Collaborative Research: The Age of Grand Canyon: Applying New Tests to Resolve the 150-year-old Debate

合作研究：大峡谷时代：应用新测试解决 150 年来的争论

• 批准号: 1348007
• 负责人: Karl Karlstrom
• 金额: $ 15.41万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1348007&HistoricalAwards=false
• 关键词: Collaborative; Research; Age; Grand; Canyon

Questions about the age of Grand Canyon, framed by John Wesley Powell in the late 1800s, address the tectonic and landscape evolution of the Grand Canyon region and the tectonic events that have shaped it. Recent papers reinvigorate the debate, and support models for both "old" (70-17 million years) and "young" (5-6 million years) carving of Grand Canyon, with corresponding tectonic models for "old" versus "young" uplift of the Colorado Plateau. Studies supporting the "old" canyon model suggest that an 80-70 million year old east-flowing river, then a 55-30 million year old west-flowing river, incised a canyon in the same location and to nearly the same depth as modern Grand Canyon. In this model, the Colorado River did not play a significant role in excavating Grand Canyon, and the preponderance of tectonic uplift of the Colorado Plateau took place about 70 million years ago. In contrast, "young" canyon models suggest that most of the Grand Canyon has been carved in the last 6 million years once the Colorado River became integrated from the Rocky Mountains to the Gulf of California and that uplift of the Colorado Plateau region has taken place in multiple episodes and may be ongoing due to regional mantle upwelling. This project tests a "paleocanyon resolution" for the Grand Canyon debate in which there are 3 "young" segments, 1 "old" segment, and 1 "intermediate" age segment that collectively provide a record of a complex multi-stage tectonic uplift history for the southwestern U.S. Two complementary methods are used to test this hypothesis. First, apatite triple dating (fission track, (U-Th)/He dating, and 4He/3He analyses) are applied to new samples from each segment to reconstruct cooling paths for rocks and decipher past (now-eroded) landscapes and fault displacements. Second, detrital zircon and sanidine dating of key preserved paleoriver remnants provide essential ground truth to calibrate the thermochronological investigations.The project?s broader significance and importance are enhanced by intense national and international public interest in the Grand Canyon region as one of Earth?s iconic geologic features. The results of this project may change the current paradigm for the incision age of the Grand Canyon. Discussion and resolution of the century-long Grand Canyon debate illustrates the scientific method and progress of science. The project will have significant impacts on student training, increased diversity of the geoscience workforce, outreach to Native American tribes in the region, public informal science education, and increased collaborative progress among diverse geosciences communities.

关于大峡谷年龄的问题由约翰·韦斯利·鲍威尔 (John Wesley Powell) 在 1800 年代末提出，涉及大峡谷地区的构造和景观演化以及塑造它的构造事件。最近的论文重新激发了争论，并支持大峡谷“古老”（70-1700 万年）和“年轻”（5-600 万年）雕刻的模型，以及相应的“古老”与“年轻”隆起的构造模型科罗拉多高原。支持“古老”峡谷模型的研究表明，一条有 80-7000 万年历史的东流河流，然后是一条有 55-3000 万年历史的西流河流，在与现代相同的位置和几乎相同的深度切割了一个峡谷。大峡谷。在这个模型中，科罗拉多河在大峡谷的开凿过程中并没有发挥重要作用，科罗拉多高原的主要构造隆升发生在大约 7000 万年前。相比之下，“年轻”的峡谷模型表明，大峡谷的大部分是在过去 600 万年科罗拉多河从落基山脉整合到加利福尼亚湾以及科罗拉多高原地区发生隆起后雕刻而成的发生多次，并且可能由于区域地幔上升而持续发生。该项目测试了大峡谷争论的“古峡谷分辨率”，其中有 3 个“年轻”段、1 个“老”段和 1 个“中”段，共同提供了复杂的多阶段构造隆升历史的记录对于美国西南部，使用两种互补的方法来检验这一假设。首先，将磷灰石三重测年（裂变径迹、(U-Th)/He 测年和 4He/3He 分析）应用于每个片段的新样本，以重建岩石的冷却路径并破译过去（现已侵蚀）的景观和断层位移。其次，对关键保存的古河遗迹进行碎屑锆石和长石定年，为校准热年代学研究提供了必要的基础事实。作为地球上的大峡谷地区之一，国家和国际公众对大峡谷地区的强烈兴趣增强了该项目更广泛的意义和重要性。标志性地质特征。该项目的结果可能会改变目前大峡谷切割年龄的范式。长达一个世纪的大峡谷争论的讨论和解决说明了科学方法和科学进步。该项目将对学生培训、增加地球科学劳动力的多样性、对该地区美洲原住民部落的推广、公共非正式科学教育以及增加不同地球科学界之间的合作进展产生重大影响。

项目成果

Detrital sanidine 40Ar/39Ar dating confirms <2 Ma age of Crooked Ridge paleoriver and subsequent deep denudation of the southwestern Colorado Plateau

• DOI: 10.1130/ges02319.1
• 发表时间: 2021-01
• 期刊: Geosphere
• 影响因子: 2.5
• 作者: M. Heizler;K. Karlstrom;M. Albonico;R. Hereford;L. Beard;S. Cather;L. Crossey;K. Sundell

Evaluating the Shinumo-Sespe drainage connection: Arguments against the “old” (70–17 Ma) Grand Canyon models for Colorado Plateau drainage evolution

评估 Shinumo-Sespe 排水系统连接：反对科罗拉多高原排水系统演化的“旧”（70-17 Ma）大峡谷模型的争论

• DOI: 10.1130/ges02265.1
• 发表时间: 2020
• 期刊: Geosphere
• 影响因子: 2.5
• 作者: Karlstrom, Karl E.;Jacobson, Carl E.;Sundell, Kurt E.;Eyster, Athena;Blakey, Ron;Ingersoll, Raymond V.;Mulder, Jacob A.;Young, Richard A.;Beard, L. Sue;Holland, Mark E.
• 通讯作者: Holland, Mark E.