What's new in exploration

	Vol. 226 No. 12
PERRY A. FISCHER, EDITOR

Barents Sea to become more open. Norway and Russia began negotiations to resolve a decades-old dispute over their maritime border in the Barents Sea. The 173,000-sq-km disputed area holds an estimated 12 billion bbl of oil equivalent. Further cooperation with regard to infrastructure could unlock other Barents resources estimated in the 40 billion boe range. Before activities were stopped in the 1970s due to the dispute, Russian seismic showed a huge geologic structure that, if filled, would hold almost four times as much gas as the 3.2-trillion-m³ (113 Tcf) Shtokman gas field – the largest offshore gas field in the world. So far, 80% of the disputed territory has been agreed to, but the last 20% could take awhile, although both countries say they are optimistic.

A Gazprom-led consortium is preparing to develop Shtokman, which lies 350 mi north of the Siberian coast and could cost between $10 billion and $25 billion. Majors, such as ConocoPhillips, Total and Chevron, as well as the main Norwegian companies, are interested. Statoil ASA and Chevron Norge AS have entered into an Area of Mutual Interest agreement regarding long-term cooperation for exploration in parts of the Barents Sea. The two companies have made a joint application in the 19th Norwegian licensing round.

New dating technique. The most accurate way to date oceanic crust has been discovered by scientists from the University of Wyoming, the United States Geological Survey and Woods Hole Oceanographic Institution. The technique advances the details of how oceanic crust is formed and the processes involved. The method increases the resolution of the date of crustal formation.

The key to the new technique was finding tiny zircon crystals in oceanic crust. “Uranium-Lead decay dating of zircon is widely regarded as the best technique for providing the absolute age of rocks on land,” according to Barbara E. John, a geology and geophysics professor and second author of a paper about the method that appeared in Nature.

The zircon dating technique has been used extensively to answer fundamental questions of age concerning Earth’s continental crust forms. Until now, magnetic “striping” was used to determine the age of the oceanic crust. After determining the striping patterns, an age would be calculated using distance and time between the magnetic polarity reversals revealed by the stripes. While the method works, it lacks the resolution to reveal all the complexity involved in the growth of ocean crust. One of the reasons zircon dating hasn’t been conducted previously is because some scientists believed that rocks in ocean crust do not contain zircon. In addition, it is difficult and expensive to retrieve rocks that are buried underwater at mid-ocean ridges.

With the aid of a $250,000 grant from the National Science Foundation, the scientists collected 17 zircon-bearing samples of lower oceanic crust from Atlantis Bank. Using a Sensitive High Resolution Ion Micro Probe to determine the absolute ages of 17 samples by the U-Pb zircon dating method, researchers found they could determine the absolute age of oceanic crust with an error of less than 1% of the age. Further, the scientists discovered that 25% of the samples they dated are up to 2.5 million years older than predicted by conventional models of crust generation at mid-ocean ridges.

Noteworthy discoveries. China says it has discovered a gas field and given a preliminary estimate of 3.5 Tcf in reserves. Called the Quigshen gas field, it is located about 88 mi west of the city of Daqing and “covers a vast area and has high-quality gas.” The field is “hidden in lava” beneath Daqing oil field. Xinhau news agency reported it as the country’s fifth largest gas field.

Iranian Oil Ministry announced the finding of a new field extension or compartment within the Mansouri oil field. The discovery holds an estimated 153 million bbl of recoverable oil, assuming a 20% recovery factor, and an additional 300 Bcf of recoverable gas. The field lies 275 mi southwest of Tehran.

Canada’s biggest offshore oil project, Hibernia, is reported to have a new compartment or field extension called South Hibernia. Although official information has been held tight, published rumors from “industry sources” are more than 300 million barrels (recoverable?). That would make overall recoverable reserves more than one billion barrels, well above the 615 million bbl when production started in 1997. Hibernia partners are ExxonMobil, Chevron, Petro-Canada, Murphy Oil, the government of Canada and Norsk Hydro. It is located 200 mi southeast of St. John’s, Newfoundland.

Victoria Oil & Gas made a discovery in Russia’s West Medvezhye field. A year ago, it acquired 74.8% of Russian firm ZAO SeverGas-Invest for $11 million, which owned the West Medvezhye gas-condensate exploration project in Russia. Estimates at the time of the sale were 4.7 Tcf of gas and 201 million bbl of recoverable gas condensate. The project forms part of the Western Siberian basin located in the Yamalo-Nenetsk Autonomous District, adjacent to the producing Medvezhye field and to the world’s largest gas field, Urengoy. The discovery has an estimated 500 Bcf of recoverable gas reserves.

Belize Natural Energy is operating two rigs and seems to have made the little country’s first commercial oil discovery, comprising high-quality crude. Photo courtesy of Belize Times.

Belize discovers oil! Somehow I missed this one, but last August, after years of fruitless petroleum exploration by international companies and 50 dry holes, a private local concern, Belize Natural Energy, and partners Aspect Energy and CHx LLC, announced that, since July 30, a well they drilled has been naturally flowing oil at a constant rate and pressure, producing about 500 bpd of 38° API gravity sweet light crude. The Belize Times further reports that as of November 10, the find is looking good. The company has secured 595,000 acres under a production sharing agreement. The Central American country is so small (pop. 200,000) that any commercial reservoir – even 100,000 bbl – will have a huge impact.