Abstract: In one aspect, an apparatus for use in a wellbore is provided that in one embodiment includes a sensor having a plurality of spaced conductive contact elements, a sensing member that moves by gravity and contacts at least two contact elements in the plurality of contact elements to create an electrical short between such at least two contact elements and a circuit coupled to the contact elements configured to generate electrical signals in response to the electrical short between the contact elements.

Abstract: Autonomous control of a wellbore tool is provided by programming a memory module of a processor with a database having data relating to a selected parameter of interest; conveying a sensor and the processor along the wellbore; and activating the wellbore tool if the processor determines that a measurement provided by the sensor correlates with the database data. The processor may correlate the sensor measurements with a predetermined pattern associated with the data, a preset value, and/or a preset range of values. Well tool activation may occur when the processor finds: a substantial match between a predetermined pattern and at least one measured value; a present value and at least one measured value, and/or a preset range of values and at least one measured range of values. Also, activating the well tool may occur only if a measurement from a second sensor meets a preset criteria.

Abstract: A method to correct for a systematic error of a sensor having a plurality of accelerometers configured to measure gravitational acceleration, the method including: rotating the plurality of accelerometers about a first axis; obtaining a first set of calibration measurements from the plurality of accelerometers from the rotation about the first axis; determining a first systematic error for each accelerometer in the plurality using the first set of calibration measurements; and removing the first systematic error from sensor measurements to correct for the systematic error.

Abstract: A method for determining depth in a wellbore uses inertial navigation in conjunction with a database having one or more measured parameters correlated with depth. The measured parameter may be the lengths of stands forming a drill string, prior survey data relating to a naturally occurring feature such as formation lithology, or data relating to a human made feature such as collars in a casing string. The downhole processor may use accelerometer measurements to calculate a measured depth of a BHA and access the database to retrieve a predicted depth that corresponds with one or more sensor measurements (e.g., motion indicating the addition of a stand to a drill string). Thereafter, if the downhole processor determines that the predicted depth is in agreement with the calculated depth, the processor stores the predicted depth and/or associates the predicted depth with directional surveys taken along the wellbore.

Abstract: A method for measuring true vertical depth in a borehole, the method including: measuring gravitational acceleration in the borehole; and determining the true vertical depth from the measurement.

Abstract: The Emergency Disaster Temporary Rapid Deployment Oil Spill Reclamation Pyramid and Pyramid with Chute and Flotation Collar is a totally new concept to the offshore oil industry. Nothing of this unique, new concept has ever been conceived, manufactured or deployed in the history of the offshore oil drilling industry. It is a revolutionary concept that will have a dramatic impact on the problems with the environment, the fish and wildlife, the local and national economy, and the health and welfare of the citizens of the United States from the time of this application into the future. The Emergency Disaster Temporary Rapid Deployment Oil Spill Reclamation Pyramid and Pyramid with Chute and Flotation Collar is a conceptual method of arresting the oil from an off-shore oil spill such as the DEEPWATER HORIZON.

Abstract: A two-axis gyroscope used on a bottom hole assembly can be used for determining a rate of rotation about the rotational axis of a BHA. The method takes advantage of possible misalignment of at least one axis of the two axis gyroscope from orthogonality with respect to the rotational axis of the BHA, resulting in the misaligned gyro being sensitive to BHA rotation.

Abstract: A photodiode whose long-wavelength cutoff is in the short-wavelength range (preferably, between ultraviolet and yellowish-green) having reduced temperature sensitivity is used in downhole applications. It may be matched with scintillation devices having an output matched to the response curve of the photodiode for use with nuclear logging devices. The photodiode may also be used in gyroscopes in which light from an LED matched to the photodiode is reflected from a spinning mass.

Abstract: A method to correct for a systematic error of a sensor having a plurality of accelerometers configured to measure gravitational acceleration, the method including: rotating the plurality of accelerometers about a first axis; obtaining a first set of calibration measurements from the plurality of accelerometers from the rotation about the first axis; determining a first systematic error for each accelerometer in the plurality using the first set of calibration measurements; and removing the first systematic error from sensor measurements to correct for the systematic error.

Abstract: A method for surveying a formation includes conveying a survey instrument into the wellbore; measuring one or more parameters of interest relating to a wellbore tubular in the wellbore; and operating the survey instrument after the measured parameter of interest indicates that the wellbore tubular is being tripped out of the wellbore.

