Mid-Cretaceous pCO2 based on stomata of the extinct conifer Pseudofrenelopsis (Cheirolepidiaceae)

Research Article| September 01, 2005 Mid-Cretaceous pCO2 based on stomata of the extinct conifer Pseudofrenelopsis (Cheirolepidiaceae) Matthew Haworth; Matthew Haworth 1Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar Stephen P. Hesselbo; Stephen P. Hesselbo 1Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar Jennifer C. McElwain; Jennifer C. McElwain 2The Field Museum, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA Search for other works by this author on: GSW Google Scholar Stuart A. Robinson; Stuart A. Robinson 3Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar James W. Brunt James W. Brunt 3Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar Geology (2005) 33 (9): 749–752. https://doi.org/10.1130/G21736.1 Article history received: 22 Mar 2005 rev-recd: 26 May 2005 accepted: 29 May 2005 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Matthew Haworth, Stephen P. Hesselbo, Jennifer C. McElwain, Stuart A. Robinson, James W. Brunt; Mid-Cretaceous pCO2 based on stomata of the extinct conifer Pseudofrenelopsis (Cheirolepidiaceae). Geology 2005;; 33 (9): 749–752. doi: https://doi.org/10.1130/G21736.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Stomatal characteristics of an extinct Cretaceous conifer, Pseudofrenelopsis parceramosa (Fontaine) Watson, are used to reconstruct atmospheric carbon dioxide (pCO2) over a time previously inferred to exhibit major fluctuations in this greenhouse gas. Samples are from nonmarine to marine strata of the Wealden and Lower Greensand Groups of England and the Potomac Group of the eastern United States, of Hauterivian to Albian age (136–100 Ma). Atmospheric pCO2 is estimated from the ratios between stomatal indices of fossil cuticles and those from four modern analogs (nearest living equivalent plants). Using this approach, and two calibration methods to explore ranges, results show relatively low and only slightly varying pCO2 over the Hauterivian–Albian interval: a low of ∼560–960 ppm in the early Barremian and a high of ∼620–1200 ppm in the Albian. Data from the Barremian Wealden Group yield pCO2 values indistinguishable from a soil-carbonate–based estimate from the same beds. The new pCO2 estimates are compatible with sedimentological and oxygen-isotope evidence for relatively cool mid-Cretaceous climates. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.