Accretion of the cratonic mantle lithosphere via massive regional relamination.

Continental, orogenic, and oceanic lithospheric mantle embeds sizeable parcels of exotic cratonic lithospheric mantle (CLM) derived from distant, unrelated sources. This hints that CLM recycling into the mantle and its eventual upwelling and relamination at the base of younger plates contribute to the complex structure of the growing lithosphere. Here, we use numerical modeling to investigate the fate and survival of recycled CLM in the ambient mantle and test the viability of CLM relamination under Hadean to present-day mantle temperature conditions and its role in early lithosphere evolution.

Isotopic Analysis by Laser Ablation Solution Sampling MC-ICP-MS─An Example of Boron.

Using boron as a test analyte, laser ablation (LA) solution sampling multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) is proposed and validated as a fast method for isotopic analysis in natural liquids and digested samples without any prior purification process. We demonstrated that the solution reference standard can be used as a bracketing standard for in situ δB analysis in solids. Based on a sensitivity enhancement of 8- to 9-fold, all testing solutions were diluted in a 5% (v/v) NH·HO instead of classical 2% (v/v) HNO.

Significant Zr isotope variations in single zircon grains recording magma evolution history.

Zircons widely occur in magmatic rocks and often display internal zonation finely recording the magmatic history. Here, we presented in situ high-precision (2SD <0.15‰ for δZr) and high-spatial-resolution (20 µm) stable Zr isotope compositions of magmatic zircons in a suite of calc-alkaline plutonic rocks from the juvenile part of the Gangdese arc, southern Tibet.

Determination of Cl, Br, and I in Geological Materials by Sector Field Inductively Coupled Plasma Mass Spectrometry.

In this study, a simple and effective method for the simultaneous analysis of Cl, Br, and I in geological materials based on NHHF digestion in open vessels (Savillex Teflon vials) is proposed. It is very interesting to note that Cl, Br, and I are not lost during NHHF digestion at temperatures of 200-240 °C for 0.5-12 h in open vessels.

Ratios of S, Se and Te in the silicate Earth require a volatile-rich late veneer.

The excess of highly siderophile (iron-loving) elements (HSEs) and the chondritic ratios of most HSEs in the bulk silicate Earth (BSE) may reflect the accretion of a chondritic 'late veneer' of about 0.5 per cent of Earth's mass after core formation. The amount of volatiles contained in the late veneer is a key constraint on the budget and the origin of the volatiles in Earth.