bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurements of Streaming Potential for Downhole Monitoring in Intelligent Wells
Authors: Jaafar M. Z. , Vinogradov J. , Jackson M. D. , Saunders J. H. , Pain C. C. 
Published: March 2009

Abstract
Downhole monitoring of streaming potential, using electrodes mounted on the outside of insulated casing, is a promising new technology for monitoring water encroachment towards an intelligent well. However, there are still significant uncertainties associated with the interpretation of the measurements, particularly concerning the streaming potential coupling coefficient. This is a key petrophysical property which dictates the magnitude of the streaming potential for a given fluid potential. The coupling coefficient can be measured experimentally, but previous studies have obtained data for sandstone cores saturated with relatively low salinity brine (less than seawater). Formation and injected brine in hydrocarbon reservoirs is typically more saline than this. Extrapolating data obtained at low salinity into the high salinity domain suggests that the coupling coefficient falls to zero at approximately seawater salinity. If this is the case, then streaming potential signals will be very small in most hydrocarbon reservoirs.
We present the first measured values of streaming potential coupling coefficient in sandstone cores saturated with brine at higher than seawater salinity. We find that the coupling coefficient is small, but still measureable, even when the brine salinity approaches the saturated concentration limit. Consistent results are obtained from two independent experimental setups, using specially designed electrodes and paired pumping experiments to eliminate spurious electrical potentials. We apply the new experimental data in a numerical model to predict the streaming potential signal which would be measured at a well during production. The results suggest that measured signals should be resolvable above background noise in most hydrocarbon reservoirs, and that water encroaching on a well could be monitored while it is several tens to hundreds of metres away.
Reducing Uncertainty and Costs in Drilling and Completion: Innovative Underreamer Verifies Wellbore Diameter in Real-Time
Authors: Rasheed Wajid , Zhou Shaohua , Jones David 
Published: March 2009

Abstract
Applications such as close tolerance casing design and expandable liners, often necessary for deepwater and subsalt well construction, require underreaming to ensure adequate reservoir diameters. However, underreaming generates uncertainty sometimes, particularly in hard formations. Instead of direct real-time verification, reliance is placed on indirect indicators such as increased standpipe pressure or drilling torque. The uncertainty as to whether the desired wellbore-diameter is actually delivered exists until a calliper is run. Subsequently, a correction run may still be needed, hence additional cost.
This paper explains a design process to solve these problems. An explanation of a novel technology illustrates how it verifies and detects variations in underreaming diameter in real-time. A telemetry system alerts the user if there is a significant difference between planned and actual diameters and prompts a check of operational parameters such as WOB, drilling fluid pump rates or RPM, if needed, repeat underreaming in the uncertain interval.
A comparative evaluation was made of the drilling dynamics of underreamers and the root cause analysis of NPT. For example, bit only RoPs are higher than underreaming RoPs and in a combination BHA the bit tends to out-drill the underreamer. Not only does the underreaming have limited cutter contact with the wellbore and limited hydraulics, BHA modelling shows these limitations are worsened by wall-side forces and bending moments which are concentrated at the underreamer.
The design process sought to improve traditional technology by considering RoP, improved underreaming BHA stability and generate a more balanced cutting action. CFD (Computational fluid dynamics) show how a novel configuration of nozzle distances and orientations improves cuttings evacuation and reduces particle residence times.
In conclusion, a drilling engineering risk table presents 20 underreaming applications and is used as a benchmark for a comparative evaluation of underreaming risk types.
The Challenges of Designing and Installing High Pressure Gas Pipelines Through Inshore, Shallow Waters in Bahrain
Authors: McGlone David 
Published: March 2009

