Abstract: A well cleaning tool includes a positioning device configured to control a position of the well cleaning tool within a well, a rotatable brush assembly configured to scrape a wall of the well, a capture device configured to catch debris dislodged from the wall by the rotatable brush assembly, and a fluid delivery assembly configured to deliver a cleaning fluid to the well.

Abstract: A well cleaning tool includes a positioning device configured to control a position of the well cleaning tool within a well, a rotatable brush assembly configured to scrape a wall of the well, a capture device configured to catch debris dislodged from the wall by the rotatable brush assembly, and a fluid delivery assembly configured to deliver a cleaning fluid to the well.

Abstract: A method of cleaning a well includes flowing well fluid within the well while running a cleaning tool into the well, injecting the well fluid with a fluid thickening agent through multiple nozzles of the well cleaning tool to form thickened well fluid, dislodging metallic debris and non-metallic debris accumulated along a wall of the well with multiple brushes of the cleaning tool, carrying the non-metallic debris out of the well with the thickened well fluid, and capturing the metallic debris at a capture device of the cleaning tool.

Abstract: A system includes a bottom hole assembly and a core sampling tool. The bottom hole assembly includes a housing and a drill bit coupled to the housing. The core sampling tool includes a first compartment positioned within the housing, the first compartment including a motor; a second compartment positioned within the housing and radially spaced apart from the first compartment, the second compartment including a coring bit; and a flexible drilling shaft extending between and coupled to the motor and the coring bit.

Abstract: Systems and methods include a computer-implemented method for predicting fluid holdups along the borehole or the pipe on surface and to perform fluid typing and fluid properties characterization. Acoustic waves are transmitted by an array of acoustic wave transducers. Each transducer is configured to transmit acoustic waves at a different frequency. The acoustic waves are received by an array of acoustic wave receivers fixed on the bow centralizer on the tool used in the borehole. Each receiver is configured to receive only the given frequency of a given transducer, forming a receiver-transducer pair for the given frequency. Acoustic speeds measured at each given frequency and analyzed. A model is generated based on the analyzing. The model is configured to predict fluid holdups across the borehole and to perform fluid typing and fluid properties characterization in one phase, two phase, and three phase applications of gas, oil, and water.

Abstract: A system includes a bottom hole assembly and a core sampling tool. The bottom hole assembly includes a housing and a drill bit coupled to the housing. The core sampling tool includes a first compartment positioned within the housing, the first compartment including a motor; a second compartment positioned within the housing and radially spaced apart from the first compartment, the second compartment including a coring bit; and a flexible drilling shaft extending between and coupled to the motor and the coring bit.

Abstract: A wellbore tool includes a body having a longitudinal axis and an outer circumferential surface. The wellbore tool includes moveable arms, housings, actuators, a temperature sensor, a pressure sensor, and a heat source, such as a microwave source. Each moveable arm is coupled to a respective actuator and a respective housing. Each actuator is configured to move the respective moveable arm. The temperature sensor is configured to measure a temperature of the subterranean formation. The pressure sensor is configured to measure a pressure of the subterranean formation. The microwave source is configured to generate microwave radiation. Methods of analyzing acquired transient temperature and transient pressure data for formation evaluation are also described.

Abstract: The disclosure provides methods of measuring an intrinsic CO ratio in a geological formation by disposing, proximate the formation, a petrophysical tool including at least one gamma-ray detector, reading a carbon gamma-ray peak for the geological formation and an oxygen gamma-ray peak for the geological formation, determining a measured CO ratio of the geological formation from the carbon gamma-ray peak and the oxygen gamma-ray peak, and correcting the measured CO ratio by applying a corrective algorithm specific for the petrophysical tool or the type of petrophysical tool to obtain an intrinsic CO ratio of the geological formation. The corrective algorithm is derived by a mathematical analysis of measured CO ratios of a sample with a known intrinsic CO ratio using the same petrophysical tool or a petrophysical tool representative of a same type of petrophysical tool. Additional methods and systems using this method are provided.

Abstract: Embodiments provide techniques for using data from a select set of wells to develop correlations between surface-measured properties, downhole coring parameters, and properties typically determined from subsurface measurements (e.g., from logging tool responses, core analysis, or other subsurface measurements). When new wells are drilled, the surface data acquired while drilling and coring parameters used downhole may be used as an input to these correlations in order to predict properties associated with subsurface measurements.

Abstract: A formation fluid sampling tool includes a housing, and at least one sampling probe proximate an external surface of the housing. The at least one sampling probe includes an opening sized and positioned to receive one or more heated formation fluids, and a plurality of heating elements arranged concentrically around the opening and configured to conductively heat a subterranean formation through an external surface of the sampling probe.

