A method to reduce water influx into a producing well is described comprising
the
steps of pumping a chemical composition into a production interval and into surrounding
formation; said composition being capable of forming, firstly, a physically stabilized
structure and, secondly, a chemically stabilized structure, wherein said physically
stabilized structure being dissolvable by hydrocarbon containing fluids; letting
said composition form said physically stabilized structure within the formation
surrounding said production interval; changing pressure condition in said production
interval such that the fluid flow within the surrounding formation is reversed;
letting thereby in some portions of the formation hydrocarbon containing fluids
dissolve said physically stabilized structure and chemically stabilize said structure
in the remaining portions by a cross-linking reaction. The time constants of the
two stabilizing reactions are selected such that the physical stabilization is
essentially completed before the pumping direction is reversed and the chemical
stabilization is essentially completed after the pump-out/cleaning operation.
