A water-producing zone in a reservoir penetrated by a gravel-packed well is isolated by placing a bridge plug in the well tubing adjacent to the top of the water-producing zone, then placing a first coarse sand on the bridge plug, followed by a fine sand on top of the coarse sand, and finally by placing...http://www.google.es/patents/US5090478?utm_source=gb-gplus-sharePatente US5090478 - Method for reducing water production from a gravel packed well
Method for reducing water production from a gravel packed well
