Antarctica is the world’s premier meteorite hunting-ground for two reasons. Although meteorites fall in a random fashion all over the globe, the likelihood of finding a meteorite is enhanced if the background material is plain and the accumulation rate of indigenous sediment is low. Consequently the East Antarctic icesheet, a desert of ice, provides an ideal background for meteorite recovery- go to the right place, and any rock you find must have fallen from the sky. This allows the recovery of meteorites without bias toward types that look most different from earth rocks (a problem on the inhabited continents) and without bias toward larger sizes.
But another factor may be equally important. As the East Antarctic icesheet flows toward the margins of the continent, its progress is occassionally blocked by mountains or obstructions below the surface of the ice. In these areas, old deep ice is pushed to the surface and can become stagnant, with very little outflow and consistent, slow inflow. When such places are exposed to strong katabatic winds, massive deflation results, removing large volumes of ice and preventing accumulation of snow while leaving a lag deposit of meteorites on the surface. These areas exhibit a variable balance between infall, iceflow and deflation, all of which are intimately tied to environmental change during recent Antarctic history. Over significant stretches of time (tens of thousands of years) phenomenal concentrations of meteorites can develop, as high as 1 per square meter in some locations. Terrestrial exposure ages of meteorites suggest that some stranding surfaces may have been active for hundreds of thousands, or even millions of years.
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