摘要 |
A process for plugging an underground strata to prevent coning, i.e. the intrusion into an oil production stream of gas located above an oil producing foormation and/or water located below the formation from which the oil is being produced, by introducing a polymer or a surfactant together with a cosolvent into into a gaseous stream, e.g. carbon dioxide, in such ratio as to make the mixture just homogeneous when injected through the appropriate perforations into the zones above and below the oil bearing strata and yet subject to destabilization thereafter, either through some exiting feature of the reservoir such as temperature or the presence of water, or through some externally implemented event, such as a sudden lowering of the pressure in the vicinity of the well bore, to cause the polymer or surfactant to come out of solution and aid in plugging the zones through which vertical movement of gas and water, i.e. coning, had been taking place.
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