Abstract:
The disclosure provides a borehole tool for seismic data collection. The tool comprises a cable to be positioned within a borehole and at least one sensor for measuring seismic signals mounted on the cable. The sensors provide measurements of particle motion (velocity or acceleration) perpendicular to an axis of the borehole. The disclosure also provides methods of seismic surveying, which involves positioning the tool in the borehole, firing a seismic source generating a seismic wave and measuring particle motion associated with the passing seismic wave perpendicular to an axis of the borehole using the at least one sensor for measuring particle motion.
Abstract:
A remotely actuated clamping device for a borehole seismic sensing system. The remotely actuated clamping device includes a clamping mechanism configured to engage a surface of a borehole by actuation of the clamping mechanism. The remotely actuated clamping device also includes a fluid based actuator configured to actuate the clamping mechanism. The fluid based actuator includes a chamber configured to be kept at a pressure that is isolated from an ambient pressure of the borehole. The fluid based actuator also includes a piston within the chamber. The chamber receives a pressurized fluid to move the piston within the chamber to actuate the clamping mechanism. The pressure used to actuate the clamping mechanism is independent of the ambient pressure of the borehole. Also disclosed are methods of operating the device.
Abstract:
A multitude of seismic sources are formed into a linear array which can be permanently cemented within a wellbore. The seismic sources can be orbital vibrators that are electrically connected and protected from the cementing by use of pieces of drill pipe and tubing that are interconnected and provide a container for electrical connection of the seismic sources and provide surface access through a surface vault.
Abstract:
A sensor flap for a downhole tool. The downhole tool is positionable in a wellbore penetrating a subterranean formation. The sensor flap includes a sensor housing and at least one sensor. The sensor housing is operatively connectable to the downhole tool. The sensor housing is movably positionable between a retracted position in the downhole tool and an extended position in contact with a wall of the wellbore. The sensor is positionable in the sensor housing, and may include a seismic detector to measure seismic activity when the sensor housing is in contact with the wall of the wellbore.
Abstract:
In one aspect, the disclosure provides an apparatus for use downhole that includes at least one acoustic sensor. In one aspect, the acoustic sensor includes a chamber and an active element comprised of a quantum tunneling composite in the chamber. In another aspect, the acoustic sensor may further include a pair of conductive layers on a pair of sides of the active element. The chamber is filled with an electrically non-conductive fluid. The active element may be placed in the chamber in a manner that causes the active element to be responsive to acoustic waves along a selected direction or in a manner that enables the active element to be non-directional.
Abstract:
Systems and method described herein provide for obtaining information which can be used to create a seismic image of a portion of the earth surrounding a well. A device for obtaining information for creating a seismic image proximate a well includes at least one set of acoustic transducers mounted to an exterior surface of a well tubing and configured to transmit at least one acoustic signal, at least one set of hydrophones mounted to the exterior surface of the well tubing and configured to receive at least one reflected acoustic signal; and a cable configured to convey information to and from the at least one set of acoustic transducers and the at least one set of hydrophones.
Abstract:
The present disclosure relates to methods and apparatuses measuring a property of a material. The apparatus may include a transducer comprising a first electrical conductor, a second electrical conductor, and a piezoelectric component configured to receive the two conductors. The piezoelectric component may include a cavity dimensioned to improve the strength of or reduce stress on an interconnection between piezoelectric component and at least one of the conductors. The method may include using one or more transducers measuring a property of a material. In some embodiments, the material may be an earth formation.
Abstract:
In one aspect, the disclosure provides an apparatus for use downhole that includes at least one acoustic sensor. In one aspect, the acoustic sensor includes a chamber and an active element comprised of a quantum tunneling composite in the chamber. In another aspect, the acoustic sensor may further include a pair of conductive layers on a pair of sides of the active element. The chamber is filled with an electrically non-conductive fluid. The active element may be placed in the chamber in a manner that causes the active element to be responsive to acoustic waves along a selected direction or in a manner that enables the active element to be non-directional.
Abstract:
A downhole receiver for gathering seismic and sonic data from inside a borehole includes a substantially tubular housing adapted for axial connection to a tool string, and one or more sensors. A damping element is provided to flexibly couple each sensor to the tubular housing. An actuator extends the one or more sensors substantially radially with respect to the tubular housing to clamp the sensors against the wall of the borehole. In selected embodiments, the sensors may be one or multiple component geophones, accelerometers, hydrophones, vibrometers, or the like.