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The Sutter's Mill meteorite: Thermoluminescence data on thermal and metamorphic history
Author(s) -
Sears Derek W.,
Beauford Robert
Publication year - 2014
Publication title -
meteoritics and planetary science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.09
H-Index - 100
eISSN - 1945-5100
pISSN - 1086-9379
DOI - 10.1111/maps.12259
Subject(s) - chondrite , thermoluminescence , meteorite , geology , petrography , mineralogy , metamorphic rock , parent body , geochemistry , analytical chemistry (journal) , materials science , chemistry , astrobiology , physics , optoelectronics , luminescence , chromatography
A piece of the Sutter's Mill meteorite, fragment SM 2‐1d, has been examined using thermoluminescence techniques to better understand its thermal and metamorphic history. The sample had very weak but easily measureable natural and induced thermoluminescence ( TL ) signals; the signal‐to‐noise ratio was better than 10. The natural TL was restricted to the high‐temperature regions of the glow curve suggesting that the meteorite had been heated to approximately 300 °C within the time it takes for the TL signal to recover from a heating event, probably within the last 10 5 years. It is possible that this reflects heating during release from the parent body, close passage by the Sun, or heating during atmospheric passage. Of these three options, the least likely is the first, but the other possibilities are equally likely. It seems that temperatures of approximately 300 °C reached 5 or 6 mm into the meteorite, so that all but one of the small Sutter's Mill stones have been heated. The Dhajala normalized induced TL signal for SM 2‐1d is comparable to that of type 3.0 chondrites and is unlike normal CM chondrites, the class it most closely resembles, which do not have detectable TL sensitivity. The shape of the induced TL curve is comparable to other low‐type ordinary, CV , and CO chondrites, in that it has a broad hummocky structure, but does not resemble any of them in detail. This suggests that Sutter's Mill is a unique, low‐petrographic–type (3.0) chondrite.