During 2011 Archer applied for an Exploration Licence covering 885km2 of ground to the southwest of Leigh Creek and stretching to the east of Lake Gairdner. The tenement is granted as EL 4869.
The application excludes all ground associated with the Ediacara Fossil Reserve.
The tenement was initially applied for to cover areas where historical exploration was focused on base metals, industrial minerals and coal.
In 1983, the Commonwealth Aluminum Company (Comalco) whilst exploring for northern and southern extensions to lead and copper mineralisation found within the reserve, intersected lignitic material in three holes;
CT1 (located in the north of the ELA); and CT2 and CT3 (located some 8km inside the SW boundary), figure 2. Other holes that have historically intersected lignitic material are also shown on figure 3.
Hole CT1 intersected sandy lignite and lignite from 256m to 289m below competent and firm transported clay.
Hole CT2 intersected sandy lignite and lignite from 254m to 290m below competent and firm transported clay.
Hole CT2 intersected sandy lignite and coal fragments from 234m to 244m below competent and firm transported clay and recorded two wide intervals of lignite and coal:
- 264 to 276 sandy lignite
- 298 310m (EOH) clay with sub bituminous coal
All the CT holes appear to reside on the western side of the Ediacara Range. The consistency of intercepts in terms of depth and thickness strongly suggest the lignite and coal intercepts are from one deposition environment.
No additional exploration was performed by Comalco in the areas of the CT holes for coal and or lignite.
Subsequent to the ELA, Archer through a wholly owned subsidiary, Archer Energy and Resources Pty Ltd, applied for a PELA (567) to cover the prospective area of lignite.
Remnant drill samples for the CT holes exist with PIRSA. It is Archer’s intention to recover the lignitic material with a view to determine the amenability of the material for gasification or other products once the tenement has been granted.