Geological Disposal of Carbon Dioxide


Official GEODISC web site here

Program Manager: Mr Andy Rigg (APCRC)
NCPGG Coordinator: Assoc Prof Simon Lang
NCPGG Project Leaders: Assoc Prof Simon Lang (Project 2),
Prof Richard Hillis (Project 4), Dr Nick Lemon (Project 1O)


Program Overview:
Liquefied natural gas projects with a total value of around $20 billion are planned for Australia over the next decade. Together, they will generate an increase of approximately 3% in Australia's GDP and in excess of 50,000 jobs. One of the major risks to this vast investment is the lack of an agreed strategy to deal with the major increase in CO2 emissions that will result from these developments. The recent Kyoto Protocol has served to focus even more attention on this issue. This proposal addresses the issue through leading edge cooperative research.

The answer to sustaining Australia's economic development whilst at the same time meeting emission targets lies in developing suitable methodologies for CO2 sequestration. One of the key sequestration options is geological disposal. The method, which involves injection of supercritical CO2 into the deep subsurface is being tested on a commercial scale in only one place in the world, although several other countries are now developing research programs into the technique. This proposal for research into the Geological Disposal of CO2 (GEODISC) will for the first time investigate the applicability of the method to Australia to enable it to dispose of large volumes of CO2. It is expected that several sites (at least four) will be selected around Australia to study CO2 sequestration potential.

The NCPGG is involved in three project areas for GEODISC. Project 2 (Site specific studies), Project 4 (Geomechanics and petrophysics) and Project 10 (Geological analogues). Projects are detailed below.


PROJECTS


Project 2: Site Specific Studies for Geological Disposal of CO2
Project leader: Assoc Prof Simon Lang

This project involves detailed sedimentological and stratigraphic analysis of at least four potential carbon dioxide sequence sequestration sites around Australia. In addition, hydrogeological analysis of these sites will be conducted by co-workers at CSIRO Land and Water in Perth. The project will be conducted by an interdisciplinary team of PhD students and research fellows under the supervision and direction of academic staff at the NCPGG. Each site involves analyses of company reports, seismic data, wireline logs, cores, thin sections, pressure data, water analyses, MICP analyses, and the output is focussed on the development of a 3D geological model suitable for transfer to a reservoir simulator (Projects 3 and 5). The first site to be investigated was conducted as a pilot study to form a working methodology to be used for the other sites. This pilot study, results of which were presented to the Geodisc steering committee at the end of 2000, was conducted primarily by Dr Simon Lang and Ms Catherine Gibson-Poole, with key contributions by Dr Ghazi Kraishan, Mrs Janet Skinner, Dr Jürgen Streit, Mr Adam Hill, Dr John Kaldi and Mr Tom Kivior from the NCPGG, and Dr Claus Otto and Dr Elise Bekele from CSIRO. The final pilot study report was due to be submitted in early 2001.

The study of the second site was initiated at the end of 2000 with a preliminary screening of the data from an oil and gas field. This was conducted by PhD student Jonathan Salo under the supervision of Dr Lang. Work on the third site will begin in early 2001 with the arrival of PhD student Robert Root.

PhD Project: Reservoir Characterisation and Sequence Stratigraphy, NW Australia -Opportunities for CO2 Sequestration.
PhD Student: Catherine Gibson-Poole (commenced 2000)
Supervisor: Assoc. Prof Simon Lang
Funding support: APCRC - GEODISC Program
Scholarship support: Australian Postgraduate Award and GEODISC

PhD Project: Geological Sequestration of CO2 in Sub-Surface Reservoirs.
PhD Student: Jonathan Salo (commenced 2000)
Supervisor: Assoc. Prof Simon Lang
Funding support: APCRC - GEODISC Program
Scholarship support: GEODISC


Project 4: Geomechanics and Petrophysics
Project Leader: Prof Richard Hillis (NCPGG)
Staff: Dr. Jürgen Streit and Mrs Janet Skinner

This project is (i) investigating the geomechanical effects of injection with particular reference to the propensity of CO2 injection to lead to the (re-)activation of faults and fractures and thereby leakage of C02, and; (ii) undertaking requisite petrophysical analysis of pilot study sites for reservoir simulation.

The conventional wireline log-based assessment of petrophysical properties (Rw, Sw, Vsh, lithology, porosity, permeability) required for evaluation and simulation of potential CO2 injection sites is being undertaken by Janet Skinner at the NCPGG. Project 4 also involves fundamental research on, and site-based assessment of whether CO2 injection is likely to reactivate faults. Such fault reactivation is likely to have a negative effect on the long-term sequestration of CO2. Dr. Jurgen Streit is working on this component of the project which involves assessing the in situ state of stress at potential subsurface injection sites and preexisting fault geometries and failure envelopes.


Project 10: Natural Analogs
Project Leader: Dr Nick Lemon (NCPGG)

Carbon dioxide occurs naturally trapped within a variety of reservoirs in the same way as petroleum gases. The Otway Basin in SE South Australia and western Victoria hosts several known gas accumulations with concentrations of carbon dioxide. Pure carbon dioxide is produced commercially from Caroline-1 near Mount Gambier. Natural accumulations of carbon dioxide provide an opportunity to study the effects of the gas on reservoir and seal mineralogy.. They also provide proof of the concept of underground storage of carbon dioxide and can be tested for trap integrity.

Raised levels of carbon dioxide are also known from the Cooper Basin, the Carnarvon Basin and the Sydney and Bowen Basins. Analysis of reservoir and seal rocks from these areas will provide ideas on the diagenetic features common to carbon dioxide accumulations and the range of features related to variations in reservoir specific features such as rock type, temperature and length of storage time. An initial study has been completed on the diagenetic mineralogy and water composition from an Otway Basin carbon dioxide reservoir and and adjacent methane reservoir.