Natural Thermoluminescence (NTL) Data for Antarctic Meteorites

Jason Slinker, Paul Benoit, and Derek Sears
Cosmochemistry Group
Dept. of Chemistry and Biochemistry
University of Arkansas
Fayetteville, AR 72701

The measurement and data reduction methods were described by Hasan et al. (1987, Proc. 17th LPSC E703-E709); 1989, LPSC XX, 383-384). For meteorites whose TL lies between 5 and 100 krad, the natural TL is related primarily to terrestrial history. Samples with NTL <5 krad have TL levels below that which can reasonably be ascribed to long terrestrial ages. Such meteorites have had their TL lowered by heating within the last million years of so by close solar passage, shock heating, or atmospheric entry, exacerbated in the case of some achondrites by anomalous fading. We suggest meteorites with NTL >100 krad are candidates for unusual orbital/thermal histories (Benoit and Sears, 1993, EPSL, 120, 463-471).

Sample Class Natural TL
[krad at 250° C]

EET96135

EH4-5

52

     

EET96058

H5

2.10.1

EET96134

H5

1.60.2

     

EET96139

H6

74.80.3

EET96186

H6

96.40.2

     

MET96503

L3.6

11.06.0

     

MET96504

L5

60.40.2

     

EET96130

L6

16.50.1

EET96132

L6

61.80.6

EET96136

L6

104.00.1

EET96140

L6

1.20.2

EET96270

L6

7.70.1

EET96271

L6

30.40.1

EET96273

L6

10.60.1

EET96274

L6

1912

EET96313

L6

26.20.6

EET96313

L6

57.30.6

EET96316

L6

782

EET96330

L6

61.60.3

EET96332

L6

54.40.1

EET96333

L6

44

EET96340

L6

29.60.1

EET96351

L6

0.80.5

MET96501

L6

35.60.1

MET96502

L6

0.30.1

     

EET96137

LL6

10.40.1

     

EET96293

URE

21

The quoted uncertainties are the standard deviations shown by replicate measurements on a single aliquot.

COMMENTS: The following comments are based on natural TL data, TL sensitivity, the shape of the induced TL glow curve, classifications, and JSC and Arkansas sample descriptions.

EET96333 has very low TL sensitivity relative to Dhajala, and is probably highly shocked.

TL sensitivity for MET96503 is similar to a type 3.1. It is possible this meteorite is highly shocked.

1.Pairings suggested by TL data: