The Canning Basin, located on the northern coast of Western Australia, is one of Australia’s largest basins at over 400K sq. km (figure 1), two times the size of the Permian Basin of Texas and New Mexico. It is adjacent to the prolific offshore Carnarvon Basin. A limited number of wells have been drilled with only marginal success on the basin margins bounding the northern deep Fitzroy Trough depocenter. Prograding Devonian and Carboniferous marine carbonates and siliciclastics were deposited in a transitional ramp setting in the Fitzroy Trough; defined source rocks with TOCs of .5 to 4.25% lie within this depocenter but limited information is known about the potential deeper sources. Multiple tectonic phases altered this basin, creating an extensive set of both transpressional and extensional fault systems. In the Canning Basin, the Australian government estimates potential tight gas resources are 74 TCF, and that an additional 70-150 TCF of shale gas resources are geologically and technically producible. This is approximately equal to the USGS assessed resource size for the entire US Marcellus shale gas system. Unconventional discoveries like those found in North America have shown that there is significant potential for basin-centered gas around the Fitzroy Trough. Due to Australia’s needs for natural gas, both to feed the declining conventional feedstocks for export, as well as for meeting domestic energy needs, several vertical wells have been stimulated in the last 10 years demonstrating the gas potential within the basin-centered gas play. Using prior work that was undertaken to develop a geological understanding of the Canning Basin, a US operator has initiated a new evaluation, including a large 3D seismic program (circa ∼200 sq. miles), with a commitment to future testing, drilling and stimulation of unconventional wells to help better define and understand the play with an eye toward economic production. Introduction Using the wealth of prior work that was undertaken to develop an understanding of Canning Basin geology, Black Mountain Exploration has initiated a fresh, robust evaluation of the basin-centered play within a large exploration permit along the northern margin of the Canning Basin within the Fitzroy Trough (Figure 2). This evaluation has included extensive utilization of the existing data within the northern part of the basin and will include a future acquisition of a large 3D seismic program. With this evaluation is a commitment to future testing, drilling and stimulation of unconventional wells to help better define the resource play. A review of the geochemical, petrophysical and vintage 2D seismic data establishes an extensive basin-centered gas fairway beginning at 2000m and continuing to over 4500m in depth. This fairway steps down from the basin margins into the depths of the Fitzroy Trough and is analogous and correlative to a similar petroleum system that hosts significant gas discoveries on the opposite margin of the trough.

Abstract Bulk trapped fluid content data acquired from fluid inclusion analysis of more than 7,000 cutting samples from 26 wells onshore Canning Basin, Australia (Figure 1; Table 1), provide insight into the hydrocarbon potential of this largely unexplored basin. Although key unconventional targets are thought to reside within the Ordovician section, exploration risks include the thickness, distribution, and presence of producible reservoir; source distribution and maturity; and the ability to stimulate reservoirs. Samples examined in this study range in age from Cretaceous to Ordovician (Figure 2). The overall analysis of samples employed X-ray fluorescence (XRF) to determine inorganic elemental composition. Fluid inclusion petrography and microthermometry analyses were performed on intervals selected on the basis of initial bulk fluid inclusion analysis results. The resulting data allowed evaluation of the vertical and lateral distribution of hydrocarbons and nonhydrocarbon volatiles, oil gravity values, phase state, salinity, and burial temperature. Homogenization temperatures above current reservoir temperatures are present in many of the petroleum and aqueous fluid inclusions, suggesting that fluids dropped through bubblepoint during uplift of 1000–1800 m and current reservoir fluids are likely dual-phase. Maturity values calculated from fluid inclusion data generally range from 0.6 to 1.3% vitrinite-equivalent. Regional variability in maturity within potential source intervals leads to variable fluid composition, with estimates that API oil gravity values (based on fluid inclusions) can range from 28 to 45°, although most measured values range from 37 to 44° API gravity. Data indicate source rock potential in the Upper Ordovician Bongabinni Formation of the Carribuddy Group, Upper Ordovician Nita Formation, Middle Ordovician Goldwyer and Willara Formations, and the Lower Ordovician Nambeet Formation. Lateral and vertical distribution is not uniform within these units, and the prospectivity of the Ordovician Nita-to-Nambeet section is verified. Several formations within the Canning Basin exhibit potential for conventional exploration, including: Middle Jurassic Wallal Sandstone, Lower Permian Grant Group Sandstones, Devonian Tandalgoo Sandstone, Upper Ordovician Nita Formation, Middle Ordovician Willara Formation and Lower Ordovician Nambeet Formation. The study identified the presence of migrated and locally generated fluids, including a deep-sourced mature gas phase that appears to have invaded portions of the basin. The occurrence of shallow bacterial microseeps suggests associated deeper accumulations are present. It is anticipated that accumulations will be classified as combined conventional and unconventional reservoirs. The study identified multiple, individual targets, which vary geographically, indicating the need for a directed approach to optimize drilling and completion.

Abstract The Kidson Sub-basin lies within latitudes 20°S and 24°S and longitude 123°E and 128°E and is one of the depocentres formed during the development of the Canning Superbasin in the Early Paleozoic in Western Australia. Hydrocarbon discoveries have been made over the years in some parts of the Canning Superbasin but none in the Kidson Sub-basin. This report evaluates the prospectivity of Kidson Sub-basin for unconventional hydrocarbon resources. The Kidson Sub-basin has a sedimentary section thickness reaching up to over 7000m, mainly of Paleozoic age. Using the available well data three unconventional shale gas plays within the Goldwyer, Bongabinni and Noonkanbah shales are interpreted to meet all the necessary requirements for hosting shale gas accumulations. A pseudo-well modelled near the centre of the Kidson Sub-basin shows that the organically-rich Noonkanbah Formation is mature enough to generate gas and 1-D modelling of the Kidson-1 well indicates that both the Bongabinni and Goldwyer Formations are also presently in the gas window. The prospective resources of the unconventional shale plays are estimated using geochemical approach. The Goldwyer Shale is estimated to contain potential gas in-place (GIIP) of about 13.4TCF over the most prospective area of Kidson Sub-basin estimated to be around 567 km2. The Bongabinni Shale is organically-rich and about 324 km2 is estimated to be prospective in the Kidson Sub-basin. About 205 km2 is estimated to be prospective in the centre of Kidson Sub-basin where Noonkanbah Shale is deeply buried to a depth up to 1600m. The three shale plays have mid range gross prospective resources of 31.0 TCF of gas. The current skilled labour shortage in Australia may pose a big challenge in shale gas production as this will lead to higher drilling costs compared to those of United States. In addition, Kidson Sub-basin is a desert and water scarcity will be another challenge for shale gas production since water is required for fraccing.