Sally Edwards

PhD student - Geo

Biography

Sally was awarded her Bachelor of Science (Honours) in Geology from the University of Adelaide in 1998. Her honours work was on Diatoms and ostracods as palaeo-environmental indicators, North Stromatolite Lake, of south-eastern South Australia. In 1999 she began an MSc at James Cook University on the Wanganui Basin of New Zealand, looking at the sequence stratigraphy and sedimentology of the Castlecliffian section drillcore. This was undertaken in collaboration with the Institute of Geological and Nuclear Sciences of New Zealand. In 2006 Sally began a PhD with the ASP.

Professional experience includes 12 months working at the South Australian Museum where she worked on the depositional environments associated with the Ediacaran Fauna fossils. Sally also worked for 18 months with the University of Adelaide based sedimentology task (Physical Processes and Modelling Task 1) on the Adelaide Coastal Waters Project. Her knowledge of sedimentology and depositional environments were used to produce a sediment budget for the Adelaide metropolitan coastline.

Sally is currently the AAPG and PESA student representative for South Australia

Sally is a member of AAPG, PESA, and SEPM

PhD research project

Techniques for reservoir characterisation for the geological storage of carbon dioxide.

Supervisors: Tobi Payenberg, Bruce Ainsworth and John Kaldi

Project Support: This study is funded by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC). Sally is a part time student who is employed part time by CO2CRC.

Project outline

Atmospheric concentrations of carbon dioxide (CO2) have risen from pre-industrial levels of 280 to 360 ppm primarily as a consequence of fossil fuel combustion for energy production (Bryant, 1997). Increasing concentrations of CO2 affect the Earth-atmosphere energy balance, enhancing the natural greenhouse effect and thereby exerting a warming influence at the Earth's surface (Bachu, 2003). Debate within Australia currently focuses on alternative energy/ renewable energy sources and nuclear energy, as the means of reducing current levels of greenhouse gases and slowing global warming and climate change. Carbon capture and storage (CCS) is one method for reducing large volumes of greenhouse gas emissions (Gibson-Poole et al., 2006). CO2 can be stored geologically by a variety of different options of which deep saline formation, depleted oil and gas fields and coal beds are the three options best suited to Australian conditions (Gibson-Poole et al., 2006). CCS is a technique that is relatively cost efficient when compared to the cost of building sufficient alternative energy plants to generate enough electricity to fuel energy demanding modern lifestyles. The main requirement before proceeding with geological storage is the assessment of suitable storage sites with capacity great enough to contain the millions of tonnes of greenhouse gases produced by, for example, a single coal-fired power station each year.

This project will evaluate several rock units within different Australian sedimentary basins for their suitability for geological storage, by examining the reservoir characteristics. The first reservoir unit examined for this study is the Betts Creek Beds and its equivalents within the Galilee Basin of central Queensland.

The Galilee Basin of central Queensland is an extensive intracratonic basin covering 234,000 km2, containing up to 2800m of Late Carboniferous to Middle Triassic strata (Jackson, 1980). The formations of interest are the Permian Betts Creek Beds and its equivalents of the Bandanna Formation and the Colinlea Sandstone. These sediments have been deposited under predominantly fluvial conditions (Jackson, 1980; Allen, 2005).

The principle uncertainties that are to be investigated include the reservoir heterogeneity across the basin so that likely injection and migration pathways can be determined. Also to be determined are the potential migration distances and likely trapping mechanisms possible along the migration pathway.

Objectives

The aims of this project are:

• Within various sedimentary basins investigate the heterogeneity of various potential reservoir formations for carbon dioxide storage
• Establish a workflow for characterising reservoir continuity away from data control under different data availabilities
• Determine seal capacity
• To examine lateral variability within the reservoir formation
• Assess the presence and effects of baffles and barriers within the reservoir on CO2 migration
• Build 3-D models to examine CO2 distribution and migration through the investigated reservoir formations