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This long period of applicability is an added advantage of cosmogenic nuclide dating.

It is particularly useful in Antarctica[1], because of a number of factors[2]: Cosmogenic nuclide dating is effective over short to long timescales (1,000-10,000,000 years), depending on which isotope you are dating.

Different isotopes are used for different lengths of times.

The most direct method is to count annual layers in much the same way that tree-rings can be counted to determine the age of the tree.

However, the layers in ice cores are not generally visible in the ice.

Once exposed to the atmosphere, the boulder will begin to accumulate cosmogenic nuclides.

Assuming that the boulder remains in a stable position, and does not roll or move after deposition, this boulder will give an excellent As well as using cosmogenic nuclide dating to work out the past extent of ice sheets and the rate at which they shrank back, we can use it to work out ice-sheet thicknesses and rates of thinning[5, 6].Dating glacial landforms helps scientists understand past ice-sheet extent and rates of ice-sheet recession.The basic principle states that a rock on a moraine originated from underneath the glacier, where it was plucked and then transported subglacially.They only become apparent when the core is analysed for a chemical signal that varies with the seasons, which most signals do, to some extent.In fact the clearest dating is obtained when several seasonal signals are examined and compared.Many cores however come from regions where the yearly snowfall accumulation is too small for the annual layers to be distinguished, and other methods of dating must be used.