Abstract: A drilling system provides indications of the lithology of the formation being drilled by dynamically measuring at least one parameter of interest that is affected by the lithology of the formation being drilled. Suitably positioned sensors make dynamic measurements of parameters such as downhole weight on bit, bit torque, bit revolutions, rate of penetration and bit axial acceleration. One or more processors use the sensor measurements in conjunction with predetermined lithological models to determine whether the measurements indicate a change in formation lithology. Suitable models can be on derived expressions such as rock drillability, drilling response, dynamic drilling response, normalized or dimensionless torque; and formation shear strength. The lithological indications provided by the processor can be used to adjust drilling parameters, steer the BHA, monitor BHA health, and provide depth locations for bed boundaries and formation interfaces.

Abstract: A bottomhole assembly (BHA) for single trip sidetracking operations has a mill for forming an open hole section in a cased wellbore and a steering unit for controlling drill bit orientation. During use, the drilling system is assembled at the surface and tripped into the wellbore. The mill is positioned adjacent a kick-off point and operated to form an open hole section. Thereafter, the drill bit is positioned adjacent the open hole section. An exemplary steering unit includes one or more force application members that, when energized, displace the drill bit such that the bit is pointed in a specified direction into the open hole section. The steering unit also includes one or more force application members that facilitate directional drilling through the open hole section. Other suitable steering units can employ devices that alter the BHA centerline geometry.

Abstract: A system and method for communicating information between downhole equipment in a wellbore and surface equipment, comprising a first device disposed in a wellbore for receiving at least one first signal and transmitting at least one second signal. A surface device is used for receiving the at least one second signal and transmitting the at least one first signal. At least one repeater is disposed at a predetermined location in a wall of the wellbore for receiving and retransmitting the first signal and the second signal. A method for communicating information between downhole equipment in a wellbore and surface equipment, comprises deploying a tubular member in the wellbore, the tubular member having a transmitter disposed therein; disposing at least one signal repeater at a predetermined location in a wall of the wellbore; and transmitting a signal from the transmitter to a surface receiver through the at least one repeater.

Abstract: A drilling system provides indications of the lithology of the formation being drilled by dynamically measuring at least one parameter of interest that is affected by the lithology of the formation being drilled. Suitably positioned sensors make dynamic measurements of parameters such as downhole weight on bit, bit torque, bit revolutions, rate of penetration and bit axial acceleration. One or more processors use the sensor measurements in conjunction with predetermined lithological models to determine whether the measurements indicate a change in formation lithology. Suitable models can be on derived expressions such as rock drillability, drilling response, dynamic drilling response, normalized or dimensionless torque; and formation shear strength. The lithological indications provided by the processor can be used to adjust drilling parameters, steer the BHA, monitor BHA health, and provide depth locations for bed boundaries and formation interfaces.

Abstract: A bottomhole assembly (BHA) for single trip sidetracking operations has a mill for forming an open hole section in a cased wellbore and a steering unit for controlling drill bit orientation. During use, the drilling system is assembled at the surface and tripped into the wellbore. The mill is positioned adjacent a kick-off point and operated to form an open hole section. Thereafter, the drill bit is positioned adjacent the open hole section. An exemplary steering unit includes one or more force application members that, when energized, displace the drill bit such that the bit is pointed in a specified direction into the open hole section. The steering unit also includes one or more force application members that facilitate directional drilling through the open hole section. Other suitable steering units can employ devices that alter the BHA centerline geometry.

Abstract: The present invention provides a method and apparatus for acoustic position logging ahead of a drill bit. The method and apparatus comprise a bottomhole assembly (BHA) conveyed on a drilling tubular in a borehole within an earth formation. The BHA has a source array for emitting preselected acoustic signals into the earth formation, and at least one receiver on the BHA for receiving a second acoustic signal produced by an interaction of the preselected acoustic signal with said formation. The source array for acoustic energy may be configured as an axially distributed array of axially or azimuthally directed sources, or an azimuthally distributed array of axially or azimuthally directed sources. The sources may be activated according to preselected time delays. The emitted acoustic signal is differing in spectrum and/or wave mode from the acoustic energy of a rotating drill string.

Abstract: A system and method for communicating information between downhole equipment in a wellbore and surface equipment, comprising a first device disposed in a wellbore for receiving at least one first signal and transmitting at least one second signal. A surface device is used for receiving the at least one second signal and transmitting the at least one first signal. At least one repeater is disposed at a predetermined location in a wall of the wellbore for receiving and retransmitting the first signal and the second signal. A method for communicating information between downhole equipment in a wellbore and surface equipment, comprises deploying a tubular member in the wellbore, the tubular member having a transmitter disposed therein; disposing at least one signal repeater at a predetermined location in a wall of the wellbore; and transmitting a signal from the transmitter to a surface receiver through the at least one repeater.

Abstract: The present invention provides a drilling assembly with a stabilization system that stabilizes at least a section of the drilling assembly as a function of one or more downhole measured parameters or parameters of interest. One or more sensors carried by the drilling assembly measure the desired parameters of interest and a control system controls the stabilizer system in response to one or more determined parameters of interest to provide desired stabilization of a section of the drilling assembly. Measurement-while-drilling sensors whose measurements are affected by the parameters of interest are preferably disposed in the stabilized section. In one embodiment, the stabilization system includes at least two axially spaced apart stabilizers. Each such stabilizer includes a plurality of independently adjustable members that radially extend from the drilling assembly to exert force on the wellbore inside.

Abstract: The present invention discloses a drilling tool apparatus and method for sinking drill holes in underground rock formations while using a selectable direction profile for the drill hole.