Multi-frequency dielectric borehole imager
AssigneeHalliburton Energy Services, Inc.
InventorsBurkay Donderici, Luis San Martin
Life of this patent
Estimating the term…
Abstract
Systems, methods and devices for dielectric borehole imagery are disclosed. Systems may include one or more transmitters that induce, at azimuthally-spaced positions on a borehole wall, a plurality of fields having components in non-coplanar directions within a formation; one or more directionally sensitive receivers that sense the components caused by each of the one or more transmitters; and a controller that processes signals received from the one or more directionally sensitive inductive sensors to provide a set of measurements representative of dielectric parameters at two or more azimuthal positions within the borehole.
Claims19
A dielectric borehole imaging tool for use in a borehole extending through a subterranean formation, the borehole having a borehole wall, the tool comprising:
- one or more transmitters that induce, at azimuthally-spaced positions on the borehole wall, a plurality of fields having components in non-coplanar directions within the formation;
- directionally sensitive inductive receivers configured to sense the components caused by each of the one or more transmitters;
- and a controller configured to process signals received from the directionally sensitive inductive receivers to provide a set of measurements representative of dielectric parameters and resistivity at two or more azimuthal positions within the borehole, wherein the dielectric parameters comprise a dielectric constant in horizontal and vertical directions.
A multi-axial induction borehole imaging system for use in a borehole extending through a subterranean formation, the borehole having a borehole wall, the system comprising:
- a tool body movable within the borehole through the formation and comprising one or more sensor pads configured to measure dielectric parameters as a function of position and azimuth on the borehole wall, wherein each sensor pad comprises a set of one or more transmitters and one or more receivers respectively configured to induce and sense one or more fields within the formation, wherein the one or more receivers are configured to provide signals representative of independent directional components of the one or more fields;
- a downhole controller configured to process the signals to provide a set of measurements representative of dielectric parameters of the formation at each position and azimuth;
- and a computer system configured to receive and derive from the set of measurements one or more borehole characteristics comprising dielectric parameters and resistivity associated with each position and azimuth and further presents to a user data representative of at least one of the one or more borehole characteristics, wherein the borehole characteristics comprise dielectric constant in two different directions, and wherein said two different directions are horizontal and vertical directions.
A dielectric borehole imaging method comprising:
- lowering a dielectric borehole imaging tool into a borehole through a formation;
- at each of multiple positions on the borehole wall, inductively inducing multi-frequency fields having linearly-independent directional components within a formation;
- inductively detecting the directional field components to obtain, as a function of azimuthal angle and position in the borehole, measurements representative of dielectric parameters of the formation from the detected field components;
- deriving from the measurements one or more borehole characteristics comprising dielectric parameters and resistivity as a function of the azimuthal angle and position in the borehole;
- and presenting to a user data representative of the one or more borehole characteristics;
- wherein the one or more borehole characteristics comprise dielectric constant in two different directions, and wherein said two different directions are horizontal and vertical directions.
Dependencies are inferred from the claim text.