Abstract: Methods for logging a well utilizing natural radioactivity originating from clay based particulates are disclosed. The methods can include utilizing a gravel pack slurry containing a liquid and gravel pack particles to hydraulically place the particles into a gravel pack zone of a borehole penetrating a subterranean formation and obtaining a post gravel pack data set by lowering into the borehole traversing the subterranean formation a gamma ray detector and detecting gamma rays resulting from a native radioactivity of the gravel pack particles. The methods can further include using the post gravel pack data set to determine a location of the gravel pack particles and correlating the location of the gravel-pack particles to a depth measurement of the borehole to determine the location, height, and/or percent fill of gravel-pack particles placed in the gravel pack zone of the borehole.

Abstract: Methods for logging a well utilizing natural radioactivity originating from clay based particulates are disclosed. The methods can include utilizing a gravel pack slurry containing a liquid and gravel pack particles to hydraulically place the particles into a gravel pack zone of a borehole penetrating a subterranean formation and obtaining a post gravel pack data set by lowering into the borehole traversing the subterranean formation a gamma ray detector and detecting gamma rays resulting from a native radioactivity of the gravel pack particles. The methods can further include using the post gravel pack data set to determine a location of the gravel pack particles and correlating the location of the gravel-pack particles to a depth measurement of the borehole to determine the location, height, and/or percent fill of gravel-pack particles placed in the gravel pack zone of the borehole.

Abstract: A method for evaluating induced fractures in a wellbore includes obtaining a first set of data in a wellbore using a downhole logging tool. A first proppant is pumped into the wellbore, after the first set of data is captured. The first proppant includes a first tracer that is not radioactive. A second proppant is also pumped into the wellbore, after the first proppant is pumped into the wellbore. The second proppant includes a second tracer that is not radioactive, and the second tracer is different than the first tracer. A second set of data is obtained in the wellbore using the downhole tool after the first and second proppants are pumped into the wellbore. The first and second sets of data are compared.

Abstract: Methods for logging a well utilizing natural radioactivity originating from clay based particulates are disclosed. The methods can include utilizing a gravel pack slurry containing a liquid and gravel pack particles to hydraulically place the particles into a gravel pack zone of a borehole penetrating a subterranean formation and obtaining a post gravel pack data set by lowering into the borehole traversing the subterranean formation a gamma ray detector and detecting gamma rays resulting from a native radioactivity of the gravel pack particles. The methods can further include using the post gravel pack data set to determine a location of the gravel pack particles and correlating the location of the gravel-pack particles to a depth measurement of the borehole to determine the location, height, and/or percent fill of gravel-pack particles placed in the gravel pack zone of the borehole.

Abstract: A method of estimating formation porosity using a neural network for neutron porosity tools. In the training stage, the near-to-far ratio, environmental variables, such as mineralogy, borehole size, standoff etc., are fed to the inputs and the neural network is trained for obtaining the related true porosity (the output). The trained neural network is implanted into tool's firmware for the real time porosity measurement, accounting for the environmental effects considered during training.

Abstract: A downhole instrument for estimating density of sub-surface materials includes: a neutron source, a source monitoring detector, a near detector and a far detector. Each of the detectors may be coupled to an electronics unit adapted for receiving a detection signal from each of the detectors and compensating the detection signal for at least one of the near detector and the far detector according to the detection signal of the source monitoring detector. A method for estimating density is provided.

Abstract: An apparatus for measuring radiation in a borehole penetrating the Earth, the apparatus includes: a downhole tool having a structure defining a cavity; and one or more radiation detection components integrated into the cavity and configured to measure the radiation. An apparatus conveyable through a borehole for measuring radiation downhole and a method of producing a downhole apparatus for measuring radiation are provided.

Abstract: An apparatus for estimating a property of an earth formation penetrated by a borehole, the apparatus includes: a carrier configured to be conveyed through the borehole; a neutron source disposed at the carrier and configured to irradiate the earth formation with neutrons; a neutron detector disposed at the carrier and configured to detect neutrons reflected by the earth formation to the detector; a neutron reflector disposed partially around the detector, an area of the detector not covered by the reflector being configured to admit the reflected neutrons; and a neutron absorber disposed at least around the reflector.

Abstract: A method of estimating formation porosity using a neural network for neutron porosity tools. In the training stage, the near-to-far ratio, environmental variables, such as mineralogy, borehole size, standoff etc., are fed to the inputs and the neural network is trained for obtaining the related true porosity (the output).

Abstract: An apparatus for measuring radiation in a borehole penetrating the Earth, the apparatus includes: a downhole tool having a structure defining a cavity; and one or more radiation detection components integrated into the cavity and configured to measure the radiation. An apparatus conveyable through a borehole for measuring radiation downhole and a method of producing a downhole apparatus for measuring radiation are provided.

Abstract: A downhole instrument for estimating density of sub-surface materials includes: a neutron source, a source monitoring detector, a near detector and a far detector. Each of the detectors may be coupled to an electronics unit adapted for receiving a detection signal from each of the detectors and compensating the detection signal for at least one of the near detector and the far detector according to the detection signal of the source monitoring detector. A method for estimating density is provided.

Abstract: An apparatus for estimating a property of an earth formation penetrated by a borehole, the apparatus includes: a carrier configured to be conveyed through the borehole; a neutron source disposed at the carrier and configured to irradiate the earth formation with neutrons; a neutron detector disposed at the carrier and configured to detect neutrons reflected by the earth formation to the detector; a neutron reflector disposed partially around the detector, an area of the detector not covered by the reflector being configured to admit the reflected neutrons; and a neutron absorber disposed at least around the reflector.