Abstract: This disclosure presents an apparatus and system for lowering the cost of implementing a downhole sensor system using attachable collars. In some aspects, the attachable collar includes a transmitter component, while supporting electronics are included with a main collar, thereby reducing the cost of the attachable collar. The supporting electronics can send a transmission signal, a control signal, a synchronization clock signal, a selected transmission frequency, a sensor orientation and selection, and other instructions to the transmitter in the attachable collar. The receiver in the main collar can receive the output, as reflected by the subterranean formation, and transform the output to subterranean formation evaluation measurements. The measurements can be communicated to other systems. In some aspects, the attachable collar can include the receiver and the main collar can include the transmitter.

Abstract: A method of fabricating a ferrite for use in a resistivity logging tool includes providing an uncured ferrite material, and pressing the uncured ferrite material into a channel to form the ferrite. The channel is defined on a surface of a bobbin associated with the resistivity logging tool, and the channel can be arcuate and extend at an angle offset from a central axis of the bobbin. The uncured ferrite material is then cured in place within the channels on the bobbin.

Abstract: A ranging system and method uses three-dimensional (“3D”) magnetic field measurements to correct ranging distance and direction. Ghost well interference may also be decoupled from the ranging solutions using 3D magnetic gradient field measurements.

Abstract: A compact sub assembly and well measurement system. The compact sub assembly may comprise a deep transmitter disposed about one end of the compact sub assembly, a shallow dual transmitter disposed on the compact sub assembly between the deep transmitter and a second end of the compact sub assembly, a shallow dual-collocated receiver disposed on the compact sub assembly between the deep transmitter and a second end of the compact sub assembly, and a deep receiver disposed about the second end of the compact sub assembly. A well measurement system for decoupling a component signal may comprise a logging tool. The logging tool may comprise a first sub assembly and a conveyance attached to the logging tool. In examples the first sub assembly is a compact sub assembly comprising a deep transmitter, a shallow dual transmitter, a shallow dual-collocated receiver, and a deep receiver.

Abstract: An antenna assembly includes a tool mandrel having a tool axis, and a coil including a plurality of windings wrapped about the tool mandrel at a winding angle offset from the tool axis. A soft magnetic band radially interposes the coil and the tool mandrel and extends about a circumference of the tool mandrel at a band angle parallel to the winding angle. The soft magnetic band includes a plurality of stacked inserts extending perpendicular to the coil about the circumference of the tool mandrel and each stacked insert includes a plurality of rods positioned end-to-end.

Abstract: A ranging system and method uses three-dimensional (“3D”) magnetic field measurements to correct ranging distance and direction. Ghost well interference may also be decoupled from the ranging solutions using 3D magnetic gradient field measurements.

Abstract: This disclosure presents an apparatus and system for lowering the cost of implementing a downhole sensor system using attachable collars. In some aspects, the attachable collar includes a transmitter component, while supporting electronics are included with a main collar, thereby reducing the cost of the attachable collar. The supporting electronics can send a transmission signal, a control signal, a synchronization clock signal, a selected transmission frequency, a sensor orientation and selection, and other instructions to the transmitter in the attachable collar. The receiver in the main collar can receive the output, as reflected by the subterranean formation, and transform the output to subterranean formation evaluation measurements. The measurements can be communicated to other systems. In some aspects, the attachable collar can include the receiver and the main collar can include the transmitter.

Abstract: A logging tool includes a mandrel having an axis, a bobbin positioned about the circumference of the mandrel, and defining a first cross slot at a first slot angle and a second cross slot at a second slot angle opposite the first slot angle. The first and second cross slots intersect each other. The tool includes a first antenna in the first slot and including a first plurality of windings wrapped about the mandrel, a second antenna co-located with the first antenna and in the second slot, and an antenna shield secured to the tool mandrel and in each of the first and second slots. The first antenna is arranged in a first orientation and at a first winding angle. The second antenna is arranged in a second orientation and at a second winding angle.

Abstract: A logging tool includes a mandrel having a tool axis, a first loop antenna including first windings wrapped about the mandrel, a second loop antenna co-located with the first loop antenna and including second windings wrapped about the mandrel, and a shield secured to the mandrel. The first loop antenna is in a first orientation and the first windings are wrapped at a first angle. The second loop antenna is in a second orientation opposite the first orientation and the second windings are wrapped at a second angle. The shield includes first slots overlapping and along the first loop antenna and second slots overlapping and along the second loop antenna. The first slots define a first trace angle with respect to the tool axis and different from the first angle. The second slots defines a second trace angle with respect to the tool axis and different from the first angle.

Abstract: An antenna assembly includes a tool mandrel having a tool axis and a coil including a plurality of windings wrapped about the tool mandrel at a winding angle offset from the tool axis. An antenna shield is secured to the tool mandrel and positioned radially outward from the coil. The antenna shield defines a plurality of slots extending perpendicular to the coil at any angular location about a circumference of the tool mandrel and the plurality of slots is provided in two or more dissimilar lengths.

