A directional filter for processing full-tensor gradiometer data is described. The filter processes input data using a method comprising receiving geophysical data collected based on characteristics of geographic features in an environment, and applying a directional filter to the received geophysical data in a first instance so as to provide first filtered data. A filtering direction of the directional filter is determined based on properties in the received geophysical data. The method also includes updating the filtering direction based on properties in the first filtered data, applying the directional filter to the received geophysical data in a subsequent instance using the updated filtering direction so as to provide subsequent filtered data, and based on the updated filtering direction having a subsequent update less than a threshold, outputting directionally filtered data. The subsequent update is determined due to properties in the subsequent filtered data output from the subsequent instance.

A directional filter for processing full-tensor gradiometer data is described. The filter processes input data using a method comprising receiving geophysical data collected based on characteristics of geographic features in an environment, and applying a directional filter to the received geophysical data in a first instance so as to provide first filtered data. A filtering direction of the directional filter is determined based on properties in the received geophysical data. The method also includes updating the filtering direction based on properties in the first filtered data, applying the directional filter to the received geophysical data in a subsequent instance using the updated filtering direction so as to provide subsequent filtered data, and based on the updated filtering direction having a subsequent update less than a threshold, outputting directionally filtered data. The subsequent update is determined due to properties in the subsequent filtered data output from the subsequent instance.

A geopositioning system. The geopositioning system includes an accelerometer including three sensing axes, a gyroscope including three sensing axes, and a magnetometer including three sensing axes, and a processing circuit. The processing circuit is configured to calculate a location of the geopositioning system as a latitude, longitude, and altitude with respect to the Earth.

Airborne gravity measurements may be added to the collection of airborne LiDAR so that it may be used to produce a digital elevation model (DEM), which may be used along with gravity data to produce an improved geoid, which may be used to produce an improved DEM based on the improved orthometric heights. A computing device may be configured to receive airborne navigation, gravity and LiDAR data, generate position information based on the navigation data, generate gravity field information based on the gravity data and the position information, generate orthometric height information based on the LiDAR data and the position information, and generate a geoid based on the gravity field and orthometric height information. The computing device may also generate a geoid model based on the gravity field and an existing DEM, and generate the orthometric height information based on the LiDAR data, position information, and geoid model.

A method of estimating one or both of compaction or subsidence of a subterranean formation with gravity measurements. The free air gradient at surface is measured and compared with gravity measured in a borehole that intersects the formation. At a later point in time, values for gravity are re-measured, differences between the measured values at the initial point in time, and the later point in time are estimated. The differences are used to estimate the compaction or subsidence. A gravimeter can be used for measuring gravity, markers in the formation can be used in conjunction with the gravimeter.

A method of estimating one or both of compaction or subsidence of a subterranean formation with gravity measurements. The free air gradient at surface is measured and compared with gravity measured in a borehole that intersects the formation. At a later point in time, values for gravity are re-measured, differences between the measured values at the initial point in time, and the later point in time are estimated. The differences are used to estimate the compaction or subsidence. A gravimeter can be used for measuring gravity, markers in the formation can be used in conjunction with the gravimeter.

Disclosed is a method for generating an estimation of earth's gravity. The method includes: obtaining one or more acceleration data values and one or more orientation data values over a period of time; generating magnitude of orientation change from the orientation data values; determining a stability value based on the acceleration data values and the magnitude of orientation change; comparing the determined stability value to a threshold value; and generating an estimation of earth's gravity over the period of time on the basis of the acceleration data values if the comparison indicates that the determined stability value is below the threshold value. Also disclosed is an apparatus implementing the method.

Disclosed is a method for generating an estimation of earth's gravity. The method includes: obtaining one or more acceleration data values and one or more orientation data values over a period of time; generating magnitude of orientation change from the orientation data values; determining a stability value based on the acceleration data values and the magnitude of orientation change; comparing the determined stability value to a threshold value; and generating an estimation of earth's gravity over the period of time on the basis of the acceleration data values if the comparison indicates that the determined stability value is below the threshold value. Also disclosed is an apparatus implementing the method.

An airborne gravity-based transducer is disclosed as two embodiments with similar physical structures but different operating principles. The first design includes a particle acting as an active interface characterized by internal vibrations relating to its de Broglie wave, a resonant cavity for trapping the particle, and a phonon-wave source wherein the de Broglie and phonon waves interact over a junction area. In the second design, mechanical displacements between the transducer elements can be monitored through electromechanical transduction. Both designs include a power source and a biasing circuit for producing an electrical current across the junction, and a sensing system for measuring voltage. Both designs are capable of cancelling slowly-varying gravitational acceleration due to dynamic interaction in motion with the gravitational field and responding to small-scale gravity anomalies. The transducer can be utilized in hydrocarbon exploration to provide information on areas conducive to fluid entrapment in the sedimentary column.

A method includes collecting a first set of borehole gravity data at a first time step along a length of a first wellbore and collecting a second set of borehole gravity data at the first time step along a length of a second wellbore. The method also includes interpolating a third set of borehole gravity data at the first time step in an area between the first wellbore and the second wellbore using the first and the second sets of borehole gravity data. Further, the method includes determining a first fluid saturation and a fluid saturation change over time in a reservoir containing the first wellbore and the second wellbore using the first set, the second set, and the third set. Moreover, the method includes controlling wellbore production operations or wellbore injection operations at the first wellbore based on the fluid saturation change.