Abstract: An instrument for measuring gravitational acceleration, the instrument including: a plurality of accelerometers disposed about a three-dimensional structure, the plurality of accelerometers providing output used for measuring the gravitational acceleration; wherein each accelerometer in the plurality is implemented by at least one of a micro-electromechanical system (MEMS) and a nano-electromechanical system (NEMS).

Abstract: A method for measuring true vertical depth in a borehole, the method including: measuring gravitational acceleration in the borehole; and determining the true vertical depth from the measurement.

Abstract: Autonomous control of a wellbore tool is provided by programming a memory module of a processor with a database having data relating to a selected parameter of interest; conveying a sensor and the processor along the wellbore; and activating the wellbore tool if the processor determines that a measurement provided by the sensor correlates with the database data. The processor may correlate the sensor measurements with a predetermined pattern associated with the data, a preset value, and/or a preset range of values. Well tool activation may occur when the processor finds: a substantial match between a predetermined pattern and at least one measured value; a present value and at least one measured value, and/or a preset range of values and at least one measured range of values. Also, activating the well tool may occur only if a measurement from a second sensor meets a preset criteria.

Abstract: A method for determining depth in a wellbore uses inertial navigation in conjunction with a database having one or more measured parameters correlated with depth. The measured parameter may be the lengths of stands forming a drill string, prior survey data relating to a naturally occurring feature such as formation lithology, or data relating to a human made feature such as collars in a casing string. The downhole processor may use accelerometer measurements to calculate a measured depth of a BHA and access the database to retrieve a predicted depth that corresponds with one or more sensor measurements (e.g., motion indicating the addition of a stand to a drill string). Thereafter, if the downhole processor determines that the predicted depth is in agreement with the calculated depth, the processor stores the predicted depth and/or associates the predicted depth with directional surveys taken along the wellbore.

Abstract: A nuclear sensor on a bottomhole assembly (BHA) makes measurements of a property of an earth formation during continued rotation of the BHA. Magnetometers that are susceptible to bias error are deployed on the BHA to make measurements of the magnetic toolface angle. A processor separates the sensor measurements into azimuthal sectors while compensating for inherent time delays in the electronics, non-uniform rotation, and bias.

Abstract: A two-axis gyroscope used on a bottom hole assembly can be used for determining a rate of rotation about the rotational axis of a BHA. The method takes advantage of possible misalignment of at least one axis of the two axis gyroscope from orthogonality with respect to the rotational axis of the BHA, resulting in the misaligned gyro being sensitive to BHA rotation.

Abstract: A two-axis gyroscope used on a bottom hole assembly can be used for determining a rate of rotation about the rotational axis of a BHA. The method takes advantage of possible misalignment of at least one axis of the two axis gyroscope from orthogonality with respect to the rotational axis of the BHA, resulting in the misaligned gyro being sensitive to BHA rotation.

Abstract: This invention provides a measurement-while-drilling (MWD) downhole assembly for use in drilling boreholes which utilizes directional formation evaluation devices on a rotating assembly in conjunction with toolface orientation sensors. The data from the toolface orientation sensors are analyzed by a processor and toolface angle measurements are determined at defined intervals. Formation evaluation sensors operate substantially independently of the toolface orientation sensors and measurements of the formation evaluation sensors are analyzed in combination with the determined toolface angle to obtain formation parameters.

Abstract: A photodiode whose long-wavelength cutoff is in the short-wavelength range (preferably, between ultraviolet and yellowish-green) having reduced temperature sensitivity is used in downhole applications. It may be matched with scintillation devices having an output matched to the response curve of the photodiode for use with nuclear logging devices. The photodiode may also be used in gyroscopes in which light from an LED matched to the photodiode is reflected from a spinning mass.

Abstract: This invention provides a measurement-while-drilling (MWD) downhole assembly for use in drilling boreholes which utilizes directional formation evaluation devices on a rotating assembly in conjunction with toolface orientation sensors. The data from the toolface orientation sensors are analyzed by a processor and toolface angle measurements are determined at defined intervals. Formation evaluation sensors operate substantially independently of the toolface orientation sensors and measurements of the formation evaluation sensors are analyzed in combination with the determined toolface angle to obtain formation parameters.