Applications of Oil-base Mud Earth Imager for a High-temperature and High-pressure Exploration Well
Robert Maddock, Rodmar Ravnas, 2010. "Applications of Oil-base Mud Earth Imager for a High-temperature and High-pressure Exploration Well", Dipmeter and Borehole Image Log Technology, M. Pöppelreiter, C. García-Carballido, M. Kraaijveld
Download citation file:
An exploration well was drilled as a wildcat targeting high-pressure and high-temperature gas condensates within Jurassic-age reservoir sandstones offshore Norway. The well, drilled to a depth of more than 5000 m (16,404 ft) subsea with bottom-hole temperatures up to 176 °C and mud pressures up to 93 MPa, was successfully tested. As part of a comprehensive logging and coring program, oil-base mud EARTH Imager℠, Baker Hughes/Baker Atlas data were acquired in the discovery well. The objectives of the wellbore imaging were to determine the structural dip, confirm the presence or absence of (seismic and subseismic) faults, support detailed core sedimentology studies, and determine the orientations of depositional or architectural elements. This contribution summarizes the acquisition and interpretation of the borehole images. Structural dip and an apparent low density of faulting interpreted from the images were consistent with the predrill structural interpretation. Comparison of the core and images assisted in the characterization and orientation of the depositional architecture.
Figures & Tables
Borehole imaging is among the fastest and most accurate methods for collecting high resolution subsurface data. Recent breakthroughs in acquisition, tool design, and modeling software provide real-time subsurface images of incredible detail, from the drill bit straight to a workstation. Associated interpretation workflows offer the high level of detail that is needed to make operational decision and to increase the predictability of subsurface models. Many exploration and production companies have acquired a wealth of dipmeter and image log data. The data are readily available and provide, for example the orientation of fractures and fluvial channels in space. Further applications of borehole imaging technology include matrix and fracture characterization, pore-type partitioning, geosteering, and in-situ stress determination. Exciting new applications are found in enhanced oil recovery, carbon dioxide sequestration, and geothermal projects. In addition, borehole image data are paramount to unlocking unconventional plays such as shale gas and coal-bed methane. AAPG Memoir 92 portrays key applications of dipmeter and image log data across the exploration and production life cycle. (Continued)