气候变化领域集成服务门户(CCPortal): The micromorphology of glaciolacustrine varve sediments and their use for reconstructing palaeoglaciological and palaeoenvironmental change

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DOI	10.1016/j.quascirev.2019.105964
	The micromorphology of glaciolacustrine varve sediments and their use for reconstructing palaeoglaciological and palaeoenvironmental change
	Palmer A.P.; Bendle J.M.; MacLeod A.; Rose J.; Thorndycraft V.R.
发表日期	2019
ISSN	0277-3791
卷号	226
英文摘要	Former glaciolacustrine systems are an important archive of palaeoglaciological, palaeoenvironmental and palaeoclimatic change. The annually laminated (varved) sediments that, under certain conditions, accumulate in former glacial lakes, offer a rare opportunity to reconstruct such changes (e.g. glacier advance and retreat cycles, glacier ablation trends, permafrost melt, nival events) at annual or even sub-annual temporal resolution. Data of this kind are desirable for their ability to guide and test numerical model simulations of glacier dynamics and palaeoclimatic change that occur over rapid time intervals, with implications for predicting future glacier response to climatic change, or the effects of weather and climate events on lake sedimentation. The most valuable records preserved in glaciolacustrine systems are continuous varved sequences formed in the distal parts of glacial lakes, where microscale lamination structures can accumulate relatively undisturbed. Technological advances, in the last few decades, have enabled improved characterisation of glaciolacustrine varve microfacies and the precise measurement of varve thickness at the micrometre scale. However, unlike in cognate fields (e.g. soil science), protocols for the robust and consistent description and interpretation of glaciolacustrine varve sediments are lacking. To fill this gap, and to provide a resource for future studies of glaciolacustrine varved sediments, this paper reviews the processes of sedimentation in glacial lake basins, and presents the defining microfacies characteristics of glacial varves using a descriptive protocol that uses consistent examination of grain size, sorting, structure, nature of contacts, development of plasmic fabrics and features such as dropgrains and intraclasts within individual laminations. These lamination types are then combined into lamination sets, whose structures can be interpreted as glaciolacustrine varves. Within this framework, we define five principal assemblages of glaciolacustrine varve microfacies which, if clearly identified in palaeoglaciolacustrine settings, enable more detailed palaeoenvironmental interpretations to be made. Finally, we discuss the utility and complexities of reconstructing the evolution of former glacial lake systems using varve microfacies and thickness datasets. © 2019
语种	英语
scopus关键词	Climate models; Glacial geology; Lakes; Sediments; Thickness measurement; Climatic changes; Glacier dynamics; Micromorphologies; Numerical model simulations; Precise measurements; Technological advances; Temporal resolution; Time interval; Climate change; ablation; glacier advance; glacier dynamics; glaciolacustrine deposit; lamination; microfacies; micromorphology; numerical model; paleoenvironment; permafrost; sedimentation
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151673
作者单位	Centre for Quaternary Research, Department of Geography, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom; Department of Geography and Environmental Science, The University of Reading, Whiteknights, PO Box 227Reading RG6 6AB, United Kingdom; British Geological Survey, Keyworth, Nottingham, NG12 5GG, United Kingdom
推荐引用方式 GB/T 7714	Palmer A.P.,Bendle J.M.,MacLeod A.,et al. The micromorphology of glaciolacustrine varve sediments and their use for reconstructing palaeoglaciological and palaeoenvironmental change[J],2019,226.
APA	Palmer A.P.,Bendle J.M.,MacLeod A.,Rose J.,&Thorndycraft V.R..(2019).The micromorphology of glaciolacustrine varve sediments and their use for reconstructing palaeoglaciological and palaeoenvironmental change.Quaternary Science Reviews,226.
MLA	Palmer A.P.,et al."The micromorphology of glaciolacustrine varve sediments and their use for reconstructing palaeoglaciological and palaeoenvironmental change".Quaternary Science Reviews 226(2019).