摘要:
A method for determining formation pressure at a depth region of formations surrounding a borehole, including: keeping track of the time since cessation of drilling at the depth region; deriving formation permeability at the depth region; causing wellbore pressure to vary periodically in time and determining, at the depth region, the periodic and non-periodic component of pressure measured in the formations; determining, using the time, the periodic component and the permeability, the formation pressure diffusivity and transmissibility and an estimate of the size of the pressure build-up zone around the wellbore at the depth region; determining, using the time, the formation pressure diffusivity and transmissibility, and the non-periodic component, the leak-off rate of the mudcake at the depth region; determining, using the leak-off rate, the pressure gradient at the depth region; and extrapolating, using the pressure gradient and the size of the build-up zone, to determine the formation pressure.
摘要:
A downhole tool for extracting a sample from a subsurface formation includes an emitter of electromagnetic energy configured to heat water in the subsurface formation. A method for extracting a sample from a subsurface formation involves conveying a downhole tool in a wellbore drilled through the subsurface formation, the downhole tool having an emitter of electromagnetic energy configured to heat water in the subsurface formation, and actuating the emitter to expose a portion of the formation to electromagnetic energy.
摘要:
A downhole tool for use in a well may comprise a vessel having a piston or a valve disposed therein and defining first and second volumes wherein the first volume is configured to receive formation fluid from an inlet port, and an actuator configured to extract formation fluid, the actuator being fluidly isolated from a fluid flow path extending between the inlet port and the first volume. The downhole tool may also comprise a flow-line configured to deliver formation fluid to the vessel, and an actuator configured to register an end of the flow-line with the inlet of the vessel.
摘要:
A downhole tool for extracting a sample from a subsurface formation includes an emitter of electromagnetic energy configured to heat water in the subsurface formation. A method for extracting a sample from a subsurface formation involves conveying a downhole tool in a wellbore drilled through the subsurface formation, the downhole tool having an emitter of electromagnetic energy configured to heat water in the subsurface formation, and actuating the emitter to expose a portion of the formation to electromagnetic energy.
摘要:
A downhole tool for use in a well may comprise a vessel having a piston or a valve disposed therein and defining first and second volumes wherein the first volume is configured to receive formation fluid from an inlet port, and an actuator configured to extract formation fluid, the actuator being fluidly isolated from a fluid flow path extending between the inlet port and the first volume. The downhole tool may also comprise a flow-line configured to deliver formation fluid to the vessel, and an actuator configured to register an end of the flow-line with the inlet of the vessel.
摘要:
Cleanup monitoring and prediction in real time targeting estimation of pumpout volume versus final contamination, including detecting breakthrough of formation fluid to a sampling tool and detecting transition of cleanup regime from a predominantly circumferential cleanup regime to a predominantly vertical cleanup regime. Similar workflow can be employed for estimating contamination at the end of cleanup production for a given pumpout volume.
摘要:
Methods and apparatus to control a formation testing operation based on a mudcake leakage are disclosed. A disclosed example method for use with a downhole tool disposed in a wellbore comprises measuring a property of a mudcake layer at a first location in a wellbore, determining a value representative of an estimated leakage through the mudcake layer based on the property, and determining, based on the value, whether to continue a formation testing operation.
摘要:
A composition for use in an oil chamber of a tool includes a hydraulic oil; and a surfactant, wherein the surfactant is present at an amount sufficient to form micelles in the hydraulic oil. The composition may further include an amphiphilic copolymer. A method includes providing a hydraulic fluid composition comprising a hydraulic oil and a surfactant capable of forming micelles in the hydraulic oil; and filling a hydraulic chamber in the tool with the hydraulic fluid composition. The hydraulic fluid composition may further include an amphiphilic copolymer.
摘要:
Apparatus and methods to perform focused sampling of reservoir fluid are described. An example method couples a sampling probe to a subterranean formation and, while the sampling probe is coupled to the subterranean formation, varies a pumping ratio of at least two displacement units to reduce a contamination level of a formation flu id extracted via the sampling probe from the subterranean formation.
摘要:
Methods and apparatuses for evaluating a fluid from a subterranean formation of a wellsite via a downhole tool positionable in a wellbore penetrating a subterranean formation are provided. The apparatus relates to a downhole tool having a probe with at least two intakes for receiving fluid from the subterranean formation. The downhole tool is configured according to a wellsite set up. The method involves positioning the downhole tool in the wellbore of the wellsite, drawing fluid into the downhole tool via the at least two intakes, monitoring at least one wellsite parameter via at least one sensor of the wellsite and automatically adjusting the wellsite setup based on the wellsite parameters.