Seatown Dissected Mudstone 5 – Minute burrows of marine polychaetes (bristle worms), probably Polydora species, in shallow water-filled hollows on the surface of calcareous mudstone of the Belemnite Marl Member belonging to the Charmouth Mudstone Formation, at low tide level in Seatown, Dorset, England. The depressions follow an approximately polygonal pattern which is thought to be due to the natural fractures pattern that occurs in the exposed mudstone.
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