Abstract: Contamination estimation of a mud filtrate or reservoir sample requires a robust handle on the properties of mud filtrate at downhole conditions. Coupling acquired data with downhole measured data provides a robust estimation of contamination by encompassing the entire available data. Downhole density of the mud filtrate sample may be estimated based on a characteristic of the mud filtrate sample. A density of a formation fluid of the reservoir may be determined using a formation tester tool. The contamination of the formation fluid may be estimated based on the clean fluid density and the estimated mud filtrate density by, for example, using a material balance equation or ratio. An estimated pump-out time for the formation fluid may be determined based on the estimated contamination and a trend of the estimated contamination of the formation fluid.

Abstract: A location of a cut and an amount of force to be used in a pull operation for a plug & abandonment (P&A) operation can be determined. Measurements of at least one characteristic of fluids and solids disposed in an annulus defined between a casing and a wall of a wellbore can be received. A total fluid and solid friction force drag can be determined using hydrostatic force that is determined from the measurements. A mechanical friction force drag can be determined based on a weight of the casing. The mechanical friction force drag and the total fluid and solid friction force drag can be used to determine a friction factor. The friction factor can be used to determine a depth location at which to cut the casing and a pull force for pulling the casing from the wellbore in the P&A operation.

Abstract: A location of a cut and an amount of force to be used in a pull operation for a plug & abandonment (P&A) operation can be determined. Measurements of at least one characteristic of fluids and solids disposed in an annulus defined between a casing and a wall of a wellbore can be received. A total fluid and solid friction force drag can be determined using hydrostatic force that is determined from the measurements. A mechanical friction force drag can be determined based on a weight of the casing. The mechanical friction force drag and the total fluid and solid friction force drag can be used to determine a friction factor. The friction factor can be used to determine a depth location at which to cut the casing and a pull force for pulling the casing from the wellbore in the P&A operation.

Abstract: A system includes a pressure transient analysis test tool with flow analysis components and at least one pressure sensor. The pressure transient analysis test tool collects pressure measurements for at least one target position in a borehole as a function of time and fluid flow rate. The system also includes at least one processor that receives saturation analysis results and porosity analysis results related to each target position. The processor estimates relative permeability values based at least in part on the pressure measurements, the saturation analysis results, and the porosity analysis results.

Abstract: Contamination estimation of a mud filtrate or reservoir sample requires a robust handle on the properties of mud filtrate at downhole conditions. Coupling acquired data with downhole measured data provides a robust estimation of contamination by encompassing the entire available data. Downhole density of the mud filtrate sample may be estimated based on a characteristic of the mud filtrate sample. A density of a formation fluid of the reservoir may be determined using a formation tester tool. The contamination of the formation fluid may be estimated based on the clean fluid density and the estimated mud filtrate density by, for example, using a material balance equation or ratio. An estimated pump-out time for the formation fluid may be determined based on the estimated contamination and a trend of the estimated contamination of the formation fluid.

Abstract: Contamination estimation of a mud filtrate or reservoir sample requires a robust handle on the properties of mud filtrate at downhole conditions. Coupling acquired data with downhole measured data provides a robust estimation of contamination by encompassing the entire available data. Downhole density of the mud filtrate sample may be estimated based on a characteristic of the mud filtrate sample. A density of a formation fluid of the reservoir may be determined using a formation tester tool. The contamination of the formation fluid may be estimated based on the clean fluid density and the estimated mud filtrate density by, for example, using a material balance equation or ratio. An estimated pump-out time for the formation fluid may be determined based on the estimated contamination and a trend of the estimated contamination of the formation fluid.

Abstract: A computer accepts dead-oil properties of a reservoir fluid sampled from a well. The dead-oil properties are the measured composition of the reservoir fluid after volatile components of the reservoir have substantially vaporized. The computer analyzes the dead-oil properties and a constraint to produce estimated live-oil properties of the reservoir fluid. The live-oil properties are the composition of the reservoir before the volatile components have substantially vaporized. The computer uses the estimated live-oil properties to make a decision regarding the well.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to advance a geological formation probe with a surrounding pad to seal the pad against a borehole wall, to adjust the size of the area associated with a fluid flow inlet of the probe, where the size of the inlet area is selectably and incrementally variable, and to draw fluid into the fluid flow inlet by activating at least one pump coupled to at least one fluid passage in the probe.

Abstract: Various logging-while-drilling (LWD) systems and methods provide resistivity logging coupled with deep detection of elongated anomalies at acute angles, enabling effective geosteering without disrupting drilling operations and without requiring intervention in the operations of the existing well. One LWD system embodiment employs a tool having tilted antennas as the transmitter and the receiver, where at least one of the antennas is placed in the vicinity of the bit, making it possible to detect existing wells at distances of 50-100 feet. In some cases, the detection distance is increased by enhancing the visibility of the existing well using a contrast fluid treatment on target well, either to fill the bore or to surround the well with treated cement or fluids that invade the formation. At least one inversion method separates the inversion of formation parameters from the inversion of parameters specifying distance, direction, and orientation of the existing well.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to advance a sampling and guard probe (100) with a surrounding sealing pad (108) against a borehole wall, to adjust the size of the area associated with a fluid flow inlet of the probe, where the size of the inlet area (104) is selectably and incrementally variable, and to draw fluid into the fluid flow inlet by activating at least one pump (344) coupled to at least one fluid passage (128) in the probe. Additional apparatus, systems, and methods are disclosed.

Abstract: In some embodiments, an apparatus and a system, as well as a method an article, may operate to move a borehole seal in space with respect to the wall of a borehole while monitoring borehole seal contact quality data, which may comprise borehole seal contact pressure data and acoustic data. Operations may further include adjusting the movement of the borehole seal based on the borehole seal contact quality data. Additional apparatus, systems, and methods are disclosed.

Abstract: A computer accepts dead-oil properties of a reservoir fluid sampled from a well. The dead-oil properties are the measured composition of the reservoir fluid after volatile components of the reservoir have substantially vaporized. The computer analyzes the dead-oil properties and a constraint to produce estimated live-oil properties of the reservoir fluid. The live-oil properties are the composition of the reservoir before the volatile components have substantially vaporized. The computer uses the estimated live-oil properties to make a decision regarding the well.

Abstract: In some embodiments, an apparatus and a system, as well as a method an article, may operate to move a borehole seal in space with respect to the wall of a borehole while monitoring borehole seal contact quality data, which may comprise borehole seal contact pressure data and acoustic data. Operations may further include adjusting the movement of the borehole seal based on the borehole seal contact quality data. Additional apparatus, systems, and methods are disclosed.

Abstract: Various logging-while-drilling (LWD) systems and methods provide resistivity logging coupled with deep detection of elongated anomalies at acute angles, enabling effective geosteering without disrupting drilling operations and without requiring intervention in the operations of the existing well. One LWD system embodiment employs a tool having tilted antennas as the transmitter and the receiver, where at least one of the antennas is placed in the vicinity of the bit, making it possible to detect existing wells at distances of 50-100 feet. In some cases, the detection distance is increased by enhancing the visibility of the existing well using a contrast fluid treatment on target well, either to fill the bore or to surround the well with treated cement or fluids that invade the formation. At least one inversion method separates the inversion of formation parameters from the inversion of parameters specifying distance, direction, and orientation of the existing well.