Dating loess up to 800 ka by thermoluminescence
- Western Washington Univ., Bellingham (United States)
- Victoria Univ., Wellington (New Zealand)
- Massey Univ., Palmerston North (New Zealand)
Thermoluminescence (TL) ages agreeing with expected ages have been obtained for 13 loess samples spanning the age range from 20 to 800 ka. The authors samples are from Alaska and North Island, New Zealand, and are unusual in TL dating studies of loess older than 80-100 ka by having independent age assignments that are generally well constrained, from ages of associated tephra beds. With the polymineral fine-silt-sized (4-11 {mu}m) grains the partial-bleach TL technique yielded expected ages up to about 350 ka, whereas the total-bleach method gave accurate ages in the range 100 to 800 ka. Thus, the much disputed upper age limit of 100-150 ka for the TL dating of loess now appears to be sample and worker dependent, rather than a global property of the TL signals in the TL-dominant feldspars.
- OSTI ID:
- 7202237
- Journal Information:
- Geology; (United States), Vol. 20:5; ISSN 0091-7613
- Country of Publication:
- United States
- Language:
- English
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