US 10,539,012 B2 · Pulsed-electric drilling systems and methods with formation evaluation and/or bit position tracking

Abstract

Pulsed-electric drilling systems can be augmented with multi-component electromagnetic field sensors on the drillstring, at the earth's surface, or in existing boreholes in the vicinity of the planned drilling path. The sensors detect electrical fields and/or magnetic fields caused by the electrical pulses and derive therefrom information of interest including, e.g., spark size and orientation, bit position, at-bit resistivity and permittivity, and tomographically mapped formation strictures. The at-bit resistivity measurements can be for anisotropic or isotropic formations, and in the former case, can include vertical and horizontal resistivities and an orientation of the anisotropy axis. The sensors can illustratively include toroids, electrode arrays, tilted coil antennas, magnetic dipole antennas aligned with the tool axes, and magnetometers. The use of multiple such sensors increases measurement accuracy and the number of unknown model parameters which can be derived using an iterative inversion technique.

Claims20

Dependent claims

A pulsed-electric drilling system that comprises:

a drillstring terminated by a bit that extends a borehole through a formation ahead of the bit by passing pulses of electrical current into the formation;
one or more multi-component electromagnetic field sensors positioned on the drillstring, wherein the one or more multi-component electromagnetic field sensors comprises a set of sensing elements to measure fields, and wherein the set of sensing elements have at least one sensing element that is at a different axial orientation than another sensing element of the set of sensing elements, and wherein the fields are caused by the pulses of electrical current originating at the bit;
and
a processor that receives measurements representative of the fields measured by each of the set of sensing elements and derives, based at least in part on the measurements representative of the fields, a spark orientation at the bit and at least one electrical property of the formation.

1 more element

Dependencies are inferred from the claim text.

Pulsed-electric drilling systems and methods with formation evaluation and/or bit position tracking

Life of this patent

Pulsed-electric drilling systems and methods with formation evaluation and/or bit position tracking

Life of this patent

Abstract

Claims20