Tap Oil IDs O&G at Brunei Well

Tap Oil provided the following information on the Mawar-1 exploration well in Block M, onshore Brunei Darussalam. Preliminary interpretation of wireline, pressure and sampling data suggests gas has been encountered in the primary Ridan objective while oil is indicated by data at deeper levels.


Mawar-1 has reached its total depth of 1,292m MD and wireline logging, pressure and fluid sampling has now been completed. Casing is currently being run across the hydrocarbon zones prior to suspending Mawar-1.


Preliminary interpretation of these results indicates that Mawar-1 has encountered gas in primary objective Ridan Sandstone. Preliminary log analysis suggests Mawar-1 has encountered up to 25 metres of Ridan reservoir at a depth of 1,005m MD. The presence of gas in this interval is indicated by pressure analysis and sampling. The thickness and quality of the Ridan Sandstone is poorer than expected pre-drill.

A deeper secondary objective Rampayoh Series also had good hydrocarbon indications in cuttings and sidewall cores in an inter-bedded sand-shale sequence. Fluid samples have been taken at 1040 m MD and 1048.6 m MD. These samples remain sealed for laboratory analysis but indications are that they contain oil. Reservoir quality in the upper part of the Rampayoh Series is unclear and will only be confirmed with further analysis of the well data. Once the analysis of all the data has been completed Tap will be able issue more definitive statement regarding the potential of the Mawar-1 well.

Tap Comment

Tap Chief Executive Officer, Peter Stickland, said Mawar-1 had yielded mixed results.

"We are disappointed that the primary objective Ridan formation appears to be gas charged at this location. Further studies will be undertaken to determine if there is potential for an oil leg down dip of the gas in Mawar-1," Mr Stickland said.

"We are however pleasantly surprised by the oil indications from the deeper Rampayoh Series. This was an unexpected result but further investigation will be needed to determine if this has commercial potential in Mawar-1 and also its implications along the Belait trend."

"Mawar-1 will now be suspended, before relocating the rig to the nearby Markisa-1 location, which will be testing the oil potential in a younger reservoir in a separate fault compartment of the Belait Anticline."


Block M covers an area of approximately 3,011 km2 (see attached map) in the Baram Delta Basin and is the largest onshore permit in Brunei. The Block contains the Belait oil and gas field, but is under-explored having not seen a concerted exploration effort during the past 20 years.

Block M Participants:

  • Tap Energy (Borneo) Pty Ltd 39%
  • Triton Borneo Limited 36%
  • China Sino Oil Company Limited 21%
  • Jana Corp. Sdn. Bhd. 4%