InterOil Begins Logging Antelope-1 Well

InterOil has successfully drilled 2,041 feet (622 meters) into the Antelope reservoir, following the confirmation of gas and condensate at the top of the reef announced on December 31, 2008. The top of the reservoir was intersected at 5,735 feet (1,748 meters). Drilling continued from 5,738 feet (1,749 meters) to 5,837 feet (1,779 meters) with an under-balanced system. At 5,837 feet (1,779 meters) total losses were experienced and forced the change to a mud cap system.


  • First dolomite was seen at 5,689 feet, with reefal shallow marine facies encountered until total losses of drilling mud and cuttings at surface.
  • The dolomitized facies had 'good to very good' visible matrix and vugular porosity observed in the cuttings 5,735 feet (1,748 meters) to 5,837 feet (1,779 meters) during under-balanced drilling operations.
  • The permeability has been exceptional with total loss to the formation of over 73,000 bbls of drilling fluid and all cuttings below 5,837 feet (1,779 meters). The well has remained clean with no indications of cuttings build up or bridging despite very good penetration rates.

The forward program is to log the well, core the lower section from 7,776 feet (2,370 meters) to 7,953 feet (2,424 meters) in order to acquire reservoir data and to evaluate the heavy condensate seen at Elk-4. Once coring operations are complete, the plan is to drill ahead conventionally to approximately 8,200 feet (2,500 meters) and test and fully evaluate the well.