Patents by Inventor Lalitha Venkataramanan

Lalitha Venkataramanan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9222902
    Abstract: A nuclear magnetic resonance (NMR) related distribution is estimated that is consistent with NMR measurements and uses linear functionals directly estimated from the measurement indications by integral transforms as constraints in a cost function. The cost function includes indications of the measurement data, Laplace transform elements and the constraints, and a distribution estimation is made by minimizing the cost function. The distribution estimation may be used to find parameters of the sample. Where the sample is a rock or a formation, the parameters may include parameters such as rock permeability and/or hydrocarbon viscosity, bound and free fluid volumes, among others. The parameters may be used in models, equations, or otherwise to act on the sample, such as in recovering hydrocarbons from the formation.
    Type: Grant
    Filed: January 9, 2012
    Date of Patent: December 29, 2015
    Assignee: Schlumberger Technology Corporation
    Inventors: Fred K. Gruber, Lalitha Venkataramanan, Tarek M. Habashy, Philip M. Singer, Denise E. Freed
  • Publication number: 20150177351
    Abstract: A methods are provided for investigating a sample containing hydrocarbons by subjecting the sample to a nuclear magnetic resonance (NMR) sequence using NMR equipment, using the NMR equipment to detect signals from the sample in response to the NMR sequence, analyzing the signals to extract a distribution of relaxation times (or diffusions), and computing a value for a parameter of the sample as a function of at least one of the relaxation times (or diffusions), wherein the computing utilizes a correction factor that modifies the value for the parameter as a function of relaxation time for at least short relaxation times (or as a function of diffusion for at least large diffusion coefficients).
    Type: Application
    Filed: May 24, 2013
    Publication date: June 25, 2015
    Applicant: Schlumberger Technology Corporation
    Inventors: Lalitha Venkataramanan, Fred K. Gruber, Tarek M. Habashy, Ridvan Akkurt, Badarinadh Vissapragada, Richard E. Lewis, Erik Rylander
  • Publication number: 20150168585
    Abstract: Apparatus and methods of analyzing a composition of a hydrocarbon-containing fluid including using a nuclear magnetic resonance (NMR) tool to conduct a NMR relaxation measurement, a diffusion measurement, or both on the hydrocarbon-containing fluid to obtain NMR data, using a non-NMR tool to conduct an additional measurement of a reference fluid to obtain non-NMR data wherein the additional measurement comprises gas chromatography, optical observation, or both, and using the NMR data and the non-NMR data in an inversion process to determine an indication of the composition of the hydrocarbon-containing fluid. In some embodiments, the indication is determined over 4 chain length nodes.
    Type: Application
    Filed: December 17, 2013
    Publication date: June 18, 2015
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: NICHOLAS N. BENNETT, YI ZENG, LALITHA VENKATARAMANAN, DENISE E. FREED, MARTIN D. HÜRLIMANN
  • Publication number: 20150168586
    Abstract: 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.
    Type: Application
    Filed: December 17, 2013
    Publication date: June 18, 2015
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Denise E. FREED, Yi-Qiao SONG, Lalitha VENKATARAMANAN, Lukasz ZIELINSKI, Nicholas A. BENNETT, Martin D. HÜRLIMANN
  • Publication number: 20150168587
    Abstract: 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 NMR measurements on the hydrocarbon-containing fluid to obtain NMR data. A non-NMR tool, such as an optical tool, is used to conduct additional measurements and to obtain non-NMR data on the fluid. The methods further include determining an indication of the composition of the fluid by using the NMR data and normalizing the indication of the composition of the fluid using the non-NMR data.
    Type: Application
    Filed: December 17, 2013
    Publication date: June 18, 2015
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: DENISE E. FREED, LALITHA VENKATARAMANAN
  • Publication number: 20140380134
    Abstract: A method of obtaining nuclear magnetic resonance (NMR) data from a subterranean formation may include operating a tool in a subterranean formation for generating both NMR data and NMR scaled data based upon NMR measurements of the subterranean formation. The method may also include operating the tool for encoding and transmitting both the NMR data and NMR scaled data, and receiving and decoding, above the subterranean formation, both the NMR data and NMR scaled data from the tool. The method may also include performing error-correction of the received and decoded NMR data based upon the received and decoded NMR scaled data.
