Depositional Environments and Palaeogeography of the Neoproterozoic to Cambrian in the Flinders Ranges

Summary of potential research projects

The Flinders Ranges in South Australia present excellent surface exposures of the Neoproterozoic-Cambrian Adelaide Rift Complex, including sediments deposited in fluvial-deltaic to deep marine environments, large canyons and salt-diapir formed minibasins. These have great significance globally, as the Tonian to Cryogenian succession hosts key sections demonstrating extreme climatic variations through this time, whereas the upper part of the Ediacaran succession hosts exceptional palaeontological evidence for the evolution of multi-cellular life, thus representing a key time in Earth history. In addition, the sedimentary record of the Flinders Ranges has great potential for use as an analogue for similar successions in the subsurface, including hydrocarbon systems in some of the world’s most productive regions, for which there are few outcrop analogues that are as well exposed as they are here.

The rift complex formed as Rodinia split apart, yet the timing and tectonic geography of this are highly contentious with arguments about the identification of the conjugate eastern continent and the timing of rift-drift as the nascent Pacific Ocean developed. Broad palaeogeographic maps exist for the region, but by integrating sedimentology with modern geochronological techniques, these projects aim to document the sediment distribution systems, provenance evolution and tectono-geographic evolution of the Adelaide Rift Complex. There is a great potential for new detailed description and interpretation of these successions, many of which have not been previously studied, or not studied from a detailed sedimentologic perspective. The findings of this research will have broad impact.

Depending on the skills and interests of the successful applicants, potential project foci could include:

• What was the large-scale tectonic geography of the area in the Neoproterozoic? What was the open-ocean connection, when and where was this?

• Detailed interpretation of the depositional environments of the large canyons within the upper Ediacaran.

• Formulation of forward model concepts that describe dynamics of the mechanisms hypothesised to have driven canyon forming.

• Sedimentology of the Cambrian section, and potentially expansion of focus to explore a comparison between this and other Centralian Superbasin basins (e.g. the Officer and Amadeus). This could potentially become a basin-to-basin comparison between analogous strata. Basic correlations have been presented previously, but this has not been done from a detailed sedimentology, provenance, and geochemistry perspective.

• Relation of the middle Cambrian of the Flinders Ranges to the formation of circum-Gondwana orogenesis directly after the supercontinent amalgamated (i.e. a focus on sedimentology, provenance and age-dating).

Methods will include extensive fieldwork in the central and northern Flinders Ranges, involving basic geological field mapping techniques along with constructing detailed stratigraphic logs, in order to investigate sediment thickness, facies variations. Laboratory work will enable improved age constraints on the formations and likely involve U-Pb zircon and apatite, fission track detrital apatite and 40Ar-39Ar detrital muscovite analysis.

Up to two projects are available, with:

Principal supervisors: Dr Kathryn Amos and Prof Alan Collins

Co-Supervisors from a team of: Dr Mark Bunch, Dr Ros King and Dr Stijn Glorie

Eligibility and funding:
If interested in this project, you need to apply to Dr Kathryn Amos (kathryn.amos@adelaide.edu.au) to express interest and discuss your suitability, ASAP!

A keen interest and background in sedimentology and field geology is required. You will need to have a 1st class or Upper 2nd class Honours degree (or predicted grades if you’re doing Honours this year), or a relevant Master’s degree that contains a significant research component.

The successful candidate will then need to successfully apply for a University of Adelaide Domestic Scholarship (including the Australian Postgraduate Award and Divisional Scholarships – Australian and New Zealand Residents are eligible to apply). The deadline for this is October 31st

. You would need to commence study before 31st March 2017.

Funding is available to cover research expenses and attendance of at least one international conference.

How to apply: Contact Dr Kathryn Amos with your expression of interest. Please attach a copy of your degree transcripts if you are not a University of Adelaide student or graduate.

More information:

Dr Kathryn Amos, kathryn.amos@adelaide.edu.au

Prof. Alan Collins, alan.collins@adelaide.edu.au

Dr Mark Bunch, mark.bunch@adelaide.edu.au

Australian School of Petroleum and School of Physical Sciences, Centre for Tectonics, Resources and Exploration, The University of Adelaide, Adelaide, South Australia.

Further details on scholarships: https://www.adelaide.edu.au/graduatecentre/scholarships/research/opportunities/

Note: This is not open to international applicants as the deadline for International Postgraduate Research Scholarships for Semester 1 2017 has passed.