Erratum to “Lamination of swamp-rivulets Rivularia haematites stromatolites in a temperate climate” [Sediment. Geol. 143 (2001) 125–147]

Etude expérimentale de la lamination des stromatolithes à Rivularia haematites en climat tempéré: édification des lamines micritiques

The lamination of Rivularia haematites stromatolites (D.C.) Agardh was studied experimentally for 7 years. Micritic laminae are found to form in three stages: biological formation of dark laminae during the wet season, microsparitic calcification of these laminae in the form of clearly individualized polycrystalline aggregates and, finally, micritization of the latter by bacterial action. These three stages develop over 2 to 3 years. The occurrence of transverse, longitudinal and circular microfibrils in the outer sheath is thought to explain the nucleation and the three-dimensional structure of the microsparitic crystals of the dark laminae and of the polycrystalline aggregates.

Lamination of swampy-rivulets Rivularia haematites stromatolites in a temperate climate

Abstract Swampy-rivulets Rivularia haematites (D.C.) Agardh stromatolites were collected from the same site on the Plateau de Langres (Chaugey, France) over a seven year period. Specimens were studied in thin sections, in culture media under varying conditions of temperature and illumination, and by scanning electron microscope (SEM) in order to investigate the processes of calcification and lamination. New SEM observations confirm the polycrystalline structure of the ‘lamellae’ reported by the authors and show that the crystals composing these lamellae are elongate and aligned in the same direction as the filaments linked by them. The lamellae were also isolated in transverse sections unde…