Press Esc to close



For full content view: Log in Now!

  • Wettability alteration used for water block prevention in high-temperature gas wells

    M. Panga, Y. Ooi, K. Chan, P. Enkababian, M. Samuel, P. Koh and P. Cheneviere

    Water accumulation near the wellbore or fracture face can decrease the relative permeability of oil and gas. This restriction to oil and gas flow, due to increased water saturation, is called water block. Sources for excess formation water could be water-based fluids used in drilling, completion, matrix or fracture treatments; cross-flow of water to dry gas zones; or water imbibition into tight zones. The excess water is trapped in the formation, due to high capillary pressure in porous rock and viscous fingering of gas through water. The presence of clays, migrating fines, reservoir heterogeneity and other forms of formation damage, such as wettability alterations, can increase the severity of trapping. Laboratory studies by Kamath and Laroche, and Mahadevan and Sharma, have shown that removal of water from the formation occurs in two stages—an initial displacement stage where water is expelled from the core, followed by a long-term evaporation stage.

This area of the site is restricted. In order to gain access, please either Log In, or subscribe to World Oil.

Two options are available to you for creating an account.

1. Get a Free Trial Subscription to World Oil Magazine and gain immediate access to select content on World Oil Online.

Start a Free Trial Subscription and gain immediate access to the complete current issue of World Oil Magazine. Plus, you’ll receive 3 upcoming issues of World Oil Magazine in print or digital format.* You also receive access to the Energy Events Calendar, Industry Statistics and WO Wire’s news and industry coverage.

Free Trial

2. Purchase a subscription to World Oil magazine and gain immediate and complete access to World Oil Online. As a Total Access subscriber you will have access to all areas of the site available to registered users and free subscribers as well as having access to such premium content areas as:

  • The Archives section containing over ten years of complete magazine archives,
  • The WO DataHub's engineering tables and directories,
  • The World Oil annual forecasts, including past predictions,
  • Select World Oil technical handbooks,
  • And much, much more!


Physical copies of this content may be available for purchase. Visit the Reprints & Back Issues section.

If you are already a paid subscriber and do not have access, please email



Engineering Data Tables

World Oil's specialized upstream Engineering Data Tables featuring the Drill Bit Classifier, Tubing Tables and more. Get Total Access today.


2013 Fracturing Technology

2013 Fracturing Technology