| SORELL BASIN | ||
|---|---|---|
| State | Tasmania | |
| Area (km2) | Offshore | 90,000 |
| Onshore | 0 (if Macquarie Harbour Graben excluded) | |
| Maximum thickness (m) | 6500 | |
| Age range | Cretaceous to Cainozoic. | |
| Basin | Overlies | Proterozoic and early Palaeozoic basement. |
| Underlies | - | |
| Subdivisions | King Island, Sandy Cape, Strahan, Port Davey and Toogee Sub-basins. | |
| Other | The northern King Island Sub-basin's boundary with the Otway Basin is gradational. To the east, the Macquarie Harbour Graben is sometimes included in the Sorell Basin. | |
| Indicators | Size | C3 (Medium basin) |
| Induration | 1 (seabed) - 8 | |
| Knowledge | 4 (Regional geophysical and some well data) | |
| Basin Type | Plate margin rift and drift | |
| System(s) | Austral. | |
| Water depth (m) | 50 - 4500 | |
| Exploration | Status | Frontier |
| Wells | 2 petroleum exploration | |
| Seismic line-km | Not determined, but sparse except in Strahan SB. | |
| Discoveries | Nil | |
| Shows | Oil and gas shows in Cape Sorell-1 | |
| HC evidence | Flat spots on seismic (Strahan SB); geochemical surveys recorded thermogenic hydrocarbons. | |
| Reserves | Produced | Oil | - | Gas | - |
| Condensate | - | LPG | - | ||
| Proven/probable | Oil | - | Gas | - | |
| remaining | Condensate | - | LPG | - |
| Geology | Source(s) | Postulated Early Cretaceous lacustrine and coaly facies; Late Cretaceous shales if mature. |
| Reservoirs | Numerous sandy facies of Early Cretaceous to Eocene ages. | |
| Seals | Early Cretaceous to Eocene intraformational shales; Oligocene marls. There is no truly regional seal. | |
| Trap types | Fault blocks and drape over them, anticlines and faulted anticlines, fault traps, & stratigraphic traps probable. |
| Palaeogeographic summary | Insufficient data for a meaningful assessment. Similar environments to the Otway Basin probable. | |
| Timing | Oil generation | Late Cretaceous - (?) Palaeogene modelled for the Early Cretaceous section in the Sandy Cape SB. |
| Gas generation | Palaeogene to Neogene (for section as above). | |
| Trap formation | Early Cretaceous to Palaeogene. | |
| Other key times | Mid-Cretaceous (?Cenomanian) unconformity; first marine deposition occurred in the Late Cretaceous. | |
| For more web information | Mineral Resources Tasmania (MRT) | |