The technical presentation “A Comprehensive Approach to Optimize Completions Design for Conglomerates and Fractured and Weathered Basement Reservoir Rocks” will be given by Sayyid Ahmed from Halliburton.
Abstract:
Triassic conglomerates and basement rocks exhibiting varying degrees of alteration have proven to be productive reservoir formations in a Norwegian North Sea oilfield. However, these reservoirs present significant challenges during drilling and lower completion design. Accurate assessment of the time-dependent borehole size and shape is essential for selecting optimal swell packer placement depths. Swell packers provide zonal isolation, separating productive intervals from faults, non-productive zones, loss zones, water-bearing layers, and distinct reservoir compartments. Borehole size evaluation also plays a critical role in real-time geomechanical wellbore stability assessments, drilling optimization, and completion design.
As part of the infill development program in Field A, two horizontal wells were recently drilled through conglomerate and fractured weathered basement lithologies. Previous well completions in these reservoir types encountered operational difficulties due to the absence of high-resolution ultrasonic caliper images and detailed trip-out-of-hole data needed to accurately identify borehole instabilities and understand their relationship to the reservoir’s structural and stratigraphic framework.
This paper presents a comprehensive workflow to improve swell packer depth selection and support optimization of the completion tally prior to installation of the lower completion string in a complex lithological environment. The workflow integrates high-resolution borehole characterization with geological and geomechanical evaluations to identify stable packer setting intervals, reduce completion-related risks, and enhance overall completion design efficiency in conglomerate and fractured basement reservoirs.
Bio:
Sayyid Ahmad is a Geoscientist and Image Log Analyst with the Geoscience & Production group at Halliburton in Norway. His current areas of interest include the integrated interpretation of advanced logging data for reservoir characterization and field development applications. Prior to joining Halliburton, Sayyid worked in Norway, Pakistan, and Houston, USA, as an exploration geoscientist. His areas of expertise include seismic interpretation, amplitude variation with offset (AVO) analysis, seismic inversion, synthetic seismic modeling (both convolutional and viscoelastic), and seismic processing. Sayyid holds a Ph.D. in Geophysics from the University of Stavanger, Norway, and an M.S. in Petroleum Geoscience Engineering from the University of Stavanger, Norway. He also earned a Bachelor’s degree in Mathematics and Physics from Quaid-i-Azam University, Pakistan.