Molybdenum isotope composition of the upper mantle and its origin: insight from mid-ocean ridge basalt

• Published in: Journal of oceanology and limnology Vol. 42; no. 3; pp. 705 - 708
• Main Author: Chen, Shuo
• Format: Journal Article
• Language: English
• Published: Heidelberg Science Press 01.05.2024; Springer Nature B.V; Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China
• Subjects: Basalt; Earth and Environmental Science; Earth mantle; Earth Sciences; Heterogeneity; High temperature; Investigations; Isotope composition; Isotopes; Limnology; Mid-ocean ridges; Molybdenum; Molybdenum isotopes; Oceanic crust; Oceanography; Research Highlights; Subduction; Tracers; Upper mantle; Variation; mantle; crustal recycling; molybdenum (Mo) isotope; mid-ocean ridge basalt (MORB); mid-ocean ridge basalt(MORB); molybdenum(Mo)isotope
• ISSN: 2096-5508; 2523-3521
• DOI: 10.1007/s00343-024-3250-6

The molybdenum (Mo) isotope system is pivotal in reconstructing marine redox changes throughout Earth’s history and has emerged as a promising tracer for igneous and metamorphic processes. Understanding its composition and variation across major geochemical reservoirs is essential for its application in investigating high-temperature processes. However, there is debate regarding the δ 98/95 Mo value of the Earth’s mantle, with estimates ranging from sub-chondritic to super-chondritic values. Recent analyses of global mid-ocean ridge basalt (MORB) glasses revealed significant δ 98/95 Mo variations attributed to mantle heterogeneity, proposing a two-component mixing model to explain the observed variation. Complementary studies confirmed the sub-chondritic δ 98/95 Mo of the depleted upper mantle, suggesting remixing of subduction-modified oceanic crust as a plausible mechanism. These findings underscore the role of Mo isotopes as effective tracers for understanding dynamic processes associated with mantle-crustal recycling.