Formation
There are two strewnfield formation mechanisms:
- Mid-air fragmentation: when a large meteoroid enters the atmosphere it often fragments into many pieces before touching the ground due to thermal shock. This mid-air explosion causes the dispersion of the material over a large oval-shaped area. The orientation of this oval is determined by the flight path of the meteoroid. When multiple-explosions occur, the material can be found in several overlapping ovals.
- Impact fragmentation: when there is almost no mid-air fragmentation the fragmentation can occur upon impact. In this case the strewnfield shape can be different, usually circular. (e.g. Canyon Diablo at Meteor Crater; Australasian strewnfield)
Read more about this topic: Strewn Field
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