Proterozoic Periglacial, Turbiditic and Deltaic Sequences of the Adelaide Coast

The objective of the one day field trip will be to view the Proterozoic Periglacial, Turbiditic and Deltaic Sequences outcropping on the Adelaide Coast. Sections exposed from Marino in the north to Ochre Head in the south demonstrate the transition from a snowball earth during the Marinoan glaciation (Cryogenian Period). The sections cover a period lasting from roughly 650 to 635 million years ago. The field trip will examine periglacial siltstones and possible varvites (Reynella Siltstone), through to deep water sandstones and dolomites (Seacliff Sandstones and Nuccaleena Dolomites) and through to delta front sequences (Brachina Group and ABC Range Quartzite, 613-597 Ma).

The section records climatic and seal level gyrations during a critical period of earth’s history when ice caps were melting, sea levels were rising and ocean waters were rapidly heating.  Controversial aspects of the section include the degree of post glacial sea level rise, methane escape features generated during ice cap melting and potential early Ediacaran Proterozoic.

Attendees will require good footwear . Walking will include negotiating some gentle slopes on tracks above the seafront and loose, potentially slippery rocks on wave cut platforms.

Program

Morning

Meet at Fryer Street Reserve at 9.00am. Park either in Kurabinna Terrace or Fryer Street. With the group take walkway northwards and then down a track to the sea front to visit outcrops of Reynella Siltstone.

Return to Fryer Street Reserve walk southwards past Hallet Cove shore platform lookout and Waterfall Creek. Descent on walkway to sea front. Inspect outcrops of Seacliff Sandstone and Nuccaleena Dolomite.

Return to Walkway. Head north. Inspect view from lookout and look at outcrops of Seacliff Sandstone

Head back on Walkway to Fryer Street Reserve.

Lunch at Fryer Street Reserve.

Afternoon

After lunch head down to Ochre Point at Moana. Park near Azure Drive. Descend to Ochre Point. View ABC deltaic sandstones, Bunyeroo Formation and possible early Ediacaran Proterozoic mega fossils (613-597Ma).

Discuss findings at Kick Back Brewery (11 Old Coach Road, Aldinga, South Australia) a 10 minute drive south of Ochre Point (https://www.kickbackbrewing.au/) .