Abstract: A method of plugging a well extending into a formation to facilitate temporary or permanent abandonment of the well. The method includes conveying a plug placement and verification tool (PPVT) through the well, to a plug formation location, the PPVT including a stinger for delivering a plugging material into the well, an expandable packer disposed at one end of the stinger and a pressure sensor disposed below the expandable packer, and operating the expandable packer to form a seal in the well above the pressure sensor. The method further includes delivering a plugging material from the stinger into a region of the well above the expandable packer, thereby forming a plug in the well, and thereafter creating a pressure change above the plug and verifying the integrity of the plug using the pressure sensor.

Abstract: A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

Abstract: A method of fluid substitution, wherein an initial data set is provided, wherein a substituted data set is provided, wherein a rock physics model is provided, wherein the initial data set includes initial data of a geophysical parameter and initial fluid data, and wherein the substituted data set includes substituted fluid data. The method includes using the model and the initial data set to calculate first calculated data of the geophysical parameter, using the model and the substituted data set to calculate second calculated data of the geophysical parameter, calculating the difference between the first calculated data of the geophysical parameter and the second calculated data of the geophysical parameter, and applying the difference to the initial data of the geophysical parameter to produce substituted data of the geophysical parameter.

Abstract: There is provided an apparatus (30) and method for conditioning the flow of a mixed phase flow from a supply pipe (101) from a hydrocarbon well. The apparatus (30) comprises an elongate reservoir (11) having a first end for receiving a multi-phase fluid flow from the supply pipe and a second closed end, there being provided a gas outlet (02) from the upper part of the first end, a liquid separation region downstream of the first end, and a liquid outlet (12) from the lower part of the liquid separation region; and a gas-liquid mixer to which the gas and liquid outlets are connected such that the separated gas and liquid may be recombined. The reservoir (11) may accommodate surges of liquid such that the flow rate from the liquid outlet is relatively invariant over time compared to that of the flow received by the apparatus.

Abstract: A method for managing metal naphthenates in produced hydrocarbons includes injecting acid and/or sour gas into produced hydrocarbons in a production well, flowline or riser, to thereby control the pH of fluids contained in the produced hydrocarbons.

Abstract: A method for desalting produced hydrocarbons includes injecting reduced-salinity water into produced hydrocarbons in a production well or riser, to dilute high-salinity produced water contained in the produced hydrocarbons.

Abstract: A method of redatuming geophysical data, wherein there is provided multi-component geophysical data, and the method includes obtaining at least one focussing function and/or at least one Green's function from the multi-component geophysical data.

Abstract: A tool for use in a borehole to perform a milling, under reaming, or other cutting operation includes a tool body configured for rotation about its longitudinal axis, within the borehole, and a set of cutters, the set including two or more cutters which, at least in a deployed configuration, extend outwardly from the tool body and are fixedly coupled together whilst being pivotally coupled to the tool body substantially on said axis so that the cutters rotate with the tool body whilst being pivotable together relative to the tool body during cutting.

Abstract: A method of cleaning deposited solid material from a fouled portion of a gas compressor whilst the gas compressor is in situ in a natural gas processing system is provided. The method comprises the steps of supplying a liquid cleaning agent to a gas inlet of the gas compressor, the liquid cleaning agent being capable of removing the deposited solid material; passing the liquid cleaning agent through the gas compressor to a gas outlet of the gas compressor, wherein at least a portion of the cleaning agent remains in a liquid state as it passes through the fouled portion of the gas compressor; and recovering a fluid containing removed material that is output from the gas compressor so as to prevent the removed material reaching one or more gas processing stages of the gas processing system downstream of the gas compressor.

Abstract: A method of plugging a well includes lowering a solid body into a wellbore by wireline; and filling the space around the solid body with a liquid plugging material. The solid body and the liquid plugging material together form a plug after the liquid plugging material is set.

Abstract: A subsea wellhead assembly and a method of installing a subsea well head assembly. The subsea wellhead assembly includes: a conductor; a subsea wellhead; and subsea riser system equipment mounted on the subsea wellhead. The subsea riser system equipment is connected to the conductor such that forces can be transmitted from the subsea riser equipment to the conductor in both tension and compression.

