Electrically conductive proppant and methods for energizing and detecting same in a single wellbore

A method, comprising:

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

A method, comprising:

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

A method, comprising:

• performing one or more numerical simulations solving Maxwell's equations of electromagnetism for electric and/or magnetic fields to determine temporal characteristics of an optimum input wave form and a recording sensor array geometry to be used in a wellbore that extends from a surface of the earth into a subterranean formation having a fracture that is at least partially filled with an electrically conductive proppant, wherein the numerical simulations are based upon an earth model determined from geophysical logs and/or geological information;
• electrically energizing a casing of the wellbore;
• measuring three dimensional (x, y, and z) components of electric and/or magnetic field responses in the wellbore;
• and
• determining a location of the electrically conductive proppant through comparison of the electric and/or magnetic field responses to the numerical simulations, wherein the electrically conductive proppant is mixed with non-electrically conductive proppant to provide a proppant pack, and wherein the proppant pack comprises at least 40 wt % non-electrically conductive proppant.

A method, comprising:

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

A method of fracturing a subterranean formation, comprising:

• introducing a downhole tool comprising an energizing point and a sensor into a casing of a wellbore extending into the subterranean formation;
• electrically energizing the casing of the wellbore from the energizing point of the downhole tool;
• measuring three dimensional (x, y, and z) components of electric and/or magnetic field responses with the sensor in the wellbore to provide a first measurement;
• injecting a hydraulic fluid into the wellbore at a rate and pressure sufficient to open a fracture in the subterranean formation;
• injecting into the fracture a fluid containing a plurality of sintered, substantially round and spherical particles, each having a coating of an electrically conductive material having a thickness of at least 10 nm formed on an outer surface of the sintered, substantially round and spherical particles, wherein less than 90% of the outer surfaces of each of the sintered, substantially round and spherical particles are coated with the electrically conductive material and wherein the electrically conductive material is nickel;
• forming a proppant pack of the plurality of sintered, substantially round and spherical particles inside the fracture;
• reintroducing the downhole tool into the wellbore extending into the subterranean formation;
• electrically energizing the casing of the wellbore from the energizing point of the downhole tool;
• measuring three dimensional (x, y, and z) components of electric and/or magnetic field responses with the sensor in the wellbore to provide a first measurement to provide a second measurement;
• and
• determining a location of the electrically conductive proppant through comparison of the first and second measurements.

A method of fracturing a subterranean formation, comprising:

• introducing a downhole tool comprising an energizing point and a sensor into a casing of a wellbore extending into the subterranean formation;
• electrically energizing the casing of the wellbore from the energizing point of the downhole tool;
• measuring three dimensional (x, y, and z) components of electric and/or magnetic field responses with the sensor in the wellbore to provide a first measurement;
• injecting a hydraulic fluid into the wellbore at a rate and pressure sufficient to open a fracture in the subterranean formation;
• injecting into the fracture a fluid containing a plurality of sintered, substantially round and spherical particles, each having a coating of an electrically conductive material having a thickness of at least 10 nm formed on an outer surface of the sintered, substantially round and spherical particles;
• forming a proppant pack of the plurality of sintered, substantially round and spherical particles inside the fracture;
• reintroducing the downhole tool into the wellbore extending into the subterranean formation;
• electrically energizing the casing of the wellbore from the energizing point of the downhole tool;
• measuring three dimensional (x, y, and z) components of electric and/or magnetic field responses with the sensor in the wellbore to provide a first measurement to provide a second measurement;
• determining a location of the electrically conductive proppant through comparison of the first and second measurements;
• prior to injecting the hydraulic fluid into wellbore, performing one or more numerical simulations solving Maxwell's equations of electromagnetism for electric and/or magnetic fields to determine temporal characteristics of an optimum input wave form and a recording sensor location to be used in the wellbore, wherein the numerical simulations are based upon an earth model determined from geophysical logs and/or geological information;
• and
• analyzing the three dimensional (x, y, and z) components with imaging methods including an inversion algorithm based on Maxwell's equations for electromagnetism and/or electromagnetic holography to determine the location of the proppant pack, wherein, in the electromagnetic holography, the electric and/or magnetic field responses and a source wave form are projected into an earth volume to form an image of proppant pack using constructive and destructive interferences.