Methods of characterizing earth formations using physiochemical model

A method of characterizing an earth formation, comprising:

• a) constructing a reservoir model of the earth formation from data obtained from a plurality of sources, the reservoir model including a plurality of layers;
• b) selecting a predetermined set of fundamental parameters to describe the earth formation, including porosity (ϕ), pore-to-throat size ratio (α), cation-exchange capacity (Qv), a mineral array (M), residual water (Swr), maximum residual oil saturation (Snrm), cementation exponent (m), saturation exponent (n), Corey exponent (λBC), and pore aspect ratio (η);
• c) assigning initial values for the predetermined set of fundamental parameters for each of the plurality of layers;
• d) using the initial values for each of the plurality of layers, solving partial differential equations of transport to obtain solutions for a plurality of field variables of the earth formation including pressure, saturation, temperature, and fluid composition as a function of space and time for each of the plurality of layers;
• e) computing physical-response-relevant properties as a function of space and time for each of the plurality of layers using the solutions;
• f) computing tool responses using the physical-response-relevant properties including a electrically-based property, a density-based property, a acoustically-based property, and a nuclear-based property;
• g) installing an electrode array between an insulation portion of a metal casing provided in a borehole and a physical formation and obtaining formation measurement information from the electrode array, wherein the borehole is a partly conductive fluid-filled borehole;
• h) comparing the formation measurement information to the computed tool response to obtain an error signal;
• i) modifying the initial values in an iterative process utilizing the error signal and repeating d) with modified values, e), f), g), h), and i) in a multidimensional search until the error signal is deemed acceptable, thereby characterizing the earth formation;
• j) determining values for the predetermined set of fundamental parameters for the plurality of layers of the formation;
• and
• k) displaying the determined values for a of the predetermined set of fundamental parameters.