Challenges in Well LoggingChallenges in Well Logging80 years after Pechelbron 780 years after Pechelbron 7

Mauro GonfaliniMauro GonfaliniSPE Italian SectionSPE Italian Section

June 10, 2004June 10, 2004

22

Key pointsKey points

�� A history rich with innovationA history rich with innovation�� The pivotal role of the well logging technology in The pivotal role of the well logging technology in

the E&P processthe E&P process�� Main components of the well logging techniqueMain components of the well logging technique�� The workflowThe workflow�� Concerns about present interpretation process Concerns about present interpretation process �� Challenging environmentsChallenging environments�� A closer look to the futureA closer look to the future�� Key role of Knowledge Management in the future of Key role of Knowledge Management in the future of

the well logging techniquethe well logging technique�� ConclusionsConclusions

33 A history rich with innovation:A history rich with innovation:evolution of well logging technologyevolution of well logging technology

�� Since this first log, Since this first log, the technology evolved very rapidly the technology evolved very rapidly andand, thanks to sophisticated developments, , thanks to sophisticated developments, revolutionized the hydrocarbon Exploration and revolutionized the hydrocarbon Exploration and ProductionProduction industryindustry..

�� Well logging technology is now used in all the phases of Well logging technology is now used in all the phases of the E&P processthe E&P process from the drilling of the first wild cut well from the drilling of the first wild cut well in a field up to the abandonment of the last productive in a field up to the abandonment of the last productive level in the same field.level in the same field.

�� Due to the exploitation of a large number of physical Due to the exploitation of a large number of physical principles, principles, well logs can now measure a large number of well logs can now measure a large number of physical propertiesphysical properties of the geological formation (and the of the geological formation (and the sorroundingsorrounding environment) intersected by a well and both environment) intersected by a well and both in open and cased hole conditions.in open and cased hole conditions.

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Some early comments about the complexity Some early comments about the complexity of the technologyof the technology

““The methods of measurementsThe methods of measurements (and the parameters (and the parameters included) included) have now become so numeroushave now become so numerous that a log that a log analyst would need a analyst would need a specialized knowledge of specialized knowledge of physics, chemistry, geology, petroleum engineering, physics, chemistry, geology, petroleum engineering, electrical engineering, mathematics and many sub electrical engineering, mathematics and many sub branches of thesebranches of these, in order to follow developments , in order to follow developments in instrumentation,”in instrumentation,”

H. M. Johnson: A History of Well Logging, H. M. Johnson: A History of Well Logging, Geophysics, Vol. XXVII, N° 4, August Geophysics, Vol. XXVII, N° 4, August 19621962

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The pivotal role of the well logging technology The pivotal role of the well logging technology in the Exploration & Production processin the Exploration & Production process

�� Scope of log interpretationScope of log interpretation�� Well logging applications:Well logging applications:

�� Petrophysics;Petrophysics;�� Formation Evaluation;Formation Evaluation;�� Reservoir Characterization;Reservoir Characterization;�� Reservoir Management & Production Optimization;Reservoir Management & Production Optimization;�� Geology & Geomechanics;Geology & Geomechanics;�� Geosteering;Geosteering;�� Others.Others.

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Main components of the well logging techniqueMain components of the well logging technique

�� SensorsSensors�� (Digital) Data handling and interpretation models(Digital) Data handling and interpretation models�� Computer technologyComputer technology�� Education & TrainingEducation & Training

77 From past to present

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Sensor technology Data handling &interpretation models

Computer technologyEducation & Training

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Field tapes

PC techn.

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To achieve the challenging objectives of the well logging To achieve the challenging objectives of the well logging technology and since the key issue is the efficient and technology and since the key issue is the efficient and effective use of all available techniques, aeffective use of all available techniques, a strong strong collaboration with major Service Providers is necessarycollaboration with major Service Providers is necessary..This collaboration need to be effective in all the steps of This collaboration need to be effective in all the steps of the Formation Evaluation process:the Formation Evaluation process:�� tool/sensors/techniques design tool/sensors/techniques design ((fit for purpose R&Dfit for purpose R&D));;�� planning;planning;�� acquisition and QC;acquisition and QC;�� postpost--processing;processing;�� interpretation;interpretation;�� integration.integration.

