In:
Climate of the Past, Copernicus GmbH, Vol. 19, No. 4 ( 2023-04-27), p. 851-864
Abstract:
Abstract. We present an age model for the 651 m deep ice core from Skytrain Ice Rise,
situated inland of the Ronne Ice Shelf, Antarctica. The top 2000 years have
previously been dated using age markers interpolated through annual layer
counting. Below this, we align the Skytrain core to the AICC2012 age model
using tie points in the ice and air phase, and we apply the Paleochrono program
to obtain the best fit to the tie points and glaciological constraints. In
the gas phase, ties are made using methane and, in critical sections,
δ18Oair; in the ice phase ties are through 10Be
across the Laschamps event and through ice chemistry related to long-range
dust transport and deposition. This strategy provides a good outcome to
about 108 ka (∼ 605 m). Beyond that there are signs of flow
disturbance, with a section of ice probably repeated. Nonetheless values of
CH4 and δ18Oair confirm that part of the last
interglacial (LIG), from about 117–126 ka (617–627 m), is present and in
chronological order. Below this there are clear signs of stratigraphic
disturbance, with rapid oscillation of values in both the ice and gas phase
at the base of the LIG section, below 628 m. Based on methane values, the
warmest part of the LIG and the coldest part of the penultimate glacial are
missing from our record. Ice below 631 m appears to be of age 〉 150 ka.
Type of Medium:
Online Resource
ISSN:
1814-9332
DOI:
10.5194/cp-19-851-2023
DOI:
10.5194/cp-19-851-2023-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2023
detail.hit.zdb_id:
2217985-9
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