Bass Oil Hits 2,400 bopd at Bunian 6 With New Pay Zone Set to Triple Output
Key Takeaways
- The Bunian 6 well flowed at 2,400 bopd on a one-hour clean-up test from the M sand — a zone with no prior production history in the Bunian field — with zero water cut across both flow tests.
- Bass Oil expects field production to triple from 250 bopd to at least 750 bopd (100% JV basis), lifting Bass's own net share from 140 bopd to at least 410 bopd once the flowline tie-in is complete.
- The M sand is the primary producing zone at the adjacent Tangai oil field, providing a commercially proven analogue that lends confidence to the new discovery's potential.
- The well was completed across three separate pay zones — TRM3, K1, and M — with TRM3 alone carrying an internal P50 recovery estimate of 151,000 barrels on a 100% JV basis.
- Bass Oil is debt free, meaning production growth from Bunian 6 flows directly to cash generation, with further drill targets at Bunian West and Bunian North West already identified in the integrated field study.
Bunian 6 delivers M sand oil discovery with 2,400 bopd clean-up flow rate
Bass Oil Limited (ASX:BAS) has confirmed a new oil discovery in the M sand at the Bunian 6 well in Indonesia, with the zone flowing at approximately 2,400 barrels of oil per day (bopd) on a one-hour clean-up flow. The result has exceeded pre-drill expectations and confirmed oil pay across three separate reservoir zones.
The M sand clean-up test was conducted on a 23.9mm choke, recovering 100 barrels of oil with zero water cut at a flowing wellhead pressure fluctuating between 210 psi and 395 psi. After shut-in, a pressure of 560 psi was recorded after 30 minutes — a signal of reservoir energy remaining in the zone.
A follow-up flow test on the M zone produced 1,264 bopd over a three-hour period on a reduced 10.5mm choke at a flowing pressure of 415 psi, recovering an additional 158 barrels of oil with no water. The well was then shut in to observe pressure build-up.
The rig completed the well as an oil producer from all three pay zones — the TRM3, K1, and M reservoirs — and was released at 4pm local time on 7 September 2026. The completion was configured to test and produce each zone separately, commencing with the M zone.
The zero water cut result across both flow tests is a meaningful quality indicator. Water production is a common complication in mature oil fields, and its absence here suggests the well is accessing clean, uncontaminated oil.
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Production set to triple as well completion targets 750 bopd output
The Bunian 6 result is expected to deliver a significant step-change in Bass Oil’s Indonesian production. The production uplift expected from this well:
- Current field production: 250 bopd (100% JV share)
- Expected post-Bunian 6 production: at least 750 bopd (100% JV share)
- Bass Oil’s current share (55% interest): 140 bopd
- Bass Oil’s expected share: at least 410 bopd
A production test programme is now underway to confirm reservoir parameters across all three zones and to determine which zone will be brought onto production first. The flowline tie-in to the production facility is expected to be completed shortly after the rig moves off location.
Managing Director Tino Guglielmo
“The Bunian 6 well result has exceeded our pre-drill expectations. The oil pay identified in the highly productive M sand is a welcome bonus and will increase field oil recoveries. This result offers Bass significant production growth at a time of high oil prices. This is the first success in a diversified program of projects underway that aim to establish Bass as a profitable mid-tier energy company.”
What is an M sand oil discovery — and why does it matter for investors?
To understand why this result is significant, it helps to know what “M sand” refers to and what the testing process establishes.
M sand is a sandstone reservoir zone found at a specific geological depth within the Bunian field structure. It was identified in Bunian 6 via wireline logging and mud logs during drilling. Critically, oil pay in the M sand has not previously been intersected or produced in the Bunian field — this is a genuinely new pay zone for the field. However, the M sand is the primary producing zone at the adjacent Tangai oil field, which provides an established analogue and lends commercial confidence to what Bass has found.
Clean-up flow testing is the initial phase of well evaluation after drilling. When a well is first opened to flow, drilling fluid and other materials need to clear the wellbore before the well can produce naturally. The flow rate measured during this phase gives an early indication of the zone’s productivity, though it is not the same as a sustained production rate.
The three reservoir zones confirmed in Bunian 6, and their planned production sequence, are:
- TRM3 — the primary objective, with an initial production forecast of 500 bopd. Internal modelling estimates an ultimate recovery of 151,000 barrels (P50, 100% JV basis) from this zone alone. This estimate is based on internal modelling and performance of nearby wells — it does not yet incorporate the M sand, whose reserve potential remains to be quantified following further analysis.
- K1 — the second zone, to be produced sequentially after TRM3.
- M — the newly discovered zone, to be tested and produced separately. The M sand is where the most significant upside resides, given it is a new discovery for the field.
Further drill targets identified in the integrated field study include Bunian West and Bunian North West, suggesting the current result may be the first of several wells in this structure.
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Bass Oil’s broader growth strategy comes into focus
Bunian 6 is described by management as “the first success in a diversified program of projects” aimed at establishing Bass as a profitable mid-tier energy company. The well result sits within a broader asset base that spans two countries and multiple production and development assets.
| Asset | Location | Bass Interest | Status | Near-Term Catalyst |
|---|---|---|---|---|
| Tangai-Sukananti KSO (incl. Bunian 6) | South Sumatra, Indonesia | 55% (Operator) | Producing | Production test underway; flowline tie-in pending |
| Worrior oil field | Cooper Basin, Australia | 100% | Producing | — |
| Padulla oil field | Cooper Basin, Australia | 100% | Producing | — |
| East Coast Gas projects (three projects) | Australia | Majority interest | Development | Australian East Coast Gas Market entry targeted late 2026 |
The joint venture partner in the Indonesian KSO is Mega Adhyaksa Pratama Sukananti Ltd (MAPS), which holds the remaining 45% interest.
What the Bunian 6 result demonstrates is that Bass’s Indonesian asset has material upside beyond what was already in the production profile. A tripling of field output — if the production test programme confirms reservoir parameters — would substantially change the company’s earnings trajectory. The company is currently debt free, which means production growth flows directly to cash generation rather than debt service. With oil prices elevated, the timing of this result adds further commercial weight to what is, on the early data, a technically clean and high-rate discovery.
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