|Conodont alteration in Devono-Carboniferous dolomites from southern Belgium|
Helsen, S. (1995). Conodont alteration in Devono-Carboniferous dolomites from southern Belgium. Geol. Mijnbouw 74(3): 225-234
In: Geologie en Mijnbouw. Koninklijk Nederlands Geologisch Mijnbouwkundig Genootschap: The Netherlands. ISSN 0016-7746, more
Carboniferous; Devonian; Conodonta; Belgium, Ardenne [Marine Regions]; Marine
apatite precipitation; conodont colour and textural alteration;dolomitization
Conodonts from selected Frasnian and Tournaisian dolomites in southern Belgium have Colour Alteration Index (CAI) values of 3.0-4.5 or 6.0-7.0. The textural alteration of these conodonts includes various features. Most striking are the subhedral apatite crystals that surround the conodont denticles. Furthermore, fields of apatite crystals, irregular apatite envelopes and apatite pseudomorphs after calcite occur on the conodont surfaces. The higher CAIs as well as the textural alteration are probably related to dolomitization processes. Phosphates may have been supplied by decomposition of organic matter or by ascending saline fluids.