2003 yields 17 deepwater GoM discoveries

Jan. 1, 2004
Independents and supermajors drilled, and the hydrocarbons showed up � in 17 discov- eries in the deepwater Gulf of Mexico.

Operators plan development, more drilling

Jennifer Pallanich Hull
Gulf of Mexico Editor

Independents and supermajors drilled, and the hydrocarbons showed up – in 17 discoveries in the deepwater Gulf of Mexico.

Click here to view Gulf of Mexico discoveries and status.

From January to November, operators posted finds with Atlas, Chinook, Constitution, Ewing Bank 1006, Goose, Harrier, Jubilee, Lorien, Medusa North, Perseus, Raptor, South Dorado, Spiderman, St. Malo, Sturgis, Tomahawk, and Tubular Bells. Most of the finds are under evaluation, although the respective operators have said Atlas, Ewing Bank 1006, Goose, Jubilee, Medusa North, and Spider-man will be subsea projects if they are developed. Pioneer's Harrier, Raptor, and Toma- hawk subsea projects – all part of the Falcon Corridor – are in development, and Harrier was expected to be onstream in late 2003.

Anadarko and Pioneer each posted three discoveries. BP and ChevronTexaco had two each. BHP Billiton, Kerr-McGee, Spinnaker, ConocoPhillips, Murphy, Unocal, and Walter each reported single finds.

Water depths for discoveries in 2003 ranged from 1,548 ft for Spinnaker's Goose to 9,000 ft for Anadarko's Atlas. In 2002, operators reported 21 discoveries.

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    Discoveries reported in 2003: 1 – Atlas, 2 – Chinook, 3 – Constitution/Hornet, 4 Ewing Bank 1006, 5 – Goose, 6 – Harrier, 7 – Jubilee, 8 – Lorien, 9 – Medusa North, 10 – Perseus, 11 – Raptor, 12 – South Dorado, 13 – Spiderman, 14 – St. Malo, 15 – Sturgis, 16 – Tomahawk, and 17 – Tubular Bells. Fields brought onstream in 2003: A – Boris, B – Falcon, C – King West, D – Matterhorn, E – Mississippi Canyon 837, F – Northwest Navajo, G – West Navajo, H – Ochre, and I – Zia.

Making plans

Anadarko is considering a hub facility to handle its Atlas, Jubilee, and Spiderman finds in the Eastern Gulf of Mexico. Anadarko said its Atlas discovery well at Lloyd Ridge block 50 in nearly 9,000 ft of water encountered 180 ft of gross pay. Anadarko planned a sidetrack wellbore to obtain conventional core samples in late 2003. Anadarko holds 100% interest in the Atlas discovery.

The Jubilee find at Atwater Valley block 349 is in 8,800 ft of water. The discovery well found 83 ft of net pay. Operator Anadarko holds 100% interest in the field and is also evaluating its Spiderman find on DeSoto Canyon block 621 in 8,100 ft of water. The discovery well encountered more than 140 ft of net pay in its two primary targets. Operator Anadarko holds 45%, Dominion 36.7%, and Spinnaker Exploration 18.3%.

BHP Billiton is looking for more appraisal data before it decides the future of the Chinook find on Walker Ridge block 469, where the exploratory well encountered a 620-ft gross column of hydrocarbons with 260 ft of net oil pay. The well, in 8,830 ft of water, was temporarily abandoned for future use. Operator BHP has 40%, Petrobras 30%, and Total and Amerada Hess 15% each.

Kerr-McGee is defining the extent of the reservoir at its Constitution and Hornet discovery after encountering a combined total of nearly 500 ft of net pay in the two wells. The initial Constitution well encountered over 100 ft of net pay, and the second well encountered 375 net ft of pay. The Hornet appraisal well encountered more than 275 ft of net pay and is being sidetracked 2,300 ft to the northwest to define the extent of the reservoirs. Constitution is in 5,000 ft of water on Green Canyon block 680, and Hornet is in 3,850 ft of water on Green Canyon block 379. Kerr-McGee holds 100% interest in both fields.

