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Plate XIX. Devonian Backreef Organisms

(A) Backreef calcisphere wackestone, facies 12D, Chapter IV. The radiosphaerids
are probably the fruiting cases of algae, perhaps dasycladaceans, which thrived in
the quiet, shallow waters of lagoons commonly in interiors of carbonate banks.
Note the grumelous, vaguely pelleted matrix and small-scale fenestral fabric.
Photograph is courtesy of J. E. Klovan, University of Calgary, Alberta, from Late
Devonian beds of western Canada. Thin section, x 65

(B) Tubular stromatoporoid, Amphipora, in micrite from Devonian of Alber-
ta, Canada; facies ltD, Chapter IV. Southesk Formation, Burnt Timber Creek,
northwest of Calgary. Photograph is courtesy of A.J. Wells and Koninklijke Shell
Exploration and Production Laboratory, The Netherlands. Polished slab, x 21/4
(C) Cross section of Amphipora in micrite from Alberta basin. Photograph is
courtesy of J. E. Klovan, University of Calgary, Alberta, Canada. Thin section,
x 25. Specimen about 4.0 mm across