气候变化领域集成服务门户(CCPortal): A high-resolution record of early Paleozoic climate

CCPortal

DOI	10.1073/pnas.2013083118
	A high-resolution record of early Paleozoic climate
	Goldberg S.L.; Present T.M.; Finnegan S.; Bergmann K.D.
发表日期	2021
ISSN	00278424
卷号	118 期号:6
英文摘要	The spatial coverage and temporal resolution of the Early Paleozoic paleoclimate record are limited, primarily due to the paucity of well-preserved skeletal material commonly used for oxygen-isotope paleothermometry. Bulk-rock δ18O datasets can provide broader coverage and higher resolution, but are prone to burial alteration. We assess the diagenetic character of two thick Cambro-Ordovician carbonate platforms with minimal to moderate burial by pairing clumped and bulk isotope analyses of micritic carbonates. Despite resetting of the clumped-isotope thermometer at both sites, our samples indicate relatively little change to their bulk δ18O due to low fluid exchange. Consequently, both sequences preserve temporal trends in δ18O. Motivated by this result, we compile a global suite of bulk rock δ18O data, stacking overlapping regional records to minimize diagenetic influences on overall trends. We find good agreement of bulk rock δ18O with brachiopod and conodont δ18O trends through time. Given evidence that the δ18O value of seawater has not evolved substantially through the Phanerozoic, we interpret this record as primarily reflecting changes in tropical, nearshore seawater temperatures and only moderately modified by diagenesis. Focusing on the samples with the most enriched, and thus likely least-altered, δ18O values, we reconstruct Late Cambrian warming, Early Ordovician extreme warmth, and cooling around the Early-Middle Ordovician boundary. Our record is consistent with models linking the Great Ordovician Biodiversification Event to cooling of previously very warm tropical oceans. In addition, our high-temporal-resolution record suggests previously unresolved transient warming and climate instability potentially associated with Late Ordovician tectonic events. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Biodiversification; Ordovician; Oxygen isotope; Paleoclimate
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/180723
作者单位	Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, United States; Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, United States
推荐引用方式 GB/T 7714	Goldberg S.L.,Present T.M.,Finnegan S.,et al. A high-resolution record of early Paleozoic climate[J],2021,118(6).
APA	Goldberg S.L.,Present T.M.,Finnegan S.,&Bergmann K.D..(2021).A high-resolution record of early Paleozoic climate.Proceedings of the National Academy of Sciences of the United States of America,118(6).
MLA	Goldberg S.L.,et al."A high-resolution record of early Paleozoic climate".Proceedings of the National Academy of Sciences of the United States of America 118.6(2021).