Legacy product - no abstract available

Legacy product - no abstract available

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four Periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four Periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four Periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four Periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four Periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

During the period 1984-1996, AGSO compiled and produced a series of Palaeogeographic atlases of Australia for the Phanerozoic Eon. The Atlases - Cambrian, Ordovician, Silurian, Permian, Jurassic, and Cainozoic - contained maps which summarised the most important sedimentological data extracted from a wide variety of sources. Due to time and resource constraints four periods (Devonian, Carboniferous, Triassic and Cretaceous) were not published, although data were compiled. Atlases consisted of a series of Data and Interpretation maps a Structure map, and supporting Stratigraphic Columns and text. Maps were compiled at a scale of 1:5 000 000 and digitally produced using MicroStation CAD software. The PALAEOGEOGRAPHIC ATLAS OF AUSTRALIA dataset has resulted from the conversion of the CAD atlas maps from all ten atlases into a format compatible with GIS applications. Important CAD elements such as lithology patterns have been retained for visualisation purposes. It is envisaged that this Palaeogeographic dataset will become part of the AGCRC Australia's Geodynamic Framework project.

The Early Cretaceous Gage Sandstone and South Perth Shale formations are a prospective reservoir-seal pair in the Vlaming Sub-basin. Plays include post-breakup pinch-outs in the Gage Sandstone with the South Perth Shale forming top seal. The Gage reservoir has porosities of 18-25% and permeabilities of 1-1340 mD. It was deposited in palaeotopographic lows of the Valanginian breakup unconformity and is the lowstand component of the thick deltaic South Perth (SP) Supersequence. To characterise the reservoir-seal pair, a detailed sequence stratigraphic analysis was conducted by integrating 2D seismic interpretation, well log analysis and new biostratigraphic data. Palaeogeographic reconstructions for the SP Supersequence were derived from mapping higher-order prograding packages and establishing changes in sea level and sediment supply. Higher resolution Gage reservoir reconstructions were based on seismic facies mapping. The Gage reservoir forms part of a sand-rich submarine fan system similar to model proposed by Richards et al (1998). It ranges from canyon confined inner fan deposits to middle fan deposits on a basin plain. Directions of sediment supply are complex, with major sediment contributions from a northern and southern canyon adjacent to the Badaminna Fault Zone. The characteristics of the SP Supersequence differ markedly between the northern and southern parts of the sub-basin due to variations in palaeotopography and sediment supply. Palaeogeographic reconstructions reveal a series of regressions and transgressions leading to infilling of the palaeo-depression. Palaeogeographic reconstructions for the SP Supersequence portray a complex early post-rift depositional history in the central Vlaming Sub-basin. The developed approach is applicable for detailed studies of other sedimentary basins. APPEA

Introduction This National Carbon Infrastructure Plan study assesses the suitability of the Vlaming Sub-basin for CO2 storage. The Vlaming Sub-basin is a Mesozoic depocentre within the offshore southern Perth Basin, Western Australia (Figure 1). It is around 23,000 km2 and contains up to 14 km of sediments. The Early Cretaceous Gage Sandstone was deposited in paleo-topographic lows of the Valanginian breakup unconformity and is overlain by the South Perth Shale regional seal. Together, these formations are the most prospective reservoir/seal pair for CO2 storage. The Gage Sandstone reservoir has porosities of 23-30% and permeabilities of 200-1800 mD. It lies mostly from 1000 - 3000 m below the seafloor, which is suitable for injection of supercritical CO2 and makes it an attractive target as a long-term storage reservoir. Methods & datasets To characterise the Gage reservoir, a detailed sequence stratigraphic analysis was conducted integrating 2D seismic interpretation, well log analysis and new biostratigraphic data (MacPhail, 2012). Paleogeographic reconstructions of components of the Gage Lowstand Systems Tract (LST) are based on seismic facies mapping, and well log and seismic interpretations. Results The Gage reservoir is a low stand systems tract that largely coincides with the Gage Sandstone and is defined by the presence of the lower G. mutabilis dinoflagellate zone. A palynological review of 6 wells led to a significant revision, at the local scale, of the Valanginian Unconformity and the extent of the G. mutabilis dinoflagellate zones (MacPhail, 2012). G. mutabilis dinoflagellates were originally deposited in lagoonal (or similar) environments and were subsequently redeposited in a restricted marine environment via mass transport flows. Mapping of the shelf break indicates that the Gage LST was deposited in water depths of >400 m. Intersected in 8 wells, the Gage LST forms part of a sand-rich submarine fan system (Figure 2) that includes channelized turbidites, low stand fan deposits, debris flows (Table 1). This interpretation is broadly consistent with Spring & Newell (1993) and Causebrook (2006). The Gage LST is thickest (up to 360 m) at the mouth of large canyons adjacent to the Badaminna Fault Zone (BFZ) and on the undulating basin plain west of Warnbro 1 (Figure 1). Paleogeographic maps depict the evolution of the submarine fan system (Figure 3). Sediment transport directions feeding the Gage LST are complex. Unit A is sourced from the northern canyon (Figure 3a). Subsequently, Unit B (Figure 3b) derived sediment from multiple directions including incised canyons adjacent to BFZ and E-W oriented canyons eroding into the Badaminna high. These coalesce on an undulating basin plain west of Warnbro 1. Minor additional input for the uppermost Unit C (Figure 3c) is derived from sources near Challenger 1. Summary 1: The Gage LST is an Early Cretaceous submarine fan system that began deposition during the G. mutabilis dinoflagellate zone. It ranges from confined canyon fill to outer fan deposits on an undulating basin plain. 2: The 3 units within the Gage LST show multidirectional sediment sources. The dominant supply is via large canyons running north-south adjacent to the Badaminna Fault Zone. 3: Seismic facies interpretations and palaeogeographic mapping show that the best quality reservoirs for potential CO2 storage are located in the outer fan (Unit C sub-unit 3) and the mounded canyon fill (Unit A). These are more likely to be laterally connected. 4: The defined units and palaeogeographic maps will be used in a regional reservoir model to estimate the storage capacity of the Gage LST reservoir.