We provide the first reports of some rare trace fossils from the middle Turonian (Upper Cretaceous) of the Sudety Mountains (SW Poland, Upper Nysa Kłodzka Graben, Długopole Górne Quarry). These include burrows ?Ancorichnus isp., Asterosoma cf. ludwigae Schlirf, 2000, Asterosoma isp., cf. Phycodes isp., Dactyloidites ottoi (Geinitz, 1849), Funalichnus strangulatus (Fritsch, 1883), Phycodes cf. palmatus (Hall, 1852), cf. Phycodes isp., Phycosiphon incertum Fischer-Ooster, 1858, ?Phycosiphon isp., Planolites beverleyensis (Billings, 1862) and borings Entobia isp. Some body fossils, bivalves ?Brachidontes sp., Lima canalifera Goldfuss, 1836, Pinna (Pinna) cretacea (Schlotheim, 1813) and Rhynchostreon suborbiculatum (Lamarck, 1801) are also reported. The trace fossil assemblage indicates a distal Skolithos ichnofacies and proximal Cruziana ichnofacies, which characterize a proximal and distal lower shoreface setting respectively. Sedimentation of the middle Turonian sandstones took place in a shallow epicontinental sea of normal salinity and a soft substrate, which was well-oxygenated under low-moderate hydrodynamic conditions. The presence of the oyster Rhynchostreon in the deposits studied suggests the influence of a warm Tethys Ocean.
In the sandstones and conglomerates of the Idzików Conglomerate Member (Coniacian), exposed in the Idzików Quarry (SW Poland, Upper Nysa Kłodzka Graben), a moderately diverse assemblage of trace fossils has been recognized. The trace fossils include Arenicolites isp., Asterosoma isp., ?Bergaueria isp., Cylindrichnus isp., Conichnus conicus, Curvolithus simplex, Dactyloidites ottoi, Diplocraterion parallelum, ?Diplocraterion isp., Gyrochorte isp., Gyrophyllites aff. kwassizensis, Macaronichnus segregatis, Ophiomorpha nodosa, Ophiomorpha isp., ?Palaeophycus isp., ?Rhizocorallium isp., Rosselia isp., ?Scolicia isp., Teichichnus isp. and Thalassinoides isp. Escape traces (fugichnia) and some unidentified trace fossils also were found. The following ichnoassociations are distinguished: (IA1) Ophiomorpha-Cylindrichnus, (IA2) Asterosoma-Conichnus and (IA3) Ophiomorpha- Arenicolites. IA1 probably represents a mixture of the impoverished proximal Cruziana ichnofacies and the distal Skolithos ichnofacies, which points to the lower, weakly storm-affected shoreface. IA2 is interpreted as the archetypal Skolithos ichnofacies (opportunistic colonization of tempestite beds) with some elements of the Cruziana ichnofacies (bioturbated, fair-weather background deposits) in the middle, moderately storm-affected shoreface. IA3 is assigned to the archetypal Skolithos ichnofacies, which indicates the upper shoreface-foreshore settings. The trace-fossil evidence implies that the Upper Cretaceous succession was deposited in a shallow, open basin with good oxygenation of the sea floor and normal salinity, under low- to moderately high-energy hydrodynamic conditions. On the basis of ichnological and sedimentological analyses, the deposits studied originated in a system of fan-delta and shallow-shelf settings with common transitional-proximal tempestites. They were deposited in the eastern part of the Upper Nysa Kłodzka Graben during the Coniacian regression.
The ammonites Lewesiceras peramplum Mantell and ?Lewesiceras sp. are reported from the Upper Cretaceous in the Nysa Kłodzka Graben; they date from the Middle Turonian and ?Coniacian, respectively. The Middle Turonian limestones of the Stara Bystrzyca quarry contain an abundant assemblage of inoceramids (Inoceramus cuvieri Sowerby and I. lamarcki Parkinson) and other bivalves, including oysters, as well as brachiopods and trace fossils. Micropalaeontological data show the presence of foraminifers and siliceous sponge spiculae, bryozoans, ostracods and fragments of bivalves and gastropods. The Middle Turonian calcareous deposits belongs to the upper part of the Inoceramus lamarcki Zone (late Middle Turonian) and were deposited on a shallow, subtidal offshore shelf. They overlie the Middle Turonian Bystrzyca and Długopole Sandstones, which represent foreshore-shoreface delta deposits. The fossil assemblage suggests a moderate- to low-energy, normal-salinity environment with occasionally an oxygen deficit.
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