Cretaceous Orbitolinidae (Foraminifera) from Onshore and Offshore South-West England

M D Simmons,C L Williams

doi:10.1144/jm.11.1.21

Abstract

Abstract. The occurrence of orbitolinids in onshore and offshore South-West England is fully documented for the first time. Palorbitolina lenticularis is known from the Early Aptian — Late Barremian sediments of the offshore Fastnet Basin, and may also occur in the Aptian Farringdon Greensand. Late Albian Orbitolina sefini occurs in the Wolborough Limestone of Devon, whilst at Haldon, Devon, the orbitoline faunas are of Early Cenomanian age and referable to Orbitolina cf. concava. The orbitolinids from the Upper Greensand of the south-east Devon coast and the Fastnet Basin cannot be precisely identified, but belong to the Late Albian — Early Cenomanian O. sefini - O. concava plexus. Previous records of Orbitolina from the Upper Greensand at Wilmington are shown to be mistaken. These records are in fact referable to the sponge Porosphaera. The precise identification of some of the orbitolinids from South-West England supports the ages of the Wolborough Limestone and Haldon Sands suggested by Hamblin &amp; Wood (1976). It is thought that orbitolinids migrated from Iberia to South-West England via the South-West Approaches during the Late Albian.

Highlights

TheOrbitolinidae are a familyof complexagglutinating larger Foraminifera,typical of the Tethyan Realm. known fromJurassicand Palaeogene sediments, they aremost typical of, and were most diverse, during Early and mid-Cretaceous times
We have studied material from the mid-Cretaceous sediments of the Fastnet Basin
Orbitolinids are common at a stratigraphically higher level than at Wolborough in the Upper Greensand and Cenomanian Limestone equivalents of the Haldon Hills.These occurrences are in the Cullum Sandswith Chert

Summary

Introduction

TheOrbitolinidae are a familyof complexagglutinating larger Foraminifera,typical of the Tethyan Realm. known fromJurassicand Palaeogene sediments, they aremost typical of, and were most diverse, during Early and mid-Cretaceous times. Hart and his colleagues recorded Orbitolina from Wolborough, the Haldon Hills, the south-east Devon coast and Warminster.

Results

Conclusion