Slimhole Exploration Requires Proper Technical Preparation

Abstract

Abstract Any application of new technology requires proper preparation to ensure a safe and efficient field program. Slim hole technology requires different preparation and procedures than conventional rotary drilling techniques. Application of the mining industry’s coring techniques, small wellbore annuli, precise fluid flow measurement for kick detection, and specialized drilling fluids requires significant technical understanding and preparation. For Mobil in 1991, to prepare for a first application of Slim Hole Drilling Technology, the preparations included drilling a test well with Longyear Company’s Oil and Gas Division at Mobil’s Dallas Research Lab and using the information to prepare for two slim hole oil and gas exploration wells to be drilled in Bolivia, South America. The test well gave Mobil drilling personnel practical hands on experience with the technology and provided a slim hole test laboratory to perform extensive borehole hydraulics tests and practice well control techniques. The information gained from the test well was used to plan two exploration wells in the Madre De Dios Block in Northern Bolivia. Industry has proven the economic advantages of utilizing this emerging new technology for Oil and Gas Exploration, especially in the remote frontier areas of the world. The planning, technical, and operational points of interest are highlighted in the paper. The advantages and disadvantages of the technology observed during the wells are illustrated. Methods available to allow the technology to adapt to Oil and Gas and API standards are discussed. Many technical aspects of the application of the technology are discussed which will give an insight to the minimum technical preparation a company needs to perform to be comfortable with a first application. Areas of technology are highlighted where additional development of the technology is needed.