The Ewing Bank 1006 discovery is a new find on a field on which Walter Oil and Gas has previously reported discoveries and production. This subsea project in 1,854 ft of water is under development.

Spinnaker has been evaluating tie-back possibilities for its Goose discovery at Mississippi Canyon block 751, in 1,600 ft of water. The exploratory well found 110 ft gross of hydrocarbon pay. Operator Spinnaker holds 100% working interest.

Pioneer's Falcon Corridor is under development. The indy's latest finds will be tied back to Falcon Nest, where the company brought Falcon onstream in March 2003 and planned to bring Harrier onstream in December. Pioneer was also working to bring Raptor and Tomahawk onstream in mid 2004 as subsea tiebacks to the Falcon Nest platform, operated by El Paso. Harrier, on East Breaks block 759 in 3,600 ft of water, holds estimated gas reserves of 55 bcf-80 bcf. Operator Pioneer holds 100% interest in the fields.

ConocoPhillips suspended its Lorien exploration well on Green Canyon block 199. Drilled in 2,177 ft of water, the well encountered more than 120 ft of pay. ConocoPhillips is appraising the hydrocarbon zone. Operator ConocoPhillips holds 65%, Noble Energy Inc. 20%, Norsk Hydro E&P Americas AS Inc. 10%, and Davis Offshore L.P. 5%.

ChevronTexaco plans appraisal work at its Perseus discovery at Viosca Knoll block 830 in 3,376 ft water depth. Operator ChevronTexaco holds 50% interest, and Marathon holds the remaining interest. The discovery well encountered 166 net ft of oil pay, and partners planned to evaluate development options that would bring the discovery onstream in 2005. Production would be sent 5 mi away to the existing Petronius platform.

The exploratory well at the Unocal-operated St. Malo find on Walker Ridge block 678, lo-cated in 6,900 ft of water, found more than 450 net ft of oil pay over a gross interval of 1,400 ft. Unocal holds 28.75%, Petrobras 25%, Devon 22.5%, ChevronTexaco 12.5%, EnCana 6.25%, ExxonMobil 3.75%, and Eni Petroleum 1.25%.

ChevronTexaco will appraise its Sturgis discovery after the exploratory well on Atwater Valley block 183 in 3,700 ft of water found more than 100 ft of net pay sands. Operator ChevronTexaco holds 50% working interest, and Devon and EnCana each hold 25% working interest.

BP said it plans further appraisal drilling at its Tubular Bells find on Mississippi Canyon block 725 in 4,300 ft of water. The exploratory well encountered 190 ft of net oil pay. Operator BP holds 50%, ChevronTexaco 30%, and Amerada Hess 20%.

Murphy operates the Medusa North discovery on Mississippi Canyon block 538 in 2,185 ft of water. It is just north of Mississippi Canyon block 582, where the Medusa spar went onstream in 2002.

BP's South Dorado discovery is on Viosca Knoll block 915 in 3,494 ft of water. It is under development.

Going onstream

In 2003 the Boris, Falcon, Gunnison, Hab-anero, King West, Matterhorn, Mississippi Canyon 837, Northwest Navajo, West Navajo, Ochre, and Zia fields went onstream. Of these, Kerr-McGee operated two, and BHP Billiton, BP, Devon, Mariner Energy, Pioneer, Total, and Walter operated one each. Water depths for the nine fields that went onstream in 2003 ranged from 1,144 ft for Mariner's Ochre to 5,4300 ft for BP's King West. Total developed Matterhorn with a TLP, while the rest were subsea. Harrier, discovered early in 2003, was expected to be onstream in late 2003. In 2002, 17 fields went onstream.

At the end of 2003, 29 fields were under development: Atlantis, Devils Tower, Durango, Front Runner, Gunnison, Habanero, Harrier, Holstein, K2, Llano, Mad Dog, Magnolia, Mar-co Polo, the Na Kika complex, Princess, Quatrain, Raptor, Red Hawk, South Dorado, Thunder Horse, and Tomahawk.