Claire Rogers

PhD student - Geo

Biography

Claire Rogers graduated with a Bachelor of Science majoring in Geophysics in 2002, from the University of Adelaide. In 2003 Claire completed her Honours degree in Petroleum Geology and Geophysics at the Australian School of Petroleum. Her project, was sponsored ExxonMobil. Claire's thesis was titled "Depth Conversion Methods for the Torsk Oilfield: Investigating the Complex Velocity Field of the Seaspray Group, Gippsland Basin". Claire Began her PhD in February 2004 on fault reactivation with respect to carbon dioxide sequestration and is sponsored by the cooperative research centre for greenhouse gas technologies. Claire is a member of PESA, ASEG and the AAPG.

PhD Research Project

Geomechanical Risking for Fault Reactivation with respect to Carbon Dioxide Sequestration, Otway Basin, Australia

Supervisor: Richard Hillis

Co-supervisor: Peter van Ruth

Scholarship support: CO2CRC

Project Description

Rising concern over greenhouse gas emissions has led to the investigation of potential carbon dioxide (CO2) emission reduction technologies. Geological storage is a potential method for reducing CO2 emissions. Sizeable volumes of CO2 may be geologically stored by pressurizing the gas to a supercritical state and injecting into potential storage sites. Numerous studies have been conducted to determine the viability of geological storage in Australia. Such studies have shown that there are numerous potential sites for geological storage of CO2 including the Otway Basin.

Many geological issues must be considered when identifying a safe storage site for storage of CO2. Such issues include stratigraphic modeling, flow modeling and geomechanical modeling. This Ph.D. project will research the geomechanical modeling of potential CO2 storage sites.

Many studies have shown that increases in pore fluid pressure can reduce fault strength and ultimately induce reactivation. Geomechanical modeling is conducted to determine the stability of faults with increased fluid pressures due to injection of CO2. Such reactivation in CO2 storage sites could potentially lead to unpredictable migration of the CO2. Geomechanical modeling requires the determination of the in situ stress field and ambient pore pressures, which are generally obtained from drilling data, as well as the orientations and frictional properties of existing faults.

Many geomechanical risking parameters are presently used to determine the likelihood of faults to reactivate such as FAST, dilation tendency and slip tendency. However, it is somewhat difficult to calibrate such parameters when applied to faults within the earth's crust as supporting empirical field data is difficult to obtain. This Ph.D. aims to investigate the link between geological risking parameters and the movement of naturally occurring CO2 along faults. The geometry of faults which act as boundaries to natural carbon dioxide accumulation will be determined using a 3D seismic dataset. Frictional properties of the intact rock and fault zone will also be ascertained. Risking parameters will be used to determine segments of the fault that are at orientations which are more likely to be open to the flow of CO2. Natural concentrations of CO2 in the soil above the fault will then be sampled and compared with the sections of the fault more likely to conduct CO2 as defined by the risking parameters.