Abstract
In 1996 BAPCO embarked on a project to expand the Khuff Gas Transmission and Distribution networks in Bahrain. The project was divided into four discrete segments, namely, Transmission, Distribution, Offshore and Downstream.
The paper and presentation will briefly describe the overall project and detail the challenges faced by BAPCO in the design and installation of the 3, 18" high pressure gas lines in the offshore segment.
The offshore segment links Wharf Valve Station (WVS) at Sitra to Hidd Metering Station (HMS) located some 6 km away on the east side of Bahrain on Muharraq island. This offshore section is comprised of approximately 2 km crossing the main shipping channel that provides access to the port of Mina Salman. The remaining 4 kms traversed shallow waters that, at low tide, were above the water line in some areas. One section actually crossed an offshore island that is used by migrating terns.
Challenges related to the protection of the environment during construction and subsequent operation will be detailed. Construction methods used and problems encountered, including steps taken to maintain access to Mina Salman port via the shipping channel, will be also be presented
Productivity Enhancement of Horizontal Heavy Oil Wells in the South of Oman
Authors: Zreik Bassam , Hattali Ahmed , Busaidi Khalfan , Bushara Mohamed , Tripathy Surendra 
Published: March 2009

Abstract
Petroleum Development Oman operates a large number of heavy oil fields in the south of Oman.
One of the fields is being developed with horizontal wells completed with sand exclusion screens and beam-pumps to produce the heavy crude oil to surface. Development drilling is in progress as per the field development plan requiring more than 10 wells to be drilled each year.
The integrated asset team carried out a post production evaluation of the 2007 newly drilled wells. The evaluation identified five underperforming wells requiring further examination to establish cause of performance impediment and to devise ways to remedy the problem.
The well performance modelling of the underperforming 2007 wells indicates very high skin values. This suggests the wells are severely damaged (e.g., reduced permeability) and/or only a fraction of the sand face is open to flow, suspect due to presence of mud filter cake. The high skin values are significantly impacting the gross fluid production consequently affecting net oil production from these wells.
A wellbore clean up and stimulation treatment was designed and well interventions scheduled to remove the suspected mud filter cake, consequently improving well productivities.
This paper reviews the production performance following wellbore clean up and stimulation of five underperforming wells. Covering well performance analysis, treatment design, execution methodology and post treatment results including the way forward to advance the current wellbore clean up process to deliver higher productivity wells in the upcoming 2009 and future drilling campaigns.
Radius of Investigation for Reserve Estimation from Pressure Transient Well Tests
Authors: Kuchuk Fikri J. 
Published: March 2009

Abstract
Although it is often used in pressure transient testing, radius of investigation still is an ambiguous concept, and there is no standard definition in the petroleum literature. Pressure diffusion corresponds to an instantaneous propagation of the pressure signal in the entire spatial domain when a flow-rate or pressure pulse is applied (beginning of a drawdown or injection) to the sandface of a well. However, the initial pressure propagation is not diffusive but it propagates like a wave with a finite speed. If we have a pressure gauge at a distance r in a formation, we will only start to detect a pressure change (drop or increase) after a few seconds or minutes even if we have a perfect pressure gauge with 0.0 psi resolution. After the initial propagation, pressure starts to diffuse or propagates as diffusion, and we start to observe pressure change at a given space and time above the pressure gauge resolution and natural background noise, which could be as high as 0.1 psi. One of the constant background noises is the effect of tidal forces.
In this work, we present new formulae for radius of investigation in radial-cylindrical reservoirs and a new technique for general systems. The new formulation takes into account the production rate from the system, formation thickness, and gauge resolution. It is shown that the conventional radius of investigation formula (rinv=0.029ktϕμct), see Earlougher (1977)) for radial-cylindrical systems yields very conservative estimates. Radius of investigation is fundamental for understanding the tested volume; i.e., how much reservoir volume is investigated for a given duration of a transient test? For exploration wells, the reservoir volume investigated is one of the main objectives of running drillstem (DST) or production tests. Therefore, how far pressure may diffuse (radius of investigation) during a transient test is very important for exploration pressure transient well testing.
Assessment of Uncertainty in Saturation Estimated from Archie's Equation
Authors: Zeybek Ayse Donmez , Onur Mustafa , Tureyen Omer Inanc , Ma S. Mark , Al-Shahri Ali M. , Kuchuk Fikri J. 
Published: March 2009

