A decade of drilling developments pays off in offshore Italian oil field

As the only oil field in the world producing systematically through horizontal wells, Rospo Mare, the Italian oil field in the Adriatic, is s ''first.'' Rospo Mare is an uncommon oil field because the nature of its reservoir and the characteristics of its oil prevent it from being produced through conventional vertical wells. But thanks to horizontal drilling techniques developed since 1977 by Elf Aquitaine and the Institut Francaise du Petrole (IFP), the field was producing 22,00 b/d of crude oil on Jan. 1, 1988. Of this, 19,000 b/d came from six horizontal wells and 3,000 b/d from three vertical or deviated wells. For comparison, on Jan. 1, 1987, the field produced only 4,300 b/d through a single horizontal well, two vertical wells, and one deviated well. Rospo Mare is a joint venture of Elf Italiana (61.7%), the operator, and AGIP (38.3%). A description in this article of the challenge of Rospo Mare and the results to date set the stage for a series of articles in coming weeks. They will cover the state of the art in not only drilling, but horizontal completions, production, log interpretation, and other aspects of this major oil industry technology.