A drilling system for drilling a borehole. The drilling system may include a drill string, a drill bit coupled to the drill string, a mud motor coupled to the drill string uphole of the drill bit and operable to rotate the drill bit via a driveshaft, a bearing assembly coupled to a downhole end of the mud motor and operable to support the driveshaft, and a rotary steerable system (“RSS”) operable to push the drill bit in a desired direction via pads extended using drilling fluid flowing through the driveshaft and to the RSS. The bearing assembly may include bearings positioned circumferentially around a bore of the bearing assembly, a fluid flowpath through the bearings to allow drilling fluid to pass through the bearings, and a choke assembly positioned in the fluid flowpath and operable to restrict a flow of the drilling fluid through the fluid flowpath.

Systems and methods for determining azimuth of a wellbore while drilling. A method of drilling a wellbore that includes rotating a drill bit to extend the wellbore into a subterranean formation. The method may further include measuring magnetic toolface with a first magnetometer while rotating the drill bit. The method may further include obtaining a cross-axial magnetic field measurement. The method may further include determining azimuth at a point in the wellbore using at least the magnetic toolface and the cross-axial magnetic field measurement. The method may further include using the azimuth as feedback in the drilling the wellbore.

Techniques for determining a wellbore drilling path includes identifying input seismic data associated with a subterranean zone that includes a wellbore drilling target. The input seismic data includes primary seismic events and multiple seismic events. The input seismic data is processed to remove the multiple seismic events and at least one of the primary seismic events from the input seismic data. An orthogonalization of the processed input seismic data is performed to recover the at least one primary seismic event into a seismic image of the subterranean zone that excludes at least a portion of the multiple seismic events. A wellbore path is determined from a terranean surface toward the wellbore drilling target for a drilling geo-steering system based on the seismic image of the subterranean zone.

Techniques for determining a wellbore drilling path includes identifying input seismic data associated with a subterranean zone that includes a wellbore drilling target. The input seismic data includes primary seismic events and multiple seismic events. The input seismic data is processed to remove the multiple seismic events and at least one of the primary seismic events from the input seismic data. An orthogonalization of the processed input seismic data is performed to recover the at least one primary seismic event into a seismic image of the subterranean zone that excludes at least a portion of the multiple seismic events. A wellbore path is determined from a terranean surface toward the wellbore drilling target for a drilling geo-steering system based on the seismic image of the subterranean zone.

A method for drilling a subterranean wellbore includes rotating a drill string in the subterranean wellbore. The drill string includes a drill collar, a drill bit, and survey sensors (e.g., a triaxial accelerometer set and a triaxial magnetometer set) deployed therein. The triaxial accelerometer set and the triaxial magnetometer set make corresponding accelerometer and magnetometer measurements while drilling (rotating). These measurements are synchronized to obtain synchronized accelerometer and magnetometer measurements and then further processed to compute at least an inclination and an azimuth of the subterranean wellbore while drilling. The method may further optionally include changing a direction of drilling the subterranean wellbore in response to the computed inclination and azimuth.

A method for drilling a subterranean wellbore includes rotating a drill string in the subterranean wellbore. The drill string includes a drill collar, a drill bit, and survey sensors (e.g., a triaxial accelerometer set and a triaxial magnetometer set) deployed therein. The triaxial accelerometer set and the triaxial magnetometer set make corresponding accelerometer and magnetometer measurements while drilling (rotating). These measurements are synchronized to obtain synchronized accelerometer and magnetometer measurements and then further processed to compute at least an inclination and an azimuth of the subterranean wellbore while drilling. The method may further optionally include changing a direction of drilling the subterranean wellbore in response to the computed inclination and azimuth.

A controllable drilling head for a drill string for ground drilling with a drilling head tip and a locating pin that carries the drilling head tip, the drilling head tip having a bore slanted to the longitudinal axis and the locating pin being angled to the longitudinal axis, wherein the drilling head tip can rotate on the locating pin, the drilling head tip and the locating pin being arranged in a first angular position relative to one another for straight drilling, and the drilling head tip and the locating pin being arranged in a second angular position relative to one another for drilling that deviates from straight drilling.

A system and method for determining an uncertainty of a distance to bed boundary (DTBB) inversion of a geologic formation. The system or method includes receiving logging data from a borehole tool, performing a first DTBB inversion using the logging data to calculate first DTBB solutions, adding quantified noise to the logging data to produce an adjusted signal, performing a second DTBB inversion using the adjusted signal to calculate second DTBB solutions, comparing the first DTBB solutions to the second DTBB solutions to determine an uncertainty of the first DTBB solutions based on a relationship of the quantified noise and the difference between the first DTBB solutions and the second DTBB solutions.

A system and method for determining an uncertainty of a distance to bed boundary (DTBB) inversion of a geologic formation. The system or method includes receiving logging data from a borehole tool, performing a first DTBB inversion using the logging data to calculate first DTBB solutions, adding quantified noise to the logging data to produce an adjusted signal, performing a second DTBB inversion using the adjusted signal to calculate second DTBB solutions, comparing the first DTBB solutions to the second DTBB solutions to determine an uncertainty of the first DTBB solutions based on a relationship of the quantified noise and the difference between the first DTBB solutions and the second DTBB solutions.

A high efficiency smart steering drilling system includes a smart push force application tool and a centralizer. The centralizer is at an end close to a drill bit. The smart push force application tool is at an end away from the drill bit and includes a push force application wing rib having a telescoping function. The smart push force application tool is capable of automatically measuring an inclination angle and an azimuth angle and comparing the inclination angle and the azimuth angle with design values so as to control the push force application wing rib to output a push force in a telescopic manner based on a difference between the measured values and the design values and applying a push force to the drill bit. The drilling system achieves combined deflection under double action of drill bit push and pointing, greatly improving the deflection capability.