Collaborative Research: Terrestrial Late Permian to Early Triassic Earth Systems in NE Pangea: Insights into the Tempo, Effects, and Causes of the End-Permian Mass Extinction

合作研究：盘古大陆东北部的陆地晚二叠世至早三叠世地球系统：深入了解二叠纪末大规模灭绝的节奏、影响和原因

• 批准号: 1714928
• 负责人: John Geissman
• 金额: $ 25.76万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1714928&HistoricalAwards=false
• 关键词: Collaborative; Research; Terrestrial; Late; Permian

ABSTRACTA non-technical description explaining the broader significance of the projectMajor mass extinctions have occurred at various times throughout Earth history. The most well-known of these happened with the demise of the dinosaurs at the end of the Cretaceous Period, but it is believed that the largest mass extinction happened at the end of the Permian Period, approximately 252 million years ago. The extinction in the marine realm was global and occurred over a relatively short time interval. However, events in the terrestrial environment are only sparsely documented. This project will examine well-exposed sedimentary rock successions that formed in lakes, rivers, and ancient soils during the time of these extinctions. This research will enable a precise documentation of the sequence of events on land, a comprehensive analysis of the environmental changes that took place before, during and after the event, and an investigation of how terrestrial animals and plants responded to these changes. The results will determine if extinctions on the continents occurred at the same time as those in the ocean and what conditions existed that may have caused such large-scale changes. Given current concern about rates of extinction, knowledge of the processes that occurred in the past will help identify the reasons behind major changes in flora and fauna. The project will develop museum exhibits and outreach programs to inform both educational and general audiences.A technical description of the projectA comprehensive, multidisciplinary investigation of critical intervals of Earth history offers the best insights into the conditions that prevailed before, during, and after major biotic crises. The Permo-Triassic Mass Extinction is used as a model of how biological and physical systems responded to major climate changes, including those attributable to increasing greenhouse gases. Currently, the Permo-Triassic Mass Extinction is interpreted as a coupled catastrophic collapse of marine and terrestrial ecosystems, both of which experienced protracted restructuring of ecological communities and recovery of stable ecosystem dynamics. The Bogda Mountains in China contain a fully continental stratigraphy spanning the critical interval wherein fluvial and lacustrine deposits alternate with an extensive paleosol record, from which pedogenic trends and geochemical models can be derived. A paleontological record including major plant and animal groups is well-preserved. Pilot-project data show the preservation of a primary magnetization in rocks in the section, from which a robust magnetic polarity stratigraphy can be derived. There are also numerous volcanic deposits that contain primary volcanic zircons spanning the critical interval. These will be used to obtain high precision ages to establish a careful chronology. Together, these data allow evaluation of environmental and ecosystem changes that took place during the Permian-Triassic transition. Research results will be integrated into curricula at each participating academic institution, and summer outreach programs will be offered to high-school science teachers. Five educational videos will be developed for the Field Museum's award winning "The Brain Scoop" YouTube channel. Data visualizations of analytical and model results will be developed for informal education outreach in conjunction with the Visualization Studio at the California Academy of Sciences.

摘要非技术描述解释了该项目的更广泛意义在整个地球历史的不同时期都发生过重大的大规模灭绝。其中最著名的一次是白垩纪末期恐龙的灭亡，但据信最大规模的灭绝发生在二叠纪末期，即大约 2.52 亿年前。海洋领域的灭绝是全球性的，并且发生在相对较短的时间间隔内。然而，陆地环境中发生的事件却很少有记录。该项目将检查在这些灭绝期间在湖泊、河流和古代土壤中形成的暴露良好的沉积岩序列。这项研究将能够精确记录陆地上事件的顺序，全面分析事件之前、期间和之后发生的环境变化，并调查陆地动植物如何应对这些变化。结果将确定大陆上的灭绝是否与海洋中的灭绝同时发生，以及存在哪些条件可能导致如此大规模的变化。鉴于当前对灭绝速度的担忧，了解过去发生的过程将有助于确定动植物群重大变化背后的原因。该项目将开发博物馆展览和推广计划，以向教育界和普通观众提供信息。该项目的技术描述对地球历史关键时期进行全面、多学科的调查，提供对主要生物发生之前、期间和之后普遍存在的条件的最佳见解危机。二叠纪-三叠纪大规模灭绝被用作生物和物理系统如何应对重大气候变化（包括因温室气体增加而导致的气候变化）的模型。目前，二叠纪-三叠纪大规模灭绝被解释为海洋和陆地生态系统的耦合灾难性崩溃，这两个生态系统都经历了长期的生态群落重组和稳定的生态系统动态的恢复。中国博格达山脉包含跨越关键区间的完全大陆性地层，其中河流和湖泊沉积物与广泛的古土壤记录交替出现，从中可以得出成土趋势和地球化学模型。包括主要动植物群的古生物学记录保存完好。试点项目数据显示该剖面岩石中保存了原始磁化强度，从中可以得出可靠的磁极性地层学。还有许多火山矿床含有跨越临界层段的原生火山锆石。这些将用于获得高精度年龄以建立仔细的年表。 总之，这些数据可以评估二叠纪-三叠纪过渡期间发生的环境和生态系统变化。研究成果将被纳入每个参与学术机构的课程中，并将为高中科学教师提供暑期外展计划。将为菲尔德博物馆获奖的“The Brain Scoop”YouTube 频道制作五个教育视频。将与加州科学院的可视化工作室一起开发分析和模型结果的数据可视化，用于非正式教育推广。