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The paper aims at investigating some issues related to the theoretical and numerical modelization of subsidence phenomena induced by hydrocarbon withdrawal. First a brief review of the implications of facing the problem as coupled / uncoupled is provided accordingly to the theory of mechanics of porous media as formulated by Biot. On the basis of these considerations, the classical nucleus of strain solution given by Geertsma is coupled to the hydrodinamic problem of a single phase fluid draining towards a well. The approach implemented has the advantage of providing a series of subsidence profiles evolving with time, together with the well production. The problem is handled both introducing or not the possibility of hydromechanical nonlinearities in the behaviour of the reservoir rock. When accounted, the mechanical nonlinearity is accomplished by assuming that the rock deforms accordingly to classical logarithmic relationships for oedometric stress paths, as foreseen by critical state models such as Cam Clay. On its turn the hydraulic nonlinearity is accounted for by implementing a literature relationship valid for Mexico Gulf sands, postulating that an exponential relationship exists between porosity and permeability.