Abstract: Methods and systems are provided characterizing a formation traversed by a wellbore, wherein the formation includes at least a flushed zone and an uninvaded zone, which involve obtaining well log data based on plurality of different well log measurements of the formation at multiple depths in the wellbore. The well log data is used by a computational model that solves for a set of petrophysical parameters that characterize a portion of the formation corresponding to the multiple depths in the wellbore, wherein the set of petrophysical parameters include a cementation exponent, a saturation exponent, and a flushed zone water resistivity. The solved-for set of petrophysical parameters can be used to determine a value of water saturation of the uninvaded zone for the portion of the formation corresponding to the multiple depths in the wellbore.

Abstract: Using machine learning for sedimentary facies prediction by using one or more logs acquired in a borehole. This includes performing a petrophysical clustering of borehole depths wherein the depths of the borehole are gathered into clusters based on similarities in the one or more logs. Also performed is a log inclusion optimization, including a selection of one or more parameters of the petrophysical clustering, wherein the one or more parameters include a number and/or type of considered logs among the one or more logs and/or a clustering method. Also performed is a classification of the clusters into core depositional facies using one or more predetermined rules.

Abstract: A method for estimating all five transversely-isotropic (TI)-elastic constants using borehole sonic data obtained from at least one subterranean borehole in a transversely isotropic formation. In an embodiment, the method includes: solving for a quasi-compressional qP-wave velocity VqP using inversion algorithms based on exact solutions of the Kelvin-Christoffel equations for plane wave velocities in arbitrarily anisotropic formations, where the five TI-elastic constants may include C11, C13, C33, C55, and C66.

Abstract: A method for determining properties of a laminated formation traversed by a well or wellbore employs measured sonic data, resistivity data, and density data for an interval-of-interest within the well or wellbore. A formation model that describe properties of the laminated formation at the interval-of-interest is derived from the measured sonic data, resistivity data, and density data for the interval-of-interest. The formation model represents the laminated formation at the interval-of-interest as first and second zones of different first and second rock types. The formation model is used to derive simulated sonic data, resistivity data, and density data for the interval-of-interest. The measured sonic data, resistivity data, and density data for the interval-of-interest and the simulated sonic data, resistivity data, and density data for the interval-of-interest are used to refine the formation model and determine properties of the formation at the interval-of-interest.

Abstract: Methods and systems are provided characterizing a formation traversed by a wellbore, wherein the formation includes at least a flushed zone and an uninvaded zone, which involve obtaining well log data based on plurality of different well log measurements of the formation at multiple depths in the wellbore. The well log data is used to a computational model that solves for a set of petrophysical parameters that characterize a portion of the formation corresponding to the multiple depths in the wellbore, wherein the set of petrophysical parameters include a cementation exponent, a saturation exponent, and a flushed zone water resistivity. The solved-for set of petrophysical parameters can be used to determine a value of water saturation of the uninvaded zone for the portion of the formation corresponding to the multiple depths in the wellbore.

Abstract: A method for determining properties of a laminated formation traversed by a well or wellbore employs measured sonic data, resistivity data, and density data for an interval-of-interest within the well or wellbore. A formation model that describe properties of the laminated formation at the interval-of-interest is derived from the measured sonic data, resistivity data, and density data for the interval-of-interest. The formation model represents the laminated formation at the interval-of-interest as first and second zones of different first and second rock types. The formation model is used to derive simulated sonic data, resistivity data, and density data for the interval-of-interest. The measured sonic data, resistivity data, and density data for the interval-of-interest and the simulated sonic data, resistivity data, and density data for the interval-of-interest are used to refine the formation model and determine properties of the formation at the interval-of-interest.

Abstract: Using machine learning for sedimentary facies prediction by using one or more logs acquired in a borehole. This includes performing a petrophysical clustering of borehole depths wherein the depths of the borehole are gathered into clusters based on similarities in the one or more logs. Also performed is a log inclusion optimization, including a selection of one or more parameters of the petrophysical clustering, wherein the one or more parameters include a number and/or type of considered logs among the one or more logs and/or a clustering method. Also performed is a classification of the clusters into core depositional facies using one or more predetermined rules.

Abstract: Irreducible water saturation of fluid-storing porous reservoir rock is determined using methods that include obtaining a reservoir rock sample from the underground fluid reservoir; performing mercury saturation measurements on the reservoir rock sample for different mercury injection pressure values to obtain mercury saturation values for the different mercury injection pressure values; and estimating the irreducible water saturation (Swirr) from the mercury saturation values and the mercury injection pressure values by correcting for surface films of fluid retained on pore walls of the reservoir rock.

Abstract: A method for estimating all five transversely-isotropic (TI)-elastic constants using borehole sonic data obtained from at least one subterranean borehole in a transversely isotropic formation. In an embodiment, the method includes: solving for a quasi-compressional qP-wave velocity VqP using inversion algorithms based on exact solutions of the Kelvin-Christoffel equations for plane wave velocities in arbitrarily anisotropic formations, where the five TI-elastic constants may include C11, C13, C33, C55, and C66.

Abstract: A computer-implemented method is provided for determining properties of a formation traversed by a well or wellbore. A formation model describing formation properties at an interval-of-interest within the well or wellbore is derived from measured sonic data, resistivity data, and density data for the interval-of-interest. The formation model is used as input to a plurality of petrophysical transforms and corresponding tool response simulators that derive simulated sonic data, resistivity data, and density data for the interval-of-interest. The measured sonic data, resistivity data, and density data for the interval-of-interest and the simulated sonic data, resistivity data, and density data for the interval-of-interest are used by an inversion process to refine the formation model and determine properties of the formation at the interval-of-interest. In embodiments, properties of the formation may be radial profiles for porosity, water saturation, gas or oil saturation, or pore aspect ratio.

