|This bedding surface
in micritic limestones shows numerous small, concentrically layered
brown concretions. These are interpreted as ferromanganese nodules which
formed in a similar way to those found on modern deep ocean floors.
See Tucker, M E. - Ferromanganese nodules from the Devonian of the Montagne Noire (S. France) and West Germany, Geologische Rundschau (1973)
|image credit: Roger Suthren. Upper Devonian, Cabrières, Hérault, S France|
-- images of sediments and sedimentary rocks at virtual-geology.info
This page is maintained by Roger Suthren. Last updated 21 January, 2004 14:05