Abstract: A method of optimizing production of a hydrocarbon-containing reservoir by measuring low-frequency Distributed Acoustic Sensing (LFDAS) data in the well during a time period of constant flow and during a time period of no flow and during a time period of perturbation of flow and simultaneously measuring Distributed Temperature Sensing (DTS) data from the well during a time period of constant flow and during a time period of no flow and during a time period of perturbation of flow. An initial model of reservoir flow is provided using the LFDAS and DTS data; the LFDAS and DTS data inverted using Markov chain Monte Carlo method to provide an optimized reservoir model, and that optimized profile utilized to manage hydrocarbon production from the well and other asset wells.

Abstract: Aspects of the present disclosure relate generally to analyzing subterranean cylindrical structures using acoustic sensing. On example includes: sending first acoustic waves in the wellbore via a radial acoustic sensor; receiving first reflection waves associated with the first acoustic waves via the radial acoustic sensor; sending second acoustic waves in the wellbore via the radial acoustic sensor; receiving second reflection waves associated with the second acoustic waves via the radial acoustic sensor; processing recorded data associated with the first acoustic waves, the first reflection waves, the second acoustic waves, and the second reflection waves, wherein the first acoustic waves are associated with a first radial direction, and wherein the second acoustic waves are associated with a second radial direction, the second radial direction being opposite the first radial direction; and generating a plot for identification of one or more isolation regions in the wellbore based on the processing.

Abstract: Implementations described and claimed herein provide systems and methods for breaking cement within an annulus of a wellbore. In one implementation, an annulus cement breaking system includes a cement compression tool operable to be disposed within an inner bore of a casing having a longitudinal length. The casing is disposed within a wellbore formed in a subterranean formation having a cement layer disposed within an annulus formed between the casing and the subterranean formation. One or more actuation elements are coupled with the cement compression tool, and the one or more actuation elements are operable to engage the inner bore. The one or more actuation elements are transitionable between an unactuated state and an actuated stated. The actuated state operable to engage the inner bore of the casing, thereby radially expanding the casing and compressing the cement layer.

Abstract: A method for creating access to annular spacing during plug and abandonment operations is described. Specifically, helical coils are cut into one or more casings before the plugging material is set. The plugging material is able to exit the helical coils, forming multiple, small rock-to-rock seals.

Abstract: Gravity driven reverse circulator tools are provided and methods of using same. One tool has nested pipes that when fully nested close a hole in one of the pipes, but when the drillstring is lifted, the pipes partially separate under the force of gravity to expose the hole. The other embodiment is similar, but the hole is hook shaped (hook on top as in a walking cane) and a protrusion from the other pipe fits in the hole. Thus, both lifting and rotation are needed open the tool.

Abstract: The invention relates to a method and system for monitoring strain data on a subsea wellhead and associated tubing especially during a drilling or completion operation when the wellhead is connected via a riser to a drilling rig. The bending stresses on the wellhead assembly can be modelled and monitored, based on strain data from strain gauges attached to the conductor, surface casing and possibly also inner tubing. The strain gauges are located where maximum bending stresses occur, at around seafloor level. Data from the strain gauges is transmitted by radio to a receiver unit on the template, from which it may either be transmitted to the surface or stored and retrieved by divers or subsea vehicles.

Abstract: A method of determining an optimal flare spacing for streamers towed behind a seismic vessel comprising the steps of: using a computer specially adapted with a seismic data analysis package to analyze prior seismic data for a survey area; analyzing migration broadcast patterns to estimate a maximum sampling distance; calculating a wavelet expansion as a function of flare spacing; creating synthetic gaps in the prior seismic data coverage by dropping traces at different flare spacing; testing capability of different interpolation algorithms in the seismic data analysis package to close the synthetic gaps; and determining an optimal flare spacing based upon the capability of the different interpolation algorithms to close the synthetic gaps.

Abstract: A method is provided to determine and mitigate one or more downhole events of a drill string in a wellbore. The method includes receiving, via a processor, drilling data from one or more surface sensors. The drilling data is processed into a plurality of segments. Each of the plurality of segments are processed by a pre-trained model such that one or more labels are determined. The one or more labels are relating to one or more downhole events corresponding to each of the plurality of segments.

Abstract: The present disclosure provides processes for removing hydrocarbons, oil coated solids, and suspended solids from a separated water stream produced from a produced water source. In particular, the methods comprise subjecting the separated water stream to a centrifugal separation followed by filtration.

Abstract: The invention relates to the introduction of pressurized fluid, e.g. acid, into a subsea well directly from a vessel (33). A fluid injection assembly (20) is fitted to the top of a subsea Xmas tree (3), the assembly (20) including fail safe closed valve (21) which is controlled via a hydraulic line (31) from the vessel. The hose and assembly and valve are designed with an internal bore allowing a large diameter ball to be dropped (required for acid stimulation). The subsea subsea control module (8) on the Xmas tree is controlled from the producing platform.

