Heterolithic bedding

Sedimentary structure made up of interbedded deposits of sand and mud

Heterolithic bedding is a sedimentary structure made up of interbedded deposits of sand and mud. It is formed mainly in tidal flats but can also be formed in glacial environments. Examples from fluvial environments have been documented but are rare. Heterolithic bedding forms in response to alternations in sediment supply and tidal velocity. The fluctuations result in the interbedded layers of sand and mud. The rippled sand layer is formed during high tidal currents, while the mud is deposited during slack tide periods.

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