SPWLA Kuwait 2012/2013

    June 18, 2013



Presenter: Mr. Adly A. M. Helba

Geoscience Advisor


One of the main challenges in dealing with carbonate (limestone and dolostone) reservoirs is the evaluation of its porosity, permeability and the intimately related hydrocarbon reserve and production. This challenge originated from the enigmatic results given via evaluating poro-perm property using traditional porosity logs and core analysis, with measurements being often inconsistent with production. This is usually attributed to the heterogeneous nature of carbonate pore system; type, size and distribution that cannot be resolved by conventional logs with a low vertical resolution (1-2ft), and unrepresentative sampling of core plugs.  The evaluation challenge is further stressed by the elusive behavior of carbonate permeability, which is not only (as in clastic reservoirs) controlled by porosity volume, but also linked to other effective factors as: depositional fabric and texture, diagenetic alteration and eugenic karstification as well as tectonic/non-tectonic fracturing and crackling.  
Image-perm is an unconventional technique applying borehole resistivity imager capability in overcoming many of the above mentioned problems and derives continuous and azimuthal outputs of high resolution porosity with considerable borehole coverage. It can also integrate the derived, high resolution porosities with the depositionally and diagenetically controlled petrophysical rock fabrics in providing continuous output of permeability.
To apply this approach on a field scale and on uncored wells/reservoir intervals, the images of at least one or two key cored wells should be first calibrated with detailed mesoscopic core-facies and microfacies analyses as well as core-measured poro-perm results.

A systematic workflow of this approach is established, and applied on one of the heterogeneous carbonate reservoirs in the Middle East with predicted poro-perm results matched closely with the real core measurements. The secondary porosity index (SPI, derived from sonic logs and Neutron-Density), and microporosity curve (derived from NMR) can be integrated in this module to partition the derived porosity into high resolution porosity fractions (primary, secondary and micro-porosities).


Author's Biography:

Geoscience advisor in Halliburton Egypt since 2009.  B. Sc. in Geology from Cairo University in 1981, M.Sc. in Cretaceous carbonate sedimentology in 1987 and PH.D in Paleozoic clastics sedimentology in 1991 from Cairo University. Currently, I am leading geoscience team in analysis and geological interpretation of Resistivity Images in both single- and multiwell projects in Egypt, Libya, Algeria and Kuwait. Prior to joining  Halliburton, I was acting as staff member (assistant professor) in Geology Department in Cairo University, in addition to as a consultant in some Egyptian oil companies; Bapetco, Oil Search, Norec and Schlumberger. The dissertation work focuses on facies and sedimentological analysis and high resolution sequence stratigraphy of both clastic and carbonate reservoir rocks.


    June 4, 2013

Innovation in Water Saturation Determination for Horizontal Wells: A Case Study from Kuwait


Presenter: Mr. Ahmed Elsherif

LWD Petrophysics Domain Champion


The oil industry has been dealing with logging data based on a vertical hole basis for decades. Most Petrophysicists uses the deep resistivity measurement as Rt for saturation calculation. This is true in most cases unless we are crossing a bed boundary or we have a very deep mud filtrate invasion.
In a horizontal hole, several factors are affecting the formation resistivity measurements. One factor to mention here is the adjacent bed resistivity effect. The electromagnetic waves generated from the logging tools will be covering the adjacent bed and the reading will be highly affected. Moreover, when the well trajectory is cutting a bed boundary at a high angle, polarization horns are affecting the tool measurement and causing severe noise that masks the formation true resistivity.
Recently, several horizontal wells in North Kuwait were having the above mentioned issues and KOC requested Schlumberger to investigate that and come up with a solution. Several modeling techniques were used to recover the true formation resistivity in some wells. An alternative option was proposed to KOC based on using Logging While Drilling (LWD) for Sigma (S) measurement. S has been known for the oil industry for decades as a cased hole logging technique which is used for reservoir monitoring. Open hole S measurement using traditional Wireline tools had limited value due to mud filtrate invasion.
Recording S using LWD technology managed to overcome the invasion effects since the data is recorded few minutes after drilling. One main advantage of recording S in horizontal wells is the fact that it has a shallower depth of investigation thus will not be affected by adjacent bed resistivity and also will not be affected by polarization horn effects. Another advantage is that the recorded S can be used in the future as a base log for saturation monitoring thus eliminating ambiguity in future cased hole interpretation. 
The technique of recording S by LWD was used recently for one of the horizontal wells in North Kuwait. The results showed very good agreement between the resistivity based Sw and S based Sw. Moreover, comparisons between S while drilling and while pulling out of the hole was attempted (time lapse technique) in order to reveal any free water movement in the formation. This technique is only valid for oil base mud. The comparison has revealed that in zones of slightly higher Sw, the formation water is bound and will not be produced. Later, the production test results agreed with the petrophysical evaluation.
Finally, Sourceless density measurement was demonstrated to KOC during the same survey. It showed very good agreement with standard density measurement.


