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

在地球历史上，气候变化很大。正如研究人类历史有助于人类更好地了解我们的未来一样，研究地球气候历史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3亿年前在低海拔的地球赤道附近是否存在冰川。首先，地震仪器被用来观察科罗拉多州尤纳韦普峡谷(Unaweep Canyon)地表以下的情况；这个峡谷位于3亿年前的赤道附近，现在包含的特征表明，在此期间可能存在古代冰川。通过观察地表以下，研究人员可以看到峡谷的形状和特征，包括沉积物的充填量。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，包括是否存在冰川，以及今天的景观是如何形成的。如果确定该地区在数百万年前就存在冰川，那么对那段时间气候系统的理解将需要进行重大修改。然后，计算机气候模型帮助研究人员了解风、海洋温度、火山喷发和植物覆盖的特征，这些特征是产生核心样本中揭示的气候信号所需的。该项目包括对南犹特印第安人部落的高中生的教育，对大学生的职业培训和准备，以及与艺术专业的学生合作，以展示和展示研究成果。这项工作检验了晚古生代赤道盘古高原低海拔高原有冰川的假设。为了验证这一点，使用地球物理、热年代学和岩心来确定沉积物填充的深度和性质以及科罗拉多州Unaweep Canyon(科罗拉多州)的3D基底形状，Unaweep Canyon(科罗拉多州)是一种全球唯一的地貌，假设记录了被二叠纪-宾夕法尼亚赤道冰川修改的古兰地景观。低纬冰川作用的证据将从根本上改变对晚古生代冰库的理解，晚古生代冰库是陆地动植物进化的关键时期，并推动对不同边界条件、气候强迫和模型配置的影响的研究。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、埋葬以及构造和气候之间反馈的理解。这项研究涉及到南犹他州印第安人部落的中学生，STEM本科生和研究生的培训，以及与艺术学生的互动，以创造有影响力的公共外向。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.