The method of maintaining drill bit advancement in an underground formation that contains shale, including providing an electrical signal from an insulated gap location in a drill string substantially directly behind the bit in the formation, detecting substantial change in a signal as the bit advances, and changing the direction of drilling of the bit as a function of a signal change, to thereby maintain the direction of bit advancement in the formation. A method is disclosed for detecting the existence and direction of adjacent bed boundaries. A short hop transmitter assembly generates a signal that is detected by an associated receiver assembly. The received signal(s) are tied to the azimuthal orientation of the transmitter or receiver and processed to yield the direction and/or the distance of the bed boundary. This information is transmitted to the surface via surface telemetry for real-time control of the drilling assembly to stay within, or to enter, a pay zone.

The method of maintaining drill bit advancement in an underground formation that contains shale, including providing an electrical signal from an insulated gap location in a drill string substantially directly behind the bit in the formation, detecting substantial change in a signal as the bit advances, and changing the direction of drilling of the bit as a function of a signal change, to thereby maintain the direction of bit advancement in the formation. A method is disclosed for detecting the existence and direction of adjacent bed boundaries. A short hop transmitter assembly generates a signal that is detected by an associated receiver assembly. The received signal(s) are tied to the azimuthal orientation of the transmitter or receiver and processed to yield the direction and/or the distance of the bed boundary. This information is transmitted to the surface via surface telemetry for real-time control of the drilling assembly to stay within, or to enter, a pay zone.

An apparatus for acquiring seismic wave data includes a network of geophones and a seismic wave data receiving device coupled to the network and configured to receive the seismic wave data as an optical signal and process the seismic data in real time to provide locations and corresponding sizes of fractures in an earth formation. The network of geophones includes: a plurality of geophone channels, each channel having an array of geophones coupled to a field digitizer unit; an array of geophone patches having geophone channels connected in series by a metallic conductor; a plurality of geophone branches having a metallic conductor and a branch digitizer unit to connect geophone patches in series; a plurality of electrical to optical signal converters for converting signals received from branch digitizer units for transmission using an optical fiber; and a plurality of optical fiber segments for transmitting optical signals to the receiving device.

A method includes deploying a logging tool in a borehole formed in a subsurface formation. The logging tool has a transmitter and a receiver. The method includes emitting, by the transmitter, a signal into subsurface formation. The method includes detecting, by the receiver, a response to the signal being propagated through the subsurface formation. The method includes creating, from the response, a borehole image that includes distorted features representing bedding dips in the subsurface formation. The method includes correcting the distorted features, wherein correcting the distorted features comprises mapping points of a non-circular shape in the borehole image to points on a circular shape.

A method includes deploying a logging tool in a borehole formed in a subsurface formation. The logging tool has a transmitter and a receiver. The method includes emitting, by the transmitter, a signal into subsurface formation. The method includes detecting, by the receiver, a response to the signal being propagated through the subsurface formation. The method includes creating, from the response, a borehole image that includes distorted features representing bedding dips in the subsurface formation. The method includes correcting the distorted features, wherein correcting the distorted features comprises mapping points of a non-circular shape in the borehole image to points on a circular shape.

The present disclosure relates to a method that includes generating a first pulse at a first position along a geological formation with a plurality of antennae, wherein the first pulse comprises a Can-Purcell-Meiboom-Gill (CPMG) sequence, and wherein each antenna of the plurality of antennae is configured to generate NMR data via transmitting and receiving pulses into the geological formation.

The present disclosure describes a method for surveillance of a horizontal well, including: monitoring a first set of measurement data from a pulsed neutron tool and a second set of measurement data from an array tool, wherein: the first set of measurement data indicate a holdup of the second liquid globally inside the horizontal well, and the second set of measurement data show a plurality of velocities measured at a set of corresponding locations inside the horizontal well; and interpolating the first set of measurement data to identify an interface between the first liquid and the second liquid; establish an estimated holdup of the second liquid in the cross-section of the horizontal well; and combining the estimated holdup of the second liquid with velocities measured at locations inside the horizontal well that correspond to the second layer to generate a flow weighted estimate of the second liquid inside the horizontal well.

The present disclosure describes a method for surveillance of a horizontal well, including: monitoring a first set of measurement data from a pulsed neutron tool and a second set of measurement data from an array tool, wherein: the first set of measurement data indicate a holdup of the second liquid globally inside the horizontal well, and the second set of measurement data show a plurality of velocities measured at a set of corresponding locations inside the horizontal well; and interpolating the first set of measurement data to identify an interface between the first liquid and the second liquid; establish an estimated holdup of the second liquid in the cross-section of the horizontal well; and combining the estimated holdup of the second liquid with velocities measured at locations inside the horizontal well that correspond to the second layer to generate a flow weighted estimate of the second liquid inside the horizontal well.

This disclosure presents methods and processes to estimate a position parameter, an orientation parameter, a dip parameter, and a diameter parameter of an object or subterranean formation change proximate an active borehole. The object or formation can be an adjacent borehole. The parameters can be utilized by a geo-steering system or a well site job plan system to reduce an uncertainty surrounding or looking ahead of the active borehole to avoid a collision with the object or formation, to intercept the object or formation, or to place the active borehole in a more advantageous position. The parameters can be derived from collected component resistivity data that has been reconstructed utilizing a three-dimensional inversion algorithm. In some aspects, low resistivity data can be extracted to improve the estimating of the parameters. In some aspects, the process can be implemented in a downhole tool, in a surface system, or a combination thereof.

Techniques for calibration of a simulation of a subterranean region having complex fracture geometries. Calibration of indeterministic subsurface discrete fracture network models is performed via non-intrusive embedded discrete fracture modeling formulations applied in conjunction with well testing interpretation and numerical simulation. Subterranean fracture networks are characterized dynamically by embedded discrete fracture modeling to accurately and efficiently determine an optimal fracture model.