Author's Biography:

Joined Schlumberger in 1981 as Wireline field engineer, worked in several countries (Saudi / Qatar / Egypt / India). He was involved in field testing the first FMI in the Middle East in Egypt.
He had several positions with Schlumberger in New Technology and Interpretation development. He Joined Data & Consulting services in 2001 and worked in Kuwait, Egypt and Iraq. Later, he Worked as a Principal Instructor for NExT teaching open hole and cased hole logging and interpretation internally and for several clients (Aramco / ADCO / SonAngol)
Recently, he moved to Drilling and Measurements as Domain Champion for LWD Petrophysics for Kuwait / Iraq and Oman since 2012.


    May 19, 2013

Determination of Formation Saturations


Presenter: Mr. Ercan Ozer

General Manager, Middle East and Caspian


It is essential that reservoir formation saturations (OIL, WATER, GAS) are determined accurately for reservoir economics. Starting with the exploration stage saturations should be monitored carefully during the life of the reservoirs.
Initial water saturation is one of the critical values that determine the oil in place. Residual oil saturation that enhanced oil recovery plans are based on is another important value.
The initial fluid distribution is controlled by the capillary pressure forces and is rock and fluid specific. The distribution and magnitude can be altered during different phases of the reservoir development. This starts with drilling practices including coring, production mechanisms, down hole measurement, and laboratory analysis.
There are several ways of determining and monitoring saturations by integrated interpretation of data obtained from subsurface rock and fluid samples and down hole measurements. Log analysis including LWD, is an essential element of integrated reservoir evaluation provided transforms developed to predict the desired parameters are calibrated. The input parameters to these transforms can be obtained for the specific reservoir rock and fluid samples utilizing several laboratory techniques.
This presentation outlines the several methods to determine the formations saturations from laboratory perspective and their applications to improve formation saturations for effective reservoir evaluation.


Author's Biography:

Currently, Mr. Ozer is the  General Manager of Core Laboratories Int.B.V. to direct Middle East and Caspian regions.  This position is accountable for the overall business activities of laboratories located in different countries.  These laboratories primarily service Turkey, Saudi Arabia, Kuwait, Bahrain, Qatar, Oman, Yemen, UAE, Pakistan, Iraq, and Caspian (Central Asia) region.
Mr.Ozer is active member of SPE, SPWLA and SCA and participates in the activities of these societies as Reginal Director. He served the local SPE Abu Dhabi chapter as Chairman during 1994-1995 season.
Mr.Ozer gives Core Analysis Schools to the regional operators and technical presentation regularly. His technical expertise is in Core Analysis and its applications.


    April 30, 2013

General Logging Practices and their Implications in Ukraine, Technology Department, Kuwait Energy, Kuwait


Presenter: Dr. Penumatsa Raju

Chief Petrophysicist, Kuwait Energy


Kuwait Energy has license to explore gas & condensate in Bilouviski and Chornukhinska (B & C) fields in Dneiper-Donets Basin, Ukraine. The fields were discovered in 1957 & 1977 respectively. After a few years of production the fields were placed under ‘suspended fields’ category in 1986 by Ministry of Oil & Industry, USSR. Kuwait Energy acquired 100% rights of the fields in 2007 and is putting continuous effort to assess the potential of this field. The main uncertainties involved in the assessment are:  wells drilled more than three decades ago with unreliable condition, lack of information on cuttings, cores, formation pressure and fluid nature. The proved reservoirs are silica-clastic and situated at depth range of 3500-4500m with uncertainty on the reservoir characterization. Most wells have poor quality of cement behind casing. Gas production was done in facilitated regime which led to sharp drop in reservoir pressure and early water break through. Log data is of poor quality without any digital data available. The earlier log analysis was based on out dated techniques and using legacy charts, monograms, core data when available, information from nearby wells/fields and regional geology. The shallow sections of this field were not considered to have any potential and no attempt was made to evaluate them.


