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: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=628509
• 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。黄土、冰川以及冰层沉积物是育空地区特有的古气候指标连续体的一部分。尽管如此，过去的气候过程仍然被这些特征的地质年龄限制不严所掩盖。该研究计划的重点是开发长石矿物的通用发光测年方法。本文的目标和方法要求这项研究的很大一部分将受益于在育空地区进行。发光现象学将在现代沉积物上进行测试，例如在育空地区南部的圣埃利亚斯山脉冰原山脉中发现的沉积物，更具体地说是在两个逐渐消失的冰川（Kaskawulsh 和 Lowell）的边缘环境附近发现的沉积物。还将对化石冰楔中碎屑碎片的年代测定进行研究，以测试有关这些冰缘特征中的一些年龄的想法。最后，对前冰限的黄土进行年代测定将有助于更好地了解育空地区的冰川和古气候历史。该研究计划应有助于评估第四纪永久冻土的稳定性。研究与传统知识的整合是制定更好的解决方案的关键，以确保在一个永远不一样的世界中确保健康和社会安宁。