This is to call your attention to an outstanding article entitled "SW Siberia's Jurassic, Bazhenov" by Linberger and others that appeared in Oil & Gas Journal, May 22, 2000. Largely on a basis of seismic and drilling data they delineate areas favorable for significant Jurassic oil discoveries. This is one more stage in the assessment of this highly potential mega-play. Our attention became focused on the Upper Jurassic Bazhenov Formation of West Siberia when the Soviets set off a nuclear devise in Salym oil field on October 4, 1979 (Clarke and Rachlin, Oil & Gas Journal, June 16, 1980). We realized that they were attempting to stimulate oil flow in the black bituminous cherty shale of the Bazhenov Formation, which tops off the Jurassic of central West Siberia. In that paper we mentioned an estimate that the oil-in-place of the Bazhenov was 2,000 billion tons (14,000 BBO) - this over a total area of more than a million sq km. Some Swedish group then reported this to the press as a discovery, and for several hours oil stocks underwent extreme swings. I was in the field in South Carolina that day, and Chuck Masters handled the situation in a masterful manner. Much has been published in recent years on the Jurassic of West Siberia. Transgressive-regressive cycles have yielded a succession of source beds (seals) and sandstone reservoirs. See Petroleum Geology, vol. 33, no. 3, p. 228; vol. 34, no. 1, p. 10; vol. 34, no. 2, p. 178; and others. The May 22 Oil & Gas Journal article assesses total oil resources of the Jurassic of West Siberia using a volume method. Porosity and permeability are attributed to fractures, presence of which is indicated by loss of circulation and by oil and gas shows during drilling. Open fractures are also indicated by overpressure. The area where overpressure is significant is estimated at 15,600 sq km and may be as much as 37,500 sq km. Thickness of this overpressured zone is placed at more than 400 m. On this basis the oil resources of the Jurassic of West Siberia are assessed at 9 billion tons (63 BBO). If area of pay and other parameters are greater, this figure increases 2-3 times to 20-30 billion tons (140-210 BBO). In my opinion most of the Jurassic oil of West Siberia is present in sandstone reservoirs. If this be true, then the total oil endowment of this vast region the size of the United States east of the Mississippi is almost beyond comprehension. Copyright 2000 James Clarke. You are encouraged to print out this News Letter and to forward it to others. Earlier News Letters are available at http://geocities.com/internetgeology For information on Petroleum Geology, please contact at (703) 759-4487.