The presentation involves the log data acquisition methods in Ukraine and their implication on data quality and analysis of well log data. More logical analysis has been carried out considering the data quality issues which are used in the present geological model. Also some potential hydrocarbon zones are identified in shallower sections. The work has been done by Dr. Penumatsa Raju and Abdulwahab Sadeqi under the supervision of Surendra Mohan, Technical Director (Geology) .


Author's Biography:

Dr. Penumatsa Raju is associated with Oil & Gas industry for more than 30 years as Petrophysicist, having worked in India, Malaysia and Kuwait involving planning & quality control of log data acquisition and log analysis of open-hole, cased hole and production log data. He has a few technical papers to his credit and regularly teaches log analysis to post graduate students at Andhra University. He worked with ONGC during 1982-2005, RIL, India during 2006-2007, Samit enterprises, India during 2007-2010 and currently working as Chief Petrophysicist for Kuwait Energy since December, 2010. He got his M.Sc (Tech) and Ph. D degrees in Geophysics from Andhra University in 1977 and 1982 respectively.  Dr. Raju is a member of SPWLA, AEG and AHI



    April 16, 2013

Identifying and Allocating Commingled Oil Produced from Eagle Ford and Buda Reservoirs in Horizontal Wells Using Geochemical Fingerprinting Technology


Presenter: Mr. Daniel Boyde

Weatherford Laboratories Inc


“Production allocation” involves determining the amount of oil or gas produced from each of several zones in a single well.  This objective traditionally has been achieved using mechanical logging methods.  However, geochemical fingerprinting technology can be used to accurately (≈2% error) allocate commingled production from multiple pay zones at <5% of the cost of production logging. 

Geochemical fingerprinting relies on the principle that the composition of the oil in different reservoirs commonly is slightly different.  Therefore, when oils produced from discrete zones are commingled, subtle chemical differences can be used to assess the contribution of each pay zone to the production stream.  This technique, which uses high-resolution gas chromatography (GC) data obtained on each oil sample, also requires the availability of samples of “end-member” oils that contribute to the commingled production.  GC peak heights, which reflect the abundance of each compound, are used to allocate commingled production using linear algebra. 


We describe the first known application of geochemical fingerprinting technology to the Eagle Ford Formation. The study included 18 oil samples produced from wells completed in the Austin Chalk, the Eagle Ford Formation, or the Buda Formation in two fields in Frio County and La Salle County, South Texas.  The purpose of this study was to determine if some of the oil produced from horizontal wells drilled in the Eagle Ford Formation contains Buda oil (possibly because fractures induced in the Eagle Ford extend into the underlying Buda reservoir).  This objective required us to determine if:  (1) oil finger-printing can differentiate oils produced from Austin, Eagle Ford, and Buda reservoirs;  (2) the compositional differences can be used as natural tracers to evaluate vertical communication between Eagle Ford and Buda reservoirs; and (3) the amount (if any) of Buda oil in “Eagle Ford” oil produced in the wells. Our results prove that compositional differences do exist between Austin, Eagle Ford, and Buda oils (which are explained by a geological model of oil generation and expulsion by Eagle Ford source-rock beds).


Using a Buda end-member oil sample and an Eagle Ford end-member oil sample, we conclude that ≈11% of the oil produced from one horizontal well drilled in the Eagle Ford Formation actually was produced from the underlying Buda Formation.  Using the same end-member oil samples, we conclude that a different horizontal well produces oil only from the Eagle Ford reservoir in which that well was drilled.


