Abstract: A method and system for azimuth measurements using one or more gyro sensors is disclosed. The method includes acquiring a first data from each of the gyro sensors with an input axis aligned to a first angular orientation and acquiring a second data from each of the gyro sensors with the input axis flipped to a second angular orientation opposite to the first angular orientation. An earth rate component at the first angular orientations is determined based on a difference between the first data and the second data to cancel out bias of each of the gyro sensors. The method may include acquiring a third data of the gyro sensor with the input axis aligned to the same angular orientation as the first angular orientation. An average of the first data and the third data may be used instead of the first data for determining the earth rate component.

Abstract: A downhole tool, configured to be suspended in a borehole traversing an earth formation, includes a downhole data acquisition system placed in the tool body and electrically connected to an electric power generator at the formation surface. The downhole data acquisition system includes a sensor for detecting local conditions in the borehole, and a transducer for transducing the voltage of an input signal from high to low or low to high. The transducer having a gallium nitride or silicon carbide based discrete semiconductor device.

Abstract: An apparatus for azimuth measurements is provided. The apparatus comprises a housing and a plurality of gyro sensors aligned in the housing. Each of the plurality of gyro sensors has an input axis for angular velocity measurements. There is provided a drive unit for rotating each of the plurality of gyro sensors about a rotation axis. Each of the plurality of gyro sensors changes orientation of the input axis with the drive unit.

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: Example methods and apparatus to detect phase separation in downhole fluid sampling operations are disclosed. An example method to detect a phase separation condition of a fluid from a subterranean involves obtaining a sample of the fluid, measuring a first characteristic value of the sample, measuring a second characteristic value of the sample and comparing the first characteristic value to a first reference value associated with a single-phase condition of the fluid to generate a corresponding first comparison result. The example method then compares the second characteristic value to a second reference value associated with the single-phase condition of the fluid to generate a corresponding second comparison result and detects the phase separation condition of the fluid based on the first and second comparison results.

Abstract: Example microfluidic methods and apparatus to perform in situ chemical detection are disclosed. A disclosed example downhole apparatus comprises a microfluidic chamber to introduce a microfluidic-scale drop of a reagent into a formation fluid to form a mixed fluid, a flowline to fluidly couple the formation fluid from a geologic formation to the microfluidic chamber, and a detector to measure a property of the mixed fluid, the property representative of a presence of a chemical in the formation fluid.

Abstract: Subterranean oilfield high-temperature devices configured or designed to facilitate downhole monitoring and high data transmission rates with laser diodes that are configured for operation downhole, within a borehole, at temperatures in excess of 115 degrees centigrade without active cooling.

Abstract: An apparatus for azimuth measurements comprises an elongated housing, a plurality of gyro sensors, each of the gyro sensors having an input axis for angular velocity measurements, spherical sensor holders arranged along the longitudinal direction of the housing, at least one motor for driving the sensor holders, a transmission mechanism for transmitting a rotation force from the motor to each of the sensor holders and a controller for controlling a rotation of the motor. Each of the sensor holders has one of the gyro sensors and is rotatable about a rotation axis so as to change the orientation of the input axis of the gyro sensor.

Abstract: A sonde and an apparatus for the deployment thereof against a well casing is described, the sonde comprising a resilient C-shaped member and at least one sensor.

Abstract: Subterranean oilfield sensor systems and methods are provided. The subterranean oilfield sensor systems and methods facilitate downhole monitoring and high data transmission rates with power provided to at least one downhole device by a light source at the surface. In one embodiment, a system includes uphole light source, a downhole sensor, a photonic power converter at the downhole sensor, an optical fiber extending between the uphole light source and the photonic power converter, and downhole sensor electronics powered by the photonic power converter. The photonic power converter is contained in a high temperature resistant package. For example, the high temperature resistant package and photonic power converter may operate at temperatures of greater than approximately 100° C.

Abstract: An apparatus for azimuth measurements comprises an elongated housing, a plurality of gyro sensors, each of the gyro sensors having an input axis for angular velocity measurements, spherical sensor holders arranged along the longitudinal direction of the housing, at least one motor for driving the sensor holders, a transmission mechanism for transmitting a rotation force from the motor to each of the sensor holders and a controller for controlling a rotation of the motor. Each of the sensor holders has one of the gyro sensors and is rotatable about a rotation axis so as to change the orientation of the input axis of the gyro sensor.

