GL060255&partnerID=40&md5=43639b82b67c04bf8ed43ba30c62a2b9
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/8706
Appears in Collections: 科学计划与规划 气候变化与战略
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作者单位: Institut für Geowissenschaften, Facheinheit Geophysik, Goethe Universität, Frankfurt am Main, Germany
Recommended Citation:
Shahraki M.,Schmeling H.,Kaban M.K.,et al. Effects of the postperovskite phase change on the observed geoid[J]. Geophysical Research Letters,2015-01-01,42(1).