JOHANNESBURG (miningweekly.com) - ASX-listed Australia Bass Oil on Monday announced a major upgrade to the prospectivity of the company's producing Tangai-Sukananti KSO, located in onshore Sumatra, Indonesia.
Highlights of the upgrade, resulting from an independent review of the company's stake in the KSO located in the prolific oil production province in southern Sumatra, include an additional 1.6-million barrels of low-cost, unrisked, prospective oil resources, in two new near-field targets.
As a result of the study's findings, Bass immediately added these new targets to its planned 2018/19 drilling programme.
Bass Oil commissioned the review during 2017, following its acquisition of a 55% stake in the licence, which includes the current producing Bunian and Tangai oilfields.
Further, Bass has successfully defined two exploration prospects in addition to the existing known fields. Both prospects target oil potential at multiple reservoir levels within the prolific Talang Akar Formation, which contains the oil producing reservoirs in the existing Bunian and Tangai fields.
The Sukananti Updip prospect lies south of the Bunian oilfield. Sukananti-1, drilled in 1996, intersected a 2-metre-thick oil-filled sand at the TRM2SS reservoir level, which has significant up-dip potential on the southern flank of the Bunian field.
Additionally, three other oil-bearing reservoirs in the Bunian field, are not within a trapping configuration at the Sukananti-1 location, but do form attractive targets at the Sukananti Updip location, the company added.
For the combined reservoirs, the Sukananti Updip prospect has 1.28-million barrels of oil on an unrisked, prospective, recoverable, best estimate basis with a 30% chance of geological success. Sukananti Updip has a high estimate upside of 3.16-million barrels of oil on an unrisked, prospective, recoverable basis.
The Bunian West prospect is a faulted, anticlinal closure to the west of the Bunian oilfield. The prospect has the potential for oil and gas at five stacked reservoir levels all proven to be effective in the KSO.
For the combined reservoirs, the Bunian West prospect has 0.35-million barrels of oil on an unrisked, prospective, recoverable, best estimate basis with a 32% chance of geological success.
Bunian West has a high estimate upside of 0.81-million barrels of oil on an unrisked, prospective, recoverable, best estimate basis.
The Bunian West and Sukananti Updip prospects are fully defined by the 2011 Sukananti three-dimensional seismic survey data which was comprehensively reprocessed in 2014.
Following approval by the Indonesian government authorities, the company noted that the prospects will be included in Bass Oil's 2018/19 drilling and development programme for the KSO.
Once approved by the regulator, the drilling costs of both wells will be fully cost recoverable against existing production under the terms of the KSO. Joint venture participants in the KSO are Bass Oil (Operator 55%) and Mega Adhyaksa Pratama Sukananto (45%).