Abstract Diplocraterion luniforme occurs abundantly in the Cretaceous Hasandong Formation of the Jinju area, Korea. The Hasandong Formation consists of fluvial deposits mainly composed of sandstone, siltstone, mudstone and shale. The formation contains freshwater bivalves such as Trigonioides sp. and Plicatounio sp., fossil tree stumps, carbonized wood, stromatolites, caliche nodules, current ripples and desiccation cracks. The trace fossils Planolites ichnosp., Skolithos ichnosp. and Taenid‐ium ichnosp. are also commonly observed. Diplocraterion luniforme occurs in the gray shale which is considered to have been deposited in floodplain lake environments. This report represents an unusual record of a nonmarine occurrence of Diplocraterion, which has previously been generally regarded as a diagnostic marine trace fossil. Key words: Diplocraterion luniforme nonmarineHasandong FormationKoreaCretaceous Notes Corresponding author.
Numerous and diverse forms of Lockeia are excellently preserved in the dolomitic mudstone of the Middle Ordovician Yeongheung Formation, Yeongweol, Korea. They allow a description of L. siliquaria, L. amygdaloides, L. ichnosp. and L. triangulichnus nov. ichnosp. L. siliquaria is a thin, seed‐like form, tapered at both ends. L. amygdaloides is a relatively plump, almond‐shaped form, tapered at one end while the other end is obtusely pointed or somewhat rounded. L. triangulichnus is a small triangular trace with three ridges from apex, resembling a pyramid, preserved in convex hypo‐relief and concave epirelief. L. ichnosp. is a pear‐shaped or irregular form. Usually, populations of Lockeia are monospecific and this occurrence is unique. Since all four ichnospecies of Lockeia are found on a single bedding plane of the Yeongheung Formation, the criteria used for ichnospecific differentiation appear valid.
Shell beds containing characteristic trace fossils of the Early Pleistocene Seogwipo Formation represent a storm‐influenced succession. They generally consist of: (1) initial firmground substrates in foreshore to offshore environments as indicated by the Glossifungites ichnofacies, including Gastrochaenolites and Thalassi‐noides, (2) basal storm‐erosive lag deposits, (3) reworked shell beds of main storm deposits, (4) massive sandstone of waning storm deposits containing Skolithos, and (5) bioturbated sandstones of post‐storm offshore deposits indicated by the Cruziana ichnofacies that include Chondrites, Helminthopsis, Laminites, Phy‐codes and Thalassinoides. This succession of shell beds reflects a gradational decrease in hydraulic energy levels induced by storms. Trace fossils including Gastrochaenolites lapidicus, Helminthopsis ichnosp., Laminites ichnosp. Thalassinoides cf. paradoxica and T. cf. suevicus are systematically described from shell beds of the Seogwipo Formation.
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