    Type: Application
    Filed: January 30, 2013
    Publication date: December 25, 2014
    Inventors: Nicholas N. Bennett, Lalitha Venkataramanan, Nicholas Heaton
  • Publication number: 20140229112
    Abstract: Adsorbed gas in a formation may be estimated. Nuclear magnetic resonance (NMR) data for a subsurface geological formation is obtained, and at least a portion of the NMR data is corrected to produce corrected NMR data. A NMR-based estimate of formation porosity is determined using the corrected NMR data. Dielectric permittivity data for the subsurface geological formation is obtained, and a dielectric permittivity-based estimate of the formation water-filled porosity is determined using the dielectric permittivity data. A gas volume is determined using the determined NMR-based estimate of the formation porosity and the determined dielectric permittivity-based estimate of the formation water-filled porosity. The gas volume may be determined by subtracting the determined dielectric permittivity-based estimate of the formation water-filled porosity from the determined NMR-based estimate of the formation porosity. The gas volume per unit volume of the formation may be determined using an equation of state.
    Type: Application
    Filed: February 14, 2013
    Publication date: August 14, 2014
    Applicant: Schlumberger Technology Corporation
    Inventors: Ashish Datey, Timothy Andrew John Hopper, Lalitha Venkataramanan
  • Publication number: 20140074405
    Abstract: Methods and related systems are described for estimating fluid or rock properties from NMR measurements. A modified pulse sequence is provided that can directly provide moments of relaxation-time or diffusion distributions. This pulse sequence can be adapted to the desired moment of relaxation-time or diffusion coefficient. The data from this pulse sequence provides direct estimates of fluid properties such as average chain length and viscosity of a hydrocarbon. In comparison to the uniformly-spaced pulse sequence, these pulse sequences are faster and have a lower error bar in computing the fluid properties.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 13, 2014
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: LALITHA VENKATARAMANAN, TAREK M. HABASHY, DENISE E. FREED, ASHOK BELANI
  • Patent number: 8612193
    Abstract: In accordance with an embodiment of the present invention, a method of processing large volumes of data to allow for real-time reservoir management is disclosed, comprising: a) acquiring a first data series from a first reservoir sensor; b) establishing a set of criteria based on reservoir management objectives, sensor characteristics, sensor location, nature of the reservoir, and data storage optimization, etc.; c) identifying one or more subsets of the first data series meeting at least one of the criteria; and optionally d) generating one or more second data series based on at least one of the subsets. This methodology may be repeated for numerous reservoir sensors. This methodology allows for intelligent evaluation of sensor data by using carefully established criteria to intelligently select one or more subsets of data. In an alternative embodiment, sensor data from one or more sensors may be evaluated while processing data from a different sensor.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: December 17, 2013
    Assignee: Schlumberger Technology Center
    Inventors: Bhavani Raghuraman, Terizhandur S. Ramakrishnan, Kenneth E. Stephenson, Lalitha Venkataramanan, Jose Navarro
  • Patent number: 8587302
    Abstract: Methods and related systems are described for estimating fluid or rock properties from NMR measurements. A modified pulse sequence is provided that can directly provide moments of relaxation-time or diffusion distributions. This pulse sequence can be adapted to the desired moment of relaxation-time or diffusion coefficient. The data from this pulse sequence provides direct estimates of fluid properties such as average chain length and viscosity of a hydrocarbon. In comparison to the uniformly-spaced pulse sequence, these pulse sequences are faster and have a lower error bar in computing the fluid properties.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: November 19, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Lalitha Venkataramanan, Tarek M. Habashy, Denise Freed, Ashok Belani
  • Publication number: 20130179083
    Abstract: A nuclear magnetic resonance (NMR) related distribution is estimated that is consistent with NMR measurements and uses linear functionals directly estimated from the measurement indications by integral transforms as constraints in a cost function. The cost function includes indications of the measurement data, Laplace transform elements and the constraints, and a distribution estimation is made by minimizing the cost function. The distribution estimation may be used to find parameters of the sample. Where the sample is a rock or a formation, the parameters may include parameters such as rock permeability and/or hydrocarbon viscosity, bound and free fluid volumes, among others. The parameters may be used in models, equations, or otherwise to act on the sample, such as in recovering hydrocarbons from the formation.
