Controlled fracturing in geologic formations is carried out by a system for generating fractures. The system comprises: a plurality of electrodes for placing in boreholes in a formation with one electrode per borehole, for the plurality of electrodes to define a fracture pattern for the geologic formation; a first electrical system for delivering a sufficient amount of energy to the electrodes to generate a conductive channel between the pair of electrodes with the conductivity in the channel has a ratio of final to initial channel conductivity of 10:1 to 50,000:1, wherein the sufficient amount of energy is selected from electromagnetic conduction, radiant energy and combinations thereof; and a second electrical system for generating electrical impulses with a voltage output ranging from 100-2000 kV, with the pulses having a rise time ranging from 0.05-500 microseconds and a half-value time of 50-5000 microseconds.

A method of removing materials by their disintegration, especially metal tubes and non-metal materials, particularly in an area of a borehole, by thermal disintegration of materials by action of plasma created in a plasma generator, by hydrodynamic and/or gravitational removing of disintegrated materials from the area of the borehole, characterized in that a directed flow of water vapour-based plasma acts on material being disintegrated and disintegrates it by synergetic simultaneous effect of thermal action and exothermic chemical reactions.

A power condition system is disclosed for conditioning power for charging of at least one capacitive element of a pulse power electrode, where the electrical power is received from at least one of a downhole alternator or generator. The received electrical power is rectified and controlled for both voltage and current amplitude. The electrical power is then split into two parallel square wave signals. The electrical power is then transformed, using parallel high frequency high voltage transformers, to a high voltage signal. The high voltage signals are rejoined and rectified to produce a high voltage DC signal. The DC signal is smoothed at a high capacity inductor and output via a switching element to at least one capacitive element of the pulse power electrodes.

A power condition system is disclosed for conditioning power for charging of at least one capacitive element of a pulse power electrode, where the electrical power is received from at least one of a downhole alternator or generator. The received electrical power is rectified and controlled for both voltage and current amplitude. The electrical power is then split into two parallel square wave signals. The electrical power is then transformed, using parallel high frequency high voltage transformers, to a high voltage signal. The high voltage signals are rejoined and rectified to produce a high voltage DC signal. The DC signal is smoothed at a high capacity inductor and output via a switching element to at least one capacitive element of the pulse power electrodes.

Systems and methods for drilling a wellbore include delivering electrical energy to a downhole end of the wellbore. A tapered drill string, with larger drill pipes connected in an up-hole portion with a turbine and an electrical generator and a smaller drill pipes coupled in downhole portion may be used to deliver the electrical power. A turbine and generator may be sufficiently sized to harvest the necessary hydraulic energy and safely operated in a subterranean environment. An electrode carried by the downhole portion of the drill string is electrically coupled to the generator through the downhole portion of the drill string.

A method of mud logging is disclosed which the chemical constituents and concentrations of formation fluid are calculated based on pulse power plasma parameters and the constituent species and concentrations of drilling mud, including reaction products, upon which the pulse power plasma has acted. Based on correlation between pulse power plasma parameters, including drilling parameters, drilling can be optimized for identified formation and formation fluid species. An offset between the chemical makeup of the drilling mud exposed to pules power plasma and the chemical makeup of formation fluid is calculated. Based on the calculated offset, pulse power plasma drilling can be controlled as a function of drilling mud concentration including in other wellbores in the formation or field.

A method of mud logging is disclosed which the chemical constituents and concentrations of formation fluid are calculated based on pulse power plasma parameters and the constituent species and concentrations of drilling mud, including reaction products, upon which the pulse power plasma has acted. Based on correlation between pulse power plasma parameters, including drilling parameters, drilling can be optimized for identified formation and formation fluid species. An offset between the chemical makeup of the drilling mud exposed to pules power plasma and the chemical makeup of formation fluid is calculated. Based on the calculated offset, pulse power plasma drilling can be controlled as a function of drilling mud concentration including in other wellbores in the formation or field.

A laser cutting tool includes: an optical assembly that includes a laser generator that emits an laser beam; a reflector disposed longitudinally downstream of the laser generator; a reflector reflecting the laser beam emitted from the optical assembly; a focus lens disposed laterally beside the reflector; and a timer for controlling the tool to operate for at least one predetermined amount of time. The focus lens focuses the laser beam after it passes through the reflector.

In accordance with embodiments of the present disclosure, systems and methods for utilizing hybrid mechanical-laser drilling tools, such as drill bits and hole-openers, are provided. Such drilling tools may include mechanical cutters in addition to laser cutting mechanisms designed to focus laser beams toward a subterranean formation. The mechanical cutters and laser cutting mechanisms may work in combination to advance a wellbore through the subterranean formation. The drilling tools may be controlled to vary the amount of energy output through the mechanical drilling via the cutters and through the laser-assisted drilling via the lasers.

In accordance with embodiments of the present disclosure, systems and methods for utilizing hybrid mechanical-laser drilling tools, such as drill bits and hole-openers, are provided. Such drilling tools may include mechanical cutters in addition to laser cutting mechanisms designed to focus laser beams toward a subterranean formation. The mechanical cutters and laser cutting mechanisms may work in combination to advance a wellbore through the subterranean formation. The drilling tools may be controlled to vary the amount of energy output through the mechanical drilling via the cutters and through the laser-assisted drilling via the lasers.