New Production in Old Fields: Case Study in the Hunton Dolomite

Unger Field, discovered in 1955, has produced 8.6 million barrels of oil from a thinly (several ft) bedded, locally cherty dolomite containing vuggy and intercrystalline porosity. Today, the Siluro–Devonian Hunton Group reservoir is produced from 17 of the original 76 wells at an average rate of 2.6 BOPD. Water cut is high, indicative of a strong water drive. However, as wells are pumped hard oil production can increase, suggesting that bypassed oil remains.

Topics to be covered in this e-symposium include:

• Background on 57-year old Unger Field evaluating potential for bypassed production.
• Pre-spud analysis
• Regional and local structure and evaluating well trajectory.
• Stratigraphic framework of Hunton Dolomite reservoir mapping including flow unit characterization using old well logs.
• Well planning for soft land the well into top of the pay zone, set casing in pay and and drill out.
• Results
• Evaluation while drilling using azimuthal gamma ray, samples, and penetration rate.
• Post drill well shuttle logging with triple combo and imaging log to characterize fracture cluster and pay interval.
• Slotted liner completion to isolate the pay interval.
• Increased oil production from new well and nearby leases.
• Update on performance and options to further increase production.