    Type: Application
    Filed: January 9, 2012
    Publication date: July 11, 2013
    Inventors: FRED K. GRUBER, LALITHA VENKATARAMANAN, TAREK M. HABASHY, PHILIP M. SINGER, DENISE E. FREED
  • Publication number: 20130060474
    Abstract: Apparatus and method of characterizing a subterranean formation including observing a formation using nuclear magnetic resonance measurements, calculating an answer product by computing an integral transform on the indications in measurement-domain, and using answer products to estimate a property of the formation. Apparatus and a method for characterizing a subteranean formation including collecting NMR data of a formation, calculating an answer product comprising the data, wherein the calculating comprises a formula K ? ( x ) ? ? 0 ? ? k ? ( t ) ? ? - t / x ? ? t . and estimating a property of the formation using the answer product.
    Type: Application
    Filed: December 21, 2011
    Publication date: March 7, 2013
    Inventors: LALITHA VENKATARAMANAN, TAREK M. HABASHY, FRED K. GRUBER, DENISE E. FREED
  • Publication number: 20130002246
    Abstract: Methods and related systems are described for estimating fluid or rock properties from NMR measurements. A modified pulse sequence is provided that can directly provide moments of relaxation-time or diffusion distributions. This pulse sequence can be adapted to the desired moment of relaxation-time or diffusion coefficient. The data from this pulse sequence provides direct estimates of fluid properties such as average chain length and viscosity of a hydrocarbon. In comparison to the uniformly-spaced pulse sequence, these pulse sequences are faster and have a lower error bar in computing the fluid properties.
    Type: Application
    Filed: July 6, 2012
    Publication date: January 3, 2013
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Lalitha VENKATARAMANAN, Tarek M. HABASHY, Denise E. FREED
  • Publication number: 20120125602
    Abstract: A method of monitoring a nonhydrocarbon and nonaqueous fluid injected into the earth's subsurface through a first wellbore that involves positioning a fluid analysis tool within a second wellbore and determining the presence of the injected nonhydrocarbon and nonaqueous fluid by making a measurement downhole on the injected nonhydrocarbon and nonaqueous fluid using the fluid analysis tool. Also a related method of enhancing hydrocarbon production from a subsurface area having first and second wellbores that involves injecting a nonhydrocarbon and nonaqueous fluid into the subsurface through the first wellbore, positioning a fluid analysis tool within the second wellbore, and determining the presence of the injected nonhydrocarbon and nonaqueous fluid by making a measurement downhole on the injected nonhydrocarbon and nonaqueous fluid using the fluid analysis tool.
    Type: Application
    Filed: October 10, 2011
    Publication date: May 24, 2012
    Inventors: Francois Dubost, Oliver C. Mullins, Lalitha Venkataramanan, Christopher Harrison, Neil Bostrom, Robert Kleinberg
  • Publication number: 20110215802
    Abstract: Methods and related systems are described for estimating fluid or rock properties from NMR measurements. A modified pulse sequence is provided that can directly provide moments of relaxation-time or diffusion distributions. This pulse sequence can be adapted to the desired moment of relaxation-time or diffusion coefficient. The data from this pulse sequence provides direct estimates of fluid properties such as average chain length and viscosity of a hydrocarbon. In comparison to the uniformly-spaced pulse sequence, these pulse sequences are faster and have a lower error bar in computing the fluid properties.