Well logging process workflowWell logging process workflow

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PlanningPlanning

�� Knowledge of the technologies Knowledge of the technologies �� Costumer educationCostumer education�� Efficient organization:Efficient organization:

�� prepre--job meetings, job meetings, �� planning tools and preplanning tools and pre--job modeling, job modeling, �� reference manuals, reference manuals, �� definition of contingency plansdefinition of contingency plans

�� Integrated WLL and LWD FE strategies Integrated WLL and LWD FE strategies �� Value of InformationValue of Information

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Acquisition & Quality ControlAcquisition & Quality Control

�� Effective use of standards and best practices for Effective use of standards and best practices for the acquisitionthe acquisition

�� Effective Quality ControlEffective Quality Control�� Availability and correct use of answer productsAvailability and correct use of answer products�� Correct and timely delivery of field dataCorrect and timely delivery of field data�� PostPost--job meetings and use of Quality & Efficiency job meetings and use of Quality & Efficiency

indicators aimed at Total Efficiency of the Services indicators aimed at Total Efficiency of the Services and Products. and Products.

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Post processingPost processing

Many of the new technology logging measurements Many of the new technology logging measurements require post processing of the raw data:require post processing of the raw data:�� ResistivityResistivity

�� 2D Modeling, dip corrections, high conductivity contrasts2D Modeling, dip corrections, high conductivity contrasts�� Triaxial Induction Measurement & Electrical AnisotropyTriaxial Induction Measurement & Electrical Anisotropy�� LWD in deviated/highly deviated wellsLWD in deviated/highly deviated wells

�� NMR postNMR post-- processingprocessing�� Image logs post processingImage logs post processing

�� Image processingImage processing�� Quantitative textural information/faciesQuantitative textural information/facies

�� AcousticAcoustic�� improved DT comp, DT shear & DT Stoneleyimproved DT comp, DT shear & DT Stoneley�� Stoneley Permeability, Shear Wave Anisotropy, fluid Stoneley Permeability, Shear Wave Anisotropy, fluid

substitution and 4 D seismic modelingsubstitution and 4 D seismic modeling

1212

Integration of laboratory and down hole data Integration of laboratory and down hole data

�� The petrophysical models used at the well scale must be The petrophysical models used at the well scale must be validated by actual rock measurements.validated by actual rock measurements.

�� There are still large uncertainties in the correct use of There are still large uncertainties in the correct use of the petrophysical models available in the well log the petrophysical models available in the well log interpretation process:interpretation process:��selection of petrophysical models and parameters;selection of petrophysical models and parameters;��clay and shale definitions and their utilization are still clay and shale definitions and their utilization are still blurred;blurred;

��use of effective or total porosity regimes; use of effective or total porosity regimes; ��saturation models;saturation models;��petrophysical cut offs.petrophysical cut offs.��othersothers

1313

Interpretation/IntegrationInterpretation/Integration

Integrated interpretation of well data can strongly reduce Integrated interpretation of well data can strongly reduce uncertainties in Formation Evaluation and in Reservoir uncertainties in Formation Evaluation and in Reservoir Characterization studies.Characterization studies.

Integration Integration is a combination and coordination of separate is a combination and coordination of separate and diverse elements or units into a more complex or and diverse elements or units into a more complex or harmonious whole. harmonious whole. Since it implies the creation of a more complete or Since it implies the creation of a more complete or harmonious whole, integration can therefore be considered harmonious whole, integration can therefore be considered as a process whereby as a process whereby extra valueextra value is produced.is produced.

(Integrated Reservoir Studies (Integrated Reservoir Studies –– Luca Cosentino Luca Cosentino –– Edition TECHNIP Edition TECHNIP -- IFP)IFP)

Extra valueExtra value gainedgained through integrationthrough integration can be expressedcan be expressedeither in more complex but verified geological models or either in more complex but verified geological models or as a higher reliability in a simplified but stable modelas a higher reliability in a simplified but stable model..

