Venoco to press Monterey shale work in 2010

Denver independent Venoco Inc. sees 2010 as the year it begins to exploit California’s Miocene Monterey shale in earnest and believes more than 10 billion bbl of original oil in place exist on its onshore acreage.

By OGJ editors
HOUSTON, Aug. 18
-- Denver independent Venoco Inc. sees 2010 as the year it begins to exploit California’s Miocene Monterey shale in earnest and believes more than 10 billion bbl of original oil in place exist on its onshore acreage.

The Monterey shale play is only now emerging, but the formation may hold the largest shale resource in the US with 300 billion bbl in place, said Timothy Marquez, Venoco chairman and chief executive officer. Monterey holds more than 2 billion bbl on its leases, Venoco estimated.

Venoco, which began geologic studies on the Monterey 4 years ago, has now amassed 200,000 prospective acres and is still leasing onshore. The package includes offshore leases held by production from other formations or not producing and nonproducing onshore acreage.

Venoco has drilled a couple of Monterey shale wells onshore and is pleased with the results, Marquez said without giving details.

At least 2,000 wells have been drilled and logged through Monterey in exploring and producing from deeper formations. Shale thickness ranges from 1,000 ft to 3,500 ft. The extremely complex reservoir is mostly a shale but with bits of most every other facies, Marquez said (see map, OGJ, Jan. 9, 1984, p. 75).

Venoco is “working toward completion techniques that can replicate the productive capacity” the company sees in the naturally fractured Monterey shale offshore and believes the shale holds oil that is lighter in gravity than typical California heavy oil.

Venoco has been producing from Monterey shale offshore for more than a decade in South Ellwood and Sockeye fields in the Santa Barbara Channel. South Ellwood’s production is entirely from Monterey, and Sockeye produces from Monterey and conventional formations.

Venoco is anxious to frac the Monterey at Sockeye, but no mobile frac equipment is available off California, Marquez said. The company hopes to access purpose-built frac equipment or bring it in from Alaska’s Cook Inlet by late 2009 or in 2010.

Marquez said the former ARCO Oil & Gas Co. discovered Monterey’s potential as a reservoir and not just a world class source rock when a well on South Ellwood’s Platform Holly developed a hole in the casing and flowed 1,500 b/d of oil.

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