Schlumberger Technology Corporation

Shell Oil Comapny

Bp Exploration, Inc.

Petroleum Physics Corporation

Robert Freedman

Krishnamurthy Ganesan

Vivek Anand

Douglas W Grant

Anatoly Dementyev

Daniel Catina

Payam Tabrizi

Reza Taherian

Nicholas J Heaton

Henry N Bachman

Christopher Edward Morriss

Abdurrahman Sezginer

Robert L Kleinberg

Gerald N Minerbo

Martin D Hurlimann

Chanh Cao Minh

Charles Flaum

Michael M Herron

Luis Eduardo DePavia

Abdel Kharrat

Pierre Henri Campanac

Austin Boyd

Susan L Herron

John E Smaardyk

Yuesheng Cheng

Richard W Gaylor

Tracy E Broussard

David P Madio

Jason P MacInnis

Ricardo Y Torres

John E Puffer

Disclosed herein is a formation evaluation method including estimating a total porosity of an earth formation as a function of bulk density and total nuclear magnetic resonance (NMR) porosity of the earth formation. The total porosity of the earth formation as estimated underrepresents bitumen content. A gas filled porosity of the earth formation is estimated as a function of the bulk density and the total NMR porosity. A kerogen volume of the earth formation is estimated as a function of the gas filled porosity and a total organic carbon content of the earth formation. A bitumen filled total porosity is determined as a function of the estimated kerogen volume and the estimated total porosity of the earth formation. A corrected kerogen volume of the earth formation is determined as a function of the estimated kerogen volume and the estimated total porosity of the earth formation.

Method for formation evaluation of organic shale reservoirs using well logging data

The Larmor frequency for an in situ nuclear magnetic resonance (NMR) tool is determined and used to acquire NMR data. An NMR tool is provided and placed in situ, for example, in a wellbore. An initial estimate of the Larmor frequency for the in situ NMR tool is made and NMR data are acquired using the in situ NMR tool. A spectral analysis is performed on the NMR data, or optionally, the NMR data are digitized and a discrete Fourier transform (DFT) is performed on the digitized NMR data. The modal frequency of the spectral analysis or DFT is determined, and the Larmor frequency for the in situ NMR tool is determined using the modal frequency. The NMR tool is modified to transmit at the determined Larmor frequency and then used to acquire further NMR data.

Determining the Larmor frequency for NMR tools

An apparatus for NMR properties of subsurface formations includes a magnet, a transmitter antenna and at least one of a receiver section of the transmit antenna or a separate receiver antenna having a length along the longitudinal dimension of the apparatus which is shorter than a length of the transmitter antenna along the longitudinal dimension. The apparatus includes circuitry for applying radio frequency current pulses to the entire transmitter antenna and for receiving signals by the at least one of the receiver section of the transmitter antenna and the separate receiver antenna.

Apparatus and methods for fast NMR well logging without instrument speed effects

A method for predicting at least one property of a geological formation may include generating mapping function values relating a plurality of reference elemental compositions to corresponding reference properties thereof based upon at least one non-linear mapping function. The method may further include determining a sample elemental composition of at least one sample associated with the geological formation and performing, using a processor, an interpolation to map the sample elemental composition to at least one sample property based upon the mapping function values and the at least one non-linear function.

Predicting mineralogy properties from elemental compositions

A nuclear magnetic resonance (NMR) measurement system for high pressure and temperature measurements on fluids is disclosed. The system has a sensor assembly that includes a sample holder having a body formed from a non-magnetic metal and defining an interior cavity for receiving a fluid sample, a frame member disposed in the interior cavity of the sample holder, an antenna coil disposed in the interior cavity about the frame member, an inlet that allows the fluid sample to enter the interior cavity, an outlet that allows for the fluid sample to be flushed from the interior cavity, and a magnet assembly having a central bore in which the sample holder is disposed. Adjacent to the sample holder are pulsed field gradient coils for performing diffusion measurements. The system further includes pulse sequencer circuitry that supplies signals to the antenna coil. When the interior cavity of the sample holder is filled with the fluid sample, the antenna coil and the frame member are at least partially submerged in the fluid sample, and the antenna coil obtains NMR measurements of the fluid sample in response to the signals. Related methods and apparatuses are also disclosed herein.

