Probable Fungal Colonization and Carbonate Diagenesis of Neoproterozoic Stromatolites from South Gabon, Western Congo Basin - Geology and Resource Potential of the Congo Basin - page 89

Fig. 5.11 Schematic figure showing a proposed two-pronged mecha-
nism, for the three-stage pit formation, which could have worked sepa-
rately or in combination. Scenario (1) involves fungal colonization of the
Neoproterozoic substrate through hyphae-stolons and rhizoids invasion
of the semi-lithified sediment surface penetrating it

(mainly Ca/Mg-oxalates) and pits formation. The pits themselves become
the target of new invasion by fungal hyphae. Scenario (2) envisages
fungal vegetative parts (e.g sporangia, sporangiophores) spreading across
the colonized substrate surface and with metabolic exudates released in
the growth environment causing substrate dissolution, biomineral precip- through grain