Methods, systems, devices, and products for estimating at least one parameter of interest of a volume of interest of an earth formation using nuclear radiation based measurements. Logging tools include a limited aperture collimated radiation beam source, detectors, and at least one processor configured to take measurements. The source is configured to emit a beam of radiation radially from the logging tool into an elongated volume of interest outside the wellbore such that the beam penetrates a plurality of zones of the volume of interest. Each zone represents a range of radial depths corresponding to a respective infrastructure component associated with the wellbore, such as nested tubulars. Each detector has a unique angle of detection and is configured to generate measurement information in response to spatially coherent backscattered gamma rays. Each detector is associated with scattering events at one of the plurality of zones.

A measurement compensation mechanism for an electronic radiation source-based borehole logging tool that compensates for geometric variations in the direction output of an x-ray source is provided, the measurement compensation system including: at least one electronic radiation source; at least one radiation shield; at least three reference detectors; and at least one borehole measuring radiation detector. A method of compensating the measurement of an electronic radiation source-based borehole logging tool that compensates for geometric variations in the direction output of an x-ray source is also provided, the method including at least: measuring an azimuthal distribution of radiation intensities equidistant from an electronic radiation source in order to correct a measured radiation value of a borehole-measuring radiation detector relative to the borehole-measuring radiation detector's azimuthal measurement direction.

Systems and methods include a computer-implemented method for creating artificial real-time gamma ray (GR) images for well placement. Real-time azimuthal density data is determined from drilling of a well. An azimuthal density data set is generated using the real-time azimuthal density data. The azimuthal density data set is generated with a greater sampling rate than a real-time sampling rate of the real-time azimuthal density data. An azimuthal density curve depth match is performed using the azimuthal density data set. Performing the azimuthal density curve depth match includes creating a depth shift match table. A high-resolution sector near-bit gamma ray (GR) image is generated using the azimuthal density curve depth match and the depth shift match table. The high-resolution sector near-bit GR image is oriented to a top of a wellbore for the well.

A subsurface continuous radioisotope environmental monitor that provides a continuous monitoring of the possible presence of radioactive species in subsurface groundwater. The detector and all supporting system elements are specifically constructed and equipped to be permanently mounted in a well or borehole to continuously detect and record radiation decay of radioactive species that are borne by subsurface water flow to that sampling area. The system operates by placing a detection element in a housing such that subsurface water that reaches the bore or well can flow in contact with the detection element. The system can employ several detection modes and materials. The detector includes SiPMs operating in a coincidence spectroscopy configuration to significantly reduce spurious signals due to thermal noise as well as increasing the total amount of signals collected.

Methods of elemental imaging of a formation include acquiring spectral gamma ray measurement, acquiring a total gamma ray image, deriving structure information of the formation from the total gamma ray image, and applying the structure information to the spectral gamma ray measurement to form an elemental image. In the present methods, the structure information of the formation is derived from comparing the total gamma ray logs for each azimuthal sector to a derived total gamma ray log. The derived total gamma ray log is acquired from the total gamma ray image by summing over all azimuth bins or the spectral gamma ray measurement by summing over all energy bins.

A single crystal yttrium aluminum perovskite scintillator has a minimum thickness of at least 5 mm and a transmittance of at least 50% at a wavelength of 370 nm. A method for fabricating the yttrium aluminum perovskite scintillator includes acquiring a yttrium aluminum perovskite single crystal boule, annealing the yttrium aluminum perovskite single crystal boule in an oxygen containing environment to obtain a partially annealed crystal, and annealing the partially annealed crystal in an inert environment or a reducing environment to obtain the yttrium aluminum perovskite single crystal scintillator.

In one example, a system and method for correlating first well log data with a previously generated well with second well log data from an actively drilling well. A identifying a starting depth is identified above a geological formation. The first well log data is dynamically gain adjusted to the second well log data. The gain adjusted first well log data is dynamically depth warped to the second well log data to correlate the first well log data with the second well log data.

Various apparatus or methods are arranged to operate a tool downhole in a well, where the tool has a detection package operable to detect gamma rays. Deviation of energy spectra of detected gamma rays in each selected energy window of a set of selected energy windows with respect to reference energy spectra of the respective selected energy window can be detected. One or more properties of one or more regions around the tool can be determined from the deviations, the regions being between the tool and a source of the detected gamma rays in a formation around the well. Additional apparatus, systems, and methods having a gamma ray detection package can operate in a variety of applications.

A method and system for environmental monitoring of logging-while-drilling (LWD) components. In one embodiment the system includes a formation sensor configured to generate a signal related to a property of a surrounding rock formation, and a first environmental sensor fastened to the formation sensor and configured to generate a signal related to a first environmental condition experienced by the first environmental sensor. The formation sensor and first environmental sensor may be contained in a package of an LWD tool.

The present disclosure relates to an apparatus and a method for analysis of geophysical logging data obtained by using gamma ray logging, so as to predict lithofacies of strata by analysis of geophysical logging data, for lithofacies across a wide area, on the basis of data analyzed using gamma ray logging. The present disclosure comprises: a gamma ray emission unit; a gamma ray transmission and reception unit; and a logging determination unit. Thus, the present disclosure can analyze geophysical logging data, for lithofacies across a wide area, on the basis of data analyzed obtained by using gamma ray logging, by clustering and patterning the results of the geophysical logging data only for significant strata, and can analyze strata with greater accuracy.