Mid-air fragmentation. When a large meteor enters the atmosphere it often fragments into many pieces. This showers the material over a large oval-shaped area. The shape of this oval is caused by the flight path of the meteor. When multiple-explosions occur, the material may be found in several overlapping ovals.
Impact fragmentation: the fragmentation can occur on impact. In this case the strewnfield shape may be different, usually circular.
The Australasian strewnfield is the youngest and largest of the tektite strewnfields. Recent estimates suggest it may cover 10%-30% of the Earth's surface.[4]
↑French, Bevan M 1998. Traces of Catastrophe: a handbook of shock-metamorphic effects in terrestrial meteorite impact structures. LPI Contribution No. 954. Houston: Lunar and Planetary Institute. [1]
↑Povenmire H; Liu W. & Xianlin I. 1999. Australasian tektites found in Guangxi Province, China. 30th Annual Lunar and Planetary Science Conference, Houston.