Author's Biography:

Mr. Daniel Boyde After completion of his Degree in Industrial Geology, Daniel Boyde’s 13 year career in Petroleum Industry commenced as a fluid systems analyst in a PVT laboratory in the UK. His fluid sampling and analysis experience has taken him from the jungles of Venezuela, deep-water West Africa, The North Sea, Asia and to the deserts of the Middle East.

Daniel has conducted numerous phase behaviour studies on a wide variety of petroleum systems and has extensive experience in Fluid Thermodynamics ranging from Enhanced Recovery, Solubility Swelling Studies, Interfacial Tension and Core Flooding.

Daniel is currently the Middle East & North Africa Region Business Unit Manager at Weatherford Laboratories, responsible for 7 laboratory facilities in the region



    March 26, 2013

Geomechanics: An effective multi-disciplinary tool for natural integration of disciplines in upstream petroleum decisions


Presenter: Mr. Satya Perumalla

Geomechanics Team Leader (Middle East), Baker Hughes – GMI


Geomechanics is known to the industry as a separate science to address issues from exploration, drilling, completion and production. While geomechanics addresses exploratory well risk, wellbore stability, completion optimization and production enhancement in depleted fields, it is fact that a geomechanical model integrates data of diverse origin to estimate the mechanical response of formation to in-situ stresses. This mechanical response of formation will impact different disciplines in different ways. That said, the formation response is seen by various disciplines: Drilling engineers, Geoscientists, Completion/Production Engineers in different forms and also at different times. This presentation mainly talks about various decision making situations of our industry at which geomechanics can be used as an effective decision support tool. In addition, the presentation also covers decision challenges posed by data insufficiency and provides idealistic situation for reference.

Author's Biography:

Mr. Satya Perumalla is working in Oil & Gas Industry as a Drilling & Geology Consultant over 16+ years at different levels, supporting Geoscience and Well-Engineering interests of various operators in the Middle East, Africa and India. He worked with Schlumberger Geoservices, Shell and British Gas Group for 11 years and then joined Baker Hughes / GMI in Dubai since 2007. Satya worked on various consulting projects linking geomechanics to wellbore stability, pore-pressure prediction, reservoir geomechanics and unconventional reservoirs. He initiated building geomechanics team for Middle East operations. He is an author of SPE technical papers and also teaching Geomechanics courses. He received M.Sc (Applied Geology) degree from Indian Institute of Technology- Roorkee, India in 1994 and General Management Diploma from Indian Institute of Mangement- Ahmedabad, India in 2010. Mr.Perumalla is a member of AAPG, SPE, EAGE and SEG



    February 19, 2013

Improved Rock Characterization by Dual Energy CT Scanning: Applications in Various Worldwide Formations


Presenter: Mr. Ken D Kelsch

Presenter: Mr. Moustafa R. Dernaika ,Ingrain Inc. – Abu Dhabi


Rock (micro) properties that control pore geometry determine macroscopic properties of the porous medium. Establishing the relation between micro properties and macroscopic physical properties of a rock sample is an essential requirement in the understanding of fluid flow behaviour and saturation distribution in porous media and in the production of oil and gas from petroleum bearing reservoirs. If variations in rock types are ignored, laboratory measurements for predicting fluid flow may be misleading. Reservoir rock types (RRT) can be defined on the basis of combined petrophysical properties and geological description. However, in complex carbonate reservoirs it may not be straight forward to establish reservoir rock types due to reservoir heterogeneity, which complicates the task of reservoir description where reservoir properties tend to vary as a function of spatial locations both in vertical and areal directions. These rock property variations necessitate the establishment of accurate and detailed understanding of the geological heterogeneities and their impact on petrophysics and reservoir engineering.

In special core analysis programs it is critical that a robust sampling strategy is devised so that samples are selected to be representative of the reservoir and to capture the heterogeneity. Samples provide data that directly go into reservoir models, and hence failure to select representative samples may have major impact on reserves and production calculations. The selection of sampling locations in the core can be best commenced on full diameter cores by high definition dual energy X-ray CT scanning, sedimentological description and conventional core analysis.