System and method for obtaining nuclear magnetic resonance measurements on reservoir fluids for prediction of fluid properties

Determining the larmor frequency for NMR tools

A downhole micro MR analyzer for use in a wellbore, having a micro sample tube, a micro RF coil in close proximity to the micro sample tube, and one or more magnets disposed about the micro sample tube is disclosed. The micro MR analyzer can be used for nuclear magnetic resonance or electron spin resonance experiments to ascertain formation properties and chemical compositions.

Downhole micro magnetic resonance analyzer

The present invention relates to making one or more measurements in a virgin formation using a downhole tool that includes a miniature logging tool. The downhole tool is disposed in a wellbore penetrating the formation, adjacent to the formation, and a sidetrack borehole is made into the formation. All or a portion of the miniature logging tool is deployed into the sidetrack borehole and measurements are made in the virgin formation using the miniature logging tool. The downhole tool may include a drilling/coring module, a pump module, and packers. The drilling/coring module is used to make the sidetrack borehole, and the packers and pump module can be used to create an underbalanced drilling condition in an isolated section of the wellbore.

Measurements in non-invaded formations

A fluid property of live crude oil removed from an earth formation is determined using nuclear magnetic resonance (NMR) measurements. A pressure cell, located on or near the earth's surface, and in which the live crude oil is disposed, is provided. An NMR tool capable of making NMR measurements on the live crude oil is provided, as is a database linking existing NMR data and the fluid property. A mapping function is created from a combination of radial basis functions and parameters of the mapping function are derived using the database. NMR data are acquired on the live crude oil using the NMR tool, and the fluid property is estimated from the acquired NMR data using the mapping function.

Predicting properties of live oils from NMR measurements

A method for determining wettability of an earth formation zone surrounding a borehole, including the following steps: introducing paramagnetic ions into the water component of the zone; performing NMR measurements on the zone, and determining an NMR relaxation time parameter for the zone; extracting a fluid sample from the zone; performing NMR measurements on the sample, and determining the NMR relaxation time parameter for the sample; and determining wettability of the earth formation zone using the determined relaxation time parameter for the zone and the determined relaxation time parameter for the sample.

Method for determining wettability of an oil reservoir

The present invention pertains to an apparatus and method for conducting magnetic resonance measurements on fluids at high pressures and/or high temperatures. The apparatus can be used in conjunction with or as part of a downhole fluid sampling tool to perform NMR measurements on fluids withdrawn from petroleum reservoirs, or can also be used for laboratory measurements on live reservoir fluids. The apparatus can perform all of the measurements made by modern NMR logging tools, including multi-dimensional distribution functions of spin-spin (T) and spin-lattice relaxation (T) times and molecular diffusion coefficients. The spin densities of hydrogen and other NMR sensitive species can be computed from the distribution functions. The apparatus can also be used to predict the apparent conductivity of the fluids in the flowline from measurements of the quality factor ('Q') of the NMR circuit. The apparent conductivity can be used to predict water cut or water salinity.

High pressure/high temperature magnetic resonance tool

An apparatus and method to perform measurements on fluid in a wellbore fluid sample tool in which at least a portion of the flowline of the sample tool is made of a non-magnetic and non-conductive material.

Non-conductive and non-magnetic flowline for electromagnetic measurements on reservoir fluids at high pressures

A method for determining a property of earth formations surrounding a borehole includes the following steps: deriving a fluid sample downhole in the borehole, subjecting the sample while downhole to a magnetic field; measuring a magneto-optical shift of a beam of electromagnetic radiation passed through the sample, and determining the property from the measured magneto-optical shift.

Magneto-optical method and apparatus for determining properties of reservoir fluids

A method for determining a characteristic of earth formations from measurements taken on the formations, includes the following steps: producing a data base that includes a multiplicity of data points, each data point representing a stored formation characteristic output related to a stored input measurement; deriving, from the data base, a mapping function; deriving an input formation measurement value; and determining an output formation characteristic value from the data base, the mapping function, and the input formation measurement value.

Method for determining characteristics of earth formations

A method for estimating a concentration of a substance in a test sample of formation fluid, comprising measuring an NMR parameter of a first sample of formation fluid to obtain a first measurement, adding a known quantity of the substance to the first sample to produce a modified sample, measuring the NMR parameter of the modified sample to obtain a second measurement; and determining a relation between the concentration of the substance and a function of the NMR parameter using the first and second measurements and the NMR parameter of the substance.

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Houston, TX, United States of America

Robert Freedman