7-2 Reexamining the northern Flinders Uratanna Formation sediments to constrain the early evolution of animals

Session: Undergraduate Research, Part I (Posters)

Poster Booth No.: 2

Presenting Author:

Jasette Flanigan

Authors:

Parker, Diana Brooke ¹, Flanigan, Jasette Elise², Darroch, Simon A.F.³, Racicot , Rachel A.⁴, Gibson, Brandt M.⁵, Hull, Kevin⁶

(1) Geology, University of Tennessee at Martin, Martin, Tennessee, USA, (2) Geology, University of Tennessee at Martin, Martin, TN, USA, (3) Paleozoology, Senckenberg Museum of Natural History, Frankfurt, Hesse, Germany, (4) Messel Research, Senckenberg Museum of Natural History, Frankfurt, Hesse, Germany, (5) Geology, University of Tennessee at Martin, Martin, TN, USA, (6) University of Adelaide, Adelaide, South Australia, Australia,

Abstract:

Terminal Ediacaran to early Cambrian sediments record the early evolution of animals, as well as a critical step-change in the diversity - and intensity - of ecosystem engineering processes. The trace fossil record during this interval provides excellent documentation of this escalation. South Australia’s Flinders Ranges expose rare outcrops of Uratanna Formation sediments that are thought to be basal Cambrian. These deposits are one of the few places in the world that preserve putative 'survivors' of the iconic Ediacaran fauna following enigmatic biotic turnover events in the latest Neoproterozoic. In this project, we explore little-studied outcrops around Castle Rock and Mt. Telford areas of the northern Flinders that expose siliciclastic sediments belonging the Uratanna through Parachilna Formations that unconformably overlie the Ediacaran-aged Rawnsley Quartzite. We present new log sections through these sediments that characterize the lithology, bedding, sedimentary structures, and ichnotaxa distribution through this interval. In ongoing work, we hope to reconstruct the ecosystem engineering impacts associated with these traces and use these to test hypotheses for the drivers of Ediacaran extinction and explosive radiation of animals that followed.

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