Baker Hughes Corporation

Baker Hughes, a Ge Compnay, LLC

W Allen Gilchrist, Jr

Feyzi Inanc

Darryl E Trcka

Songhua Chen

Thomas Kruspe

Daniel T Georgi

Ole G Engels

Randolph J Walser

David M Chace

Richard R Pemper

Elton Frost, Jr

Rafay Zahid Ansari

Xiaogang Han

Sergey Efremov

Ole Engels

Mike Gillen

Michael E Gillen

Alfred I Khisamutdinov

A method of estimating at least one property of an earth formation includes: constructing a matrix model of a formation; constructing a shale model of the formation, the shale model including an estimation of a concentration of at least one trace element; combining the first model and the second model to generate a formation model; and comparing measured pulsed neutron data with the mixed model to estimate the at least one property.

Apparatus and method for pulsed neutron measurement

A method for estimating a concentration of carbon dioxide (CO) in a formation penetrated by a borehole, the method includes: conveying a carrier through the borehole; irradiating the formation with neutrons from a neutron source disposed at the carrier; detecting photons from the formation resulting from the irradiating; and estimating the concentration of COfrom data acquired from the detecting.

[object Object]

An instrument for performing measurements downhole, includes an irradiator oriented to irradiate sub-surface materials surrounding the instrument, the irradiator including at least one neutron source disposed proximate to a moderator for providing a source of inelastic gamma photons and also disposed proximate to a material for providing a source of capture gamma photons; and a first detector and a second detector, each detector for detecting gamma rays and oriented in a relationship to the irradiator for receiving gamma photons from at least one of the irradiator and the formation. A method for irradiating sub-surface materials is provided.

Gamma ray generator

A method for performing a measurement of a property downhole includes: using an instrument including an irradiator including a pulsed neutron generator, a moderator and a material including a high cross section for capturing thermal neutrons downhole, generating inelastic gamma photons from neutron interactions in the moderator and generating capture gamma photons from neutron interactions in the material; irradiating sub-surface materials proximate to the instrument with the inelastic gamma photons and the capture gamma photons; detecting radiation scattered by the sub-surface materials; and estimating the property according to the detected radiation. A system is also disclosed.

Method for taking gamma-gamma density measurements

A method for estimating information about a formation, the method including obtaining a first set of radiation data substantially influenced by the formation and non-formation materials; obtaining a second set of radiation data substantially influenced by the non-formation materials; and correcting the first set of radiation data with the second set of radiation data to provide corrected formation radiation data.

Compensated mineralogy tool and processing

Data from a string of multiple formation evaluation data sensor are evaluated by an expert system. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed. Alternatively, the sensitive volume of a NMR sensor is altered based on a determination of a fraction of the sensitive volume that includes a borehole fluid. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Automatic adjustment of NMR pulse sequence to optimize SNR based on real time analysis

A method for measuring radiation, the method includes selecting at least two radiation detectors, each detector having a spatial resolution that differs from the spatial resolution of other detectors; measuring the radiation with the detectors; and combining a response from at least two of the detectors to produce a composite response exhibiting a spatial resolution.

Method and apparatus for high resolution gamma ray measurements

Measurements made with a nuclear logging tool are partitioned into bins to provide an energy spectrum. The energy spectrum is calibrated by maximizing a measure of similarity with a reference spectrum.

Method of calibrating multi-channel nuclear energy spectra

Data acquired using a pulsed nuclear source are susceptible to two sources of error. One error is due to large statistical noise towards the end of an acquisition window. Another source of error is the contamination of the early portion of the data by borehole and other effects. The beginning of the processing window is adjusted based on the signal level at the end of the processing window for the preceding pulsing of the source. The end of the processing window is derived from statistical considerations.

Method and apparatus for determining the thermal neutron capture cross-section of a subsurface formation from a borehole

Data from a string of multiple formation evaluation data sensor are evaluated by an expert system. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed. Alternatively, the sensitive volume of a NMR sensor is altered based on a determination of a fraction of the sensitive volume that includes a borehole fluid.

A pulsed neutron source is used in a density logging tool with three or more detectors. This enables compensation for source variations and provides redundant measurements that are used to make borehole corrections and/or corrections for casing.

Method and apparatus for an improved formation density indicator using pulsed neutron instruments

Data from a string of multiple formation evaluation data sensor are evaluated. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed.

Growing community of inventors

Houston, TX, United States of America

W Allen Gilchrist, Jr