Monterey shale oil eyed at Santa Barbara's Zaca field

Underground Energy Corp., Santa Barbara, Calif., will attempt to complete the Monterey shale at the Chamberlin 3-2 well on the 7,750-acre Chamberlin lease in its Zaca field extension project in Santa Barbara County, Calif.

The well, which went to a total depth of 7,685 ft for the budgeted $2.4 million, is a 300-ft offset to the Chamberlin 4-2, which discovered the Chamberlin East fault block but had mechanical problems. Chamberlin 3-2 encountered 1,700 ft of oil-saturated shale oil shows, including more than 1,200 ft of continuous Monterey oil shows in the deeper Chamberlin East fault block.

Logs confirmed that the oil saturation, fracture intensity, and formation thickness in the lower Monterey reservoir are consistent with the productive Monterey sections in the shallower fault block in the original Zaca oil field to the west. Zaca field wells typically had 1,100 ft of pay.

In the original Zaca field the 61 wells drilled on 10-acre spacing, including later infill wells, had average initial production rates in excess of 200 b/d and cumulative production of more than 540,000 bbl.

Underground Energy will move the Key 98 rig west to drill Chamberlin 2-2 to 4,350 ft into the shallower fault block of the Monterey shale before it releases the rig. That well will offset two Zaca field wells that have produced more than 500,000 bbl/well.

In view of the discovery of the Chamberlin East fault block and the potential of deeper structures that Underground has identified by seismic, the company is negotiating for a larger rig capable of more effectively drilling deeper. That rig is expected to arrive in 45-55 days.

Underground also signed a lease on 3,334 net acres that appear to have potential similar to the Zaca field extension project. The company owns 15,384 net acres at Zaca and a total of 70,000 net acres in California and Nevada.