Roc Spuds Another Sidetrack from Beibu Discovery

Roc Oil Co. Limited

Roc Oil Co. Limited reported that it spudded a second sidetrack, Wei-6-12S-1Sb, last Thursday from its Wei-6-12S-1 oil discovery in Block 22/12, Beibu Gulf, offshore China.

At 6 a.m. local time on Wednesday, the second sidetrack had been drilled to a depth of 2,217 meters below Rotary Table (mBRT) and was at a lateral distance of about 300 meters from the original well and approximately 50 meters vertically downdip from equivalent horizons in that well.

The current operation is drilling ahead in the main reservoir section, the Weizhou Formation, toward a proposed total depth of 2,849 mBRT.

The second sidetrack is a relatively aggressive step-out to the southwest of the original discovery well. It is designed to intersect a number of the reservoir intervals downdip from the original discovery well. The reservoir equivalents of the original well, which the company expects will be encountered in the lower part of the second sidetrack, are likely to be water-bearing because they are a considerable distance downdip. Nevertheless, the hope is that the second sidetrack will encounter one or more downdip oil legs in the higher part of the Weizhou Formation.

The second sidetrack has an exploration element that will target a specific sand not present in the original well but may possibly be present toward the bottom of the second sidetrack.

The detailed outcome of the drilling will not be known until next week, when the second sidetrack is expected to have been logged at total depth.

The Block 22/12 joint venture comprises:

--Roc Oil (China) Co. (40%, operator)
--Horizon Oil Limited (30%)
--Petsec Energy Ltd (25%)
--Oil Australia Pty Ltd (a unit of First Australian Resources) (5%)

Pending a commercial development within the block, the China National Offshore Oil Co. (CNOOC) is entitled to participate up to a 51% funding equity level.