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Fig. 13. Cartoon showing the reconstructed steps of formation of the spongy-like stratabound dissolution pattern. Step 1 indicates intense bioturbation of a lagoonal muddy subtidal unit.
The progressive relative sea-level lowering leads, during step 2, to the formation of the stromatolitic unit. The establishment of the mixing water lens occurs during the relative sea-level
lowstand responsible for platform exposure (step 3) and the permanence of the lens within the bioturbated horizons creates the spongy-like dissolution. The subsequent filling of the
cavities, after a first episode of infiltration of the red silt, appears to be related to the re-establishment of fully-marine phreatic conditions during the subsequent flooding of the
platform (step 4).

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