Formation water has an ever increasing negative impact on the producing reservoirs during long-lasting operation of gas wells. This is confirmed by the experience of developing depleted reservoirs of Medvezhye, Urengoyskoye and Yamburgskoye fields where we currently observe progressive processes that have a negative impact on porosity and permeability properties of the producing formations and lead to reduction of gas (oil) output.

Objectively, many gas fields in the northern part of Western Siberia are mature ones with intensive inflow of formation water and its accumulation in well bottoms what leads to self-killing of such wells and producing formations. Destruction of bottomhole zone and appearance of sandy-clayey plugs in a wellbore – these are the main negative consequences of water encroachment of producing horizons.

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