COLLABORATIVE RESEARCH: Testing hypotheses for Late Devonian biotic and climatic events via high-precision CA-TIMS U-Pb zircon dating and quantitative correlation tools

合作研究：通过高精度 CA-TIMS U-Pb 锆石测年和定量相关工具检验晚泥盆世生物和气候事件的假设

• 批准号: 1124488
• 负责人: Mark Schmitz
• 金额: $ 15万
• 依托单位: Boise State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1124488&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Testing; hypotheses; Late

COLLABORATIVE RESEARCH: Testing hypotheses for Late Devonian biotic and climatic events via high-precision CA-TIMS U-Pb zircon dating and quantitative correlation toolsMark Schmitz, EAR-1124488Boise State UniversityD. Jeffrey Over, EAR-1124275SUNY GeneseoABSTRACT The Late Devonian period hosts a series of global biological extinction events of such magnitude as to be counted among the major mass extinctions of the Phanerozoic. Yet no consensus has yet been reached regarding the causative mechanisms of extinction and associated changes in marine sedimentation, biogeochemical cycling, sea level and climate. Testing of competing hypotheses for Late Devonian extinctions?which include sea-level fluctuations and regression, climatic cooling, ocean anoxia, bolide impact, and/or massive volcanism?is currently hampered by a lack of sufficient temporal resolution in paleobiological, tectonic and proxy climate records.In this study, a multi-disciplinary research team of paleontologists, biostratigraphers and isotope geochemists will combine high-precision U-Pb zircon geochronology on interstratified volcanic ash beds in key stratigraphic successions with quantitative biostratigraphy applied to a global Late Devonian multi-taxa database compiled from the literature and new high-resolution sampling. The U-Pb geochronology will utilize the chemical abrasion and EARTHTIME quadruple spike isotope dilution methods to measure ca 0.1 Ma resolution ages, which will calibrate the construction of the first highly resolved composite standard for the Late Devonian via constrained optimization. With this high resolution age model the research team will interrogate several fundamental questions relating to the abruptness of the late Devonian biotic events, their global synchrony, and process drivers. Specific hypotheses to be addressed include the synchrony and causality between extraterrestrial impacts or massive volcanism and biotic crises, whether the rates of associated eustatic rise and fall and fluctuations in proxy records of carbon cycling and temperature are consistent with Milankovich-band orbital forcing, and if feedbacks between climate, glacioeustasy, ocean anoxia, and the carbon cycle caused the Late Devonian biotic crises.This research will impact STEM human resource development via participation of undergraduate students in a multi-disciplinary international science team; develop international scientific collaborations; support the science mission of the EARTHTIME geochronology initiative, and its associated inreach and outreach programs; provide fundamentally improved chronologies for numerous other Paleozoic climate studies; and improve our understanding of deep time climate state transitions potentially analogous to those leading to our current icehouse. The scientific process and content of the proposed research will be captured by a parallel NSF-funded STEM education initiative developing a series of web-based learning objects to teach the science of geochronology and Earth history.

协作研究：通过高精度CA-TIMS U-PB锆石约会和定量相关工具标记Schmitz，EAR-1124488BOISE State D.杰弗里（Jeffrey），EAR-1124275Suny geneseoabstract the Devonian时期晚些时候举办了一系列全球生物灭绝事件，这些事件的幅度为大小，以计算在Phanerozoic的主要质量灭绝中。然而，关于灭绝的病因以及海洋沉积，生物地球化学循环，海平面和气候的相关变化，尚未达成共识。测试对泥盆纪晚期灭绝的竞争假设的测试？哪个包括海平面波动和回归，气候冷却，海洋缺氧，野火山的影响和/或大规模的火山作用？目前缺乏在这个研究的生物学，构造和统治者中缺乏足够的时间分辨率，在这个研究中，是一个研究的生物学研究者，多阶级的研究团队。地球化学家将在关键地层演讲中的地层灰床上的高精度U-PB锆石地质学与应用于全球晚期的泥盆纪多核数据库的定量生物地层学上，该数据库从文献和新的高分辨率采样中汇编而成。 U-PB地质学将利用化学磨损和Earth Time四倍的同位素稀释方法来测量CA 0.1 MA分辨率年龄，这将通过受约束优化的优化校准晚期泥盆纪晚期的高度分辨复合标准的构建。通过这种高分辨率年龄模型，研究团队将询问与已故泥盆纪生物事件的突然性，其全球同步和过程驱动因素有关的几个基本问​​题。 Specific hypotheses to be addressed include the synchrony and causality between extraterrestrial impacts or massive volcanism and biotic crises, whether the rates of associated eustatic rise and fall and fluctuations in proxy records of carbon cycling and temperature are consistent with Milankovich-band orbital forcing, and if feedbacks between climate, glacioeustasy, ocean anoxia, and the carbon cycle caused the Late Devonian biotic危机。这项研究将通过本科生参与多学科国际科学团队的参与来影响STEM人力资源的发展；发展国际科学合作；支持地球年代学计划的科学使命及其相关的侵权和外展计划；为许多其他古生代气候研究提供了从根本上改善的年表；并提高我们对深度气候状态过渡的理解可能类似于导致我们当前冰屋的人。拟议研究的科学过程和内容将由一项平行的NSF资助的STEM教育计划捕获，开发了一系列基于网络的学习对象，以教授地年代学和地球历史科学。

项目成果

Recalibrating the Devonian time scale: A new method for integrating radioisotopic and astrochronologic ages in a Bayesian framework

重新校准泥盆纪时间尺度：在贝叶斯框架中整合放射性同位素和天文年代学年龄的新方法

• DOI: 10.1130/b36128.1
• 发表时间: 2021
• 期刊: GSA Bulletin
• 作者: Harrigan, Claire O.;Schmitz, Mark D.;Over, D. Jeffrey;Trayler, Robin B.;Davydov, Vladimir I.
• 通讯作者: Davydov, Vladimir I.