Abstract: A method of seismic modeling using an elastic model, the elastic model including a grid having a grid spacing sized such that, when synthetic seismic data is generated using the elastic model, synthetic shear wave data exhibits numerical dispersion, the method including: generating generated synthetic seismic data using the elastic model, wherein the generated synthetic seismic data includes synthetic compression wave data and synthetic shear wave data, and modifying the generated synthetic seismic data to produce modified synthetic seismic data by attenuating at least some of the synthetic shear wave data in order to attenuate at least some of the numerically dispersive data.

Abstract: An offshore oil and gas platform has a power supply system with a cascaded arrangement for a black start. The power supply system includes a first power supply apparatus for providing power at a first energy level, an uninterruptible power supply arrangement configured to receive power from the first power supply apparatus, wherein the uninterruptible power supply is for powering at least one essential and/or safety critical component, and a second power supply apparatus for providing power at a second energy level to a main power distribution system, wherein the second energy level is higher than the first energy level, wherein the second power supply apparatus includes a power source and a high-power energy storage system capable of supplying power at the second energy level, and wherein the second power supply apparatus can receive and store energy from the first power supply apparatus.

Abstract: A method of at least partially deghosting recorded seismic s-waves, wherein recorded seismic data is provided, wherein the recorded seismic data has been recorded at a receiver located beneath the Earth's surface, and wherein the recorded seismic data includes s-wave data. The method may include the steps of finding a model of the Earth's crust for use in deghosting the recorded seismic data using the s-wave data, wherein the model includes at least one region and wherein the model includes the Earth's surface and the location of the receiver, using the model to find a deghosting operator that, when applied to the s-wave data, at least partially deghosts the s-wave data, and applying the deghosting operator to the s-wave data to at least partially deghost the s-wave data.

Abstract: Apparatus for monitoring the quality of gas in a process stream at a subsea location comprises: a container for permanent installation at the location; one or more devices for analysing gas quality, said devices being located in the container; and means for supplying a sample of gas from the process stream to the said one or more devices; wherein the pressure within the container is maintained at or near to atmospheric pressure. The invention also extends to a method of monitoring the quality of gas in a process stream at a subsea location.

Abstract: A system for providing information on production value and/or emissions of a hydrocarbon production system is disclosed. The system includes: a plurality of sensors configured to measure a respective plurality of measured parameters of the hydrocarbon production system; an input interface for inputting a plurality of specified parameters into the system; and a processor configured to determine the production value and/or the emissions of the hydrocarbon production system in real time based upon the measured parameters and the specified parameters.

Abstract: Methods of Enhanced Oil Recovery (EOR) from an oil reservoir by CO2 flooding are disclosed. One method comprises producing a well stream from the reservoir; separating the well stream into a liquid phase and a gas phase with a first gas/liquid separator, wherein the gas phase comprises both CO2 gas and hydrocarbon gas; cooling the gas phase with a first cooler; compressing the gas phase using a first compressor into a compressed stream; mixing the compressed stream with an external source of CO2 to form an injection stream; and injecting the injection stream into the reservoir. Systems for EOR from an oil reservoir by CO2 flooding are also disclosed.

Abstract: A method of starting up flow of viscous oil in a pipeline, wherein the pipeline has an inlet and an outlet and wherein the viscous oil is initially stationary within the pipeline, includes supplying water to a first section of the pipeline through an inflow control device; initiating a flow of viscous oil within the first section towards the outlet by pressurising the water; supplying water to a second section of the pipeline through a further inflow wherein the first section is closer to the outlet of the pipeline than the second section; and initiating a flow of viscous oil within the second section towards the outlet by pressurising the water.

Abstract: A method of processing a fluid produced from a well, the produced fluid being a high pressure fluid, the method comprising: reducing the pressure of the fluid to a reduced pressure such that a gas phase and a liquid phase are formed; separating the gas phase from the liquid phase thus forming a gas product and a liquid product; and storing the liquid product in a storage tank at a pressure such that the liquid product remains in a stable liquid phase during storage, wherein the reduced pressure is greater than atmospheric pressure.

Abstract: A system for hydraulically controlling a subsea device includes a compensator provided within a cavity of a well system, a hydraulic connection between the compensator and the subsea device, a pressure regulator arranged to regulate the hydraulic pressure provided to the subsea device and a ventilation tool for releasing pressure at the subsea device.