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Concerns about present interpretation processConcerns about present interpretation process

In spite of the very advanced techniques in use and the very In spite of the very advanced techniques in use and the very long history of the well logging technology, the lack of agreed long history of the well logging technology, the lack of agreed interpretation strategies in the industry is evident because of interpretation strategies in the industry is evident because of the important discrepancies in the interpretation process used the important discrepancies in the interpretation process used by the different actors (Oil Co., Service Co. and consultants). by the different actors (Oil Co., Service Co. and consultants). These difference are mainly related to following points:These difference are mainly related to following points:�� Planning and Quality Control procedures (and culture ...)Planning and Quality Control procedures (and culture ...)�� Interpretation models:Interpretation models:

�� CPI deterministic vs. inversion by minimizationCPI deterministic vs. inversion by minimization�� Lithological vs. mineralogical modelsLithological vs. mineralogical models

�� Petrophysical models:Petrophysical models:�� effective vs. total porosity regimeseffective vs. total porosity regimes�� Sw models for shaly sandsSw models for shaly sands�� tensor resistivity interpretation modelstensor resistivity interpretation models

�� Use of quantitative interpretation results:Use of quantitative interpretation results:�� Petrophysical cut offsPetrophysical cut offs

�� Incompleteness of present commercial interpretation systemsIncompleteness of present commercial interpretation systems

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Some statement about well log interpretationSome statement about well log interpretation

�� In spite of the very sophisticated level reached by In spite of the very sophisticated level reached by modern technologies, the quantitative interpretation of modern technologies, the quantitative interpretation of well logs is still well logs is still more an art than a sciencemore an art than a science and, and, unfortunately, there are unfortunately, there are too many artists aroundtoo many artists around in this in this industry ...industry ...

�� Models and strategies are often selected by tradition or Models and strategies are often selected by tradition or feelingfeeling and not based on sound geologicaland not based on sound geological--petrophysical knowledge.petrophysical knowledge.

�� Validation of the results is often based on subjective Validation of the results is often based on subjective approachesapproaches (i.e. deterministic) and not on more (i.e. deterministic) and not on more objective ones (inversion by minimization).objective ones (inversion by minimization).

�� The The resultsresults of the interpretation of the interpretation are not presented are not presented together with the associated uncertaintiestogether with the associated uncertainties arising from arising from measurements, models and procedures.measurements, models and procedures.

1616

Storage and retrieval of well logs Storage and retrieval of well logs and petrophysical dataand petrophysical data

In the last few years, data volumes are increasing dramatically In the last few years, data volumes are increasing dramatically in the industry and well logs play a very relevant role in this in the industry and well logs play a very relevant role in this increase.increase.�� StorageStorage

The Corporate Data Base is the operating company most valuable The Corporate Data Base is the operating company most valuable asset. asset. Integrated geologic, well and reservoir simulations will add Integrated geologic, well and reservoir simulations will add to the data explosion. Data storage of high quality data should to the data explosion. Data storage of high quality data should preserve its integrity and availability.preserve its integrity and availability.Old data need to be restored and reprocessed.Old data need to be restored and reprocessed.

�� RetrievalRetrievalCross vendor compatibility is required to ensure that data usersCross vendor compatibility is required to ensure that data usersare able to retrieve and utilize information efficiently. are able to retrieve and utilize information efficiently. Data Base standards should be enforced to allow easier Data Base standards should be enforced to allow easier exchanges among partners.exchanges among partners.

1717 Challenging environmentsChallenging environmentsfor well logging technologiesfor well logging technologies

�� Deep water projectsDeep water projects�� CarbonatesCarbonates�� Complex reservoirsComplex reservoirs

�� Thin bedded reservoirs (electrically anisotropic)Thin bedded reservoirs (electrically anisotropic)�� Tight reservoirsTight reservoirs�� Structurally complex reservoirsStructurally complex reservoirs

�� Unconventional reservoirsUnconventional reservoirs�� Gas from Coal Beds and HydratesGas from Coal Beds and Hydrates

�� Integrated management of large fieldsIntegrated management of large fields�� Pivotal role of Well Logging and Petrophysics Pivotal role of Well Logging and Petrophysics �� Management of large and heterogeneous datasetsManagement of large and heterogeneous datasets�� Improvement of surveillance methodsImprovement of surveillance methods

�� OthersOthers

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A closer look to the futureA closer look to the future

Components to be discussedComponents to be discussed�� SensorsSensors�� Data handling and Interpretation processesData handling and Interpretation processes�� Computer technologyComputer technology�� Organizational challengesOrganizational challenges