Abstract: A method for determining properties of a formation traversed by a well or wellbore employs measured sonic data, resistivity data, and density data for an interval-of-interest within the well or wellbore. A formation model that describe properties of the formation at the interval-of-interest is derived from the measured sonic data, resistivity data, and density data for the interval-of-interest. The formation model is used to derive simulated sonic data, resistivity data, and density data for the interval-of-interest. The measured sonic data, resistivity data, and density data for the interval-of-interest and the simulated sonic data, resistivity data, and density data for the interval-of-interest are used to refine the formation model and determine properties of the formation at the interval-of-interest.

Abstract: Methods and systems acquiring acoustic data utilizing a downhole tool conveyed within a borehole extending into a subterranean formation. The downhole tool is in communication with surface equipment disposed at a wellsite surface from which the borehole extends. Techniques involve operating at least one of the downhole tool and the surface equipment to generate a histogram based on the acoustic data, normalizing the histogram, and calculating a vug index based on the normalized histogram and based on a threshold of the normalized histogram. A vug porosity quantity may be determined based on the calculated vug index.

Abstract: Irreducible water saturation of fluid-storing porous reservoir rock is determined using methods that include obtaining a reservoir rock sample from the underground fluid reservoir; performing mercury saturation measurements on the reservoir rock sample for different mercury injection pressure values to obtain mercury saturation values for the different mercury injection pressure values; and estimating the irreducible water saturation (Swirr) from the mercury saturation values and the mercury injection pressure values by correcting for surface films of fluid retained on pore walls of the reservoir rock.

Abstract: A method for determining reservoir formation properties that consists of exciting the reservoir formation with an electromagnetic exciting field, measuring an electromagnetic signal produced by the electromagnetic exciting field in the reservoir formation, extracting from the measured electromagnetic signal a spectral complex resistivity as a function of frequency, fitting the spectral complex resistivity with an induced polarization model and deducing the reservoir formation properties from the fitting with the induced polarization model.

Abstract: A method and apparatus for processing a subterranean formation comprising stimulating and fracturing a subterranean formation, and drilling the subterranean formation wherein the drilling and fracturing occurs without removing equipment for drilling from the formation. A method and apparatus for drilling and fracturing a subterranean formation, comprising a drill string assembly and a hydraulic fracturing system, wherein the drill string and fracturing system are in communication with a wellbore and wherein the drill string and a fracture formed by the hydraulic fracturing system are less than about 1000 feet apart. A method and apparatus for processing a subterranean formation comprising fracturing a subterranean formation using a hydraulic fracturing system and drilling the subterranean formation using a drill string assembly wherein the drilling and fracturing occurs without removing the drill string from the formation, and wherein the fracturing occurs via ports in the drill string assembly.

Abstract: Methods and apparatus for the characterization of formation fluids are disclosed. A downhole tool disposed in a borehole penetrating a subterranean formation obtains a NMR measurement, effects a change in a characteristic of the formation fluid, and obtains another NMR measurement subsequent to the change. Alternatively, the downhole tool effects a radial gradient of a characteristic of the formation and obtains NMR measurements at two or more selected radial distances from the wellbore wall. A parameter representative of the subterranean formation or the formation fluid is further determined from the NMR measurements.

Abstract: Methods and devices are provided for investigating an earth formation use electro-kinetics and/or electro-osmosis measurements. In one example, the method includes creating a pressure difference in the earth formation proximate to a wellbore; measuring a generated electro-kinetic property of the earth formation proximate to the wellbore, the generated electro-kinetic property generated by the pressure difference; applying an electric field to the earth formation proximate to the wellbore; measuring a generated pressure change in the earth formation proximate to the wellbore, the generated pressure change generated by the electric field; and determining wettability of the earth formation proximate to the wellbore by the use of the measurement of the generated electro-kinetic property and the measurement of the generated pressure change.

Abstract: Methods and apparatus for the characterization of formation fluids are disclosed. A downhole tool disposed in a borehole penetrating a subterranean formation obtains a NMR measurement, effects a change in a characteristic of the formation fluid, and obtains another NMR measurement subsequent to the change. Alternatively, the downhole tool effects a radial gradient of a characteristic of the formation and obtains NMR measurements at two or more selected radial distances from the wellbore wall. A parameter representative of the subterranean formation or the formation fluid is further determined from the NMR measurements.

Abstract: A method for determining reservoir formation properties that consists of exciting the reservoir formation with an electromagnetic exciting field, measuring an electromagnetic signal produced by the electromagnetic exciting field in the reservoir formation, extracting from the measured electromagnetic signal a spectral complex resistivity as a function of frequency, fitting the spectral complex resistivity with an induced polarization model and deducing the reservoir formation properties from the fitting with the induced polarization model.

Abstract: Methods and devices are provided for investigating an earth formation use electro-kinetics and/or electro-osmosis measurements. In one example, the method includes creating a pressure difference in the earth formation proximate to a wellbore; measuring a generated electro-kinetic property of the earth formation proximate to the wellbore, the generated electro-kinetic property generated by the pressure difference; applying an electric field to the earth formation proximate to the wellbore; measuring a generated pressure change in the earth formation proximate to the wellbore, the generated pressure change generated by the electric field; and determining wettability of the earth formation proximate to the wellbore by the use of the measurement of the generated electro-kinetic property and the measurement of the generated pressure change.