Departmental Papers (EES)
Document Type
Journal Article
Date of this Version
June 2004
Abstract
The ultrastructural examination by transmission electron microscopy of 45-million-year-old mummified leaves of Metasequoia extracted from the Upper Coal member of the Buchanan Lake Formation in Napartulik on Axel Heiberg Island revealed the preservation of intact chloroplasts and chloroplast components. Abundant tanniferous cell inclusions may indicate that the 3-mo period of constant daylight during the Arctic summer induced high concentrations of tannins in the leaf tissues, which may have arrested microbial degradation of the litter. Quantified differences in the extent of chloroplast preservation through a vertical section of the lignite suggest that short-term shifts in the depositional environment took place, perhaps influencing the exposure of the leaf tissues to conditions that would either promote or inhibit decomposition.
Keywords
Buchanan Lake Formation, chloroplast, Eocene, fossil, lignite, Metasequoia, mummification, thylakoid
Date Posted: 07 December 2005
This document has been peer reviewed.
Comments
Reprinted from American Journal of Botany, Volume 91, Number 6, June 2004, pages 816-824.