Glacier movement and ice sheet evolution

Cosmogenic nuclides can be used in two ways to estimate rates of tectonic uplift. For samples which were exposed long enough, such as those in the Antarctic Dry Valleys (see Glacier movement and ice sheet evolution section), the mere concentration of a cosmogenic nuclide provides constraints on the uplift rate because of the dependence of production rates on altitude. A maximum uplift rate is obtained under the assumption of steady uplift from sea level to the present elevation (cf. Bruno et al. 1997). This method has been applied to limit uplift in the Transantarctic Mountains to < 170 m/Ma (Brook et al. 1993 Ivy-Ochs et al. 1995 Bruno et al. 1997), as opposed to certain studies suggesting much higher rates up to 1000 m/Ma. 

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