Collaborative Research: Equatorial Glaciation and Landscape Burial in the Late Paleozoic: Implications for Pangaean Climate and Tectonics

合作研究：晚古生代赤道冰川作用和景观埋藏：对盘古大陆气候和构造的影响

• 批准号: 1849425
• 负责人: Anders Noren
• 金额: $ 9.96万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1849425&HistoricalAwards=false
• 关键词: Collaborative; Research; Equatorial; Glaciation; Landscape

Climate has varied widely through Earth history. Just as study of human history helps humankind better understand our future, study of Earth's climate history aids in better understanding current and future climate systems. This study is examining whether glaciers existed near Earth's equator at low elevations some 300 million years ago. First, seismic instruments are used to see below the ground surface of Unaweep Canyon (Colorado); this canyon was located near the equator 300 million years ago and now contains features that suggest ancient glaciers may have existed during that time. Peering below the ground surface allows researchers to see the canyon shape and features, including the amount of sediment fill. Next, researchers drill out core samples from the sediment. Detailed analyses of this sediment can reveal the age of the canyon, the past climate of the region, including whether glaciers existed, and how the present-day landscape formed. If it is determined that glaciers existed in this region millions of years ago, understanding of the climate system during that time would need major revision. Computer climate models then help researchers understand characteristics of winds, ocean temperatures, volcanic eruptions, and plant cover needed to produce the climate signal revealed in the core samples. This project includes education for high-school students from the Southern Ute Indian tribe, career training and preparation for university students, and collaboration with art students to create displays and presentations about the research results.This work tests the hypothesis that low-elevation uplands of equatorial Pangaea hosted glaciers during the Late Paleozoic. To test this, geophysics, thermochronology, and coring are used to determine the depth and nature of sediment fill and 3D basement shape of Unaweep Canyon (Colorado), a globally unique landform hypothesized to archive a paleolandscape modified by Permo-Pennsylvanian equatorial glaciation. Evidence for low-latitude glaciation would radically change understanding of the late Paleozoic icehouse, a critical interval for evolution of land animals and plants, and spur research on influences of alternative boundary conditions, climate forcings, and model configurations. Documenting an upland glacial landscape preserved for 300 (or possibly 600) My would also significantly challenge understanding of landscape genesis, evolution, and burial, and feedbacks between tectonics and climate. This research involves outreach to secondary-school students from the Southern Ute Indian tribe, training of STEM undergraduate and graduate students, and interfacing with art students to create impactful public outreach.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在地球历史上，气候变化很大。正如对人类历史的研究有助于人类更好地了解我们的未来一样，对地球气候历史的研究也有助于更好地了解当前和未来的气候系统。这项研究正在研究大约 3 亿年前地球赤道附近低海拔地区是否存在冰川。首先，使用地震仪器观察Unaweep Canyon（科罗拉多州）的地表以下情况；这个峡谷位于三亿年前的赤道附近，现在的特征表明古代冰川可能在那个时期就存在过。通过观察地表以下，研究人员可以看到峡谷的形状和特征，包括沉积物填充量。接下来，研究人员从沉积物中钻出岩心样本。对这些沉积物的详细分析可以揭示峡谷的年龄、该地区过去的气候，包括冰川是否存在，以及当今景观的形成方式。如果确定数百万年前该地区存在冰川，那么对当时气候系统的理解将需要重大修改。然后，计算机气候模型可以帮助研究人员了解产生核心样本中揭示的气候信号所需的风、海洋温度、火山喷发和植物覆盖的特征。该项目包括对南尤特印第安部落高中生的教育、对大学生的职业培训和准备，以及与艺术学生合作制作有关研究成果的展示和演示。这项工作检验了低海拔高地的假设赤道盘古大陆在晚古生代有冰川。为了测试这一点，使用地球物理学、热年代学和取芯来确定乌纳威普峡谷（科罗拉多州）沉积物填充的深度和性质以及 3D 基底形状，这是一种全球独特的地貌，假设记录了二叠纪-宾夕法尼亚赤道冰川作用所改变的古景观。低纬度冰川作用的证据将从根本上改变对晚古生代冰室（陆地动植物进化的关键时期）的理解，并促进对替代边界条件、气候强迫和模型配置影响的研究。记录保存了 300 年（或可能 600 年）的高地冰川景观也将极大地挑战对景观起源、演化、埋藏以及构造与气候之间反馈的理解。这项研究涉及对南尤特印第安部落的中学生进行推广、对 STEM 本科生和研究生进行培训，以及与艺术学生进行互动以创造有影响力的公共推广。该奖项反映了 NSF 的法定使命，并通过评估被认为值得支持利用基金会的智力优势和更广泛的影响审查标准。