Natural Thermoluminescence (NTL) Data for Antarctic Meteorites
Paul Benoit, Joyce Roth, Hazel Sears, 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 below that which can be reasonably ascribed to long terrestrial ages Such meteorites have had their TL lowered by heating within the past million years or so by close solar passage, shock heating, or atmospheric entry We suggest that meteorites with NTL >100 krad are candidates for unusual orbital/thermal histories (Benoit and Sears, 1993, EPSL 120, 463-471).
NTL
[krad at
Sample Class 250 deg. C]
QUE93030 H3 66.8±0.6
QUE93024 H5 48.2±0.5
QUE93027 H5 0.34±0.04
QUE93028 H5 1 ±0.1
QUE93029 H5 27.5±0.1
QUE93033 H5 24.3±0.1
QUE93034 H5 0.9±0.1
QUE93038 H5 53 ±0.3
QUE93043 H5 22.8±0.1
QUE93046 H5 107.1±0.1
QUE93049 H5 22.9±0.1
QUE93051 H5 1.9±0.3
QUE93055 H5 5.1±0.1
QUE93031 L5 8.1±0.1
QUE93032 L5 2.1±0.3
QUE93035 L5 12.6±0.1
QUE93036 L5 9.9±0.5
QUE93037 L5 0.5±0.1
QUE93039 L5 10.3±0.2
QUE93040 L5 13.4±0.1
QUE93041 L5 3.1±0.1
QUE93042 L5 8.8±0.1
QUE93044 L5 8.8±0.1
QUE93045 L5 33 ±2
QUE93052 L5 14.8±0.2
QUE93053 L5 2.8±0.4
QUE93054 L5 0.7±0.1
QUE93056 L5 15.5±0.1
QUE93057 L5 8.3±0.1
QUE93058 L5 9.7±0.1
QUE93059 L5 9.6±0.1
QUE93061 L5 10.3±0.1
QUE93062 L5 1.9±0.2
QUE93063 L5 8.7±0.1
QUE93065 L5 2.7±0.5
QUE93068 L5 5.2±0.2
QUE93072 L5 1.6±0.3
QUE93076 L5 12.2±0.1
QUE93016 L6 30.9±0.3
RKP92407 L6 33.5±0.2
RKP92408 L6 89 ±2
The quoted uncertainties are the standard deviation shown by replicate measurements of a single aliquot.
COMMENTS: The following comments are based on natural TL data, TL senstivity, the shape of the induced glow curve, classifications, and JSC and Arkansas group sample descriptions.
QUE93030 is confirmed as a type 3.6 (AMN 18:1).
1. Pairings (Confirmations of pairings in AMN 18(1):
H5: QUE93043, QUE93049 and possibly QUE93029.
L5: QUE93032, QUE93037, QUE93041, QUE93053, QUE93062 and possibly QUE93054 and QUE93065 with QUE90205 group (AMN15:2).
L5: QUE93031, QUE93035, QUE93036, QUE93039, QUE93040, QUE93042, QUE93044, QUE93052, QUE93056, QUE93058, QUE93059, QUE93061 and QUE93076 with QUE90207 group (AMN15:2).
L5: QUE93057 and QUE93063 with QUE90202 (AMN 15:2).
2. TL data do not confirm pairings suggested in the Newsletter:
H5: QUE93038 with QUE93043 group (AMN 18:1).
L5: QUE93045 with QUE90201 group (AMN 18:1).
L5: QUE90218 and QUE90239 with QUE90201 group (AMN 15:1 and 15:2).
3. Additional pairings suggested by TL data:
H5: QUE93051 with QUE93028.
H5: QUE93033 with QUE93043 group.
L5: QUE90218, QUE90239, and QUE93045.