Abstract: In some implementations, a plurality of thermoelectric devices may be arranged to cool one or more components of a downhole drilling component during drilling operations. A current can be applied to one or more thermoelectric devices to generate a cooling effect. The thermoelectric devices can be located and arranged so that they cool some or all of a bottom hole assembly or components thereof, such as one or more sensors, batteries, processors, electrics, and the like. The thermoelectric devices also may be located and arranged to cool sensors, batteries, other downhole components, and/or drilling mud in a wellbore during drilling operations. A plurality of thermoelectric devices may be used to generate electric power downhole from a temperature difference. The electric power may be used to power sensors, processors, charge batteries, and be used by one or more downhole electric components, such as those in a bottom hold assembly.

Abstract: In some implementations, a plurality of thermoelectric devices may be arranged to cool one or more components of a downhole drilling component during drilling operations. A current can be applied to one or more thermoelectric devices to generate a cooling effect. The thermoelectric devices can be located and arranged so that they cool some or all of a bottom hole assembly or components thereof, such as one or more sensors, batteries, processors, electrics, and the like. The thermoelectric devices also may be located and arranged to cool sensors, batteries, other downhole components, and/or drilling mud in a wellbore during drilling operations. A plurality of thermoelectric devices may be used to generate electric power downhole from a temperature difference. The electric power may be used to power sensors, processors, charge batteries, and be used by one or more downhole electric components, such as those in a bottom hold assembly.

Abstract: A system and method of drilling a wellbore to a target may include measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations may be determined. Corrections may be applied to the measured attitude at one or both of the survey stations such that an estimated well path joining the survey stations indicates the determined actual change in wellbore position between the two survey stations.

Abstract: A method of drilling a wellbore to a target includes measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations is determined. Corrections are applied to the measured attitude at one or both of the survey stations such that a modeled well path joining the survey stations reflects the determined actual change in wellbore positon between the two survey stations.

Abstract: A method of drilling a wellbore to a target includes measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations is determined. Corrections are applied to the measured attitude at one or both of the survey stations such that a modeled well path joining the survey stations reflects the determined actual change in wellbore positon between the two survey stations.

Abstract: A system and method of drilling a wellbore to a target may include measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations may be determined. Corrections may be applied to the measured attitude at one or both of the survey stations such that an estimated well path joining the survey stations indicates the determined actual change in wellbore position between the two survey stations.

Abstract: A method of validating a directional survey includes measuring the gravity and magnetic field vectors using a surveying tool and computing an overall statistical distance of the measurement. The statistical distance may be calculated from reference values associated with the surveying tool using corresponding surveying tool codes with error values. In a further aspect, an error covariance matrix may be used to determine whether the new errors in a survey are consistent or not with errors from one or more previous surveys.

Abstract: A method of validating a directional survey includes measuring the gravity and magnetic field vectors using a surveying tool and computing an overall statistical distance of the measurement. The statistical distance may be calculated from reference values associated with the surveying tool using corresponding surveying tool codes with error values. In a further aspect, an error covariance matrix may be used to determine whether the new errors m a survey are consistent or not with errors from one or more previous surveys.

Abstract: A method and system for geosteering may generate a misfit function using a spline function. The misfit function may be used to accurately map errors or differences between TVD-based measurement data for one or more reference wells and MD-based measurement data collected during drilling of a subject well, in order to accurately determine a stratigraphic location of the subject well.

Abstract: A method of drilling a wellbore to a target includes measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations is determined. Corrections are applied to the measured attitude at one or both of the survey stations such that a modeled well path joining the survey stations reflects the determined actual change in wellbore positon between the two survey stations.

Abstract: A method of validating a directional survey includes measuring the gravity and magnetic field vectors using a surveying tool and computing an overall statistical distance of the measurement. The statistical distance may be calculated from reference values associated with the surveying tool using corresponding surveying tool codes with error values. In a further aspect, an error covariance matrix may be used to determine whether the new errors m a survey are consistent or not with errors from one or more previous surveys.

Abstract: A system and method of drilling a wellbore to a target may include measuring attitudes at two adjacent survey stations along a wellbore using a downhole surveying tool. An actual change in wellbore position over a survey leg linking the two survey stations may be determined. Corrections may be applied to the measured attitude at one or both of the survey stations such that an estimated well path joining the survey stations indicates the determined actual change in wellbore position between the two survey stations.