Fig. 7

Microfacies of stratigraphic units U1–U4. a Sample FAb 444 (cross-polarized light), Unit 1, Section 1. Biocalcarenitic floatstone matrix. Note dissolved cortoids (co; i.e. rounded skeletal grains covered by a thin micritic envelope; Flügel 2004) and late gypsum cement (gc) filling both primary and secondary porosities. b Sample FAb 43 (plane-polarized light), Unit 2, Section 2. Bioclastic rudstone/framestone. Note large coral fragment (po = Porites sp.) encrusted by benthic foraminifer (ef), numerous dissolved cortoids in the rudstone/framestone matrix, and rare sparry cement. c Sample FAb 170 (plane-polarized light), Unit 3, Section 1. Well-cemented grainstone. Note the occurrence of micro-oncoid (mo), and of a first generation of fibrous rim cement (arrow) indicating an early phase of marine diagenesis. d Sample FAb 171 (plane-polarized light), Unit 4, Section 1. Well-sorted, skeletal calcarenite. This portion of thin-section has been stained with Feigl’s solution. The black stain on the Halimeda fragment (ha) reveals it has retained its original aragonite mineralogy. Note pedogenic micrite in primary porosity