Meteorites that fell centuries or millennia ago today can be found in certain desert environments. These finds share some common characteristics and find circumstances worthwhile discussing.
SHIELDING FROM WEATHERING
The most common find situation in hot deserts occurs on erosion and deflation surfaces where the accumulated soil, that contains the meteorites, is constantly eroded by the ever blowing wind. Meteorites found in these places usually represent millennia old fall events that occurred under climate conditions often less arid than today.
These meteorites fell onto and were embedded in the soil at times when the respective soil surfaces used to be sedimentation or at least stagnant soil horizons, often shielded from wind and fluvial erosion by a protective cover of vegetation. Embedded in the soil they often withstood the destructive forces of weathering for thousands and sometimes ten thousands of years. After climate changes, which frequently occurred in geological times in the current African and Arabian deserts, deflation processes uncovered them and brought them to rest on today’s desert surface.