The following was posted on SEDNET, maybe
someone here can answer his question
From: Roger Suthren
[mailto:rjsuthren@yahoo.co.uk]
Sent: Friday, October 22, 2004
9:55 AM
To: sednet@yahoogroups.com
Subject: [sednet] Periphyton and
oncolites
A few years ago on one of the trails in Everglades
NP, I saw for the
first time apparently spongy accumulations of
carbonate around live
plants in slowly flowing water, described on the
interpretative
signs as periphyton. I wondered if there is any
relationship between
this material and some of the oncolites I am
familiar with from the
late Cretaceous and early Tertiary continental
sequences of southern
France. Many of these oncolites are cylindrical, apparently formed
around hollow reeds or other types of plant stems
now represented by
spar-filled tubes (and others around nonmarine
bivalves and
gastropods). They were described in the 1970s and
1980s by Plaziat
and Freytet.
Has anyone on the list studied periphyton? Does it
have a concentric
structure, or any of the other features of
oncolites? I wonder if
some of the French oncolites might have been
growing around trailing
live plants rather than the more traditional
'rolling' model for
oncolites. Or is periphyton something quite
different?
Thanks,
Roger Suthren
______________________________________
Fabian
Duque-Botero, PhD. Candidate
Florida International
University
Department of Earth Sciences
University Park
Campus, PC 344
11200 SW 8th Street
Miami, Fl. 33199
fabian.duque-botero@fiu.edu
http://www.fiu.edu/~fduqu002
Tel: (305) 348-3147
Fax: (305) 348-3877