Perth Basin (Australia)
Resource Project Development (Exploration and/or Appraisal)
Exploration Permit EP 437
Since award in November 2004, CalEnergy has been a substantial interest holder in onshore exploration permit EP 437,
located approximately 350 kilometers north of the city of Perth, Western Australia. CalEnergy has farmed out a 45 percent
interest in the permit and commenced a drilling campaign for two wells in early 2011. No commercial hydrocarbons were
encountered, and both wells were plugged and abandoned. The joint venture will review and integrate the drilling results
and review the remaining prospectivity in the block.
Exploration Permit EP 408
Exploration Permit EP 408 is located in the onshore Southern Perth Basin, approximately 280 kilometers south
of Perth, Western Australia. The permit contains the Whicher Range and Wonnerup gas fields, which were discovered in
1968 and 1971, respectively.
The Whicher Range structure is a large, well-delineated gas field. Seismic data and the drilling of five
exploration/appraisal wells has defined the field, extending beyond a 100 square-kilometer area, a gross hydrocarbon
column height of 650 meters.
In 2011, CalEnergy Resources (Australia) Ltd entered into a farm in agreement to earn up to 50 percent participating interest
in EP 408 with Whicher Range Energy (Operator) to undertake a phased appraisal and development work program. The
proposed appraisal program addresses key uncertainties for the Whicher Range field:
- Ability to enhance productivity by drilling underbalanced (diesel) wells
- Confirmation of volumetrics
- Reservoir characterisation
To address the first key uncertainty, the joint venture intends to re-enter Whicher Range-4 and sidetrack
the well using underbalanced drilling techniques in 2012. An extended well test will be conducted to evaluate
sustained production performance. On the assumption that underbalanced drilling enhances productivity, the appraisal
program will progress to address volumetrics, development concept definition and commercialization.