The Re‐Os Isotopic System: A Review of Analytical Techniques

Abstract

Over the past twenty years, successive technological advances have transformed the Re‐Os isotopic system into one of the most powerful tools in isotope geochemistry. We present here a brief historical review of these advances and then describe and compare the methods most commonly used today. Our goal is to facilitate the choice of the analytical method best adapted to each specific scientific problem and sample type.

TIMS versus multicollector-ICP-MS: coexistence or struggle for survival?

“…As an example, the high ionization potential of hafnium makes MC-ICP-MS more suitable for this element [12]. In contrast, osmium isotope ratio measurements are technically less demanding to perform by TIMS at higher sensitivity and precision by bleeding oxygen into the ion source [15,16]. Without question, MC-ICP-MS has opened new doors in science, in particular for studying small natural isotope fractionation effects for the heavier elements such as iron, which are difficult to measure using TIMS [17].…”

The effect of oxygen fugacity on the partitioning of Re between crystals and silicate melt during mantle melting

“…The contrasting geochemical behaviour of Re and Os, which are found empirically to be mildly incompatible and compatible, respectively, during partial melting of the mantle, makes this system unique among the commonly used isotopic chronometers because in all the other systems (i.e., K-Ar, Rb-Sr, Sm-Nd, Lu-Hf, and U-Th-Pb-He) both parents and daughters are highly incompatible trace elements. Advances in analytical techniques now enable the very low Re and Os concentrations and the Os isotopic composition of terrestrial rocks to be analysed with precision (Reisberg and Meisel, 2002). However, our basic understanding of the high-temperature geochemical properties of Re and Os has not kept pace with these analytical advances, and the interpretation of Re-Os isotopic systematics in mantle and mantle-derived rocks is currently hindered by our lack of knowledge of how Re and Os behave during mantle melting and magma genesis.…”

Disequilibrium-induced initial Os isotopic heterogeneity in gram aliquots of single basaltic rock powders: Implications for dating and source tracing

“…Given their chalcophile and siderophile geochemical behavior, both Re and Os have a strong affinity to trace phases (e.g., sulfides and alloys) and, thus, their budgets in these rocks are controlled mainly by these trace phases. The contribution of unequal distribution of these discrete trace phases on poor reproducibility of both Re and Os concentrations in applications of the isotopic system has been well documented in the past two decades, known as the nugget effect (e.g., Reisberg and Meisel, 2002;Moser, 2001, 2004a;Meisel and Moser, 2004b). However, its effect on the scale of initial Os isotopic heterogeneity is unclear.…”