Abstract: Systems and methods of the present disclosure include a fluid sampling system that includes a fluid sampling tool and a controller. The fluid sampling tool includes a probe configured to draw a fluid from a formation within which the fluid sampling tool is disposed during an oil and gas well operation. The fluid sampling tool also includes a spectrometer configured to detect raw data relating to optical properties of the fluid. The raw data relating to the optical properties of the fluid includes optical absorbance at a plurality of wavelengths.

Abstract: Systems and methods of the present disclosure include a fluid sampling system that includes a fluid sampling tool and a controller. The fluid sampling tool includes a probe configured to draw a fluid from a formation within which the fluid sampling tool is disposed during an oil and gas well operation. The fluid sampling tool also includes a spectrometer configured to detect raw data relating to optical properties of the fluid. The raw data relating to the optical properties of the fluid includes optical absorbance at a plurality of wavelengths.

Abstract: NMR-based lithium measuring and monitoring downhole tools and methods measure at least one lithium concentration of a fluid in a borehole and/or a surrounding formation of the borehole, wherein the downhole tool has an NMR sensor having a magnet-coil geometry with at least one magnet and a RF coil tuned to match a Larmor frequency of a nucleus of lithium. The downhole tools and methods acquire an NMR-based lithium concentration measurement of a fluid at a sensitive region within the wellbore and/or formation that is defined by the magnet-coil geometry of the NMR sensor and determine a lithium concentration of the fluid at the sensitive region based on the acquired NMR-based lithium concentration measurement.

Abstract: NMR-based lithium measuring and monitoring downhole tools and methods measure at least one lithium concentration of a fluid in a borehole and/or a surrounding formation of the borehole, wherein the downhole tool has an NMR sensor having a magnet-coil geometry with at least one magnet and a RF coil tuned to match a Larmor frequency of a nucleus of lithium. The downhole tools and methods acquire an NMR-based lithium concentration measurement of a fluid at a sensitive region within the wellbore and/or formation that is defined by the magnet-coil geometry of the NMR sensor and determine a lithium concentration of the fluid at the sensitive region based on the acquired NMR-based lithium concentration measurement.

Abstract: In some examples, an optical density of a contaminant in a fluid sample is computed. An optical density of a target fluid in the fluid sample is computed using optical densities of the fluid sample at a plurality of wavelengths. Based on the computed optical density of the contaminant and the computed optical density of the target fluid, a level of contamination by the contaminant in the fluid sample is determined.

Abstract: A technique facilitates detection and analysis of constituents, e.g. chemicals, which may be found in formation fluids and/or other types of fluids. The technique comprises intermittently introducing a first fluid and a second fluid into a channel in a manner which forms slugs of the first fluid separated by the second fluid. The intermittent fluids are flowed through the channel to create a mixing action which mixes the fluid in the slugs. The mixing increases the exchange, e.g. transfer, of the chemical constituent between the second fluid and the first fluid. The exchange aids in sensing an amount of the chemical or chemicals for analysis. In many applications, the intermittent introduction, mixing, and measuring can be performed in a subterranean environment.

Abstract: A method and system for detecting mercury in a hydrocarbon-containing fluid stores a sample of the hydrocarbon-containing fluid in a first reservoir. A liquid phase reagent solution is stored in a second reservoir. The liquid phase reagent solution includes nanoparticles with an affinity to mercury, wherein the nanoparticles are suspended as a colloid in the liquid phase reagent solution. The sample of the hydrocarbon-containing fluid is delivered from the first reservoir into a first port of a fluidic device while the liquid phase reagent solution is delivered from the second reservoir into a second port of the fluidic device such that the fluidic device produces slug flow. The slug flow is subject to optical analysis that determines concentration of mercury in the sample of the hydrocarbon-containing fluid.

Abstract: Methods may include emplacing a wellbore tool in a wellbore, the wellbore tool including a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr, measuring a sample from the wellbore using the wellbore tool, and determining a molecular weight of one or more components of the sample from the measured response of the wellbore tool. Methods may also include establishing a library of one or more chemical components, emplacing a wellbore tool in a wellbore, the wellbore tool including a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr, measuring a sample from the wellbore using the wellbore tool, comparing the measured response from the wellbore tool for the sample with results from the library of one or more chemical components, and determining a molecular weight of one or more components of the sample.

Abstract: A technique facilitates detection and analysis of constituents, e.g. chemicals, which may be found in formation fluids and/or other types of fluids. The technique comprises intermittently introducing a first fluid and a second fluid into a channel in a manner which forms slugs of the first fluid separated by the second fluid. The intermittent fluids are flowed through the channel to create a mixing action which mixes the fluid in the slugs. The mixing increases the exchange, e.g. transfer, of the chemical constituent between the second fluid and the first fluid. The exchange aids in sensing an amount of the chemical or chemicals for analysis. In many applications, the intermittent introduction, mixing, and measuring can be performed in a subterranean environment.

