and Western Australia (3.46 Ga (PDF). The Re-Os isochron is defined by the following equation: left(frac 187mathrm Os 188mathrm Os right mathrm present left(frac 187mathrm Os 188mathrm Os right mathrm initial left(frac 187mathrm Re 188mathrm Os right)cdot (elambda t-1 where: t is the age of the sample, is the decay constant. Earth and Planetary Science Letters. Bosch,.; Faestermann,.; Friese,.; Heine,.; Kienle,.; Wefers,.; Zeitelhack,.; Beckert,.;. 2, both rhenium and osmium are strongly siderophilic (iron loving while Re is also chalcophilic (sulfur loving) making it useful in dating sulfide ores such as gold and Cu-Ni deposits. For example, the boundaries of many Phanerozoic systems, epochs, and stages are marked by the deposition of black shale units, several of which are coincident with mass extinction events. In this regard, the ReOs system to study the geochemical evolution of mantle rocks and in defining the chronology of mantle differentiation is extremely helpful.
Rheniumosmium dating - Wikipedia Introduction to Re-Os - earthtime Dissecting the Re-Os molybdenite geochronometer Scientific Reports
Org Reference Database (ERR) - Shirey Walker 1998". Peridotite xenoliths which are thought to sample the upper mantle sometimes contain supra-chondritic Os-isotopic ratios. Analytical and instrument developments over the past 25 years have improved the reliability and accuracy of the method such that precision now routinely approaches 1 uncertainty. The stable and relatively abundant osmium isotope 188Os is used to normalize the radiogenic isotope in the isochron. Instead, determining model ages can be done in two ways: "Re depletion" model ages or the "melting age" model.