Schlumberger Technology Corporation

Other

Lukasz Zielinski

Yi-Qiao Song

Ravinath Kausik Kadayam Viswanathan

Lalitha Venkataramanan

Martin D Hurlimann

Denise E Freed

Martin D Hürlimann

Robert L Kleinberg

Mehmet Parlar

Andrew Clarke

Chanh Cao Minh

Andrew Meredith

Gerald Henry Meeten

Ridvan Akkurt

Shin Utsuzawa

Edmund John Fordham

Jonathan Mitchell

Valerie Judith Anderson

Robert Callan

Timothy Andrew John Hopper

Haitao Zhang

Marcus Hofheins Donaldson

Baarinadh Vissapragada

Nicholas A Bennett

Rajesh A Chanpura

Aqueous liquid which has been in contact with a subterranean geological formation, especially a hydrocarbon reservoir, is examined in order to detect or measure viscosifying polymer therein, by flowing a sample of the liquid through a constriction thereby causing extensional flow and alignment of any polymer molecules with the flow, and examining the solution for birefringence of aligned polymer molecules. The amount of birefringence is determined from intensity of light which has passed through the solution relative to intensity of the light source.

Oilfield monitoring of subterranean polymer solution

Methods for improved interpretation of NMR data acquired from industrial samples by simultaneously detecting more than one resonant nucleus without removing the sample from the sensitive volume of the NMR magnet or radio frequency probe are disclosed. In other aspects, the present disclosure provides methods for robust imaging/analysis of spatial distribution of different fluids (e.g., 1H, 23Na, 19F) within a core or reservoir rock. NMR data may be interpreted in real-time during dynamic processes to enable rapid screening, e.g. of enhanced oil recovery techniques and products and/or to provide improved interpretation of well-logs. Measurements of resonant nuclei other than 1H may be performed in the laboratory or downhole with a NMR logging tool. In other aspects, the present disclosure describes a novel kernel function to extract values for underlying parameters that define relaxation time behavior of a quadrupolar nucleus.

Methods for interpreting NMR data

A method for correcting motion-effects from a downhole measurement includes, in one embodiment, determining relative motion of a downhole logging tool for a given logging operation in a borehole formed in an earth formation, determining a motion induced signal decay (MID) based upon the determined relative motion, determining a motion-effect inversion kernel (MEK) based upon the determined MID, using the downhole logging tool to acquire measurements that are affected by motion of the downhole logging tool during the logging operation, and using the MEK to process the acquired motion-affected measurements to obtain motion-corrected data. Corresponding systems, devices, and apparatuses are also disclosed herein.

Correction of motion effect in nuclear magnetic resonance (NMR) logging

Systems and methods are provided for investigating a downhole formation using a nuclear magnetic resonance (NMR) tool having two or more radio frequency receiving coils. While the tool is moving through the borehole, the formation is magnetized and resulting signals are obtained. In accordance with the present approach, the acquired signals can be resolved azimuthally and can be reconstructed to obtain an indication of a parameter of the formation at multiple locations along the length of the borehole.

Imaging subterranean formations and features using multicoil NMR measurements

Apparatus and methods for characterizing hydrocarbons in a subterranean formation include obtaining a sample of the subterranean formation; measuring, uphole, the porosity of the sample; using a nuclear magnetic resonance (NMR) tool downhole in the borehole, sending NMR pulse sequences configured for formation pore size and measuring NMR signals that characterize the formation at a location in the formation; analyzing the signals to find a gas porosity of the formation at the location; and determining a hydrogen index (HI) of the subterranean formation from the gas porosity and from the porosity of the sample. The obtained HImay then be used in conjunction with downhole NMR measurements to find corrected gas porosities at locations of the formation.

Logging in gas shale and other unconventional reservoirs

An NMR method and apparatus for analyzing a sample of interest applies a static magnetic field together with RF pulses of oscillating magnetic field across a sample volume that encompasses the sample of interest. The RF pulses are defined by a pulse sequence that includes a plurality of measurement segments configured to characterize a plurality of relaxation parameters related to relaxation of nuclear magnetization of the sample of interest. Signals induced by the RF pulses are detected in order to derive the relaxation parameters. The measurement segments of the pulse sequence include at least one first-type measurement segment configured to characterize relaxation of spin-lattice interaction between nuclei of the sample of interest in a rotating frame (T) at a predefined frequency. The Tparameter can be measured in conjunction with the measurement of other relaxation and/or diffusion parameters as part of multidimensional NMR experiments.

Rotating frame pulsed nuclear magnetic resonance spectroscopy

Methods and apparatuses are provided for analyzing a composition of a hydrocarbon-containing fluid. The methods include using a nuclear magnetic resonance (NMR) tool to conduct an NMR measurement on the hydrocarbon-containing fluid to obtain NMR data. A non-NMR tool, such as an optical tool, is used to conduct additional measurements on the hydrocarbon-containing fluid and to obtain non-NMR data on the fluid. An indication of the composition of the fluid can be determined by using the NMR data and the non-NMR data in an inversion process.

Methods for compositional analysis of downhole fluids using data from NMR and other tools

Methods for the determination of the Total Gas in Place (TGiP) in gas-bearing formations are provided. Aspects of the subject disclosure also relate to the determination of the TGiP from nuclear magnetic resonance (NMR) logs alone or in combination other well logs.

Multiphysics NMR logging techniques for the determination of in situ total gas in gas reservoirs

Estimating and displaying information about the size of molecules within a substance from nuclear magnetic resonance (NMR) maps and/or logs. Methods include utilizing a relationship between the molecular size (e.g., mean chain length), and either a moment of diffusion or a relaxation distribution, to create a scale on a two-dimensional map. In one case, applying the relationship between the molecular size, and either a moment of diffusion or a relaxation distribution, to one-dimensional diffusion or relaxation distributions for the purpose of estimating the mean chain length of molecules within the substance. In another case, a method includes determining mean chain lengths of molecules within a substance and providing a one-dimensional NMR log showing the mean chain lengths at a plurality of depths. In some cases, the NMR log includes actuatable regions for examining two-dimensional NMR maps or chain length distributions of the substance corresponding with distinct depths of the substance.

Estimating and displaying molecular size information of a substance

A method for determining particle size distribution of a subsurface rock formation using measurements of at least one nuclear magnetic resonance property made from within a wellbore penetrating the rock formation includes determining a distribution of nuclear magnetic relaxation times from the measurements of the at least one nuclear magnetic resonance property. A surface relaxivity of the formation is determined from measurements of a formation parameter. The relaxation time distribution and surface relaxivity are used to determine the particle size distribution.

Growing community of inventors

Cambridge, United Kingdom

Lukasz Zielinski