Climate archives from 90 to 250ka in horizontal and vertical ice cores from the allan hills blue ice area, antarctica
Publication Year
2013
Type
Journal Article
Abstract
Terrestrial meteorite ages indicate that some ice at the Allan Hills blue ice area (AH BIA) may be as old as 2.2Ma. As such, ice from the AH BIA could potentially be used to extend the ice core record of paleoclimate beyond 800ka. We collected samples from 5 to 10cm depth along a 5km transect through the main icefield and drilled a 225m ice core (S27) at the midpoint of the transect to develop the climate archive of the AH BIA. Stable water isotope measurements (δD) of the surface chips and of ice core S27 yield comparable signals, indicating that the climate record has not been significantly altered in the surface ice. Measurements of 40Aratm and δ18Oatm taken from ice core S27 and eight additional shallow ice cores constrain the age of the ice to approximately 90-250ka. Our findings provide a framework around which future investigations of potentially older ice in the AH BIA could be based. © 2013 University of Washington.
Journal
Quaternary Research (United States)
Volume
80
Pages
562-574