Australasian strewnfield

The Australasian strewnfield, covering at least one-tenth of the Earth's surface, is the largest and the youngest of the tektite strewnfields. The 800,000-year-old strewnfield includes most of Southeast Asia (Vietnam, Thailand, Southern China, Laos and Cambodia). The material from the impact stretches across the ocean to include the islands of the Philippines, Indonesia, Malaysia and Java and reaches far out into the Indian Ocean and south to the western side of Australia.

File:Australasian strewnfield.jpg

Australasian strewnfield.

The impact crater may have been between 32 and 114 kilometres in diameter (compare to the 180-km Chicxulub crater). Also, some recent estimates suggest that the strewn field may cover 30% of the Earth's surface.

Archeological artifacts found with these tektites suggests that a Homo Erectus population was living in the area during and after the impact. Stone tools have been found within the debris field along with a charcoal layer likely caused by fires from the impact. This impact area allowed this population easier access to stones useful for tool making, after the subsequent local deforestation. At Trinil, Java, blackened bone and charcoal deposits have been found among H. erectus fossils, dated from 500,000 to 830,000 BP indicating use of fire.

See also

• Australite

Bibliography

• Glass B.P. and Pizzuto J.E. (1994) "Geographic variation in Australasian microtektite concentrations: Implications concerning the location and size of the source crater," J of Geophysical Research, vol 99, no E9, 19075-19081, Sept 1994 (abstract only).
• Glass B.P. (1999) "Muong Nong-type Australasian tektites: implications regarding the parent material and source area," Ninth Annual V.B.m Goldschmidt Conference, Massachusetts, August 1999.
• Paine M. (2001) "Source of the Australasian Tektites?" Meteorite, Feb 2001.
• Hartung J. and Koberl C. (1994) "In search of the Australasian tektite source crater: the Tonle sap hypothesis", Meteoritics.
• Povenmire H., Liu W. and Xianlin I. (1999) "Australasian tektites found in Guangxi Province, China," 30th Annual Lunar and Planetary Science Conference, Houston, March 1999.
• Schnetzler C. C. and Mchone J.F. (1996) "Source of Australasian tektites: Investigating possible impact sites in Laos," Meteoritics and Planetary Science, Vol. 31, p. 73-76
• Schmidt G. and Wasson J. (July 1993) "Masses of the impactor, the Australasian tektites, and size estimates of the main source crater," Meteoritics, vol 28 no .3, 430.
• Schmidt G. and Wasson J. (1993) "Iridium in sediments containing large abundances of Australasian microtektites from DSDP hole 758B in the Eastern Indian ocean and from DSDP hole 769A in the Sulu Sea," Proceedings of 24th Lunar and Planetary Science conference