Residual Osl Signals from Modern Greenlandic River Sediments
Residual Osl Signals from Modern Greenlandic River Sediments Ripple-laminated sandy deposits at shallow water depths in four rivers on Jameson Land, East Greenland were sampled for optically stimulated luminescence (OSL) dating. Silt-sized grains have significantly higher equivalent doses (~1.1 Gy)...
Published in: | GEOCHR |
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Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
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Walter de Gruyter GmbH
2007
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Online Access: | http://dx.doi.org/10.2478/v10003-007-0001-6 http://content.sciendo.com/view/journals/geochr/26/-1/article-p1.xml https://www.sciendo.com/pdf/10.2478/v10003-007-0001-6 |
Summary: | Residual Osl Signals from Modern Greenlandic River Sediments Ripple-laminated sandy deposits at shallow water depths in four rivers on Jameson Land, East Greenland were sampled for optically stimulated luminescence (OSL) dating. Silt-sized grains have significantly higher equivalent doses (~1.1 Gy) than sand grains (~0.1 Gy). This suggests that coarse grain-size fractions are better bleached and more suitable than fine grains for OSL dating of glaciofluvial/fluvial sediments. A sample from a sidebar deposited during the spring flood yielded 1.0 Gy (~500 years) while a subaerial deposit was completely zeroed. The spring flood deposit is considered to be most similar to deglacial conditions and incomplete bleaching of this amount (1 Gy) is generally not a significant source of error for sediments of Pleistocene age. Most samples have rather poor luminescence characteristics and are affected by thermal transfer if preheat temperatures at or above 260°C are used. |
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