Abstract:

Thermoluminescence studies of meteorites suggest that the level of natural TL in meteorites is determined by competition between build up,due to exposure to cosmic radiation,and thermal decay.The cosmic dose rate (determined primarily by shielding) and albedo directly affect the level of natural TL in meteorites.Relative to non Antarctic meteorites,Antarctic meteorites have lower level of natural TL due to their large terrestrial ages.Some meteorites ( ～15%) have especially low natural TL,suggesting that they have recently been reheated.These may have come to earth on orbits with particularly small perihelion (<0.8 AU).The TL sensitivity of ordinary chondrites reflects the abundance and nature of feldspar.Shock heating not only decreases the level of natural TL in meteorites,but also destroys the TL phosphor resulting in a decrease in the TL sensitivity of meteorites. Metamorphism generates feldspar through the devitrification of primary igneous glass and causes TL sensitivity to increase by a factor of ～10 5 in ordinary chondrites.The measurement of TL sensitivity has produced new means of classification for 3 type of ordinary chondrites,CO,CV chondrites and eucrites.The peak temperature and peak width of the induced TL curve are also related with the thermal history of meteorites. Relative to disordering of feldspar-which is the TL phosphor, they increase with increasing metamorphism so that these parameters can be used to obtain an estimate of the metamorphic equilibration temperatures. New TL research data of meteorites have been used to discuss the ejection of the shergottites from Mars and earth moon transit times,weathering of Antarctic meteorites and possible differences in extraterrestrial sources.