Abstract: Some principles described herein contemplate implementation of downhole imaging for the characterization of formation fluid samples in situ, as well as during flow through production tubing, including subsea flow lines, for short term investigation, permanent, and/or long term installations. Various methods and apparatus described herein may facilitate downhole testing. For example, some embodiments facilitate multi-dimensional fluorescence spectrum measurement testing downhole and correlating the fluorescence with other oil properties.

Abstract: Some principles described herein contemplate implementation of downhole imaging for the characterization of formation fluid samples in situ, as well as during flow through production tubing, including subsea flow lines, for short term investigation, permanent, and/or long term installations. Various methods and apparatus described herein may facilitate downhole testing. For example, some embodiments facilitate multi-dimensional fluorescence spectrum measurement testing downhole.

Abstract: Subsea apparatus and a method for sampling and analysing fluid from a subsea fluid flowline proximate a subsea well is provided, wherein the apparatus comprises at least one housing located in close proximity to said subsea fluid flowline; at least one fluid sampling device located in the housing in fluid communication with a said subsea fluid flowline for obtaining a sample of fluid from the subsea fluid flowline; at least one fluid processing apparatus located in the housing in fluid communication with said subsea fluid flowline for receiving and processing a portion of the fluid flowing through said fluid flowline or in fluid communication with the fluid sampling device, for processing the sample of fluid obtained from the subsea fluid flowline for analysis, while keeping the sample of fluid at subsea conditions; a fluid analysis device located in the housing, the fluid analysis device being in fluid communication with the fluid processing device and/or with the fluid sampling device, the fluid analysis de

Abstract: A method for optically sampling characteristics of subsurface fluids within a wellhole using continuous, non-pulsed light transmitted downhole in optical fibers for both sampling and reference light channels for accurate attenuation compensation.

Abstract: A gas separation and detection tool for performing in situ analysis of borehole fluid is described. A separation system such as a membrane is employed to separate one or more target gasses from the borehole fluid. The separated gas may be detected by reaction with another material or spectroscopy. When spectroscopy is employed, a test chamber defined by a housing is used to hold the gas undergoing test. Various techniques may be employed to protect the gas separation system from damage due to pressure differential. For example, a separation membrane may be integrated with layers that provide strength and rigidity. The integrated membrane separation may include one or more of a water impermeable layer, gas selective layer, inorganic base layer and metal support layer. The gas selective layer itself can also function as a water impermeable layer. The metal support layer enhances resistance to differential pressure. Alternatively, the chamber may be filled with a liquid or solid material.

Abstract: Methods and apparatus for decreasing a density of a downhole fluid are described. An example apparatus to analyze a downhole fluid includes a chamber to decrease a density of at least a portion of a sample of a downhole fluid. Additionally, the example apparatus includes a sensor to measure a pressure of at least the portion of the sample in the chamber. Further, the example apparatus includes a fluid measurement unit to measure a characteristic of at least the portion of the sample based on a relationship between the pressure of at least the portion of the sample in the chamber and a predetermined pressure. Further yet, the example apparatus includes a control unit to determine a parameter of the downhole fluid based on the characteristic.

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: A method and system for azimuth measurements using one or more gyro sensors is disclosed. The method includes acquiring a first data from each of the gyro sensors with an input axis aligned to a first angular orientation and acquiring a second data from each of the gyro sensors with the input axis flipped to a second angular orientation opposite to the first angular orientation. An earth rate component at the first angular orientations is determined based on a difference between the first data and the second data to cancel out bias of each of the gyro sensors. The method may include acquiring a third data of the gyro sensor with the input axis aligned to the same angular orientation as the first angular orientation. An average of the first data and the third data may be used instead of the first data for determining the earth rate component.

Abstract: Methods for performing downhole fluid compatibility tests include obtaining an downhole fluid sample, mixing it with a test fluid, and detecting a reaction between the fluids. Tools for performing downhole fluid compatibility tests include a plurality of fluid chambers, a reversible pump and one or more sensors capable of detecting a reaction between the fluids.