气候变化领域集成服务门户(CCPortal): Lithospheric Control of Melt Generation Beneath the Rungwe Volcanic Province, East Africa: Implications for a Plume Source

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DOI	10.1029/2020JB020728
	Lithospheric Control of Melt Generation Beneath the Rungwe Volcanic Province, East Africa: Implications for a Plume Source
	Njinju E.A.; Stamps D.S.; Neumiller K.; Gallager J.
发表日期	2021
ISSN	21699313
卷号	126 期号:5
英文摘要	The Rungwe Volcanic Province (RVP) is a volcanic center in an anomalous region of magma-assisted rifting positioned within the magma-poor Western Branch of the East African Rift (EAR). The source of sublithospheric melt for the RVP is enigmatic, particularly since the volcanism is highly localized, unlike the Eastern Branch of the EAR. Some studies suggest the source of sublithospheric melt beneath the RVP arises from thermal perturbations in the upper mantle associated with an offshoot of the African superplume flowing from the SW, while others propose a similar mechanism, but from the Kenyan plume diverted around the Tanzania Craton from the NE. Another possibility is decompression melting from upwelling sublithospheric mantle due to lithospheric modulated convection (LMC) where the lithosphere is thin. The authors test the hypothesis that sublithospheric melt feeding the RVP can be generated from LMC. We develop a 3D thermomechanical model of LMC beneath the RVP and the Malawi Rift and constrain parameters for sublithospheric melt generation due to LMC. We assume a rigid lithosphere and use non-Newtonian, temperature-, pressure-, and porosity-dependent creep laws of anhydrous peridotite for the sublithospheric mantle. We find a pattern of upwelling from LMC beneath the RVP. The upwelling generates melt only for elevated mantle potential temperatures (Tp), which suggests a heat source possibly from plume material. At elevated Tp, LMC associated decompression melts occurs at a maximum depth of ∼150 km beneath the RVP. We suggest upwelling due to LMC entrains plume materials resulting in melt generation beneath the RVP. © 2021. The Authors.
英文关键词	East African Rift; lithospheric modulated convection; Malawi Rift Zone; melt generation; plume source; Rungwe Volcanic Province
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187137
作者单位	Department of Geosciences, Virginia Tech, Blacksburg, VA, United States; OPeNDAP, Narragansett, RI, United States
推荐引用方式 GB/T 7714	Njinju E.A.,Stamps D.S.,Neumiller K.,et al. Lithospheric Control of Melt Generation Beneath the Rungwe Volcanic Province, East Africa: Implications for a Plume Source[J],2021,126(5).
APA	Njinju E.A.,Stamps D.S.,Neumiller K.,&Gallager J..(2021).Lithospheric Control of Melt Generation Beneath the Rungwe Volcanic Province, East Africa: Implications for a Plume Source.Journal of Geophysical Research: Solid Earth,126(5).
MLA	Njinju E.A.,et al."Lithospheric Control of Melt Generation Beneath the Rungwe Volcanic Province, East Africa: Implications for a Plume Source".Journal of Geophysical Research: Solid Earth 126.5(2021).