Abstract: Apparatus and methods to monitor contamination levels in a formation fluid arc disclosed. An example method involves obtaining first property data indicative of a first fluid property of a formation fluid and second property data indicative of a second fluid property of the formation fluid. A correlation between the first and second property data is generated and third data is fitted to the correlation. A fitting parameter is determined based on the third data indicative of an amount of change of the first property data relative to an amount of change of the second property data.

Abstract: A downhole fluid analysis tool capable of fluid analysis during production logging that includes a phase separator and a plurality of sensors to perform analysis on the fluids collected at a subsurface location in a borehole.

Abstract: Methods and apparatus for detecting a coating on a downhole fluid sensor are disclosed. A coating may refer to a solid or liquid film on a sensor interface with the sampled fluid, caused by contaminants. Detecting a coating may be accomplished by determining a sampled fluid type and measuring at least one fluid parameter using one or more downhole fluid sensors. The coating detection further includes determining whether the measured parameters are within ranges corresponding to the determined fluid type. Additionally or alternatively, measured parameter values that remain substantially stable during sampled fluid pumping may also indicate a coated sensor.

Abstract: A method and system for characterizing asphaltene gradients of a reservoir of interest and analyzing properties of the reservoir of interest based upon such asphaltene gradients. The analysis employs a correlation that relates insoluble asphaltene concentration to spectrophotometry measurement data measured at depth.

Abstract: Methods and apparatus to characterize stock-tank oil during fluid composition analysis are disclosed. A disclosed example method to characterize a fluid associated with an underground geological formation comprises obtaining a sample of the fluid associated with the underground geological formation, determining, in a borehole associated with the underground geological formation, a stock-tank oil type for the sample of the fluid associated with the underground geological formation, and determining a property of the fluid associated with the underground geological formation based on the stock-tank oil type.

Abstract: Apparatus and methods to monitor contamination levels in a formation fluid are disclosed. An example method involves obtaining first property data indicative of a first fluid property of a formation fluid and second property data indicative of a second fluid property of the formation fluid. A correlation between the first and second property data is generated and third data is fitted to the correlation. A fitting parameter is determined based on the third data indicative of an amount of change of the first property data relative to an amount of change of the second property data.

Abstract: Apparatus and methods to analyze downhole fluids are described herein. A disclosed example method involves obtaining a sample of a downhole fluid. Additionally the example method involves ionizing at least a portion of the sample to decompose molecules having a relatively high molar mass into molecules having a relatively lower molar mass. Further, the example method involves analyzing the ionized portion of the sample to determine a parameter of the downhole fluid sample.

Abstract: Methods and apparatus for investigating a hydrocarbon bearing geological formation traversed by a borehole are disclosed. An example method to characterize a fluid associated with an underground geological formation obtains a sample of the fluid associated with the underground geological formation. The example method measures, in a borehole associated with the underground geological formation, a chemical composition and a thermophysical property of the sample of the fluid. The example method selects a mathematical model to represent the sample of the fluid based on at least one of the chemical composition or the thermophysical property and adjusts a parameter of the mathematical model based on at least one of the chemical composition or the thermophysical property to generate an adjusted mathematical model. The example method then determines a property of the fluid associated with the underground geological formation based on the adjusted mathematical model.

Abstract: A method of downhole characterization of formation fluids is provided. The method includes: estimating a rough value of the bubble point pressure of the formation fluids; depressurizing the formation fluids at a first speed to a certain pressure which is a predetermined value higher than the estimated rough value while the formation fluids are isolated in a portion of the flowline; and depressurizing the isolated fluids at a second speed which is slower than the first speed in order to measure a precise value of the bubble point pressure.

Abstract: Apparatus and methods to perform downhole fluid analysis using an artificial neural network are disclosed. A disclosed example method involves obtaining a first formation fluid property value of a formation fluid sample from a downhole fluid analysis process. The first formation fluid property value is provided to an artificial neural network, and a second formation fluid property value of the formation fluid sample is generated by means of the artificial neural network.

Abstract: A fluid analysis assembly for analyzing a fluid the fluid analysis assembly includes a chamber, a fluid movement device, a pressurization assembly and at least one sensor. The chamber defines an evaluation cavity for receiving the fluid. The fluid movement device has a force medium applying force to the fluid to cause the fluid to move within the cavity. The pressurization assembly changes the pressure of the fluid in a continuous manner. The at least one sensor communicates with the fluid for sensing at least one parameter of the fluid while the pressure of the fluid is changing in the continuous manner.

