Calcium isotope evidence for environmental variability before and across the Cretaceous-Paleogene mass extinction

Linzmeier, Benjamin J.; Jacobson, Andrew D.; Sageman, Bradley B.; Hurtgen, Matthew T.; Ankney, Meagan E.; Petersen, Sierra V.; Tobin, Thomas S.; Kitch, Gabriella D.; Wang, Jiuyuan

doi:10.1130/g46431.1

Cited by 17 publications

(15 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have highlighted here several issues with the way the 40 Ar/ 39 Ar data have been used to interpret eruption rates of the Deccan Traps, and do so because this misinterpretation has appeared in summaries of the two articles (Burgess, 2019), the popular media (e.g., Voosen, 2019), and in subsequent presentations and papers discussing these datasets (Henehan et al, 2019;Hull et al, 2020;Linzmeier et al, 2020;Milligan et al, 2019;Montanari and Coccioni, 2019). The potential fallout of these misunderstandings is that it risks painting a picture among non-geochronologists that the U−Pb and 40 Ar/ 39 Ar methods cannot agree on the eruption history of the Deccan Traps and that the geological community should be skeptical of geochronology in general.…”

Section: Discussionmentioning

confidence: 99%

“…This was a key message sent by the associated "News and Views" piece in the same issue of Science (Burgess, 2019), and the notion that the U−Pb and 40 Ar/ 39 Ar datasets disagreed substantially has been propagated by subsequent discussion and news coverage on Sci-enceMag.org (Kerr and Ward, 2019;Voosen, 2019). Authors of subsequent papers (Henehan et al, 2019;Hull et al, 2020;Linzmeier et al, 2020;Milligan et al, 2019;Montanari and Coccioni, 2019;Sepúlveda et al, 2019) also seem to conclude that the datasets do not agree on the eruption rates of the Deccan Traps and/or that the dataset of Sprain et al (2019) suggests an inflection in eruption rates of Deccan Traps at the KPB.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

An evaluation of Deccan Traps eruption rates using geochronologic data

et al. 2021

View full text Add to dashboard Cite

Abstract. Recent attempts to establish the eruptive history of the Deccan Traps large igneous province have used both U−Pb (Schoene et al., 2019) and 40Ar/39Ar (Sprain et al., 2019) geochronology. Both of these studies report dates with high precision and unprecedented coverage for a large igneous province and agree that the main phase of eruptions began near the C30n–C29r magnetic reversal and waned shortly after the C29r–C29n reversal, totaling ∼ 700–800 kyr duration. These datasets can be analyzed in finer detail to determine eruption rates, which are critical for connecting volcanism, associated volatile emissions, and any potential effects on the Earth's climate before and after the Cretaceous–Paleogene boundary (KPB). It is our observation that the community has frequently misinterpreted how the eruption rates derived from these two datasets vary across the KPB. The U−Pb dataset of Schoene et al. (2019) was interpreted by those authors to indicate four major eruptive pulses before and after the KPB. The 40Ar/39Ar dataset did not identify such pulses and has been largely interpreted by the community to indicate an increase in eruption rates coincident with the Chicxulub impact (Renne et al., 2015; Richards et al., 2015). Although the overall agreement in eruption duration is an achievement for geochronology, it is important to clarify the limitations in comparing the two datasets and to highlight paths toward achieving higher-resolution eruption models for the Deccan Traps and for other large igneous provinces. Here, we generate chronostratigraphic models for both datasets using the same statistical techniques and show that the two datasets agree very well. More specifically, we infer that (1) age modeling of the 40Ar/39Ar dataset results in constant eruption rates with relatively large uncertainties through the duration of the Deccan Traps eruptions and provides no support for (or evidence against) the pulses identified by the U−Pb data, (2) the stratigraphic positions of the Chicxulub impact using the 40Ar/39Ar and U−Pb datasets do not agree within their uncertainties, and (3) neither dataset supports the notion of an increase in eruption rate as a result of the Chicxulub impact. We then discuss the importance of systematic uncertainties between the dating methods that challenge direct comparisons between them, and we highlight the geologic uncertainties, such as regional stratigraphic correlations, that need to be tested to ensure the accuracy of eruption models. While the production of precise and accurate geochronologic data is of course essential to studies of Earth history, our analysis underscores that the accuracy of a final result is also critically dependent on how such data are interpreted and presented to the broader community of geoscientists.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An evaluation of Deccan Traps eruption rates using geochronologic data

et al. 2021

View full text Add to dashboard Cite

show abstract

“…1), consistent with assertions that other foraminifera (O. universa) fractionate Ca isotopes similarly to inorganic calcite 29 . Moreover, four geologic δ 44/40 Ca records representing multiple candidate OA events and different marine carbonate archives, including foraminifera, mollusks, and bulk sediments, all show positive excursions consistent with reduced precipitation rates [30][31][32][33] .…”

mentioning

confidence: 89%

Calcium isotope ratios of malformed foraminifera reveal biocalcification stress preceded Oceanic Anoxic Event 2

