A fundamental challenge in modern mantle geochemistry is to link geochemical data with geological and geophysical observations. Most of the early geochemical models involved a layered mantle and the concept of geochemical reservoirs. Indeed, the two layer mantle model has been implicit in almost all geochemical literature and the provenance of oceanic island basalt (OIB) and mid-ocean ridge bas...

Numerous research data have been obtained about the Sumdo Palaeo‐Tethys, but reports on occurrence of Permian Ocean islands are relatively scarce. Here, we present zircon U–Pb geochronology, geochemistry, and in situ Hf isotopic characteristics ocean island basalt (OIB)‐type gabbros from Ewulang Nianqing‐Sumdo, Tibet. The age OIB‐type is 263 Ma (the Middle Permian), representing formation gabbr...

The Earth’s mantle exhibits marked chemical heterogeneity. We provide an examination of thallium systematics in ocean island basalts (OIB): new high-precision trace element analyses, including Tl, and Tl isotopic compositions for 48 OIB spanning the entire range observed Sr-Nd-Hf-Pb isotope ratios. All investigated are characterised by ubiquitous depletion requiring sources to have concentratio...

Plio–Pleistocene (3.4–0.125 Ma) post-plateau magmatism in the Meseta del Lago Buenos Aires (MLBA; 46.7jS) in southern Patagonia is linked with the formation of asthenospheric slab windows due to ridge collision along the Andean margin f 6 Ma ago. MLBA post-plateau lavas are highly alkaline (43–49% SiO2; 5–8% Na2O+K2O), relatively primitive (6–10% MgO) mafic volcanics that have strong OIB-like g...

We investigated mantle noble gas abundance ratios using a global compilation of data from mid-ocean ridge basalts (MORB) and high 3He/4He ocean island (OIB), coupled with calculated abundances based on closed-system evolution models. Assuming that the sources MORB OIB are derived same early Earth parental material, variations in their useful to ascertain which source is more depleted or degasse...

It is well known that intraday returns tend to reverse the following period, conditional on excess buying pressure bid or ask side. This suggests liquidity providers “overreact” order imbalance (OIB) by initially altering quotes so much a negative autocorrelation seen in mid-price returns. We investigate under which circumstances this behavior most common. Specifically, it seems tick size augme...

The mantle beneath coastal SE China evolved from enriched to depleted between the Cretaceous and Neogene, although precise timing of this change remains unclear. Here, we focus on a newly discovered Eocene mafic volcanic neck that contains peridotite xenoliths in Fuding area Fujian Province, present new whole-rock Ar–Ar data which indicate flood basalts formed during (ages 38.5 ± 1.2 42.3 2 Ma)...

Abstract Most efforts to characterize the size and composition of mantle that complements continental crust have assumed mid‐ocean ridge basalt (MORB) source is incompatible‐element depleted residue extraction. The use Nd isotopes model this process led conclusion “depleted MORB reservoir” confined upper ∼30% mantle, leaving lower in a more “primitive” state. Here, we Nb/U Ta/U evaluate mass re...

Lithological heterogeneity is a widely accepted feature of the Earth’s mantle, with recycled crustal material accounting for significant part in ocean island basalt (OIB) geochemistry. Fe isotopes have been used to link geochemical OIB sources distinct mantle lithologies due their mineral-specific equilibrium fractionation effects, or composition, such as incorporation kinetically-fractionated ...