| YEAR | SURVEY | REFERENCES |
|---|---|---|
| 1967-1970 | Industry seismic data on the continental shelf shot by Esso Australia. | Moore, 1991 |
| 1967 | Drilling of Prawn-1 in southeastern Otway Basin (dry). | Culp, 1967 |
| 1969 | Drilling of Clam-1 in the King Island Sub-basin (dry). | Lunt, 1969 |
| 1970 | Drilling of Whelk-1 in southeastern Otway Basin (dry). | Davidson, 1970 |
| 1972 | First systematic seismic survey (Survey 16) of the west Tasmanian margin conducted by the Bureau of Mineral Resources (BMR). | Tilbury, 1974 |
| 1973 | Deep-water reconnaissance lines shot across the west Tasmanian margin by Shell International Petroleum. | Shell 1993; Boeuf and Doust 1975 |
| 1973 | Leg 29 of the Deep Sea Drilling Program (DSDP) was conducted. Site 282 was drilled on the lower continental slope off the central west coast of Tasmania. | Kennett, Houtz et al. 1975a |
| 1981 | Amoco Australia Oil Company carried out semi-detailed seismic exploration in the Strahan Sub-basin. | Amoco, 1981 |
| 1982 | Drilling of Cape Sorell-1 in Strahan Sub-basin (strong free oil shows). | Amoco, 1982a |
| 1982, 1985, 1987 and 1989 | Multichannel seismic surveys (Surveys 40, 48, 78 and SO36) shot the northern Sorell Basin. BMR Survey 67 in the Otway Basin and over the far NW Tasmanian margin sampled the seafloor. Hydrocarbon concentrations were measured in core samples of young sediments during surveys SO36, 67 and 78. | Hinz et al. 1985; Exon, Williamson et al. 1987; Exon et al. 1989; Exon, Lee et al. 1992 |
| 1990 | Maxus Energy Corporation acquired a substantial infill grid, plus two semi-regional lines and mapped the Strahan Sub-basin. | Maxus 1993; Conolly and Galloway 1995 |
| 1994 | Swath Mapping and seismic data acquired by AGSO (Tasmante Survey 125). Aeromagnetics acquired over the northwest and most of T98-1 and T98-2. | Exon et al. 1994, Hill et al. 1997a; AGSO 1995; Mackey et al. 1995; Gunn et al. 1996 |
| 1994-1995 | Aeromagnetics, seafloor swath-mapping and deep crustal seismic acquired by AGSO. | Hill et al. 1997b |
| 1994/1995 | Regional deep-crustal seismic (Survey 137) conducted by AGSO in the Otway Basin including the northern Sorell Basin. AGSO Survey 147 conducted geological sampling of the seafloor over the west Tasmanian margin, South Tasman Rise and East Tasman Plateau. | Blevin et al. 1995; Exon, Marshall et al. 1995 |
| 1995 | Circum-Tasmania Survey 148 conducted under the National Geoscience Mapping Accord (NGMA). Survey 159 shot over the southern Sorell Basin and northern STR. | Hill et al. 1995c |
| 1995-1997 | High resolution satellite gravity data based on ERS-1 and declassified Geosat geodetic altimeter missions. | Sandwell and Smith 1997; Smith and Sandwell, 1995 |
| 2001 | Otway/Sorell Part 1 - Seismic Survey conducted by Fugro/Woodside Petroleum |
Data used to determine petroleum prospectivity is not evenly distributed within the Sorell Basin. Well data is restricted to the central and northern parts of the Sorell, within the King Island and Strahan Sub-basins and to grab samples on the western margin. Most of the seismic coverage is concentrated in the Strahan Sub-basin. Widely spaced regional lines cover the rest of the basin. Much of the prospectivity discussion is focused on the Strahan Sub-basin, but potential can also be postulated for other parts of the Sorell Basin.
| Well Name | Cape Sorell-1 | Clam-1 | ODP Site 1168 | DSDP Site 282 |
|---|---|---|---|---|
| Permit | T98-1 | T01-2 | - | - |
| Location | Strahan Sub-basin | King Island Sub-basin | Western slope off Tasmania | Magnetic Quiet Zone, west Tasmania |
| Status | Dry - P&A | Dry - P&A | P&A | P&A |
| UNO | W7820002 | W7690001 | - | - |
| Operator | Amoco Aust. Explor. | Esso Exp. & Prod. Aust. | OPD Leg 189 | DSDP Leg 29 |
| Latitude | 42.136111 S | 40.864561 S | 42°36.5809´S | 42° 14.76' S |
| Longitude | 145.029722 E | 144.21532 E | 144° 24.7620' E | 143° 29.18' E |
| Spud Date | 5 July 1982 | 19 July 1969 | 17 March 2000 | 5 April 1973 |
| TD Date | 2 September 1982 | 3 August 1969 | 26 March 2000 | 8 April 1973 |
| TD (mKB) | 3528 | 1622 | 3357.7 | 4527.5 |
| Water Depth (m) | 94 | 120 | 2463.3 | 4202 |
| Datum (KB) | 22 | 30 | 11.2 | 15 |
| Core | 3480.82-3482.95m (1.49m recovered) | 416-418 metres (0 metres rec)
418-425 metres (0 metres rec) 867-868 metres (0.6 rec) 962-965 metres (2.9 metres rec) 1365-1374 metres (3.4 metres rec) 1620-1622 metres (2.1 metres rec) |
3 holes drilled and 130 cores
Total length of cored section was 1282.4 metres (with 92.9% recovery) |
20 cores
Total length of cored section was 295 metres (with 38% recovery) |
| Discoveries | None |
|---|---|
| Shows | Oil stains were reported in the Late Cretaceous sediments below 3000 metres in Cape Sorell 1
(Boreham et al. 2002). Minor amounts of free oil were recorded in sandstone and claystone sediments at
the top of the lower sandstone sequence and base of the conglomeratic sandstone between 3087 and 3136 metres,
while residual oil traces were observed as deep as 3440 metres (Amoco, 1982). No zones in Cape Sorell 1
warranted drill stem testing. A repeat formation test was run in the 8½ inch section over the open hole
interval 2743.81-3528.36 metres - no formation fluids were recovered (WCR).
No formation or production tests were carried out in Clam 1 (WCR). |
| Accumulations | None |
| Fields | None |
| Statistics | No production or reserve statistics exist for wells in the Sorell Basin |
| Other Resources | None |