Ice field stranding zone
A stranding zone is a blue-ice area in Antarctica where flowing ice carries meteorites to the surface and concentrates them.
Antarctica's ice sheet slowly flows outwards from the centre of the continent. Meteorites that land on it are buried in snow and carried along inside the ice. Where the flow is blocked by mountains or buried ridges, the ice is pushed upwards. Strong, dry winds then wear away the surface ice faster than snow can build up, exposing the old blue ice beneath. Meteorites carried within the ice are brought to the surface and left lying on top.
These stranding zones, or blue-ice fields, can hold dozens or even hundreds of meteorites per square kilometre. The Allan Hills, Yamato Mountains and Grove Mountains are famous examples. Some meteorites found there landed more than a million years ago.
In 2022 researchers used satellite data and machine learning to map likely stranding zones, estimating that hundreds of thousands of meteorites may remain to be found. Some may be sinking into the ice as the climate warms, because dark stones absorb sunlight and melt their way down.
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