Electrically conductive proppant and methods for detecting, locating and characterizing the electrically conductive proppant

A method, comprising:

• performing one or more numerical simulations solving Maxwell's equations of electromagnetism for magnetic fields to determine temporal characteristics of an optimum input wave form and a recording sensor array geometry to be used in a field, wherein the numerical simulations are based upon an earth model determined from geophysical logs and/or geological information;
• electrically energizing a casing of a wellbore in the field that extends from a surface of the earth into a subterranean formation having a fracture that is at least partially filled with proppant and an electrically-conductive material;
• measuring three dimensional (x, y, and z) components of magnetic field responses at the surface or in an adjacent wellbore;
• and
• determining a location of the proppant through comparison of the magnetic field responses to the numerical simulations.

A method for characterizing a hydraulically-induced fracture, comprising:

• performing one or more numerical simulations solving Maxwell's equations of electromagnetism, wherein the numerical simulations are based upon an earth model containing parameters comprising proppant location within a fracture and a net electrical conductivity of the fracture;
• electrically energizing a casing of a wellbore in a field that extends from a surface of the earth into a subterranean formation having a fracture that is at least partially filled with proppant and an electrically-conductive material to generate electromagnetic field responses;
• detecting the electromagnetic field responses with a plurality of sensors to provide measured electromagnetic field responses;
• and
• analyzing the measured electromagnetic field responses with an inversion algorithm based on Maxwell's equations for electromagnetism to determine a location of the proppant, wherein analyzing the measured electromagnetic field responses includes adjusting the parameters of the model to fit the measured electromagnetic field responses.

A method for characterizing a hydraulically-induced fracture, comprising:

• electrically energizing a casing of a wellbore in a field that extends from a surface of the earth into a subterranean formation having a fracture that is at least partially filled with proppant and an electrically-conductive material, wherein the electrically-conductive material is coated with a water soluble coating for delayed release of the electrically-conductive material into the fracture;
• obtaining electromagnetic field responses with a plurality of sensors;
• and
• analyzing the electromagnetic field responses with an inversion algorithm based on Maxwell's equations for electromagnetism to determine the location of the proppant.