Techniques of interestTechniques of interest�� Open hole Logging While Drilling (LWD)Open hole Logging While Drilling (LWD)�� Open hole Wire Line Logging (WLL)Open hole Wire Line Logging (WLL)�� Cased Hole & Production LoggingCased Hole & Production Logging�� Auxiliary wire line measurements & techniquesAuxiliary wire line measurements & techniques

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A closer look to the future: A closer look to the future: sensorssensors�� Sensors and electronicSensors and electronic miniaturizationminiaturization will allow the will allow the

construction of very compact and rugged toolsconstruction of very compact and rugged tools�� Tool/sensorTool/sensor designdesign will be necessarily will be necessarily assisted by assisted by

modelingmodeling of the physics of complex formation scenariosof the physics of complex formation scenarios�� Extensive introduction of Extensive introduction of new method of data new method of data

conveyanceconveyance (wireless, permanent sensors, others)(wireless, permanent sensors, others)�� High Data Rate TelemetryHigh Data Rate Telemetry in While Drilling logging will in While Drilling logging will

allow effective Real Time interpretation and Geosteeringallow effective Real Time interpretation and Geosteering�� Deep measurementDeep measurement will allow to illuminate large reservoir will allow to illuminate large reservoir

volumes in the interwell region (EM & Seismic) volumes in the interwell region (EM & Seismic) �� Triaxial or azimuthal measurementTriaxial or azimuthal measurement will enable directional will enable directional

looking ahead and around capabilities for advanced looking ahead and around capabilities for advanced Geosteering and Reservoir Management.Geosteering and Reservoir Management.

�� Cross well EM and Seismic tomographyCross well EM and Seismic tomography will allow an high will allow an high resolution characterization of the interwell region in terms resolution characterization of the interwell region in terms of reservoir structure/geometry and lithology/fluid of reservoir structure/geometry and lithology/fluid distribution.distribution.

2121A closer look to the future: A closer look to the future:

data handling and interpretation processesdata handling and interpretation processes�� Modern information technology will allow the development Modern information technology will allow the development

of of novel novel geosciencegeoscience techniques based on Remote Real techniques based on Remote Real Time interpretation Time interpretation both in case of both in case of E&ProductionE&Production activities.activities.

�� IntegrationIntegration between between well loggingwell logging andand well datawell data with with geophysical (Seismic & EM) datageophysical (Seismic & EM) data to improve reservoir to improve reservoir monitoring and production optimization strategies.monitoring and production optimization strategies.

�� Improved management of the UncertaintiesImproved management of the Uncertainties aimed at the aimed at the characterization of measurement uncertainties and characterization of measurement uncertainties and resulting interpretation results for resulting interpretation results for more informed risk more informed risk analysis and assessment of the Value of the acquired analysis and assessment of the Value of the acquired InformationInformation..

�� Improved role of modeling and inversion techniquesImproved role of modeling and inversion techniques aimed aimed at a better understanding of tool responses in complex at a better understanding of tool responses in complex formations models and maximize the reduction of the formations models and maximize the reduction of the uncertainties in complex 3D geometries (horizontal, highly uncertainties in complex 3D geometries (horizontal, highly deviated wells, deviated wells, interwellinterwell region, etc.).region, etc.).

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A closer look to the future: A closer look to the future: computer technologycomputer technology

�� Easier and faster handling, exchange, processing and Easier and faster handling, exchange, processing and analysis of large volumes of data to improve modeling, analysis of large volumes of data to improve modeling, Real Time interpretation and integration (Shared Earth Real Time interpretation and integration (Shared Earth Model approach)Model approach)

�� 3D visualization of well log interpretation results aimed 3D visualization of well log interpretation results aimed at a better understanding of interwell distribution of at a better understanding of interwell distribution of petrophysical and structural reservoir properties.petrophysical and structural reservoir properties.

�� Improved measurement accuracy and data/service Improved measurement accuracy and data/service Quality Control.Quality Control.

�� Down Hole signal processing, preDown Hole signal processing, pre--interpretation and interpretation and quick look interpretation.quick look interpretation.