Abstract: A method of fabricating a ferrite for use in a resistivity logging tool includes providing an uncured ferrite material, and pressing the uncured ferrite material into a channel to form the ferrite. The channel is defined on a surface of a bobbin associated with the resistivity logging tool, and the channel can be arcuate and extend at an angle offset from a central axis of the bobbin. The uncured ferrite material is then cured in place within the channels on the bobbin.

Abstract: A logging tool includes a mandrel having a tool axis, a first loop antenna including first windings wrapped about the mandrel, a second loop antenna co-located with the first loop antenna and including second windings wrapped about the mandrel, and a shield secured to the mandrel. The first loop antenna is in a first orientation and the first windings are wrapped at a first angle. The second loop antenna is in a second orientation opposite the first orientation and the second windings are wrapped at a second angle. The shield includes first slots overlapping and along the first loop antenna and second slots overlapping and along the second loop antenna. The first slots define a first trace angle with respect to the tool axis and different from the first angle. The second slots defines a second trace angle with respect to the tool axis and different from the first angle.

Abstract: A logging tool includes a mandrel having an axis, a bobbin positioned about the circumference of the mandrel, and defining a first cross slot at a first slot angle and a second cross slot at a second slot angle opposite the first slot angle. The first and second cross slots intersect each other. The tool includes a first antenna in the first slot and including a first plurality of windings wrapped about the mandrel, a second antenna co-located with the first antenna and in the second slot, and an antenna shield secured to the tool mandrel and in each of the first and second slots. The first antenna is arranged in a first orientation and at a first winding angle. The second antenna is arranged in a second orientation and at a second winding angle.

Abstract: A compact sub assembly and well measurement system. The compact sub assembly may comprise a deep transmitter disposed about one end of the compact sub assembly, a shallow dual transmitter disposed on the compact sub assembly between the deep transmitter and a second end of the compact sub assembly, a shallow dual-collocated receiver disposed on the compact sub assembly between the deep transmitter and a second end of the compact sub assembly, and a deep receiver disposed about the second end of the compact sub assembly. A well measurement system for decoupling a component signal may comprise a logging tool. The logging tool may comprise a first sub assembly and a conveyance attached to the logging tool. In examples the first sub assembly is a compact sub assembly comprising a deep transmitter, a shallow dual transmitter, a shallow dual-collocated receiver, and a deep receiver.

Abstract: A method of processing data from an electromagnetic resistivity logging tool which includes a transmitter coil and a receiver coil is disclosed. The electromagnetic resistivity logging tool is placed at a desired location. The transmitter coil and the receiver coil are positioned at a first azimuthal angle. A signal is transmitted from the receiver coil. The receiver coil then receives a signal. The signal at the receiver coil, a tilt angle of the transmitter coil, a tilt angle of the receiver coil and the first azimuthal angle are then used to calculate a first complex voltage representing at least one component of the received signal.

Abstract: An antenna assembly includes a tool mandrel having a tool axis and a coil including a plurality of windings wrapped about the tool mandrel at a winding angle offset from the tool axis. An antenna shield is secured to the tool mandrel and positioned radially outward from the coil. The antenna shield defines a plurality of slots extending perpendicular to the coil at any angular location about a circumference of the tool mandrel and the plurality of slots is provided in two or more dissimilar lengths.

Abstract: Methods and compositions for treating subterranean formations, and more specifically, to smart fracturing fluids. In one or more embodiments, the methods comprise providing a fracturing fluid that comprises a base fluid and an additive having a high dielectric constant; and introducing the fracturing fluid into least a portion of a subterranean formation. In one or more embodiments, the compositions comprise a base fluid and an additive having a high dielectric constant.

Abstract: An antenna assembly includes a tool mandrel having a tool axis, and a coil including a plurality of windings wrapped about the tool mandrel at a winding angle offset from the tool axis. A soft magnetic band radially interposes the coil and the tool mandrel and extends about a circumference of the tool mandrel at a band angle parallel to the winding angle. The soft magnetic band includes a plurality of stacked inserts extending perpendicular to the coil about the circumference of the tool mandrel and each stacked insert includes a plurality of rods positioned end-to-end.

Abstract: A method of processing data from an electromagnetic resistivity logging tool which includes a transmitter coil and a receiver coil is disclosed. The electromagnetic resistivity logging tool is placed at a desired location. The transmitter coil and the receiver coil are positioned at a first azimuthal angle. A signal is transmitted from the receiver coil. The receiver coil then receives a signal. The signal at the receiver coil, a tilt angle of the transmitter coil, a tilt angle of the receiver coil and the first azimuthal angle are then used to calculate a first complex voltage representing at least one component of the received signal.

Abstract: A method of processing data from an electromagnetic resistivity logging tool which includes a transmitter coil and a receiver coil is disclosed. The electromagnetic resistivity logging tool is placed at a desired location. The transmitter coil and the receiver coil are positioned at a first azimuthal angle. A signal is transmitted from the receiver coil. The receiver coil then receives a signal. The signal at the receiver coil, a tilt angle of the transmitter coil, a tilt angle of the receiver coil and the first azimuthal angle are then used to calculate a first complex voltage representing at least one component of the received signal.