  In this presentation the dual energy X-ray CT scanning is introduced with special applications in carbonate and shale formations. From the X-ray data, produced at two different energy levels, continuous whole core scans are calibrated to produce bulk density (BD) and effective atomic number (Zeff) at half-millimetre spacing along core length. The Zeff parameter is related to the Photo Electric Factor (PEF), commonly used in well bore logging. At this resolution, 1 foot of core scanning produces around 700 CT images. The images show important geological features including fractures, vugs, bedding planes, laminations, fossils, bioturbation etc. The high-resolution X-ray computed BD and Zeff values can be used to interpret porosity, mineralogy and organic content (in shale). It will be shown that dual energy data logs and imaging can provide effective early geological information about the core while it is still in the barrel. This information gives lithology log along the core length that can match detailed geological descriptions conventionally acquired on slabbed cores. Such high resolution images and numerical data help in the geological description of the core, and eventually lead to more robust and representative sample selection. The technique provides unique capability for ensuring that the number of drilled samples is representative to the cored lithofacies by statistically linking plugs to the full diameter core. This is an upscaling feature of the methodology which proved to be of great importance in carbonate and shale formations around the globe



During deposition of the Jurassic and Cretaceous reservoirs, such reservoirs realized minimal amount of structural tectonic deformation.  Today, these same reservoirs under current tectonic regimes are compartmentalized and detailed fault interpretation provides the conduit (migration) and trapping of hydrocarbons. 
The application and knowledge of regional tectonics is critical to the awareness of the structural complexities.  Technical application such as wrench tectonics is important in finding and drilling for additional hydrocarbons and such structures are realized within Partitioned/Divided Zone of the Kingdom of Saudi Arabia/Kuwait.


Author's Biography:

Mr. Moustafa R. Dernaika is the Manager of Ingrain Inc. - Abu Dhabi since 2010. Before he joined Ingrain he worked for Emirates Link ResLab LLC (Weatherford Laboratories) as the Regional SCAL Manager in Abu Dhabi.


Moustafa holds BS and MS degrees from the Middle East Technical University in Ankara, both in Chemical Engineering. He is currently continuing his PhD study in Petroleum Reservoir Engineering at the University of Stavanger in Norway.


Moustafa has 12 years’ experience in the oil industry and has authored and co-authored 19 technical papers on the variation of petrophysical properties and hysteresis with rock types and wettability. His current research areas include Digital Rock Physics and Dual Energy CT applications



    January 29, 2013

Structural and Stratigraphic Trapping of Hydrocarbons within Late Jurassic to Early Cretaceous Section as Observed from drilling and 2-D/3-D seismic in Partitioned/Divided Zone of the Kingdom of Saudi Arabia/Kuwait


Presenter: Mr. Ken D Kelsch

Head of Appraisal/Exploration, Wafra - JO, Chevron


Structural and stratigraphic traps in the Partitioned/Divided Zone (PZ) between the Kingdom of Saudi Arabia and Kuwait suggest minimal tectonics during carbonate build-ups within the Late Jurassic to Early Cretaceous. Today, these same reservoirs are structurally compartmentalized as determined from pressure data, wells and the incorporation of an array of 2D/3D seismic data.


The application and knowledge of regional tectonics indicates that left-lateral strike-slip faulting produced many transpressional structures within the Arabian Peninsula.  The transpressional faults form the traps and can be mapped using 2-D and 3-D seismic data. They are sub-vertical and trend NS to NNW with en-echelon faults trending NW-SE to SW-NE. In addition minor transtensional faults further provide a pathway for the migration of hydrocarbon.  This structural framework was affected by single to multiphase inversion with a late stage en-echelon “collapse graben” faults that compartmentalize the Late Jurassic to Early Cretaceous hydrocarbon reservoirs.


The application and knowledge of regional tectonics, left-lateral offset with a preponderance for transpressional features existing within the Arabian Peninsula as well as minor but observable transtensional structures are the traps and migration pathways of hydrocarbon. Late Jurassic to Early Cretaceous reservoirs drilled today, suggest the structural framework is indicative of single to multiphase inversion with a late stage en-echelon “collapse graben” faulting that compartmentalize and trap the hydrocarbons.   