Abstract: A method for determining properties of a formation fluid is provided and includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; and considering the fluid data to calculate mass fractions of hydrocarbon flowing through the fluid analyzer. The method further includes computing gas-oil-ratio of hydrocarbon based on the mass fractions of hydrocarbon. Another method for determining a gas-oil-ratio of a formation fluid includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; considering the fluid data to derive mass fractions of gas and oil; and computing gas-oil-ratio of hydrocarbon based on the derived mass fractions.

Abstract: Methods and apparatus to characterize stock-tank oil during fluid composition analysis are disclosed. A disclosed example method to characterize a fluid associated with an underground geological formation comprises obtaining a sample of the fluid associated with the underground geological formation, determining, in a borehole associated with the underground geological formation, a stock-tank oil type for the sample of the fluid associated with the underground geological formation, and determining a property of the fluid associated with the underground geological formation based on the stock-tank oil type.

Abstract: Apparatus and methods to monitor contamination levels in a formation fluid arc disclosed. An example method involves obtaining first property data indicative of a first fluid property of a formation fluid and second property data indicative of a second fluid property of the formation fluid. A correlation between the first and second property data is generated and third data is fitted to the correlation. A fitting parameter is determined based on the third data indicative of an amount of change of the first property data relative to an amount of change of the second property data.

Abstract: A downhole fluid analysis tool capable of fluid analysis during production logging that includes a phase separator and a plurality of sensors to perform analysis on the fluids collected at a subsurface location in a borehole.

Abstract: Methods and systems are provided for downhole analysis of formation fluids by deriving fluid properties and associated uncertainty in the predicted fluid properties based on downhole data, and generating answer products of interest based on differences in the fluid properties. Measured data are used to compute levels of contamination in downhole fluids using an oil-base mud contamination monitoring (OCM) algorithm. Fluid properties are predicted for the fluids and uncertainties in predicted fluid properties are derived. A statistical framework is provided for comparing the fluids to generate, in real-time, robust answer products relating to the formation fluids and reservoirs thereof. Systematic errors in measured data are reduced or eliminated by preferred sampling procedures.

Abstract: A method for determining properties of a formation fluid is provided and includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; and considering the fluid data to calculate mass fractions of hydrocarbon flowing through the fluid analyzer. The method further includes computing gas-oil-ratio of hydrocarbon based on the mass fractions of hydrocarbon. Another method for determining a gas-oil-ratio of a formation fluid includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; considering the fluid data to derive mass fractions of gas and oil; and computing gas-oil-ratio of hydrocarbon based on the derived mass fractions.

Abstract: Methods and apparatus for investigating a hydrocarbon bearing geological formation traversed by a borehole are disclosed. An example method to characterize a fluid associated with an underground geological formation obtains a sample of the fluid associated with the underground geological formation. The example method measures, in a borehole associated with the underground geological formation, a chemical composition and a thermophysical property of the sample of the fluid. The example method selects a mathematical model to represent the sample of the fluid based on at least one of the chemical composition or the thermophysical property and adjusts a parameter of the mathematical model based on at least one of the chemical composition or the thermophysical property to generate an adjusted mathematical model. The example method then determines a property of the fluid associated with the underground geological formation based on the adjusted mathematical model.

Abstract: A method of assuring the collection of reliable and quality fluid sample includes the steps of acquiring a fluid sample at a point of acquisition, analyzing physical and chemical properties of the fluid sample at the point of acquisition; recording the point of acquisition sample properties in an electronic database archive, analyzing physical and chemical properties of the fluid sample at a location remote from the point of acquisition, recording the remote location sample properties in the archive, validating the fluid sample through comparison of the point of acquisition sample properties and the remote location sample properties and recording the validated sample properties in the archive.

Abstract: A fluid analysis assembly for analyzing a fluid the fluid analysis assembly includes a chamber, a fluid movement device, a pressurization assembly and at least one sensor. The chamber defines an evaluation cavity for receiving the fluid. The fluid movement device has a force medium applying force to the fluid to cause the fluid to move within the cavity. The pressurization assembly changes the pressure of the fluid in a continuous manner. The at least one sensor communicates with the fluid for sensing at least one parameter of the fluid while the pressure of the fluid is changing in the continuous manner.