A surface characterisation of the Arnager Greensand in south Sweden, a deep saline aquifer found to be suitable for geological storage of CO2 or energy storage, was undertaken in this thesis. Vintage seismic reflection data only available as scanned tiff images of the final stacked sections were digitized and processed using modern interpretation software to provide new insights into the morphology of the Arnager Greensand and to analyse the reservoir’s potential as an energy storage unit. The primary energy storage method discussed and evaluated was Compressed Air Energy Storage (CAES). This is a modern energy storage method developed as a tool for regulating inherently intermittent renewable energy sources. Such methods are key to the growth of the renewable sector and for providing a competitive alternative to fossil fuels. Moreover, in comparison with other energy storage methods such as battery storage, CAES is known to have strong potential to deliver highperformance energy storage at large scales for relatively low costs compared with any other solution. Previous studies conducted in the 1980’s by Swedegas produced a 2D isochrone surface map of the Arnager Greensand by hand interpolation methods utilizing analogue data collected by Oljeprospektering AB (OPAB, currently Svenska Petroleum). The Geological Survey of Sweden (SGU) has now transferred a vast amount of the historical OPAB dataset to modern digital format. This thesis contributes to those efforts and seeks to find new interpretations from the vintage data. A more comprehensive 3D model of the top of the Arnager Greensand employing the application of modern interpretation software was produced in this study. Strong similarities between morphology and dip-trend have been observed between the surface model generated in this report and the historical Swedegas isochrone surface map. Reservoir properties such as thickness, porosity and permeability gleaned from the earlier reports show the Arnager Greensand to exhibit excellent potential as a storage unit. Preliminary effective capacity estimates by Nordic CCS Competence centre show the Aranger Greensand to be one of the top three storage aquifers in Sweden. These positive appraisals highlight the need for a better characterization of the Aranger Greensand through data digitization and modern interpretation means. This thesis contributes to that endeavour.

>Magister Scientiae - MSc / The North West Shelf of Australia is a prolific gas province. The Thebe Gas Field is situated within the northern central Exmouth Plateau in the Northern Carnarvon Basin. The Exmouth Plateau is a submerged continental block whose culmination lies at about 800m below sea level. The seismic data used for this study is the HEX07B survey which was conducted in 2007. The objective of this study was to interpret all available seismic data, of which six horizons were picked, generating two-way-time structure maps and an average velocity map, performing depth conversion and generating various depth maps. The horizons picked were the economic basement, Triassic Mungaroo, Murat Siltstone, Muderong Shale, Gearle Siltstone and the Sea Bed. The horizon of interest was the Triassic Mungaroo Formation and therefore it was the only horizon with an average velocity map. The seismic sections were used in conjunction with the structure maps generated to identify possible locations for appraisal wells to be drilled. Prospect X was identified on the basis of amplitude and structure present within the Triassic Mungaroo Formation. The final task was to calculate the volumes present and a Monte-Carlo Simulation was used for this. The results obtained showed that Prospect X has a good petroleum system in place. The Mungaroo Formation is identified as being the possible source and reservoir rock, the Muderong Shale is the seal, structural traps are provided by large fault block and faults provided the migration pathways from the source in to the reservoir. The volumes were calculated using three areas identified on the structure maps by three closing contours. These areas are the P90, P50, P10 and the volumes for the gas in place were as follows, P90 = 893 Bcf (0.9Tcf), P50 = 1128 Bcf (1.1 Tcf), P10 = 1367 Bcf (1.4Tcf). Using the various parameters the probability of success for Prospect X was calculated to be 20%.