Abstract: A procedure and apparatus for cementing and cleaning a reservoir liner 3 comprises installing a reservoir liner using a drill string 4 which extends only as far as the distal end of a cased part 2 of the well, then, using the drill string, displacing cement into the reservoir liner using completion fluid whereby, when the cement is in place in the annulus around the reservoir liner, the reservoir liner is already clean and filled with completion fluid. A ball valve 6 at the top of the reservoir liner 3 is then closed before the cased part 2 of the wellbore is cleaned, to avoid debris entering the reservoir liner.

Abstract: Systems and method for nuclear magnetic resonance (NMR) well logging use an inversion pulse sequence with a Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence to improve spin magnetization calculations. Improved Bloch equation-based calculations consider conditions where a longitudinal relaxation time and a transverse relaxation time of the hydrogen nuclei (e.g., of a subterranean hydrocarbon pool and/or water) are within an order of magnitude of pulse durations for the inversion pulse sequence and the CPMG pulse sequence. Accordingly, an NMR response to the inversion pulse sequence and the CPMG pulse can be detected and used to calculate one or more spin magnetization values with higher accuracy amplitudes. Reservoir characteristics are determined based on the one or more spin magnetization values. As such, improved well operations (e.g., selecting a drilling site, determining a drilling depth, and the like) can be performed.

Abstract: Implementations described and claimed herein provide apparatus and techniques for providing a seal for a polished rod. One example apparatus is a stuffing box. The stuffing box generally includes: a first flange configured to surround a polished rod; a second flange configured to surround the polished rod; a seal package disposed between the first flange and the second flang, the seal package being configured to surround and connect to the polished rod; and a flexible membrane surrounding the seal package, the flexible membrane being connected to at least a portion of the seal package.

Abstract: A system and method for turning a well over to production. The method may include drilling a wellbore using a drillstring, casing the wellbore, fracturing a reservoir, drilling the wellbore to a plug back total depth using the drillstring to clean out the wellbore, and converting the drillstring from a drilling mode to a production mode.

Abstract: The invention relates to the drilling of wells in rock and hydrocarbon formations. Drilling is performed with a drill string having a bottom hole assembly (BHA) and drill bit. Drilling mud is circulated during drilling. A valved inlet port is provided in the BHA which, in the event of a pack-off, opens and allows drilling mud to enter an internal space in the BHA to relieve pressure. An outlet port at the proximal end of the BHA may be provided to allow the mud to flow back into the annulus around the drill string. In this way, rapid build-up of pressure is avoided and the driller has more time to respond to the pack-off.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: Monitoring and diagnosing completion during hydraulic fracturing operations provides insights into the fracture geometry, inter-well frac hits and connectivity. Conventional monitoring methods (microseismic, borehole gauges, tracers, etc.) can provide a range of information about the stimulated rock volume but may often be limited in detail or clouded by uncertainty. Utilization of DAS as a fracture monitoring tool is growing, however most of the applications have been limited to acoustic frequency bands of the DAS recorded signal. In this paper, we demonstrate some examples of using the low-frequency band of Distributed Acoustic Sensing (DAS) signal to constrain hydraulic fracture geometry. DAS data were acquired in both offset horizontal and vertical monitor wells. In horizontal wells, DAS data records formation strain perturbation due to fracture propagation. Events like fracture opening and closing, stress shadow creation and relaxation, ball seat and plug isolation can be clearly identified.

Abstract: A technique for abandonment of a hydrocarbon well injects cement into the annulus through apertures (5) in the casing (3). The apertures (5) are pre-formed in the casing before the casing is installed at the start of life of the well, and are also fitted with a closure sleeve (6). The apertures (5) remain closed for the lifetime of the well. The closure sleeve (6) is designed to remain operational over the 20-30 year lifetime of the well. When the time comes to plug and abandon the well, a tool (9) is passed down the well on drill pipe (10) to open the apertures (5) by moving the sleeve (6). Wash fluid and then cement are injected from the tool (9) through the apertures (5) to wash and then plug the annulus behind the casing (3).

Abstract: A method for producing heavy oil using solvent injection without gas interference at the electric submersible pump (ESP), the method including completing the injection well with two or more injector tubings, at a heel and toe, and optionally therebetween. Ideally, when gas locking of the ESP is detected, the operator switches to toe dominant injections, mitigating the gas locking problem, and producing oil at a faster rate than possible with evenly distributed injections.

Abstract: A steam-assisted gravity drainage method is described that includes a two stage solvent injection scheme, wherein steam plus solvent injection is followed by steam plus heavier-solvent injection. The two solvent injections improve recoveries of both the heavy oil and the injected solvent while limiting steam requirements, thus improving the economics of the method.