IN WESTERN AUSTRALIA - Department of Mines and Petroleum

Review of 2003
Exploration, Production and Development Activities in Western Australia
During the 2003 calendar year, 77 petroleum
wells were drilled in Western Australia;
comprising 14 development wells, 21 extension
wells, and 42 new field wildcat wells. This level of
activity marks a significant increase on the
previous year, where 51 wells were drilled. This
has brought the State back to the high level of
drilling activity seen in 2000 and 2001 where 75
wells were drilled in each of those years. The
current level of activity is partly attributable to the
continuing high oil price and improvements in the
gas sales market. On a national level, Western
Australia has attracted over 70% of Australia’s
petroleum exploration expenditure during the
year, indicating the State remains the most
prospective area of Australia for new petroleum
finds (Figure 1).
Activity in the Perth Basin, particularly the northern
portion of the basin, remains high, buoyed by the
Cliff Head, Hovea and Jingemia discoveries in 2002
(Figure 2). During 2003, three onshore and three
offshore exploration wells were drilled, along with
10 development and extension wells drilled onshore
and two extension wells drilled offshore as part of
the Cliff Head project. Of the onshore exploration
wells, Eremia 1 proved to be a success for ARC
Energy just to the northwest of their Hovea
discovery, while Eclipse 1 and Leafcutter 1 had
some interesting gas shows, but were abandoned
as non-economic. The Northern Carnarvon Basin
continues to be the centre of exploration and
development activity, with 31 of the 42 wildcat wells
drilled in 2003 located in that basin, and 22
development and extension wells spudded in the
basin. A number of significant discoveries were
made, including oil pools discovered by the BHP
Billiton Petroleum (BHPBP) wells Stybarrow 1,
Ravensworth 1 and Crosby 1 (Figure 3). Four
exploration wells were spudded in the Browse
Basin, two of these discovering gas in Inpex’s
WA-285-P permit, with the Ichthys 2 extension well
drilled in November to assess the gas discovery
made by Ichthys 1 in June. The sole exploration well
in the offshore Bonaparte Basin, Woodside’s Weasel
1, was plugged and abandoned as a dry hole.
The wave of drilling predicted last year in response
to higher oil prices and an increase in gas contract
availability appears to be occurring, with a mix of
exploration in both brownfields and greenfields
areas. While some of the greenfields exploration
results have been disappointing, for example the
Maginnis and Strumbo wells in the Browse Basin,
there is still a large amount of prospective acreage
that is largely unexplored by modern techniques and
play concepts. Perhaps the most exciting of the
upcoming greenfields exploration is the drilling of
the Sally May prospect (formerly known as the
WA Exploration Expenditure ($ million)
250
200
150
100
50
0
136.3
141.7
119.7
82
85.3
PWA April Edition - 2003 Review
Darren Ferdinando
Research Geologist, Resources Branch
Cetus prospect) in the central Canning Basin by
Kingsway Resources 2001 later this year. If
successful, this prospect has the potential to
completely rewrite current thinking on the Canning
Basin and introduce a number of new play targets
to the region. In the coming year a number of
critical wells are also planned for the onshore
northern Perth Basin, and success with these will
help push the boundary of the region deemed
prospective for liquid hydrocarbons further south.
This, in turn will help spur on further exploration in
the central Perth Basin region.
The Whicher Range 5 well, drilled in the southern
Perth Basin during the second half of the year,
proved to be a mixed result for Amity Oil. While
there is no question that there is a large gas
resource in the Whicher Range field, the extraction
of the gas from tight sandstone units affected by
170.2
191.5
151.3
177.9
Sep-01 Dec-01 Mar-02 Jun-02 Sep-02 Dec-02 Mar-03 Jun-03 Sep-03
Figure 1. Petroleum exploration expenditure in WA and % of total exploration expenditure in Australia.
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
7
Percentage of Australian Exploration Expenditure