Kitch

Jacobson

Sageman

et al. 2022

Commun Earth Environ

Self Cite

View full text Add to dashboard Cite

Ocean acidification causes biocalcification stress. The calcium isotope composition of carbonate producers can archive such stress because calcium isotope fractionation is sensitive to precipitation rate. Here, we synthesize morphometric observations of planktic foraminifera with multi-archive calcium isotope records from Gubbio, Italy and the Western Interior Seaway spanning Cretaceous Ocean Anoxic Event 2 (~94 million years ago). Calcium isotope ratios increase ~60 thousand years prior to the event. The increase coincides with foraminiferal abnormalities and correlates with existing proxy records for carbon dioxide release during large igneous province volcanism. The results highlight Ocean Anoxic Event 2 as a geologic ocean acidification analog. Moreover, decreasing calcium isotope ratios during the event provide evidence for ocean alkalinization, which could have shifted air-sea carbon dioxide partitioning. These data offer an explanation for the Plenus Cold Event and further have implications for refining ocean alkalinity enhancement, a leading anthropogenic carbon dioxide removal strategy.

show abstract

“…Sprain et al (2019) plot the 40 Ar/ 39 Ar dataset in a way that gives the impression that there was an increase in eruption rate associated with the Chicxulub impact. Indeed, it seems that authors of subsequent papers (Henehan et al, 2019;Hull et al, 2020;Linzmeier et al, 2020;Milligan et al, 2019;Montanari and Coccioni, 2019), in addition to the associated News and Views piece in the same issue of Science 90 (Burgess, 2019) and subsequent discussion and news coverage on Sciencemag.org (Kerr and Ward, 2019;Voosen, 2019), seem to conclude that the datasets do not agree on the eruption rates of the Deccan Traps.…”

mentioning

confidence: 99%

“…We have highlighted here several issues with the way the 40 Ar/ 39 Ar data were used to build a model for eruption rates of the Deccan Traps, and do so because the model has been reproduced in summaries of the two articles (Burgess, 2019), the popular media (e.g., Voosen, 2019), and in subsequent presentations and papers discussing these datasets (Henehan et al, 330 2019;Hull et al, 2020;Linzmeier et al, 2020;Milligan et al, 2019;Montanari and Coccioni, 2019). The potential fallout of these misunderstandings is that it risks painting a picture among non-geochronologists that the U-Pb and 40 Ar/ 39 Ar methods cannot agree on the eruption history of the Deccan Traps and that the geological community should be skeptical of geochronology in general.…”

mentioning

confidence: 99%

An evaluation of Deccan Traps eruption rates using geochronologic data

Schoene

Eddy

Keller

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract. Recent attempts to establish the eruptive history of the Deccan Traps large igneous province have used both U-Pb (Schoene et al., 2019) and 40Ar/39Ar (Sprain et al., 2019) geochronology. Both of these studies report dates with high precision and unprecedented coverage for a large igneous province, and agree that the main phase of eruptions began near the C30n-C29r magnetic reversal and waned shortly after the C29r-C29n reversal, totaling ~700-800 ka duration. Nevertheless, the eruption rates interpreted by the authors of each publication differ significantly. The U-Pb dataset was interpreted to indicate four major eruptive pulses, while the 40Ar/39Ar dataset was used to argue for an increase in eruption rates coincident with the Chicxulub impact (Renne et al., 2015; Richards et al., 2015). Although the overall agreement in duration is an achievement for geochronology, the disparate eruption models may act to undermine this achievement in the eyes of the broader geologic community. Here, we generate chronostratigraphic models for both datasets using the same statistical techniques and conclude that 1) age modeling of the 40Ar/39Ar dataset results in constant eruption rates with relatively large uncertainties through the duration of the Deccan Traps, and cannot verify or disprove the pulses identified by the U-Pb data, 2) the stratigraphic position of the Chicxulub impact within the 40Ar/39Ar dataset is much more uncertain than was presented in Sprain et al. (2019), and 3) neither dataset supports an increase in eruption rate as a result of the Chicxulub impact. While the production of precise and accurate geochronologic data is of course essential to studies of Earth History, our analysis underscores that the accuracy of a final result also is critically dependent on how such data are interpreted and presented to the broader community of geoscientists.

show abstract

Calcium isotope evidence for environmental variability before and across the Cretaceous-Paleogene mass extinction

Cited by 17 publications

References 52 publications

An evaluation of Deccan Traps eruption rates using geochronologic data

An evaluation of Deccan Traps eruption rates using geochronologic data

Calcium isotope ratios of malformed foraminifera reveal biocalcification stress preceded Oceanic Anoxic Event 2

An evaluation of Deccan Traps eruption rates using geochronologic data

Contact Info

Product

Resources

About