Thermoluminescence and Antarctic meteorites
The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. Howev...
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ftnasantrs:oai:casi.ntrs.nasa.gov:19860019356 2023-05-15T13:58:36+02:00 Thermoluminescence and Antarctic meteorites Hasan, F. A. Sears, D. W. G. Unclassified, Unlimited, Publicly available JAN 1, 1986 application/pdf http://hdl.handle.net/2060/19860019356 unknown Document ID: 19860019356 Accession ID: 86N28828 http://hdl.handle.net/2060/19860019356 No Copyright CASI ASTROPHYSICS Lunar and Planetary Inst. International Workshop on Antarctic Meteorites; p 83-100 1986 ftnasantrs 2019-07-21T09:37:13Z The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. However, since a few observed falls have low TL due to a recent heating event, such as passage within approximately 0.7 astronomical units of the Sun, this could also be the case for some Antarctic meteorites. Dose rate variations due to shielding, heating during atmospheric passage, and anomalous fading also cause natural TL variations, but the effects are either relatively small, occur infrequently, or can be experimentally circumvented. The TL sensitivity of meteorites reflects the abundance and nature of the feldspar. Thus intense shock, which destroys feldspar, causes the TL sensitivity to decrease by 1 to 2 orders of magnitude, while metamorphism, which generates feldspar through the devitrification of glass, causes TL sensitivity to increase by a factor of approximately 10000. The TL-metamorphism relationship is particularly strong for the lowest levels of metamorphism. The order-disorder transformation in feldspar also affect the TL emission characteristics and thus TL provides a means of paleothermometry. Other/Unknown Material Antarc* Antarctic NASA Technical Reports Server (NTRS) Antarctic |
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NASA Technical Reports Server (NTRS) |
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ftnasantrs |
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ASTROPHYSICS |
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ASTROPHYSICS Hasan, F. A. Sears, D. W. G. Thermoluminescence and Antarctic meteorites |
topic_facet |
ASTROPHYSICS |
description |
The level of natural thermoluminescence (TL) in meteorites is the result of competition between build-up, due to exposure to cosmic radiation, and thermal decay. Antarctic meteorites tend to have lower natural TL than non-Antarctic meteorites because of their generally larger terrestrial ages. However, since a few observed falls have low TL due to a recent heating event, such as passage within approximately 0.7 astronomical units of the Sun, this could also be the case for some Antarctic meteorites. Dose rate variations due to shielding, heating during atmospheric passage, and anomalous fading also cause natural TL variations, but the effects are either relatively small, occur infrequently, or can be experimentally circumvented. The TL sensitivity of meteorites reflects the abundance and nature of the feldspar. Thus intense shock, which destroys feldspar, causes the TL sensitivity to decrease by 1 to 2 orders of magnitude, while metamorphism, which generates feldspar through the devitrification of glass, causes TL sensitivity to increase by a factor of approximately 10000. The TL-metamorphism relationship is particularly strong for the lowest levels of metamorphism. The order-disorder transformation in feldspar also affect the TL emission characteristics and thus TL provides a means of paleothermometry. |
format |
Other/Unknown Material |
author |
Hasan, F. A. Sears, D. W. G. |
author_facet |
Hasan, F. A. Sears, D. W. G. |
author_sort |
Hasan, F. A. |
title |
Thermoluminescence and Antarctic meteorites |
title_short |
Thermoluminescence and Antarctic meteorites |
title_full |
Thermoluminescence and Antarctic meteorites |
title_fullStr |
Thermoluminescence and Antarctic meteorites |
title_full_unstemmed |
Thermoluminescence and Antarctic meteorites |
title_sort |
thermoluminescence and antarctic meteorites |
publishDate |
1986 |
url |
http://hdl.handle.net/2060/19860019356 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
CASI |
op_relation |
Document ID: 19860019356 Accession ID: 86N28828 http://hdl.handle.net/2060/19860019356 |
op_rights |
No Copyright |
_version_ |
1766266964917878784 |