2323 A closer look to the future:A closer look to the future:Organizational challengesOrganizational challenges

Main organizational challenges, that must be addressed Main organizational challenges, that must be addressed with the same level of commitment as the technical with the same level of commitment as the technical aspects are:aspects are:�� use of an adequate operational environment use of an adequate operational environment

(technology selection by pre project planning, data (technology selection by pre project planning, data quality control, data transmission, value of information quality control, data transmission, value of information assessment, etc.); assessment, etc.);

�� adequate expertise and collaboration between adequate expertise and collaboration between operator and data providers;operator and data providers;

�� quality, “fitquality, “fit--forfor--purposepurpose--ness” and integration of the ness” and integration of the results of the interpretation results of the interpretation aimed at maximum aimed at maximum reduction and quantification of the uncertainties;reduction and quantification of the uncertainties;

�� Shared Earth Models/Data Bases to maximize Shared Earth Models/Data Bases to maximize integration and adequate Software Hardware integration and adequate Software Hardware environments.environments.

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The key role of Knowledge Management in The key role of Knowledge Management in the future of the well logging techniquesthe future of the well logging techniques

�� Knowledge Management is a term Knowledge Management is a term applied to any initiative involving applied to any initiative involving people, processes and technology that people, processes and technology that leverages the knowledge within an leverages the knowledge within an organization to achieve business organization to achieve business results.results.

�� Knowledge Management practice Knowledge Management practice requires vision and organizational requires vision and organizational communities aided by leadership.communities aided by leadership.

�� Key types of knowledge:Key types of knowledge:�� Cognitive knowledge Cognitive knowledge �� Know WhatKnow What�� Advanced Advanced skilskil �� Know HowKnow How�� System understanding System understanding �� Know WhyKnow Why�� Self motivation Self motivation �� Care whyCare why

�� Advantages of KM: Advantages of KM: DO MORE WITH LESS!DO MORE WITH LESS!

Do the work

Share Learn

Innovate

KM basic model

Processes & Technology

Human element

2525 Conclusions (1/2)Conclusions (1/2)

To overcome the challenges discussed in the lecture, the To overcome the challenges discussed in the lecture, the industry need to cope with some important conditions:industry need to cope with some important conditions:�� the wide knowledge necessary for the optimal use of well the wide knowledge necessary for the optimal use of well

logging data and for reduction and quantification of logging data and for reduction and quantification of Formation Evaluation and Reservoir Characterization Formation Evaluation and Reservoir Characterization uncertainties, uncertainties, makes team working and integration a makes team working and integration a common and critical organizational practicecommon and critical organizational practice;;

�� technology innovation and knowledge aretechnology innovation and knowledge are, obviously,, obviously,important components important components in improving reliability of the in improving reliability of the resultsresults butbut, since we are always dealing with industrial , since we are always dealing with industrial projects, projects, all the efforts need to be consistent with cost all the efforts need to be consistent with cost efficiency and economical constraintsefficiency and economical constraints;;

to be continued …

2626 Conclusions (2/2)Conclusions (2/2)�� relationships between Oil Companies, Data Providers relationships between Oil Companies, Data Providers

Consultants and Academia must become more efficient in Consultants and Academia must become more efficient in the numerous steps of the process:the numerous steps of the process:

�� defining industry agreed “fit for purpose” R&D strategiesdefining industry agreed “fit for purpose” R&D strategiesfor the development of new sensors & acquisition for the development of new sensors & acquisition technologiestechnologies;;

�� creation of industry agreed integrated interpretation creation of industry agreed integrated interpretation strategies and models strategies and models aimed at the reduction and aimed at the reduction and quantification of FE and RC uncertaintiesquantification of FE and RC uncertainties;;

�� improve existing data management/interpretation HW & improve existing data management/interpretation HW & SW environments SW environments to improve results and maximize data to improve results and maximize data usage;usage;

�� improving knowledge sharing, cross education and training improving knowledge sharing, cross education and training by by adopting effective/efficient Knowledge Management adopting effective/efficient Knowledge Management strategiesstrategies to to fuel innovationfuel innovation,, to to aid better and faster aid better and faster decision makingdecision making,, help the industryhelp the industry toto do more with fewer do more with fewer resources!!!resources!!!

Thank you very much for the attention!Thank you very much for the attention!