Published April 2010

Well drilling experience in Baku and Absheron archipelago fields complicated conditions

Sh.Kh.Bekirov

Oil and gas bearing horizons of Baku and Absheron archipelago are located in Productive Series. They are formed by the terrigenous sediments of Pliocene age and in terms of lithology consist of clays, sand and sandstones. Frequent losses of circulation and pipe stick accidents occurring while well drilling in the fields of Baku and Apsheron archipelago. Thus, analysis of experience in well drilling in these fields is very interesting. Experience of drilling well No759 from the fixed platform No578 at 8th March field, which is located in Baku archipelago and was drilled with the author’s participation, is described in this article. This well was drilled using pressure control approach. Data presented in the article show that drilling of well No759 was accompanied by complications due to the presence of abnormally high formation pressure and temperature and repeated accidents. Using innovative design and modern technology (pressure control method, hydraulic underreamers, bis-essentic bits, drilling with simultaneous underreamers of the hole, development and use of effective engineering solutions in drilling operations, development and use of efficient wells completion) well was drilled and completed, successfully tested and commissioned. For subsequent successful drilling, accumulation and analysis of geological-geophysical, engineering data is required, forecasting of zones with abnormally high formation pressure and temperature analysis and assessments of risks in the course of drilling as well as analysis of various existing methods of accidents prevention accounting for specific geological section and development of most efficient methods.