Abstract
Volumetric methods are used to estimate the hydrocarbons in place of a reservoir. They require petrophysical data including porosity φ and water saturation Sw which can not be directly measured but must be inferred from other measurements. For example, water saturation is conventionally obtained from the Archie's equation, which requires inputs of porosity, ø, cementation factor, m, tortuosity factor, a, saturation exponent, n, true reservoir resistivity, Rt, and resistivity of formation water, Rw. Uncertainties in these input values directly affect the accuracy of water saturation estimation.
In this paper, we investigate the propagation of uncertainties of these input parameters into Sw estimated by Archie's equation. Error propagation equations (based on a Taylor series expansion of Sw around the mean values of the input paramaters) are derived for uncertainty characterization. Two cases are considered for the relationship between the input parameters; correlated or completely independent. It is shown that correlation among the input parameters, which may be due to different rock facies, can increase or decrease uncertainty in Sw and hence, ignoring existing correlation among the input parameters may lead to incorrectly characterizing the uncertainty in Sw. In addition, the dimensionless sensitivities and relative uncertainties of the input parameters, derived from the error propagation equations, clearly identify which of the input parameters will dominate the total uncertainty in Sw computations. Monte Carlo methods were used to verify the developed error propagation equations. A comparative study shows that the error propagation method is a good first approximation for uncertainty analysis, especially if the resulting Sw distributions are normal. However, it is well known that Monte Carlo methods are more general as they provide rigorous sampling of the response function (Sw in our problem) by accounting for the nonlinearity existing between the response function and its input parameters, and thus should be used for accurately quantifying the uncertainty.
Successful Application of Extra-Long Expandable Cased-Hole Liner Remediates Production Well
Authors: Al-Barghawi Riyadh , Looni Qadir , Sanders Tom , Saad Marc Antoine , Stephenson David 
Published: March 2009

Abstract
Corrosion in the production liner of a prolific oil production well offshore Saudi Arabia has compromised the well integrity and created several significant leaks, resulting in excessive water encroachment into the produced fluids. The approximately 2,000ft section of the affected casing was across the formation containing the Umm Er-Radhuma water aquifer. Previous attempts to remedy this situation using cement squeezes were unsuccessful.
Installation of approximately 2,175ft of 5-1/2in. × 7in. expandable Cased-Hole Liner to remediate the leaking and corroded 7″ casing was successfully performed and tested. The one-trip installation proved the expandable technology in terms of its operational reliability, significant installation length, flexibility to line a combination of two different 7″ casing weights across the same setting zone, ability to apply isolation joints at selected locations and setting at a shallow depth of 718ft in this application.
The results and methodology of the operation during the installing and expanding of the cased-hole liner are further discussed to demonstrate the advances in the development of expandable technology and associated tools for such long and continuous installations. Details of the successful application are used to provide quantitave results of critical parameters that impose challenges and limitations on solid expandable technology. The installed configuration with a post expanded length of 2,081ft, which was pressure tested to 1,000psi; has proven to be the most appropriate solution for the remediation of this type of well challenge.
Numerical Modeling of Multiple Hydraulically Fractured Horizontal Wells (MHFHW)
Authors: Soleimani Arash , Lee Byung , Ghuwaidi Yahya , Dyer Steve 
Published: March 2009

