Abstract: The present invention relates to a method for reducing the coning in an oil well of an underground reservoir delimited by an aquifer which comprises an injection phase of a micro(nano)-structured fluid with controlled release of barrier substances in said aquifer with the formation of an impermeable barrier located at the oil/water interface, characterized in that said fluid comprises an aqueous dispersion of microcapsules composed of a core comprising a modifying substance of the absolute permeability of the rock formation which contains said reservoir, a protective shell insoluble in water which coats said core. The present invention also relates to the above mentioned microcapsules and an aqueous dispersion comprising the above mentioned microcapsules to be used in said method.

Abstract: The present invention relates to a method for oil recovery from a reservoir which comprises the following phases: a) injecting a volume of a micro (nano)-structured fluid with released control of barrier substances into at least a portion of an underground reservoir containing oil, said micro (nano)-structured fluid comprising an aqueous dispersion of microcapsules composed of a core comprising a modifying substance of the absolute permeability of the rock formation which houses said reservoir, a protective shell insoluble in water which coats said core; b) clogging the porous intergranular spaces of said rock formation with said modifying substance with a reduction or inhibition of the absolute permeability of said rock formation, c) recovering said oil from the remaining portion of said reservoir by the further injection of a displacing fluid, preferably water.