Nexus Ups Best Estimate for Crux

Nexus Energy Ltd has increased the best estimate contingent resource at the Crux Field in the Browse basin to 65 million barrels, an increase from the previous contingent resource estimate of 55 million barrels released on 15 March 2007.

The increased estimate incorporates the results of the successful Crux-2 ST1 well completed recently.

The increase in contingent resource liquids volumes results from the higher than expected "Condensate to Gas Ratio" encountered in the sidetrack well.

The discovery of the highly productive Plover Formation has also increased the likelihood of higher than expected gas volumes in the field.

The new contingent resource liquids volumes together with the volumes calculated before the drilling of the Crux-2 ST1 well are shown in the table below.


Contingent Resource Confidence	      Low  Best   High 
Condensate (MMstb) @ 15 March 2007    40   55     71
Condensate (MMstb) @ 7 May 2007       45   65     85

This increase in contingent resource volumes can be attributed to two factors:

  • Increase in Condensate Gas Ratio ("CGR") – reservoir gas sampling from Crux-2 and the Crux-2 ST1 well confirm a significant increase in condensate gas ratio which has had a direct impact on liquids resources. CGR for the field is now estimated to be 35 barrels of condensate per million standard cubic feet of reservoir gas, an increase of 13% above the previous CGR used to calculate resources after the drilling of Crux-2.
  • Increase in gas reservoir section - Crux-2 ST1 has confirmed that the high quality Plover Formation sand seen in the Crux-2 well is present over the north eastern part of the Crux Field and has the potential to add significant additional further resources in the high case. No contingent resources were previously attributed to this younger reservoir section.

The above volumes only include that part of the Crux Field within the AC/P23 exploration permit. Additional resource potential exists to the southwest, where the Crux structure is mapped to extend into the AC/P41 exploration permit, where Nexus holds an interest of 50%.

Nexus Managing Director, Ian Tchacos said:

"Nexus is particularly pleased that the side track well results have confirmed an increased liquids content and the large intersection of the A sand as predicted, together with an additional younger reservoir sand section. The combination of these results has had a significant impact on contingent resource condensate estimates compared to those released after Crux-2.

"The increased liquids content of the gas will also have a favorable impact on recycle project production rates and resultant field economics. It is anticipated that a plateau production rate of 32,500 barrels per day can be achieved for the basis of design recycle rate of 900 MMscf/d."

Nexus Energy WA Pty Ltd is the sole participant in the permit. The Crux Field is located in AC/P23 in the offshore Browse Basin, Western Australia.

For More Information on the Offshore Rig Fleet:
RigLogix can provide the information that you need about the offshore rig fleet, whether you need utilization and industry trends or detailed reports on future rig contracts. Subscribing to RigLogix will allow you to access dozens of prebuilt reports and build your own custom reports using hundreds of available data columns. For more information about a RigLogix subscription, visit