Lyell Collection
Journal of the Geological Society
Lyell Centre  |   Lyell Collection  |   Subscriptions   |   Geological Society  |   Email alerts  |   Online bookshop  |   Help

Keywords:
Author:
Advanced search>>
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (23)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Grimes, S. T.
Right arrow Articles by Parkes, R. J.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation
Journal of the Geological Society; 2002; v. 159; issue.5; p. 493-501;
DOI: 10.1144/0016-764901-176
© 2002 Geological Society of London

Original Article

Fossil plants from the Eocene London Clay: the use of pyrite textures to determine the mechanism of pyritization

Stephen T. Grimes1,2, Kevin L. Davies1, Ian B. Butler1, Fiona Brock3, Dianne Edwards1, David Rickard1, Derek E. G. Briggs3 & R. John Parkes3

1 1Department of Earth Sciences, Cardiff University, PO Box 914, Park Place, Cardiff CF10 3YE, UK (e-mail: EdwardsD2@Cardiff.ac.uk)
2 2Present address: Department of Geology, Royal Holloway University of London, Egham TW20 OEX, UK
3 3Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK

Pyritized twigs and roots from the Eocene London Clay of SE England were studied to gain a better understanding of the process of pyritization by investigating pyrite textures in relation to cell type and quality of preservation. Highly polished sections and fractured surfaces taken from 124 specimens were examined using optical microscope and SEM, the latter equipped to map pyrite and carbon. Pyrite textures include microcrystalline, framboidal, massive polycrystalline, and subhedral or euhedral forms. The highest fidelity of preservation is always associated with microcrystalline pyrite precipitation on wall surfaces with subsequent infilling of cells with framboids or polyhedra preventing compression during burial but contributing nothing to actual ultrastructural preservation. Ultrastructurally, parenchymatous cell walls are coalified, whereas microcrystalline pyrite plus coalified material were observed within lignified cell walls. In all, four stages of pyritization are documented. Observations are interpreted in the light of recent experiments on pyritization of living material and the chemistry of pyrite formation in anoxic environments involving an aqueous, and hence mobile, FeS cluster complex as a precursor. The complexity of the fossilization process is reflected in the presence of different textures in adjacent cells of the same tissue. This demonstrates the development of isolated chemical microenvironments as pH and Eh vary in response to decay, and mineralization and pyrite overgrowths within a cell indicate local microenvironmental changes through time.


Keywords: London Clay, pyrite, plants, preservation.




This article has been cited by other articles:


Home page
 Am. J. Bot.Home page
M. L. DeVore, P. Kenrick, K. B. Pigg, and R. A. Ketcham
Utility of high resolution x-ray computed tomography (HRXCT) for paleobotanical studies: an example using London Clay fruits and seeds
Am. J. Botany, 2006; 93: 1848 - 1851.
[Abstract] [Full Text] [PDF]

Home page
 PALAIOSHome page
F. BROCK, R. J. PARKES, and D. E.G. BRIGGS
EXPERIMENTAL PYRITE FORMATION ASSOCIATED WITH DECAY OF PLANT MATERIAL
Palaios, 2006; 21: 499 - 506.
[Abstract] [Full Text] [PDF]

Home page
 PALAIOSHome page
A. P. WOLFE, M. B. EDLUND, A. R. SWEET, and S. D. CREIGHTON
A First Account of Organelle Preservation in Eocene Nonmarine Diatoms: Observations and Paleobiological Implications
Palaios, 2006; 21: 298 - 304.
[Abstract] [Full Text] [PDF]

Home page
 GeologyHome page
S. E. Gabbott, H. Xian-guang, M. J. Norry, and D. J. Siveter
Preservation of Early Cambrian animals of the Chengjiang biota
Geology, 2004; 32: 901 - 904.
[Abstract] [Full Text] [PDF]

Home page
 PALAIOSHome page
Anatomical Evidence in the Detection of the Earliest Wildfires
Palaios, 2004; 19: 113 - 128.


Home page
 Journal of the Geological SocietyHome page
A. C. Scott, A. C. Scott, and M. E. Collinson
Non-destructive multiple approaches to interpret the preservation of plant fossils: implications for calcium-rich permineralizations
Journal of the Geological Society, 2003; 160: 857 - 862.
[Abstract] [Full Text] [PDF]