Identification of calcified coccoid cyanobacteria forming stromatoporoid stromatolites

Abstract
A simple technique is described enabling the identification in scanning electron micrographs of combined fractured and etched stromatoporoid sections, the cyanobacteria-like coccoid aggregates building the entire stromatoporoid structure. The coccoid aggregates from stromatoporoids [Silurian age] are closely related to extant calcified coccoid cyanobacteria (Pleurocapsales) forming stromatolitic mats in Laguna Mormona (Baja, California [Mexico]) and Sabkha Gavish (Sinai [Egypt]).