Precipitation trapped in datable rock-forming minerals: estimating Antarctic palaeoelevations - a discussion

Abstract

Meteoric water that interacted with minerals during retrogressive metamorphism and hydrothermalism in the late-stage of mountain building processes contains hydrogen and oxygen isotopes that are potential proxies for palaeoelevation reconstruction in Antarctica. The effects of temperature on meteoric isotopic signatures, meteoric crustal infiltration processes, and the mechanisms of capture and preservation of meteoric δD and δ 18 O values in rock-forming minerals are discussed. Special emphasis is given to Antarctica's geographical high-latitude position and climatic fluctuations over time and to the highmountain ranges of continental Antarctica, which were tectonically active regions in the past. In this context, a new compilation of recent Antarctic snow and ice δD and δ 18 O data is presented, by which we demonstrate that net elevations versus isotopic depletions are positively correlated for continental Antarctica -a prime requisite when estimating palaeoelevations.