Impact of Supraglacial Lakes on Ice-Shelf Stability

We study ice-shelf response to meltwater load movement in the area of the McMurdo Ice Shelf adjacent to McMurdo Station and the Pegasus Ice Runway. As meltwater accumulated in surface lakes on the floating ice shelf, the ice shelf must flex in accord with hydrostatic equilibrium (floatation). This flexure may be a significant cause of ice-shelf fracture that is important in ice-shelf instability. The purpose of our use of seismological equipment is to examine the field area for seismic signals that may merit more intensive study in a future field project. In essence, our work is a "pilot study" of signal presence and strength.