The geomorphology, sedimentology, and diagenesis of the tidal flats of western Andros, from Williams Island to Wide Opening, are controlled by hurricanes which transport pellet mud from a subtidal accumulation zone to the supratidal zone where diagenetic processes begin under humid, tropical weather conditions.

The directions of hurricane tracks (statistically determined) since 1871 show preferential orientations which coincide with hummock orientations. Thus, hummocks are interpreted as "trainees cycloniques," or hurricane trails.

Between these hurricane trails (hummocks), seawater and rainfall fill tidal and polyhaline (18.00 g/L to 30.0 g/L) estuaries and channels, as well as tidal and mesohaline (5.00 g/L to 18.00 g/L) basins. Below sea level and away from tidal influences, oligohaline lakes and ponds (0.00 g/L to 5.00 g/L) contain living Charophytae.

Diagenesis with lithification, cementation, or dolomitization occurs around the hurricane trails, particularly in white, thick dolomitic polygons of dry sediments. It thus appears that the very early dolomitic diagenesis in the Bahamian tidal flats can be correlated with (1) a high supratidal position resulting from hurricane action and, consequently, (2) the phreatic lenses of the tidal flats which produce oligohaline and hypersodic lakes and ponds rich in Na⁺, Ca⁺⁺, K⁺, and HCO₃^- ions. An intermediate phase could either be a transitory magnesium

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carbonate or a transitory alkali-bearing carbonate.

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