Abstract: A technique facilitates detection and analysis of constituents, e.g. chemicals, which may be found in formation fluids and/or other types of fluids. The technique comprises intermittently introducing a first fluid and a second fluid into a channel in a manner which forms slugs of the first fluid separated by the second fluid. The intermittent fluids are flowed through the channel to create a mixing action which mixes the fluid in the slugs. The mixing increases the exchange, e.g. transfer, of the chemical constituent between the second fluid and the first fluid. The exchange aids in sensing an amount of the chemical or chemicals for analysis. In many applications, the intermittent introduction, mixing, and measuring can be performed in a subterranean environment.

Abstract: Methods are provided for reservoir analysis. In some embodiments, a reservoir may be analyzed by obtaining abundance ratios at a first measurement station and a second measurement station and determining an abundance ratio trend. Abundance ratios at a third measurement station may be obtained and plotted versus depth with the previously obtained abundance ratios. A change in the abundance ratio trend may be identified and result in further investigation of the reservoir. If the abundance ratio is unchanged, additional abundance ratios may be obtained and plotted versus depth to further evaluate the abundance ratio trend. Methods for reservoir analysis using fluid predictions with and without offset well information are also provided.

Abstract: Methods may include emplacing a wellbore tool in a wellbore, the wellbore tool including a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr, measuring a sample from the wellbore using the wellbore tool, and determining a molecular weight of one or more components of the sample from the measured response of the wellbore tool. Methods may also include establishing a library of one or more chemical components, emplacing a wellbore tool in a wellbore, the wellbore tool including a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr, measuring a sample from the wellbore using the wellbore tool, comparing the measured response from the wellbore tool for the sample with results from the library of one or more chemical components, and determining a molecular weight of one or more components of the sample.

Abstract: Wellbore tools in accordance with the present disclosure may include a gas chromatograph; and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr. Systems in accordance with the present disclosure may include a gas chromatograph; and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr. Methods in accordance with the present disclosure may include emplacing a wellbore tool in a wellbore, the wellbore tool containing a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr; drawing a sample of a fluid from the wellbore into the wellbore tool; and determining a molecular weight of one or more components of the fluid.

Abstract: Wellbore tools in accordance with the present disclosure may include a gas chromatograph; and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr. Systems in accordance with the present disclosure may include a gas chromatograph; and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr. Methods in accordance with the present disclosure may include emplacing a wellbore tool in a wellbore, the wellbore tool containing a gas chromatograph and a mass spectrometer, wherein the mass spectrometer is configured to operate at a pressure greater than 10?2 Torr; drawing a sample of a fluid from the wellbore into the wellbore tool; and determining a molecular weight of one or more components of the fluid.

Abstract: A method for determining scaling cation concentration may include introducing a first solution that includes a scaling cation, incrementally adding a portion of the first solution to a volume of a second solution comprising a counter scaling anion and a complexing agent, wherein the second solution comprises a fixed concentration of the counter scaling anion and the agent, to form a mixed solution, adding the first solution to the second solution until a precipitate of the scaling cation and the counter scaling anion forms, and determining the scaling cation concentration of the first solution.

Abstract: In some examples, an optical density of a contaminant in a fluid sample is computed. An optical density of a target fluid in the fluid sample is computed using optical densities of the fluid sample at a plurality of wavelengths. Based on the computed optical density of the contaminant and the computed optical density of the target fluid, a level of contamination by the contaminant in the fluid sample is determined.

Abstract: Methods are provided for reservoir analysis. In some embodiments, a reservoir may be analyzed by obtaining abundance ratios at a first measurement station and a second measurement station and determining an abundance ratio trend. Abundance ratios at a third measurement station may be obtained and plotted versus depth with the previously obtained abundance ratios. A change in the abundance ratio trend may be identified and result in further investigation of the reservoir. If the abundance ratio is unchanged, additional abundance ratios may be obtained and plotted versus depth to further evaluate the abundance ratio trend. Methods for reservoir analysis using fluid predictions with and without offset well information are also provided.

Abstract: Methods are provided for reservoir analysis. In some embodiments, a reservoir may be analyzed by obtaining abundance ratios at a first measurement station and a second measurement station and determining an abundance ratio trend. Abundance ratios at a third measurement station may be obtained and plotted versus depth with the previously obtained abundance ratios. A change in the abundance ratio trend may be identified and result in further investigation of the reservoir. If the abundance ratio is unchanged, additional abundance ratios may be obtained and plotted versus depth to further evaluate the abundance ratio trend. Methods for reservoir analysis using fluid predictions with and without offset well information are also provided.

Abstract: A method of analyzing physical properties of a sample includes obtaining the sample and obtaining an electromagnetic spectrum of the sample using terahertz spectroscopy. A sample complex permittivity is computed from the electromagnetic spectrum of the sample. The method further includes estimating the constituents and the constituent fractions and computing an estimated effective complex permittivity based upon a model and the constituent fractions. The method further includes comparing the computed sample complex permittivity with the estimated effective complex permittivity in order to determine the physical properties the sample.

Abstract: Methods and devices for determining a plus fraction of a plus fraction of a gas chromatogram are provided. A gas chromatogram may obtained, such as from a downhole gas chromatograph module of a fluid analysis tool. The plus fraction of the gas chromatogram may be determined using one or more of a ratiometric determination, fitting an exponential decay function, and fitting a probability density gamma function.