气候变化领域集成服务门户(CCPortal): Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates

CCPortal

DOI	10.5194/tc-7-1073-2013
	Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates
	Luetscher M.; Borreguero M.; Moseley G.E.; Spötl C.; Edwards R.L.
发表日期	2013
ISSN	19940416
卷号	7 期号:4
英文摘要	Coarse crystalline cryogenic cave carbonates (CCCcoarse) dated to the last glacial period are common in central European caves and provide convincing evidence of palaeo-permafrost during this time. Little is known, however, about the exact nature of the environment in which CCCcoarse formed as no modern analogue setting is known. Here, we report the first findings of sub-recent, albeit inactive, CCCcoarse from a cave of the Western Alps which is located in the present-day permafrost zone. The globular shape and the presence of ubiquitous euhedral crystal terminations are comparable to previously reported aggregates from the last glacial period and strongly suggest that these aggregates formed subaqueously in pools lacking agitation. Furthermore, stable isotope values of mm-sized spheroids point to calcite precipitation in a closed system with respect to CO2, strongly supporting the hypothesis of a cryogenic origin associated with the freezing of water ponds. U-series analyses revealed three clusters of late Holocene calcite precipitation intervals between 2129 and 751 a b2k. These ages correlate with known periods of elevated summer temperatures, suggesting that warming and thawing of the frozen catchment above the cave allowed water infiltration into the karst system. The growth of CCCcoarse resulted from the re-freezing of this water in the still cold karst cavities. © Author(s) 2013.
学科领域	alpine environment; carbonate; cave deposit; cavitation; Last Glacial; paleoenvironment; permafrost; precipitation (chemistry); thawing; Alps; Europe
语种	英语
scopus关键词	alpine environment; carbonate; cave deposit; cavitation; Last Glacial; paleoenvironment; permafrost; precipitation (chemistry); thawing; Alps; Europe
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/120289
作者单位	Institute of Geology, University of Innsbruck, Innsbruck, Austria; Corcelles, Switzerland; Department of Geology and Geophysics, University of Minnesota, MN, United States
推荐引用方式 GB/T 7714	Luetscher M.,Borreguero M.,Moseley G.E.,et al. Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates[J],2013,7(4).
APA	Luetscher M.,Borreguero M.,Moseley G.E.,Spötl C.,&Edwards R.L..(2013).Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates.Cryosphere,7(4).
MLA	Luetscher M.,et al."Alpine permafrost thawing during the Medieval Warm Period identified from cryogenic cave carbonates".Cryosphere 7.4(2013).