LUMINESCENCE DATING OF CLIMATE-SENSITIVE SEDIMENTS IN YUKON

育空地区气候敏感沉积物的发光测年

• 批准号: 362077-2013
• 负责人: Lamothe, Michel
• 金额: $ 1.09万
• 依托单位: Université du Québec à Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Northern Research Supplement
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=572790
• 关键词: LUMINESCENCE; DATING; CLIMATE; SENSITIVE; SEDIMENTS

In the Canadian North, the most economically and socially threatening impact of Global Warming in centuries to come will be the degradation of permafrost. Yukon is known to host sedimentary archives that could be used to interpret past sensitivity of physical environments to climate change. Among those, fossil ice wedges are probably the most spectacular witnesses of past climate conditions. Loess, glaciers as well as glacial deposits indicators of former ice limits are part of a continuum of paleoclimate proxies that are unique to Yukon. Past climate processes are nonetheless obscured by the poorly constrained geological age of these features. This research proposal is focused on the development of a universal luminescence dating method for feldspar minerals. The objectives and methodology herein require a large part of this research would benefit from being carried out in Yukon. Luminescence phenomenology will be tested on modern sediments, as those found in the St. Elias Mountains Ice Field Ranges of Southern Yukon, more specifically near the marginal environments of two waning glaciers (Kaskawulsh and Lowell). Research will also be conducted on the dating of detrital debris in fossil ice wedges in order to test ideas about the ages of some of these periglacial features. Finally, dating loess at former ice limits will contribute to better understand the glacial and paleoclimate history of Yukon. This research program should contribute to evaluate the stability of permafrost across the Quaternary. The integration of research and Traditional Knowledge is key to elaborate better solutions to secure health and social serenity in a world that will never be the same.

在加拿大北部，未来几个世纪全球变暖对经济和社会最具威胁的影响将是永久冻土的退化。众所周知，育空地区拥有沉积档案，可用于解释过去物理环境对气候变化的敏感性。其中，冰楔化石可能是过去气候条件最壮观的见证者。黄土、冰川以及冰川沉积物是前冰限的标志，是育空地区独有的一系列古气候代用指标的一部分。然而，过去的气候过程被这些特征的地质年龄所掩盖。 本研究旨在建立一种通用的长石矿物释光测年方法。本文的目标和方法要求在育空地区进行这项研究的很大一部分将受益。将在现代沉积物上测试发光现象学，如在南育空地区圣埃利亚斯山冰原山脉发现的沉积物，更具体地说，是在两个逐渐消失的冰川（Kaskawulsh和Lowell）的边缘环境附近。还将研究冰楔化石中碎屑的年代，以检验关于这些冰缘地貌的一些年代的想法。最后，在前冰限的黄土测年将有助于更好地了解育空地区的冰川和古气候历史。这一研究计划将有助于评估跨越第四纪多年冻土的稳定性。研究与传统知识的结合是制定更好的解决方案的关键，以确保在一个永远不会相同的世界中的健康和社会安宁。