Peter A. Craig1,
Tim J. Bourgeois1,
Terrell B. Stroud1
(1) Shell Offshore Inc, New Orleans, LA
Abstract: Planning, evaluation, and performance of horizontal wells at Ram-Powell
Ram-Powell is one of the major tension leg platform (TLP) developments in the eastern deepwater Gulf of Mexico. There are three main turbidite reservoirs currently under development producing from a total of five horizontal open-hole gravel-packed wells. The high rate and high ultimate recovery from these horizontal wells has substantially reduced the development well count (in one reservoir by 80%). A-3ST1 held a GOM record of highest rate for a single well: 40,900 BEQ per day.
Understanding reservoir architecture is key to execution of a trajectory plan. This knowledge is best obtained through use of pilot wells near the horizontal well path. In using exploratory or appraisal wells as pilots, survey accuracy can be critical to success. Horizontal well trajectories can be optimized in reservoirs (such as levees or sheet sands) in which lateral variations are well understood. At Ram-Powell, horizontal wells in these depositional systems were drilled oblique to strike, so as to transect the entire section. In more laterally variable systems, such as channels, more well control or geosteering is required.
New applications of petrophysical tools, unique to horizontal wells, aided in drilling and reservoir analysis. Density images from a 4-” OD LWD density tool were used to calculate the dip of the thin-bedded L sand. This tool was also used to evaluate the geometry of calcite-cemented zones in an unconsolidated sand. Quantitative Fluorescence Technique (QFT) quantifies the fluorescence in cuttings for pay evaluation. Measurements were used to distinguish mudstone, thin-bedded sand, and massive sand.
AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana