Antarctic Meteorite Newsletter, Volume 24, No. 1 - February 2001
Volume 24, No. 1 - February 2001

Table 4: Natural Thermoluminescence (NTL) Data for Antarctic Meteorites

Paul H. Benoit and Derek W.G. Sears

Cosmochemistry Group

University of Arkansas

Fayetteville, AR 72701 USA

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 or 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]

 

ALH 97101

H5

0.7 0.1

ALH 97102

H5

39.4 0.3

     

GRA 98186

H6

39.8 0.5

     

SCO 98200

L4

3.5 0.1

     

ALH 97100

L6

22.5 0.1

LEW 97204

L6

12.4 0.1

LEW 97205

L6

11.6 0.1

LEW 97207

L6

9.7 0.1

LEW 97210

L6

12.3 0.1

LEW 97212

L6

9 1

SCO 98201

L6

6.9 0.2

     

LEW 97213

LL5

5.5 0.1

QUE 97805

LL5

0.4 0.1

QUE 97807

LL5

4.0 0.1

QUE 97811

LL5

17.0 0.1

QUE 97840

LL5

3.2 0.1

     

LEW 97203

LL6

7.6 0.1

LEW 97206

LL6

4.9 0.1

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.

LEW 97207 (L6) has very low TL sensitivity and may be highly shocked.

Pairings suggested by TL data: