A method of estimating a position of a well path within a subsurface formation of the Earth, the method comprising determining a well path estimate using navigation measurements from a downhole tool and a position estimate derived from seismic data. A method of geosteering comprising: estimating a position of the well path and controlling a drill bit in response to the estimated position of the well path to follow a desired well trajectory.

A method of estimating a position of a well path within a subsurface formation of the Earth, the method comprising determining a well path estimate using navigation measurements from a downhole tool and a position estimate derived from seismic data. A method of geosteering comprising: estimating a position of the well path and controlling a drill bit in response to the estimated position of the well path to follow a desired well trajectory.

The way in which a fiber optic cable is wrapped around a casing string in a wellbore can be modeled using information from downhole sensor devices. For example, a system can include a fiber optic cable located along a length of a wellbore. The system can also include sensor devices located near the fiber optic cable at various depths to transmit acoustic signals indicating depths and orientations of segments of the fiber optic cable. The system can build a model describing how the fiber optic cable is positioned around the casing string based on the acoustic signals transmitted from the sensor devices. The system can also determine a target position for a perforating gun to perform a perforation operation through the casing string that avoids damaging the fiber optic cable. The system can output the target position for the perforating gun to an electronic device to facilitate the perforation operation.

The way in which a fiber optic cable is wrapped around a casing string in a wellbore can be modeled using information from downhole sensor devices. For example, a system can include a fiber optic cable located along a length of a wellbore. The system can also include sensor devices located near the fiber optic cable at various depths to transmit acoustic signals indicating depths and orientations of segments of the fiber optic cable. The system can build a model describing how the fiber optic cable is positioned around the casing string based on the acoustic signals transmitted from the sensor devices. The system can also determine a target position for a perforating gun to perform a perforation operation through the casing string that avoids damaging the fiber optic cable. The system can output the target position for the perforating gun to an electronic device to facilitate the perforation operation.

A method can include, using a downhole tool, acquiring ultrasonic echo data of a borehole, where the ultrasonic echo data include echoes representative of material and borehole geometry responsive to reflection of ultrasonic energy that has a wide-band frequency range; filtering the ultrasonic echo data using at least one selected filter for multi-band frequency filtering corresponding to different frequency ranges of the wide-band frequency range to generate filtered data; and processing the filtered data to generate attribute values representative of physical characteristics the material, the borehole geometry, or the material and the borehole geometry.

A method can include, using a downhole tool, acquiring ultrasonic echo data of a borehole, where the ultrasonic echo data include echoes representative of material and borehole geometry responsive to reflection of ultrasonic energy that has a wide-band frequency range; filtering the ultrasonic echo data using at least one selected filter for multi-band frequency filtering corresponding to different frequency ranges of the wide-band frequency range to generate filtered data; and processing the filtered data to generate attribute values representative of physical characteristics the material, the borehole geometry, or the material and the borehole geometry.

A high-temperature miniaturized resonant gyroscope, which comprises a resonator, a circuit board, a piezoelectric element, a supporting base, a shell and a binding post, wherein the resonator is arranged in the shell and connected with the supporting base, the piezoelectric element is connected with the binding post through a metal conductor, and key process points of internal elements of the gyroscope are fixedly connected by high-temperature materials and high-temperature processes. The gyroscope is a small-sized gyroscope capable of working at a high temperature; the present disclosure also provides an inertial navigation system, which comprises a triaxial gyroscope, a triaxial accelerometer and a damper, wherein the gyroscope is fixedly connected with the damper, and the gyroscope adopts the high-temperature resonant gyroscope. A drilling measurement system and a measurement method.

A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

A system for drilling a well may be adapted to process signals received from a fiber optic cable located in the casing of a previously drilled well or wells. The fiber optic cable may act as a distributed sensor receiving acoustic signals generated during the drilling of the well, and the system may be programmed to process the signals from the fiber optic cable to locate the borehole of the well being drilled, including its location relative to the previously drilled well or well. The system may be used to automatically update a well plan for the well being drilled responsive to information about the location of the borehole and also may be used to automatically adjust one or more drilling parameters or drilling operations responsive to the location of the second well borehole.