    Type: Application
    Filed: March 4, 2010
    Publication date: September 8, 2011
    Applicant: Schlumberger Technology Corporation
    Inventors: LALITHA VENKATARAMANAN, Tarek M. Habashy, Denise Freed, Ashok Belani
  • Patent number: 7674624
    Abstract: A preferred method for determining the flow fraction of a mixture of water, gas and oil in a hydrocarbon reservoir includes measuring pressure and density of the mixture over time, determining a function which approximates a relationship between the density and pressure measurements, calculating a derivative of the function over time, and determining flow fraction based, in part, on the derivative. Preferably, transient data points are eliminated and the remaining set of data points are weight averaged to improve signal to noise ratio. Bubble point pressure, bubble point density and molecular weight and density of the liquid portion of the mixture are also used in the determination.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: March 9, 2010
    Assignee: Schlumberger Technology Corporation
    Inventors: Kenneth E. Stephenson, Lalitha Venkataramanan
  • Publication number: 20090173494
    Abstract: A technique is provided to determine a flow rate of a production fluid. The technique is utilized in a well having a gas lift system. Temperatures are measured along the well to create a temperature profile. The temperature profile is used to determine the flow rate of a produced fluid.
    Type: Application
    Filed: October 18, 2007
    Publication date: July 9, 2009
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Jeffrey A. Tarvin, Lalitha Venkataramanan, Thomas M. White, George A. Brown
  • Patent number: 7398159
    Abstract: Methods and systems are provided for downhole analysis of formation fluids by deriving differential fluid properties and associated uncertainty in the predicted fluid properties based on downhole data less sensitive to systematic errors in measurements, and generating answer products of interest based on the differences in the fluid properties. Measured data are used to compute levels of contamination in downhole fluids using, for example, 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 robust, real-time answer products relating to the formation fluids and reservoirs thereof. Systematic errors in measured data are reduced or eliminated by preferred sampling procedures.
    Type: Grant
    Filed: August 18, 2005
    Date of Patent: July 8, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: Lalitha Venkataramanan, Oliver C. Mullins, Ricardo Reves Vasques
  • Publication number: 20080135237
    Abstract: A method of monitoring a nonhydrocarbon and nonaqueous fluid injected into the earth's subsurface through a first wellbore that involves positioning a fluid analysis tool within a second wellbore and determining the presence of the injected nonhydrocarbon and nonaqueous fluid by making a measurement downhole on the injected nonhydrocarbon and nonaqueous fluid using the fluid analysis tool. Also a related method of enhancing hydrocarbon production from a subsurface area having first and second wellbores that involves injecting a nonhydrocarbon and nonaqueous fluid into the subsurface through the first wellbore, positioning a fluid analysis tool within the second wellbore, and determining the presence of the injected nonhydrocarbon and nonaqueous fluid by making a measurement downhole on the injected nonhydrocarbon and nonaqueous fluid using the fluid analysis tool.
    Type: Application
    Filed: May 25, 2007
    Publication date: June 12, 2008
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Francois Dubost, Oliver C. Mullins, Lalitha Venkataramanan, Christopher Harrison, Neil Bostrom, Robert Kleinberg
  • Publication number: 20080040086
    Abstract: Formation fluid data based on measurements taken downhole under natural conditions is utilized to help identify reservoir compartments. A geological model of the reservoir including expected pressure and temperature conditions is integrated with a predicted fluid model fitted to measured composition and PVT data on reservoir fluid samples or representative analog. Synthetic downhole fluid analysis (DFA) logs created from the predictive fluid model can be displayed along the proposed borehole trajectory by geological modeling software prior to data acquisition. During a downhole fluid sampling operation, actual measurements can be displayed next to the predicted logs. If agreement exists between the predicted and measured fluid samples, the geologic and fluid models are validated. However, if there is a discrepancy between the predicted and measured fluid samples, the geological model and the fluid model need to be re-analyzed, e.g., to identify reservoir fluid compartments.
    Type: Application
    Filed: August 1, 2007
    Publication date: February 14, 2008
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Soraya Betancourt, Oliver Mullins, Rimas Gaizutis, ChengGang Xian, Peter Kaufman, Francois Dubost, Lalitha Venkataramanan