Cosmogenic dating labs
High-energy cosmic rays shower the Earth's surface, penetrating meters into rock and producing long-lived radionuclides such as Cl-36, Al-26 and Be-10.Production rates are almost unimaginably small - a few atoms per gram of rock per year - yet we can detect and count these "cosmogenic isotopes" using accelerator mass spectrometry, down to levels of a few thousand atoms per gram (parts per billion of parts per billion! The build-up of cosmogenic isotopes through time provides us with a way to measure exposure ages for rock surfaces such as fault scarps, lava flows and glacial pavements.Absolute sating of glacial moraines and river terraces, for example provide vital constraints on paleo-climate impacts on the landscape.
We currently process ~100 samples per year for a number of cosmogenic nuclides, such as beryllium-10, aluminium-26, and chlorine-36, from a wide variety of lithologies, but have the capacity for over 200 samples per year.
The applications of cosmogenic nuclide methods span the Earth Sciences.
can be used to determine how long that material has been exposed at Earth’s surface.
This allows us to calculate exposure ages and erosion rates at Earth’s surface.
The Cosmogenic Nuclide Laboratory at SGEES was purpose built in 2014 for the preparation of cosmogenic nuclide samples from all branches of the Earth sciences.
The facilities include 2 HF rated extraction hoods and one laminar flow hood, Parr pressure dissolution oven, as well as analytical balances and centrifuge.