  The application and knowledge of regional tectonics is critical to the awareness of the structural complexities.  Technical application such as wrench tectonics is important in finding and drilling for additional hydrocarbons and such structures are realized within Partitioned/Divided Zone of the Kingdom of Saudi Arabia/Kuwait



During deposition of the Jurassic and Cretaceous reservoirs, such reservoirs realized minimal amount of structural tectonic deformation.  Today, these same reservoirs under current tectonic regimes are compartmentalized and detailed fault interpretation provides the conduit (migration) and trapping of hydrocarbons. 
The application and knowledge of regional tectonics is critical to the awareness of the structural complexities.  Technical application such as wrench tectonics is important in finding and drilling for additional hydrocarbons and such structures are realized within Partitioned/Divided Zone of the Kingdom of Saudi Arabia/Kuwait.


Author's Biography:

Ken D Kelsch is the section Head of Appraisal/Exploration team of Wafra – JO since 2009, with over 24 yrs of experience in structural interpretation, drilling appraisal/exploration and complex horizontal wells.


He has M.S. a degree with Thesis titled “3D Tecto-Stratigraphic Development of Beta Field Southern California”.

  After his B.Sc from UCLA in 1988 he joined Chevron Oil Field Research Co La Habra California. In 1991 he joined the Exploration and Petroleum Technology team of Chevron in California. Since then he has worked in Sumatra, Nigeria, Gulf of Thailand operations of Chevron prior to joining the JO of Chevron in Kuwait.





    January 15, 2013

Geomechanics Applications to Drilling, Hydraulic Fracture Design, Completion Integrity and Reservoir Management


Presenter: Dr. Mohammed Ahmed Mohiuddin

Principal Geomechanics Engineer, Schlumberger


Geomechanical models require quantification of insitu stresses, pore pressure and rock properties. Carbonate and Tight gas reservoirs are usually heterogeneous in nature. Hence spatial and time dependent changes of geomechanical properties throughout the life of the field gain importance. Modeling the complex subsurface conditions and properties through the overburden and reservoir enables the subsequent geomechanics analyses, hydraulic fracture design and completion integrity.

The presentation will introduce geomechanics applied to drilling, hydraulic fracture design, Completion intengrity and Reservoir Management. This will help to understand drilling events, hydraulic fracture behavior, design optimum hydraulic fracture job and forecast the performance of the stimulated well. In addition, depletion, reservoir compaction, subsidence, fault re-activation and overburden movement as well as their effects/consequences on completion integrity will be described. Case studies on applications to drilling, hydraulic fracture design application and completion integrity will be presented and discussed.



Author's Biography:

Mohammed Ahmed Mohiuddin is a Principal Geomechanics Engineer working for Schlumberger in Saudi Arabia. He started his career as a drilling engineer in 1989. After completing his Ph. D. in Applied Mechanics in 1997, he worked as Geomechanics consultant in Petroleum Industry. His specialization is petroleum geomechanics applied to drilling, production, hydraulic fracturing and coupled geomechanics simulation. He has more than 15 years of industry experience. He is a member of SPE and has published 40 papers in refereed journals and conferences





    November 2012

Enhanced oil recovery using N2 and CO2 gas injection while promoting clean power generation


Presenter: Mr. Alessandro Gorla and Dr. Krish R. Krishnamurthy

The Linde Group - Clean Energy Middle East


This presentation will discuss nitrogen and carbon dioxide gas injection for enhanced oil recovery while promoting clean power generation. A case study of nitrogen for EOR and gas lift purposes in the Cantarell field in Mexico will be outlined. Nitrogen injection in the Cantarell field was started in June 2000 and has been successfully operating for more than 12 years. The complexity of the implementation as was foreseen during the project development phase starting in 1996 will be described. Impact on production rates, number of wells, pressure and projected RF will also be summarized as well as the extension of the experience to other fields in the area. While Cantarell is and will probably remain for some years in the future as the largest reference for this application, a number of operators have followed or are in the process o consider and implement the same. Use of nitrogen for EOR typically displace natural gas injection, thereby releasing it for power generation using a lower carbon footprint. For miscible EOR, CO2 remains a leading option but is typically limited by lack of CO2 sources or economics of CO2 availability. Recent technology developments supported by programs aimed at greenhouse gas emissions reduction are providing opportunities for developing lower cost CO2 capture at very large scale. Early experience and future plans involving oxyfuel and post-combustion capture technologies for CO2 capture will also be presented.


