Carnarvon on track with Buffalo drilling ops in Timor Sea

Australia’s Carnarvon Energy has confirmed the drilling operations at its Buffalo-10 well, located offshore Timor-Leste, are progressing as scheduled.

In an update on Friday, Carnarvon advised that, since the last announcement on 6 January 2022, the 13 ³/₈” casing was cemented in place and the wellhead was installed.  The 12 ¼” hole section was then drilled down to a depth of approximately 2,707 metres measured depth (MD).

The Buffalo-10 well is being drilled offshore Timor-Leste within the TL- SO T19-14 Production Sharing Contract in a water depth of approximately 30 metres with a target depth of approximately 3,500 metres. Carnarvon is the operator of the licence and Advance Energy is its partner.

The well is being drilled using the Valaris JU-107 jack-up rig and the drilling operation started at the end of December 2021 after several months of delays.

In a separate statement on Friday, Advance said that the rig was setting and cementing the 9 ⁵/₈” casing before drilling ahead in the 8 ½” section hole to a planned depth of approximately 3,500 metres MD. For operational efficiency, the 9 ⁵/₈” casing is being set at approximately 2,700 metres MD, with the geological markers in the 12 ¼” hole section having been intersected within the pre-drill range.

Furthermore, the Elang reservoir is anticipated to be encountered in the 8 ½” hole section and wireline logs will be run over the Elang reservoir before determining if the well will be completed and suspended for potential future production.

Leslie Peterkin, CEO of Advance Energy, commented: “We are pleased with the progress reported by the operator, and the fact that we remain on prognosis is an encouraging indication that the geophysical interpretation is as we predicted. This bodes well as we prepare to drill ahead into the target Elang reservoir, and we look forward to offering further updates to the market in due course.”

The Buffalo-10 well is being drilled to test for the presence of commercial quantities of high-quality light oil that is expected to lead to the early re-development of the Buffalo field, which was discovered in 1996 by BHP and produced from 1999 to 2004.

The field resides in only 30 metres of water with a reservoir depth between 3,200 and 3,300 meters below the seabed. The previous field proved the existence of a very high deliverability reservoir containing high-quality light oil that is expected to sell at a premium to Brent in today’s market. The Buffalo-10 well will penetrate the existing oil column to assess the extent of the revised mapped attic oil column as the field was still producing when it was shut-in in 2004.

Carnarvon’s mid-case recoverable volume estimate is 31 million barrels (gross, 2C contingent resource). As the minimum economic field size is estimated to be significantly lower than the mid-case estimate, there is a strong likelihood that the Buffalo-10 well will confirm an economic project. In accordance with this, Carnarvon’s drilling plans provide for the Buffalo-10 well to be retained as the first production well in the redevelopment program.

To this end, Carnarvon and Advance are developing plans to compress the timeline to the first production once the Buffalo-10 well confirms a commercial oil resource. These plans include engaging with the industry for the supply and installation of suitable equipment to produce the oil.