An ikaite record of late Holocene climate at the Antarctic Peninsula

作者:Lu Zunli*; Rickaby Rosalind E M; Kennedy Hilary; Kennedy Paul; Pancost Richard D; Shaw Samuel; Lennie Alistair; Wellner Julia; Anderson John B
来源:Earth and Planetary Science Letters, 2012, 325: 108-115.
DOI:10.1016/j.epsl.2012.01.036

摘要

Calcium carbonate can crystallize in a hydrated form as ikaite at low temperatures. The hydration water in ikaite grown in laboratory experiments records the delta O-18 of ambient water, a feature potentially useful for reconstructing delta O-18 of local seawater. We report the first downcore delta O-18 record of natural ikaite hydration waters and crystals collected from the Antarctic Peninsula (AP), a region sensitive to climate fluctuations. We are able to establish the zone of ikaite formation within shallow sediments, based on porewater chemical and isotopic data. Having constrained the depth of ikaite formation and delta O-18 of ikaite crystals and hydration waters, we are able to infer local changes in fjord delta O-18 versus time during the late Holocene. This ikaite record qualitatively supports that both the Medieval Warm Period and Little Ice Age extended to the Antarctic Peninsula. Published by Elsevier B.V.

  • 出版日期2012-4-1