Author's Biography:

Mr. Alessandro Gorla :  Alessandro Gorla joined Linde in 2011 as Vice President of Clean Energy in Middle East. Prior to Linde Alessandro was 6 years with Nuovo Pignone GE Oil & Gas, latest as General Manager for Turbomachinery in Middle East, and another 6 years with Air Liquide, latest as Business Development Manager Large Industries in Italy. Alessandro, who holds a Chemical Engineering degree from Politecnico di Milano, Italy, started his career in R&D and consulting and received a number of awards as business developer (Sales award 2006, Management Award 2007, CEO Growth leader award 2009, CEO Turbomachinery Organic Growth Award 2010). 

Dr. Krish R. Krishnamurthy:  Dr. Krishnamurthy is the Head of Clean Energy Technology – North America and CCS. He has expertise in energy generation processes, carbon capture and storage, separation process development, industrial gases production and applications, cryogenic technology. He holds Ph.D. in Chemical Engineering from Clarkson University, Potsdam, New York and is a registered professional engineer in the State of New Jersey.





   October 2012

Practical Downhole Dielectric and Diffusion-Based NMR Workflow for Viscosity Measurement in a Viscous Shaly Sand Reservoir Using Laboratory Calibration: A Case Study from Kuwait


Presenter: Mr. Khalid Ahmed
Specialist Petrophysicist, Kuwait Oil Company




Successful production of a viscous oil resource depends on understanding its volume and viscosity. Downhole sampling and PVT analysis provide detailed fluid properties; however,
sampling in shallow, unconsolidated formations is challenging and whatever point data are acquired does not constitute a continuous reservoir fluid profile. Nuclear magnetic resonance (NMR) logging is a promising method for evaluating viscosity. Challenges include identifying the NMR signal of oil from the overlapping bound-water signal and appropriately correlating the NMR parameters and viscosity.


We applied an integrated workflow combining dielectric and NMR logs with laboratory measurements to accurately determine log-derived viscosity in two wells and also identify

movable oil in a shaly sand reservoir. The laboratory NMR study was performed on core and bulk-fluid samples. Oil samples were used to derive NMR viscosities by using different equations for appropriate correlation with rheological viscosity. To extract the NMR signal of oil in the core plugs, an exchange study was performed in which water was replaced with deuterium dioxide (D2O), which is completely invisible to NMR. For downhole application, the D2O exchange method is replaced with dielectric logging. The physics of the dielectric and NMR measurements result in similar depths of investigation, in the 1- to 4-in range. The

diffusion-based NMR and dielectric measurements at multiple radial depths directly identified movable oil. The dielectric measurement provided an accurate water volume that is used as a reference for NMR-based fluid characterization. The D2O exchange study and radial profile


helped to define the NMR signal of visible oil. The laboratory-tested correlation, combining the visible oil T2 and the missing oil signal was applied to derive continuous viscosity values. The results are consistent with downhole PVT samples over a wide viscosity range




Mr. Khalid Ahmed is currently working with KOC as a Specialist Petrophysicist in the Heavy Oil Group. He holds a M.Sc. degree in Physics. As a career in Petrophysics with over 3 decades of experience, Khalid joined KOC in 2002, after successfully serving ONGC, India’s National Oil Company, for 21 years. He started his career as a Field Engineer and then moved in to the role of Petrophysicist, working in both onshore and offshore- dealing with Clastics as well as Carbonates. He is working with KOC Heavy Oil Group since its inception in 2007. He has several conference and journal publications. He is an active member of SPE, SPWLA and AAPG.

The current presentation based on the “Practical Downhole Dielectric and Diffusion-Based NMR Workflow for Viscosity Measurement in a Viscous Shaly Sand Reservoir Using Laboratory Calibration: A Case Study from Kuwait”.  This was presented recently at the “2012 World Heavy Oil Congress (WHOC12)” at Aberdeen .