摘要:
System and/or methods for removing noise from measurement data are disclosed. For example, pressure measurements may be used to identify a flow regime using the derivative of each of the pressure measurements. A time window may be defined about each pressure measurement and numerous or even all pressure measurements within the time window may be used to calculate the pressure derivative of each pressure measurement. A least-squares method or a least-absolute-deviations method may be used to compute a pressure-derivative curve. The iteratively-reweighted least-squares method may be used to solve least-absolute-deviation problems to compute a pressure-derivative curve with enhanced smoothing.
摘要:
A method of sampling fluid from a subterranean formation includes positioning a first tool having a heater in a borehole so that the heater is adjacent a portion of the subterranean formation; heating with the heater the portion of the subterranean formation; removing the first tool from the borehole; orienting a second tool having a sampling probe in the borehole so that the sampling probe is to contact a portion of the subterranean formation heated by the heater; and obtaining via the sampling probe a fluid sample from the portion of the subterranean formation heated by the heater.
摘要:
Example methods and apparatus to determine phase-change pressures are disclosed. A disclosed example method includes capturing a fluid in a chamber, pressurizing the fluid at a plurality of pressures, measuring a plurality of transmittances of a signal through the fluid at respective ones of the plurality of pressures, computing a first magnitude of a first subset of the plurality of transmittances, computing a second magnitude of a second subset of the plurality of transmittances, comparing the first and second magnitudes to determine a phase-change pressure for the fluid.
摘要:
Samples of hydrocarbon are obtained with a coring tool. An analysis of some thermal or electrical properties of the core samples may be performed downhole. The core samples may also be preserved in containers sealed and/or refrigerated prior to being brought uphole for analysis. The hydrocarbon trapped in the pore space of the core samples may be extracted from the core samples downhole. The extracted hydrocarbon may be preserved in chambers and/or analyzed downhole.
摘要:
A method of sampling fluid from a subterranean formation includes positioning a first tool having a heater in a borehole so that the heater is adjacent a portion of the subterranean formation: heating with the heater the portion of the subterranean formation; removing the first tool from the borehole; orienting a second tool having a sampling probe in the borehole so that the sampling probe is to contact a portion of the subterranean formation heater by the heater; and obtaining via the sampling probe a fluid sample from the portion of the subterranean formation heater by the heater.
摘要:
Apparatus and methods to remove impurities at a sensor in a downhole tool are disclosed. During the testing and/or sampling of formation fluid in a borehole, the downhole tool creates a transient high rate of fluid flow of the formation fluid to remove impurities at the sensor.
摘要:
A method of retrieving a formation fluid from a formation adjacent a borehole wall includes estimating at least one of a permeability of the formation and a viscosity of the formation fluid. A first tool is selected based on the estimation, the first tool being selected from one of a heating and sampling tool, an injection and sampling tool, and a coring tool. An attempt to retrieve a formation fluid sample from the formation is then made with the first tool, and a formation fluid sample is retrieved from the formation. A second retrieval process may then be initiated, in which the second retrieval process includes increasing the mobility of the formation fluid.
摘要:
A method for refining fluid sample data includes obtaining optical density data for a fluid sample in at least two color channels and at least one fluid component channel and determining a color-absorption function from the optical density data for the fluid sample in the at least two color channels. The method also includes calculating a portion of the optical density caused by color absorptions in each of the at least one fluid component channels, and de-coloring the optical density data in each of the at least one fluid component channels by removing the portion of the optical density data caused by color absorption.
摘要:
Samples of hydrocarbon are obtained with a coring tool. An analysis of some thermal or electrical properties of the core samples may be performed downhole. The core samples may also be preserved in containers sealed and/or refrigerated prior to being brought uphole for analysis. The hydrocarbon trapped in the pore space of the core samples may be extracted from the core samples downhole. The extracted hydrocarbon may be preserved in chambers and/or analyzed downhole.
摘要:
A method for determining permeability of a reservoir using a packer-probe formation testing tool. The elements of the method include generating, using a dual packer tool module, fluid flows from the reservoir into a wellbore, obtaining pressure data associated with the fluid flows using an observation probe tool module, wherein the packer-probe formation testing tool comprises the dual packer module and the observation probe tool module, identifying a portion of the pressure data corresponding to a spherical flow regime, determining horizontal permeability based on the portion of the pressure data, and displaying an output generated using the horizontal permeability.