Early Cambrian trace fossils from the Kanmantoo Group at Red Creek, South Australia, and their stratigraphic significance

Abstract

Two ichnospecies, Helminthoidichnites isp. and Psammichnites gigas, are described from the upper part of the Madigan Inlet Member, Carrickalinga Head Formation, Kanmantoo Group at Red Creek in the eastern Mt Lofty Ranges, South Australia. These traces occur 500 – 520 m above the base of the Carrickalinga Head Formation, i.e. 600 – 620 m above pillow lavas from the previously described volcanics at Red Creek. The presence of Psammichnites confirms that the stratigraphic succession at Red Creek has an Early Cambrian age.

Key words:

• Cambrian
• Carrickalinga Head Formation
• correlation
• Kanmantoo Group
• trace fossils
• Truro Volcanics

Acknowledgements

This work is part of a continuing research programme on the Kanmantoo Group. Over a number of years, support has been provided by the University of South Australia, the Department of Primary Industries and Resources, South Australia and the ARC Collaborative Grants Scheme. Jim Gehling (South Australian Museum) and Wolfgang Preiss (Geological Survey of South Australia) are thanked for valuable advice both at the outcrop and in the laboratory. Robert Dart (University of Adelaide) is thanked for producing Figures 1, 2 and 4. Peter Haines (Geological Survey of Western Australia) and Barry Webby (Macquarie University) provided constructive reviews of the original manuscript. Jose Javier Alvaro (University of Lille, France) and Soren Jensen (University of Extramadura, Spain) gave valuable assistance with the literature. Dennis Rice (South Australian Museum) is thanked for cataloguing the specimens described here.