Trace fossils on and above the transgressive surface: substrate consistency and phosphogenesis (Lower Ordovician, St Petersburg region, Russia)
Published: Oct 2006
Pages: 415 - 422
Authors: VICTORIA B. ERSHOVA, PETER V. FEDOROV, RADEK MIKULAS
Abstract: The basal layers of the Leetse Formation (Lower Ordovician, St Petersburg region, Russia) are characterized ichnologically by: 1 — local occurrence of the ichnogenera Conichnus, Bergaueria and ?Thalassinoides at the base. These traces originated by burrowing in consolidated substrate of the underlying black, clayey Dictyonema Shale and were buried by the basal bed of the Leetse Formation; 2 — the layer with camerate burrows (Amphorichnus div. isp.), filled with phosphatic substrates, ca 15 cm above the base. Considering the position of the localities of the phosphatized burrows in the basin, we presume that burrows on tops of tectonically uplifted blocks were filled by cryptocrystalline phosphorite matter. Rapid phosphate mineralization points to conditions of shallow burial, high concentration of dissolved pore water phosphate, and suitable redox interval caused by decomposition of organic matter of burrow dweller tissues.
Keywords: Lower Ordovician, Russia, St Petersburg region, firmgrounds, platform sediments, trace fossils, phosphate
Download PDF document
Volume 57 no. 5 / October 2006
CARLOS SANZ DE GALDEANO, KHALIL EL KADIRI, JOSE FERNANDO SIMANCAS, RACHID HLILA, ANGEL CARLOS LOPEZ-GARRIDO, ABDELASSIZ EL MRIHI, AHMED CHALOUAN
Paleogeographical reconstruction of the Malaguide-Ghomaride Complex (Internal Betic-Rifian Zone) based on Carboniferous granitoid pebble provenance
YENER EYUBOGLU, OSMAN BEKTAS, AYSEL SEREN, NAFIZ MADEN, RAHSAN OZER, WOLFGANG R. JACOBY
Three-directional extensional deformation and formation of the Liassic rift basins in the Eastern Pontides (NE Turkey)
PAULINA CIFUENTES-RUIZ, PETER VRSANSKY, FRANCISCO J. VEGA, SERGIO R.S. CEVALLOS-FERRIZ, ENRIQUE GONZALEZ-SORIANO, CARLOS R. DELGADO DE JESUS
Campanian terrestrial arthropods from the Cerro del Pueblo Formation, Difunta Group in northeastern Mexico
MICHAL NEMCOK, PIOTR KRZYWIEC, MAREK WOJTASZEK, LIVIA LUDHOVA, RICHARD A. KLECKER, WILIAM J. SERCOMBE, MIKE P. COWARD†
Tertiary development of the Polish and eastern Slovak parts of the Carpathian accretionary wedge: insights from balanced cross-sections
SLAVKA ANDREJKOVICOVA, JANA MADEJOVA, ADRIANA CZIMEROVA, IGOR GALKO, REINER DOHRMANN, PETER KOMADEL
Mineralogy and chemistry of Fe-rich bentonite from the Lieskovec deposit (Central Slovakia)
PATRIK KONECNY, JAROMIR ULRYCH, PAVEL SCHOVANEK, MONIKA HURAIOVA, ZDENEK RANDA
Upper mantle xenoliths from the Pliocene Kozakov volcano (NE Bohemia): P-T-fO2 and geochemical constraints
LENKA LISA, PAVEL UHER
Provenance of Würmian loess and loess-like sediments of Moravia and Silesia (Czech Republic): a study of zircon typology and cathodoluminiscence
JAROSLAV HLAVAC
Molluscan succession from Holocene tufas in the Czech Karst (Czech Republic)
VICTORIA B. ERSHOVA, PETER V. FEDOROV, RADEK MIKULAS
Trace fossils on and above the transgressive surface: substrate consistency and phosphogenesis (Lower Ordovician, St Petersburg region, Russia)