Halliburton Energy Services, Inc.

Weatherford Technology Holdings, LLC

Landmark Graphics Corporation

Natasa Mekic

John Andrew Quirein

Mehdi Eftekhari Far

Gregory J Schmid

Weijun Guo

Junsheng Hou

Daniel Francois Dorffer

Richard R Pemper

Matthew McCleskey

Christopher S McIlroy

Richard Pemper

Methods and systems for determining formation salinity using pulsed neutron (PN) tools are described. Embodiments of the described methods involve binning chlorine yields or chlorine count rates arising from capture events into early and late capture regimes, which may be used to attribute the events to either the borehole or the formation.

Determination of formation water salinity using time resolved chlorine capture gamma spectroscopy

Methods and systems for determining bulk density and/or neutron porosity of a formation are described herein. The methods and systems use a pulsed neutron (PN) tool and may be performed with a tool having a single gamma detector though tools with multiple detectors may be used as well. The PN tool may be a geochemical logging tool. The methods and systems involve partitioning the time spectrum into pluralities of bins that are indicative of non-clay mineral elements and of shale/clay to the overall bulk density.

Determination of neutron porosity and bulk density from a pulsed neutron tool

Methods, tools, and systems for determining the lithium concentration of a formation traversed by a wellbore using pulsed neutron logging are described. Since determining lithium directly using pulsed neutron logging is problematic, this disclosure provides ways of determining lithium concentration indirectly using models that relate lithium concentration with concentrations of other elements that are predicted to be associated with lithium.

Pulsed neutron logging for petrolithium

Methods and tools for determining one or more parameters of an earth formation using time-of-flight (TOF) measurements of fast neutrons through the formation are disclosed. The disclosed tools feature a neutron source capable of emitting a population of fast neutrons having a distribution of neutron energies and one or more neutron detectors. The TOF of the fast neutrons travelling from the neutron source to the detector(s) and traversing a portion of the formation is measured and binned as a function of TOF (which is a function of neutron energy). By determining which neutron energies are attenuated by the intervening formation, the composition of the intervening formation is determined.

Neutron time of flight wellbore logging

Example embodiments are described for a method and system for logging data processing in determining permeability anisotropy effects. A permeability anisotropy model is used to derive a relationship between formation permeability anisotropy and resistivity anisotropy in both TI and BA formations. Implementations can provide the permeability anisotropy plus the true reservoir (or sand) permeability by using an integrated interpretation of the MCI resistivity anisotropy measurements with conventional permeability logs from other sensors (e.g., NMR or sonic). Biaxial and triaxial permeability components of the permeability anisotropy tensor can be determined for application to synthetic and field log interpretations.

Permeability anisotropy assessment in subsurface anisotropic formations

In accordance with embodiments of the present disclosure, a simplified geomechanical model that considers the anisotropic (e.g., directional) properties of a formation and the presence of natural fractures in the formation is provided. A system and method may be designed according to the present disclosure to create a simplified geomechanical model of a horizontally laminated formation that includes pre-existing natural fractures. The simplified geomechanical model can be used to calculate the fracture closure pressure of the formation and to design a fracturing operation for injecting fracture fluid into the formation, thus improving the efficiency of a subterranean operation. The disclosed model may provide a more realistic model for fractured shales than an isotropic or vertically transverse isotropic (VTI) model. In addition, the disclosed model may be simpler to implement than a full orthorhombic model.

Simplified geomechanical model of stresses on an orthorhombic media

Disclosed herein are embodiments of systems, methods, and computer program products for determining fracture and stress characterization using layer thickness variation over an azimuthally anisotropic medium, which may include one or more of the following functions: acquiring seismic data by recording reflected seismic waves in at least two directions; sorting of the seismic data so that offset is zero at a center and increases radially from a single common-point (CMP) gather for a plurality of data points; generating a multi-dimensional volume by juxtaposing a set of common-offset sections by one of their common-depth point (CDP) and CMP locations; selecting reflectors for each layer in the one of the multi-dimensional volume; computing layer parameters including effective anisotropy and interval anisotropy for each layer in the multi-dimensional volume based on a geometry of the reflectors selected for each layer in the multi-dimensional volume; and applying the layer parameters to an earth model.

Fracture and stress characterization using layer thickness variation

In some embodiments, a method and apparatus, as well as an article, may operate to estimate a property of an earth formation by generating at least one shale model to represent an earth formation comprised of a non-zero percentage of shale. The shale model includes two curves to represent a relationship between a porosity parameter and a pulsed neutron measurement at two different corresponding percentages of gas saturation, respectively. A matrix model representing an earth formation with 0% shale is combined with one or more shale models to create a formation model. Measured pulsed neutron data is compared with the formation model to estimate a property of the earth formation. Additional apparatus, systems, and methods are disclosed.

Method to correct and pulsed neutron fan based interpretation for shale effects

Systems and methods for simultaneously correcting the effects of deviation and dispersion on sonic log measurements of deviated wells in laminated formations and validating the corrected sonic log measurements using rock physics cross-plots.

Correcting the effects of deviation and dispersion on sonic log measurements of deviated wells in laminated formations

Systems and methods for identifying formation layer boundaries on well log measurements using a second derivative of the last iteratively smoothed well log measurements and a fluctuation index to determine the extent of smoothing.

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Spring, TX, United States of America

Natasa Mekic