Abstract
Horizontal wells with multiple fractures are becoming more prevalent in the Industry. They are especially beneficial in carbonate plays where acid and fracture stimulation can be used to improve productivity, the technique can be used for tight reservoirs and multiple compartments or anisotropic reservoirs with high permeability contrasts. Reliable evaluations of stimulation performance are required for field development planning. As such, pressure transients are often used, and can be successful, tight reservoirs where transient flow regimes can be used to observe and define the various impacting factors of stimulation, such as fracture length, conductivity, orientation, etc.
This project investigates the modeling and interpretation of pressure transient responses of multiple hydraulic fractured horizontal wells (MHFHW) using a numerical reservoir model. After validating the numerical model using an analytical solution applied to a simpler reservoir/well model, complex reservoirs are simulated and pressure transient response signatures obtained. Sensitivities of key reservoir/well/fracture properties are investigated and a result of each case is presented. Finally, an actual case where seven transversal fractures of a long horizontal well is modeled using a sector of the full field reservoir simulation model (geological/structural), where the results are interpreted and discussed. Fracture characteristics have been approximately estimated by comparing real well test pressure buildup analysis from field and simulation results.
Constraining Interwell Water Flood Imaging with Geology and Petrophysics: An Example from the Middle East
Authors: Al Ali Malalla , Vahrenkamp Volker , Elsembawy Saber , Bhatti Zahid , Reeder Stacy Lynn , Clerc Nicolas , Wilt Michael 
Published: March 2009

Abstract
Time-lapse cross-well electromagnetic (EM) surveys are used to monitor two types of fluid injection (Water Injection and Water Alternating Gas) in a giant field in the Middle East. Cross-well EM data will help optimize sweep efficiency, identify bypassed pay, and predict fluid-related issues such as water breakthrough by providing an image of the resistivity distribution between boreholes in time lapse. This paper explores the influence of a high quality background geologic model in constraining the interwell results and providing a higher resolution image of the ongoing flooding processes.
The classic EM inversion process determines a coarse (3 to 5 m resolution) resistivity distribution from a basic initial static reservoir model built from logs. This study refines the model by adding variable resolutions to encompass the small-scale heterogeneities common to carbonate reservoirs. Incorporating geological data derived from seismic attributes, core descriptions, and detailed log analyses into the static model helps optimize the EM inversion and increases the resolution of the resulting inverted model.
Increasing Production from a Shallow, Underdeveloped Reservoir in the Bahrain Field with Combination of Reservoir Analysis and Geochemistry
Authors: Abdulla Nayera Karim , Nedham Najla , Murty C. R. K. , Al Ansari Yahya 
Published: March 2009

Abstract
Ever since the Bahrain field was discovered in 1932, the main focus of effort was on major formations of the field, leaving shallow formations not fully exploited. Today with the increase in oil price and the depletion of major formations, there is a greater preparedness to consider increasing production from these under developed zones.
This case study was initiated with the purpose of increasing production from the Magwa zone, which is the most economically attractive of the shallow zones. The zone is the basal member of the Rumaila formation of the middle Cretaceous Wasia group. It is predominantly limestone with interbeded shale.
This case study shows an integrated methodology to enable a better understanding of the reservoir production behavior and to explain the lateral heterogeneity of the formation. This investigation was triggered by the variation in the formation water salinity from North to South. Water saturation maps, production history, geochemistry and structure set-up were used as the main input in this analysis. The interpreted relations and trends between these factors were used to explain the behavior of the reservoir. The outcome of such investigations is of critical value in determining the location of new development wells, selecting candidate wells for workover and for EOR processes.
This paper will explain how a better understanding of the reservoir through data integration has resulted in a significant increase in oil production.
Thermal EOR Pilot Plan for a Shallow Limestone Reservoir (Rubble Zone) in Bahrain Field
Authors: Murty Challa R. K. , Kumar K. , Galard Jean-Hector de , Mazeraud Virginie 
Published: March 2009

