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Carbonate cementation in the Triassic Otter Sandstone of Budleigh Salterton, SW England, occurs in two distinct forms: large, vertical, concentrically zoned cyclinders, and thin subhorizontal sheets. The former represent rhizocretions of the tap roots of phreatophytic plants which colonized bars and abandoned channels on a large braidplain. The sheets represent cementation around ancient water‐tables. The precipitation of the rhizocretions took place, at least in part, during the life of the plants and δ13C and δ18O values support the view that evapo‐transpiration induced carbonate precipitation. Palaeosol profiles are rare in the Otter Sandstone, reflecting the geomorphological instability of the braidplain surfaces. In contrast, rhizocretionary and sheet calcretes, which formed several metres below the active depositional surface, are abundant because they had a high preservation potential.

Arcuate mud‐drapes have been observed in an interdune area in southern Tunisia. They are believed to have been formed by deposition from ponded water around aeolian dunes during flood events. They are preferentially preserved on the stoss‐side of the dunes as a result of subsequent dune migration, and exhibit extensive evidence of animal tracks. They are useful in illustrating dune‐interdune dynamics and recording the type of animals present.

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