Dating Dry Valley Deltas Down Under

Michael Stone, PhD student at Louisiana State University, is interested in understanding how Lake Fryxell, and its surrounding ecosystem responded to climate fluctuations in the McMurdo Dry Valleys, Antarctica. By dating perched deltas, he’s reconstructing the history of lake level change, which in turn can tell us more about the timing of the retreat of the Ross Ice Sheet following the last glaciation. At DRILL, Michael is dating perched deltas using single grains of feldspar. The age distribution derived from multiple grains from each sample not only gives us an age estimate for the delta, but also tells us about the bleaching history of the grains, and therefore the delta surface conditions at the time of sediment deposition.