Abstract
Bahrain field, the first hydrocarbon discovery in the Arabian Gulf, is a multi-stacked elongated anticline structure with a stack up of 16 Oil & 4 Gas Reservoirs.
"Rubble Limestone" is the descriptive name given to a massive Limestone unit of the Mishrif formation, in middle Cretaceous in age. The zone consists of two layers, namely Upper Rubble and Lower Rubble. Both the layers are eroded in the crestal part of the structure. Large volumes of oil are trapped against the Blue shale at the up structure pinch outs of upper & lower Rubble. Fault cuts are observed in more wells indicating intense faulting and fractures.. The zone has both heavy & light oil. The amount of Heavy oil is estimated to be 90% of the initial oil in place. Currently only light oil is being produced. This paper highlights the studies to evaluate Heavy oil production potential.
Two separate studies were carried out, the first was to describe and characterize Rubble in order to map the light & heavy oil and the water bearing layers. Geo statistical methods were used to populate the 3D model of the reservoir with porosity & permeability values.
A detailed analysis of the logs indicated that light oil is associated with large separation between deep & shallow resistivity. It was observed that whenever there was heavy oil, the separation between the resistivity curves was either very less or even negative. Three rock types were identified and the habitat of light, heavy oil and water was accordingly assigned.
After obtaining an estimate of the areas of heavy and light oil, a fresh study was initiated to review and evaluate the Heavy oil prospect and to prepare a suitable thermal EOR pilot plan for the heavy oil recovery using Fraca® and PumaFlow® softwares. The study included (a) a review of the Reservoir description done earlier, (b) numerical modeling and simulation of a pilot area, (c) find out the suitable EOR process and design the pilot.
The study indicated that the reservoir has too low matrix permeability and very small fracture volumes to allow steam chamber formation. SAGD mechanism was therefore found not efficient for this reservoir. Huff and Puff has been simulated using two wells in the pilot area and found attractive. Cold production from six different Horizontal wells were simulated and tested. They indicated that cold production followed by Huff and Puff will be efficient to recover the Heavy oil.
The paper will describe the results of the study which led to drilling of the Horizontal pilot well for Cold production to be followed by Huff and Puff Thermal process.
Air Injection Potential in Kenmore Oilfield in Eromanga Basin, Australia: A Screening Study through Thermogravimetric and Calorimetric Analyses
Authors: Sarma Hemanta , Das Shyamol 
Published: March 2009

Abstract
Although air injection process has been a proven low-cost EOR technique for tight high-temperature light-oil reservoirs elsewhere, there has not been any Australian field application even though several reservoirs appear to meet the screening criteria for the process. Moreover, air injection could be a more attractive alternative for reservoirs that are amenable to hydrocarbon gas processes, thus freeing "cleaner and greener" gases for use for energy resource. Moreover, unlike most EOR processes, the air injection process does not require water, a scarce natural resource in Australia.
In this screening stud, y Kenmore oilfield in Eromanga Basin operated by Beach Petroleum has been chosen as the candidate oil. Kenmore reservoir is a 1395-m deep tight (4.4mD) light-oil (48.7°API) reservoir at 92°C. As the process feasibility depends primarily on the oxidation characteristics of the oil and its ability to sustain the ignition front during the process, the first step undertaken is the thermogravimetric and calorimetric characterization of Kenmore oil to (i) identify the temperature range over which the oil reacts with oxygen, (ii) examine the oxidation behavior within the temperature range identified, and (iii) evaluate the mass loss characteristics during the oxidation.
A series of thermogravimetric analysis (TGA) and pressurized differential scanning calorimetric (DSC) tests were conducted on Kenmore oil. Tests showed two distinct exothermic reactivity regions of temperatures within 200-340°C and 360-450°C, with an 85-95% mass loss when the temperature reached 450°C. Endothermic reactions are attributed to evaporation, distillation, and thermolysis; whereas exothermic reactions are due to low temperature oxidation, pyrolysis, and high temperature oxidation. It was observed that at an elevated pressure resulted in accelerated the bond scission reactions, a positive sign as far as the application of the air injection process is concerned; for, it suggests that Kenmore oil has the oxidation potential under high pressure air injection.