Abstract: Provided are techniques for saturation logging a hydrocarbon well in a hydrocarbon reservoir. The techniques including conducting a pulsed neutron (PN) logging of the well to generate a carbon/oxygen (C/O) log, conducting a nuclear magnetic resonance (NMR) logging of the well to generate a viscosity log, conducting a temperature logging of the well to generate a temperature log, determining a relationship of oil API gravity to viscosity and temperature for the reservoir, determining an oil API gravity log for the well based on the viscosity log, the temperature log, and the relationship of oil API gravity to viscosity and temperature, determining, based on the oil API gravity log, an oil density log for the well, determining, based on the oil density log, an oil-carbon density log for the well, and determining, based on the oil-carbon density log and the C/O log, a continuous oil saturation log for the well.

Abstract: A formation fluid sampling tool includes a housing, and at least one sampling probe proximate an external surface of the housing. The at least one sampling probe includes an opening sized and positioned to receive one or more heated formation fluids, and a plurality of heating elements arranged concentrically around the opening and configured to conductively heat a subterranean formation through an external surface of the sampling probe.

Abstract: The disclosure provides methods of measuring an intrinsic CO ratio in a geological formation by disposing, proximate the formation, a petrophysical tool including at least one gamma-ray detector, reading a carbon gamma-ray peak for the geological formation and an oxygen gamma-ray peak for the geological formation, determining a measured CO ratio of the geological formation from the carbon gamma-ray peak and the oxygen gamma-ray peak, and correcting the measured CO ratio by applying a corrective algorithm specific for the petrophysical tool or the type of petrophysical tool to obtain an intrinsic CO ratio of the geological formation. The corrective algorithm is derived by a mathematical analysis of measured CO ratios of a sample with a known intrinsic CO ratio using the same petrophysical tool or a petrophysical tool representative of a same type of petrophysical tool. Additional methods and systems using this method are provided.

Abstract: Provided here are compositions and improved methods for recovering portion of irreducible water saturation in a porous rock sample. Compositions used here contain a displacement fluid and a surfactant, and lead to an increased recovery of the irreducible water from the porous rock sample.

Abstract: In one possible implementation, a computer-readable tangible medium includes instructions that direct a processor to access one or more wellbore properties and a plurality of well fluid properties. Instructions are also present that direct the processor to access a distance between a proposed location of an inlet to a multiphase production logging tool and an emulsion generation location in a wellbore. Further instructions instruct the processor to predict a drop size distribution of emulsified water in the well fluid at the proposed location of the inlet to the multiphase production logging tool. Additional instructions instruct the processor to compute an estimated error in water holdup detected by the multiphase production logging tool based on the drop size distribution, and recommend deployment of a pulsed neutron logging tool in the wellbore when the estimated error in the water holdup is above a preset threshold.

Abstract: Provided here are compositions and improved methods for recovering portion of irreducible water saturation in a porous rock sample. Compositions used here contain a displacement fluid and a surfactant, and lead to an increased recovery of the irreducible water from the porous rock sample.

Abstract: Provided in some embodiments are systems and methods for monitoring cement quality of a cased well. Embodiments include conducting a cement-bond logging and a first pulsed neutron (PN) logging to generate a cement-bond log (CBL) and first pulsed neutron log (PNL) for the well, determining a first cement quality index (CQI) for the well based on the CBL and the first PNL, in response to determining that mud effects for the well have dissipated, conducting a second PN logging to generate a second PNL for the well, determining a second CQI for the well based on the CBL and the second PNL, determining a tuned CQI for the well based on the first CQI and the second CQI, conducting a follow-up PN logging to generate a follow-up PNL for the well, and determining a cement quality log for the well based on the tuned CQI and the follow-up PNL.

Abstract: In one possible implementation, a computer-readable tangible medium includes instructions that direct a processor to access one or more wellbore properties and a plurality of well fluid properties. Instructions are also present that direct the processor to access a distance between a proposed location of an inlet to a multiphase production logging tool and an emulsion generation location in a wellbore. Further instructions instruct the processor to predict a drop size distribution of emulsified water in the well fluid at the proposed location of the inlet to the multiphase production logging tool. Additional instructions instruct the processor to compute an estimated error in water holdup detected by the multiphase production logging tool based on the drop size distribution, and recommend deployment of a pulsed neutron logging tool in the wellbore when the estimated error in the water holdup is above a preset threshold.