Penrhyn Coal Project
EL 5718 Robins Rise is both a hard rock minerals and coal tenement that covers the partially defined Penrhyn sub-bituminous coal deposit. The Penrhyn deposit is situated 40 km south of Coober Pedy and 11 kilometres from the Adelaide to Darwin rail line. The tenement is held 100% by Southern Coal Holdings Pty Ltd, (SCH) a wholly owned subsidiary of WPG.
EL 4908 Perfection Well covers an area of 458 square kilometres and is also prospective for the discovery of new coal deposits in the Arckaringa Basin sediments.
Geology & exploration
The Penrhyn coal deposit was discovered in 1995 as part of the South Australian Exploration Initiative and was subsequently explored by the South Australian Steel and Energy (SASE) joint venture. The deposit lies within the Arckaringa Basin and the quality of the sub-bituminous coal is generally similar to other Arckaringa Basin coals. Estimated dimensions of the Penrhyn trough are 25 kilometres long by 3 kilometres wide.
In early 2010 WPG completed a traverse of four diamond drill holes across the width of the Penrhyn Trough. The two central holes intersected several coal seams of varying thicknesses and confirmed the results of the historical, mostly open hole, drilling done by PIRSA and reinforced the potential for a coal deposit of significant size.
In June 2011 WPG followed up the encouraging results from the 2010 drilling with a systematic program of resource definition drilling comprising 19 open holes and 12 diamond drill holes for a total of 4,636 metres drilled. Results defined four significant coal seams together with two coal bearing stratigraphic horizons that are host to between two and four seams. The relatively flat lying coal seams are in places up to 8 metres thick and lie at depths ranging between 60 and 145 metres beneath a 60 metre deep sequence of Eromanga Basin sediments and surficial cover.
A typical cross section through the Penrhyn deposit and an orthographic projection of the L (green), J (pink) and R (grey) seams together with the drill hole traces are shown in the following two diagrams. Note that the vertical scale in both figures has been exaggerated by a factor of 10, so that the stratigraphy can be better illustrated. The line of the cross section is shown in red on the drill hole location diagram below.
The results of the drilling provided sufficient data for a maiden JORC compliant resource estimate. The estimate was based on detailed geological logging and interpretation of chips and PQ core, seam correlation and 3-D modeling, assisted by results of down hole multi-probe geophysical logging that was carried out in each of the drill holes.
The total identified coal resource at Penrhyn is 352.4 million tonnes.
Details for each of the resource categories are shown in the following table.
|Measured coal resource||185.4|
|Indicated coal resource||150.5|
|Inferred coal resource||16.5|
|Total coal resource||352.4|
The zone covered by the recent resource drilling program is shown in the following diagram and covers an area of approximately 21sq km. This area is approximately 28 percent of the total area of the Penrhyn Trough held under tenure in EL 5718.
The drilling program in combination with results from historical drilling and regional magnetic and gravity data has also enabled 5 additional areas to be outlined, each with good potential for extensions to the known coal seams. These blocks extend out from the defined resource zone and when combined form a new exploration target that is estimated to be in the range of 300 to 330 million tonnes.
The information pertaining to the Penrhyn coal project resource and exploration target together with the accompanying competent person statement was first disclosed by WPG Resources Ltd under the JORC Code 2004 in the report entitled “Maiden 352.4 million tonne coal resource estimate for Penrhyn deposit” released on 7 July 2011. The report is available to view on the Company’s website at www.wpgresources.com.au and at www.asx.com.au. It has not been updated since to comply with the JORC Code 2012 on the basis that the information has not materially changed since it was last reported.