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Proterozoic sedimentary successions often record enormous portions of geological time, yet many of them lack volcanic horizons and are bereft of fossils suitable for relative age dating.
Suitable lithologies for Re-Os geochronology include black shales and organic-rich carbonates.
In addition to geochronology data, the Re-Os geochronometer provides the Os isotope composition (Os = 0.12) derived from cosmic dust and hydrothermal alteration of oceanic crust.
The Rhenium-Osmium (Re-Os) geochronometer is a novel tool for dating ancient sedimentary successions.
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.