Sustaining long-term well production in deep gas wells can exhibit
unique challenges in shaly sands. The wells can be vertical or slanted gas
producers and completed with stand-alone screens. The challenges were to
quantify zonal contributions, detect smaller water entries on these
high-temperature deep gas wells where reservoir heterogeneity with different
depletion layers can result in strong crossflow, and evaluate the existing sand
formation behind the screen to avoid restricting the wells' productivity.
This paper describes an integrated approach taken to overcome these
challenges with three field examples. A multiphase production logging tool was
run to measure the water flow together with the gas contributions across the
stand-alone screens on these wells. A pulsed neutron logging tool was run to
identify the small amount of water by using a water flow log model. Ton assess
and evaluate the conditions of sand behind the screens, two independent logging
techniques were implemented: silica activation and carbon-oxygen inelastic
silicon yield techniques.
A combination of pre-job planning, an optimized logging program, and
proactive real-time monitoring allowed a safe logging operation by drastically
minimizing the time exposed by the tool downhole in a high-temperature
environment. Early monitoring of water production is important to achieve
optimal well productivity and reduce the possibility of the hydrate formation
obstructing the flow lines. The source of sand production and the quality of
the packing behind the screen were also evaluated. This best practice was
established in the field and will greatly improve well deliverability and
maximize gas field production.
THIS ITEM IS PREMIUM CONTENT. TO ACCESS THE FULL CONTENT, SIGN IN OR REGISTER BELOW.