气候变化领域集成服务门户(CCPortal): Hematite reconstruction of late triassic hydroclimate over the Colorado Plateau

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DOI	10.1073/pnas.2004343118
	Hematite reconstruction of late triassic hydroclimate over the Colorado Plateau
	Lepre C.J.; Olsen P.E.
发表日期	2021
ISSN	00278424
卷号	118 期号:7
英文摘要	Hematite is the most abundant surficial iron oxide on Earth resulting from near-surface processes that make it important for addressing numerous geologic problems. While red beds have proved to be excellent paleomagnetic recorders, the early diagenetic origin of hematite in these units is often questioned. Here, we validate pigmentary hematite (“pigmentite”) as a proxy indicator for the Late Triassic environment and its penecontemporaneous origin by analyzing spectrophotometric measurements of a 14.5-My–long red bed sequence in scientific drill core CPCP-PFNP13-1A of the Chinle Formation, Arizona. Pigmentite concentrations in the red beds track the evolving pattern of the Late Triassic monsoon and indicate a long-term rise in aridity beginning at ∼215 Ma followed by increased oscillatory climate change at ∼213 Ma. These monsoonal changes are attributed to the northward drift of the Colorado Plateau as part of Laurentia into the arid subtropics during a time of fluctuating CO2. Our results refine the record of the Late Triassic monsoon and indicate significant changes in rainfall proximal to the Adamanian–Revueltian biotic transition that thus may have contributed to apparent faunal and floral events at 216 to 213 Ma. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Hematite \| monsoon \| red beds \| Triassic \| Pangaea
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180612
作者单位	Department of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ 08854, United States; Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States; Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, United States
推荐引用方式 GB/T 7714	Lepre C.J.,Olsen P.E.. Hematite reconstruction of late triassic hydroclimate over the Colorado Plateau[J],2021,118(7).
APA	Lepre C.J.,&Olsen P.E..(2021).Hematite reconstruction of late triassic hydroclimate over the Colorado Plateau.Proceedings of the National Academy of Sciences of the United States of America,118(7).
MLA	Lepre C.J.,et al."Hematite reconstruction of late triassic hydroclimate over the Colorado Plateau".Proceedings of the National Academy of Sciences of the United States of America 118.7(2021).