FIG. 15 in The Sarmatian (middle Miocene) "petrified forest" of Gramada (NW Bulgaria): role of the calcareous crusts

FIG. 15. — GR5 dome-shaped top microfacies; A, B, general views showing dense micritic crusts; C, detail of micritic columns; D, partially peloidal micritic crust with poorly expressed filamentous structures; E, composite micritic crust with very degraded corallinaceous crusts and fine filamentous structures (arrow); F, G, corallinaceous crusts (type 2) showing fairly well-preserved cell structures; H, probable corallinaceous crust; I, accumulations of peloids often oolitized and bioclasts with undetermined honeycomb structures (see Fig. 10G). Scale bars: A, B, 5 mm; C, D, 500 µm; E, 200 µm; F-I, 100 µm.