Bonaparte CO2 Storage Project
The Australian Government has provided funding through the National Low Emissions Coal Initiative for Geoscience Australia to assess the prospectivity for geological storage of carbon dioxide in the Bonaparte Basin, with particular focus on the Petrel Sub-basin.
The Petrel Sub-basin was identified by the Carbon Storage Taskforce in 2009 as a prospective region for the geological storage of CO2 due to favourable geology and proximity to an emerging LNG industry near Darwin (Figure 1). The area was also the site of two former exploration blocks offered through the 2009 Release of Offshore Areas for Greenhouse Gas Storage Assessment, under the Offshore Petroleum and Greenhouse Gas Storage Act 2006.
The Petrel Sub-basin is a northwest-trending Paleozoic rift within the southern Bonaparte Basin, located offshore northwestern Australia in the Joseph Bonaparte Gulf. The geological reservoirs of interest include the Jurassic Plover Formation and the Early Cretaceous Sandpiper Sandstone. Primary and secondary seals of interest include the Late Jurassic Frigate Formation and the Cretaceous Bathurst Island Group (regional seal). Water depths are generally less than 100 metres, and depths to reservoir/seal pairs range between 300-2500 metres below the sea surface.
The Bonaparte CO2 Storage project started in July 2011. The project comprises four stages over two years. The first stage, now completed, identified the critical geoscience issues affecting the CO2 geological storage prospectivity of the area. The second stage involved the acquisition of pre-competitive data, which was completed between May and June 2012. The third and fourth stages are currently underway and involve the integration and assessment of all data and interpretation of results. The final report for the Bonaparte CO2 Storage project is expected to be delivered in mid 2013.
Achievements to Date
The Bonaparte CO2 Storage project has already identified the most relevant/important geoscience issues affecting the CO2 storage prospectivity of the Petrel Sub-basin. During 2012 Geoscience Australia undertook two major surveys off the coast of the Northern Territory in the Petrel Sub-basin, acquiring 2D seismic and marine data. The seismic survey covered an area of 4091km (Figure 2), and was supported by a marine survey investigating the shallow geology and seabed in two key locations of geological relevance to the underlying substructure and basin history of the region.
Petrel Sub-basin CO2 Storage Seismic Survey (GA336)
High resolution multichannel seismic data were acquired between 3 May and 24 June 2012 on the MV Duke. The seismic data have been processed focusing on enhancing stratigraphy in the shallower (<1000m below sea floor) formations.
- 4091 line kilometres of seismic reflection
- 4 second record length
- 2 millisecond sample rate, 408 traces
- 5100 metres solid streamer
- 12.5 metre shotpoint and 12.5 metre group interval
- Source depth: 4 metres; streamer depth: 5 metres
- 2080 cubic inch gun array at 2000 psi
- 8000 line kilometres of multibeam swath bathymetry
Petrel Sub-basin Marine Survey (GA335)
The marine survey, conducted in collaboration with the Australian Institute of Marine Science (AIMS), was completed in May 2012. This survey targeted two study areas to investigate possible links between geological formations suitable for CO2 storage and the shallow geology and seafloor. Data acquired includes 5300 line kilometres of multibeam swath bathymetry, 655 line kilometres of sub-bottom profiler data, underwater video and still images from 11 sites, and seabed sediment and biological samples from 15 sites. Datasets available include:
- Ecology/Seabed underwater video footage and still images
- High Resolution Bathymetry Grids
- Seabed Geochemistry/Porewater TCO2 and TCO2 flux
- Seabed Geochemistry/Chlorins
- Seabed Geochemistry/Chlorophyll abc and pheaophytin
- High Resolution Multibeam Sonar Seabed Backscatter Grids
- Seabed Geochemistry/TOC, TN and carbon and nitrogen isotopes
- Seabed Geochemistry/Sediment Oxygen Demand
- Seabed Geochemistry/Specific surface area and total carbonate
- Ecology/Infaunal morphospecies identifications
- Seabed Sediment Grain Size Data
- Sub-bottom profiles
Initial data analysis has been undertaken and a post-survey report detailing survey location, methodologies and initial findings is available.
Petrel Sub-basin CO2 Data Package
The 2D seismic data (GA336), together with the marine survey data (GA335) can be ordered from the Data Repository [ PDF 552KB]. Select datasets from the list above can also be downloaded from our website.
Topic contact: firstname.lastname@example.org Last updated: December 5, 2012