Struktury biogeniczne w osadach retu i dolnego wapienia muszlowego Gór Świętokrzyskich

Abstract

 Opisano struktury biogeniczne (ślady działalności organizmów, skałotocza, koprolity i tropy kręgowców) napotkane w osadach retu i wapienia muszlowego Gór Świętokrzyskich. Występują one w wapieniach, marglach i piaskowcach i są związane z płytkimi strefami morza oraz z obszarami nadbrzeżnymi plażami, bagnami i deltami.

BIOGENIC STRUCTURES IN RHOT AND MUSCHELKALK ROCKS IN THE GÓRY ŚWIĘTOKRZYSKIE MTS

Biogenic structures found in Rhot and Lower Muschelkalk rocks at the margin of the Góry Świętokrzyskie Mts (Fig. 1) are discussed. They include traces of browsing in deposits and other life activities: borings, coprolites and trails. Of these, Cylindricum, Planolites, Rhizocorallium, Balanoglossites, Trypanites and Chirotherium trails are known from Triassic rocks in western Europe. Some other traces resemble those known from other regions whereas the remaining ones seem to be unknown beyond the area of the Góry Świętokrzyskie Mts. Trace A resembles Paraophidichnium triassicum Demathieu, D – Imbrichnus Hallam, and some traces of crawling – Palaeophycus Hall. Some of trails may belong to Rotodactylus Praebody (Table IV, Figs. 8, 9) and siliceous coprolites look similar to Coprulus Allasinaz.

The knowledge of sedimentary environments in the Rhot and Muschelkalk basins in the Góry

Świętokrzyskie Mts makes admissible the presumption of origin of Cylindricum and Problematicum traces in zones of tidal flat and deltas. Crawling traces A, B, C, and those of worms and molluscans, Palaeophycus? structures and Planolites channels originated at sandy floor or beach of a shallow reservoir. Trails of vertebrates were similarly made in sandy beach zone.

The traces D, E, H, G and Rhizocorallium originated in shallow sublittoral environment of sedimentation of calcareous muds. The development of Enterdpneusta and Balanoglossites was connected with seasonal breaks in sedimentation. Trypanites traces were beginning to appear along with hardening of basin floor sediments. Traces of crawling F and borings I were presumably originating in cocquinas accumulating in beach zone. Coprolite? K, coprolite L and Coprulus? Allasinaz apear related to shallow-water low-energy environment.