Lower Carboniferous Foraminiferal Faunas of the Boring Ørslev No. 1, Island of Falster, Denmark

Olaf Michelsen

doi:10.34194/raekke2.v98.6889

Abstract

Lower Carboniferous foraminifera from a 1700' thick series of limestone, marlstone, and claystone in the boring Ørslev No. 1 are studied.48 forms are described. 17 of these are identified to species, two of which are established as new species and two as new subspecies, namely Lituotubella glomospiroides minima n. subsp., Septabrunsiina spissusvoluta n. sp., Endothyra danica n. sp., and E. michoti spinata n. subsp. The remaining 31 forms are given with open nomenclature; nine of these are morphospecies, provisionally referred to already known species. The study and description of the foraminifera are based on the external morphology of the tests and on defined sections of the tests.On the basis of the biostratigraphy, the deposits are referred to the Lower and Middle (?) Visean. The interval 6740'-6945', which has a fauna dominated by the family Ozawainellidae, may probably be correlated with certain parts of the Russian and the Belgian Middle Visean (Visean 2), while the interval 6945'-8440' correlates with the Lower Visean in Belgium (Visean 1) on the basis of its faunas, characterized by the genus Endothyra.

Highlights

The boring 0rslev No 1, D.G.U. file No 238 .502, is situated in the island of Falster at the coordinates 54 °46'55" N and 11 °59'02" E of Greenwich and has been made in the period of November 1967 to January 1968
Except for the first-mentioned of these, they are defined on the b
Endothyra recta is in the U.S.S.R. known only from deposits referred to Upper Tournaisian and Lower Visean, while E. convexa regularis is an important form in Middle Visean. Such species as Earlandia elegans, Brunsiina pseudopulchra, B. spirillinoides, Palaeospiroplectammina diversa, P. venusta, and Septatournayella pseudocamerata are all known from Upper Tournaisian and Lower Visean

Summary

INTRODUCTION

The boring 0rslev No 1, D.G.U. file No 238 .502, is situated in the island of Falster at the coordinates 54 °46'55" N and 11 °59'02" E of Greenwich (see text-figs. 1 and 2) and has been made in the period of November 1967 to January 1968. 7280'-7510': Limestone (dolomitic) and marlstone, grey to dark grey, alternating with sandstone, grey to light grey, very calcareous. The middle section, 6930'- 7650', is a rapidly alternating series of limestone, marlstone, claystone, and sandstone. Grey to dark grey marlstone is the dominating lithologic type in the interval 6930'-7250'; below 7100', it alternates with light grey and reddish-grey sandstone. In addition to the conditions indicated by these sandstones and the marine limestones and marlstones, the dark grey claystone with plant fossils from the interval 7260' - 7270' suggests the occurrence of a third type of conditions of deposition. BRUUN CHRISTENSEN'S description of core No 2 is given (cf CHRISTENSEN, 1971) : Core No 2, 7686'- 7746': 7686'-7720': Claystone and shale, greyish-black and dark grey, very calcareous. Solution in a 10 % HCl takes place slowly, often even if under heating

MATERIALS AND METHODS

Introduction

Conclusion

SEAN 2

Findings