1 23 Facies International Journal of Paleontology, Sedimentology and Geology ISSN 0172-9179 Volume 59 Number 1 Facies (2013) 59:7-18 DOI 10.1007/s10347-012-0330-4 Microbialite formation in southern Sinai (Egypt) Daniela Basso, Valentina Alice Bracchi & Andrea Noemi Favalli