The huge Trident discovery in the Gulf of Mexico is particularly interesting to Mexico: 20% of the structure is in its part of the Gulf, according to Alfredo Guzman, exploration strategies coordinator for Pemex E&P. Unocal Corp., the operator, found more than 300 feet of hydrocarbon-bearing pay and additional interesting zones this summer when drilling the first Trident exploratory well, in Alaminos Canyon Block 903 in nearly 10,000 feet of water. Guzman made the statement while addressing Houston Geological Society members recently. Christine LeLaurin, Unocal spokesman, says the project's staff members realize some of the structure that has been tapped into may be partially on Mexico's side of the Gulf. "We've drilled just one well, so a lot is unknown. We will start our first appraisal well later this month and will know more about the structure then," LeLaurin says. The 20,500-total-depth exploratory well is about 185 miles southeast of Corpus Christi. The oil that was found has a gravity of better than 40 degrees. The Trident structure appears to be nearly 10,000 acres, covering seven blocks, according to Unocal. There is no word on whether Pemex gets 20% of the bill for the exploratory well's $34-million gross cost-or for its share of development costs. Unocal is currently evaluating commerciality. It has a 59.5% working interest in the prospect; Chevron U.S.A. Production Co., 15%; Ocean Energy Inc., 12.75%; Agip Petroleum Co., 8.55%; and Phillips Petroleum Inc., 4.2%. Houston-based FMC Technologies Inc. says it is presently developing subsea-system technology for production in 10,000 feet of water. The technology should be ready by year-end 2002. The company has systems presently for production in up to 7,500 feet of water. As explorationists drill farther from the U.S. shore and nearer to Mexico's, "both countries recognize the possibility a transboundary oil and gas reservoir may exist," the MMS reported when announcing the U.S. Mexico maritime boundary agreement last year. Meanwhile, Mexico's constitution presently prohibits non-national ownership of oil and gas reserves on its soil.