DOI: 10.1016/j.epsl.2021.116981
论文题名: Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge
作者: Sanfilippo A. ; Salters V.J.M. ; Sokolov S.Y. ; Peyve A.A. ; Stracke A.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2021
卷: 566 语种: 英语
中文关键词: depleted mantle
; Knipovich Ridge
; magma mixing
; Mid Ocean Ridge Basalts
; Nd-Hf isotopes
英文关键词: Basalt
; Binary alloys
; Hafnium
; Hafnium alloys
; Melting
; Mixing
; Neodymium alloys
; Recycling
; Refractory materials
; Submarine geology
; Depleted mantle
; Hf isotope
; Isotope ratio
; Knipovich Ridge
; Magma mixing
; Mid Atlantic Ridge
; Mid-ocean ridge basalt
; Nd-hf isotope
; Re-melting
; Upper mantle
; Isotopes
; asthenosphere
; hafnium
; isotopic ratio
; magma
; melting
; mid-ocean ridge basalt
; neodymium isotope
; upper mantle
; Arctic Ocean
; Atlantic Ocean
; Knipovich Ridge
; Mid-Atlantic Ridge
; Mohns Ridge
; Norwegian Sea
英文摘要: The upper mantle is a heterogeneous mixture of refractory and recycled crustal domains. The recycled portions, more fertile and thus preferentially melted, dominate the composition of the basalts erupted on the surface, whereas the imprint of melting of the refractory counterparts is more difficult to discern from the basalt chemistry. Contrasting radiogenic isotopic signatures of mid-ocean ridge basalts and oceanic mantle, however, show that Hf isotope ratios may provide hints for melting of refractory source materials despite ubiquitous magma mixing during ascent and stalling in the crust. This property may allow identifying contributions from depleted mantle materials unseen in other isotope systematics in basalts. Here, we show that basalts from Mohns and Knipovich ridges, two >500-km long oblique super-segments in the Arctic Atlantic, have distinctly high Hf isotope ratios, not mirrored by comparatively high Nd and low Sr and Pb isotope ratios. These compositions can be explained if a highly depleted asthenospheric mantle melts beneath this section of the Arctic Mid Atlantic Ridge. We argue that this depleted source consists of high proportions of ancient (>1 Ga), ultra-depleted mantle, previously drained of enriched components before being re-melted in its current location following a recent ridge-jump, allowing the identification of ultra-depleted mantle components in the arctic subridge mantle. © 2021 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165661
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Dipartimento di Scienze della Terra e dell'Ambiente, Università di Pavia, Pavia, Italy; Department of Earth, Ocean Atmospheric Science, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, United States; Geological Institute, Russian Academy of Science, Moscow, Russian Federation; Institut für Mineralogie, Westfälische Wilhelms-Universität, Münster, Germany
Recommended Citation:
Sanfilippo A.,Salters V.J.M.,Sokolov S.Y.,et al. Ancient refractory asthenosphere revealed by mantle re-melting at the Arctic Mid Atlantic Ridge[J]. Earth and Planetary Science Letters,2021-01-01,566