bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimating Cementation Factor (m) for Carbonates Using Borehole Images and Logs
Authors: Akbar Mahmood , Steckhan Jan , Tamimi Masoume , Zhang Tianhua , Saner Salih 
Published: June 2009

Abstract
Carbonate reservoirs account for 60% of today's hydrocarbon production. Several giant carbonate fields in the Middle East are expected to be the dominant source of hydrocarbon production through the current century. Therefore, understanding carbonate reservoirs and producing them efficiently have become industry priorities and are likely to remain so.
In order to assess a possible hydrocarbon reservoir, hydrocarbon saturation needs to be determined with good accuracy. In 1942 Archie published a formula to estimate water saturation in reservoirs. In case of carbonates, the saturations computed by the formula are not always correct. The factors complicating the role of the formula are known as Archie Exponents, namely, porosity exponent (m, also known as cementation factor) and saturation exponent (n). Both exponents tend to vary quite often in the carbonate reservoirs. With the exception of cores, no reliable and well established techniques exist today that can give a good estimate of these exponents.
Estimating cementation exponent (m, porosity exponent) from the well logs is the main objective of this paper. The technique addressed in it is based on the assumption that the amount and pattern of cementation, caused by diagenesis, in carbonates is one of the factors controlling the value of m. Therefore in order to estimate it for carbonates, the cementation in them should be quantified. It was achieved through integration of electrical borehole images and petrophysical logs with the cores. The data on cementation was then used to estimate ‘m’ as a continuous curve for carbonate reservoirs.
The technique provides a unique way, which incorporates textural part of carbonates, to estimate cementation factor (m) for carbonates. It has been applied to carbonates of the Middle East and Europe with good results, which were verified by the core data and production results.
Normalized and De-Normalized PVT Methodology for Black Oil Simulation
Authors: Dabbour Youssef , Sener Ilhan , Al Marzouqi Mohamed 
Published: June 2009

Abstract
The procedure presented in this paper offers a way to combine and integrate black-oil PVT data obtained from several wells at various depths in a consistent and easy manner, especially when the PVT properties exhibit variation with depth and an EOS model is not readily available. In principle, it is similar to normalizing and de-normalizing SCAL data.
Although the method was primarily intended to honor and consistently take into account vertical variation of black oil PVT properties, it can also be used to reliably estimate oil PVT properties at elevations close to the GOC where reliable fluid sampling may not be possible due to gas coning or cusping during sampling operation.
The following are the main benefits of the method: Detecting and representing vertical variation of fluid properties in a reservoir or compartment especially when access to an EOS package is not readily availableVerifying reservoir compartmentalization by identifying lateral variations in PVT propertiesValidating PVT parameters and their variations with depthGiven sample PVT data from various depths, generating representative black oil PVT tables at any required depth for use in black oil simulation
A Modeling Feasibility Study Indicates Seismic AVO has Potential to Discriminate between Brine and Hydrocarbon in Middle East Carbonate Reservoir
Authors: Mahmoud Sabry L. , Othman Adel A. , Soroka William L. , Romero Tony , Smith Adrian 
Published: June 2009

Abstract
A seismic Amplitude Variation with Offset (AVO) feasibility study was successfully conducted to investigate the potential for fluid discrimination in a high porosity carbonate reservoir from a producing oil field in the Middle East. Gassmann fluid substitution was used to model the available well log data, which included compressional and shear sonic logs and density logs to produce synthetic well logs representing the reservoir at 100% fluid saturations of brine, oil and gas at reservoir pressure and temperature conditions. The modeled brine, oil and gas logs were used to calculate the AVO responses at the top and base of the reservoir layer using the Zoeppritz equations. The responses for all three fluids were found to be a Class-4 type AVO. The AVO results on the synthetic CDP gathers suggests that brine can be discriminated from hydrocarbon. These encouraging AVO results on synthetic data suggest that with good quality seismic data it might be possible to see a difference in AVO response between brine and hydrocarbon filled porous reservoir. An AVO case study was performed using available relative amplitude CMP gathers along a 2D seismic line extracted from a 3D seismic volume. The effects of key reservoir properties on AVO response were examined to help establish interpretation guidelines and better understand the potential for misinterpretation.
Direct Strength Measurements of Shale Interaction with Drilling Fluids
Authors: Hemphill Terry , Abousleiman Younane , Tran Minh , Hoang Son , Nguyen Vinh 
Published: June 2009

Abstract
Athough a crucial factor in drilling, the effects of the interaction between drilling fluids and shales on rock strength have not been directly studied in a laboratory setting. Instead, indirect methods, such as monitoring of shale swelling behavior, penetrometer tests, shale dispersion tests, etc., have commonly been used to gauge "relative" shale strength. In the results presented here, fluid interaction with two very different shales is reported and interpreted. One shale, from deepwater offshore West Africa, was tested with invert emulsion fluids (IEF) having varying water phase salinities. The second shale, taken from land drilling in Oklahoma, was tested with IEF and brine-based drilling fluids. The shale strengths were directly measured as functions of fluid chemistry and exposure volume using a specially-designed testing device located at the Poromechanics Institute (PMI) of the University of Oklahoma.
IEF having differing water phase salinity levels (ranging from 50,000 to 350,000 ppm calcium chloride) were first tested to determine changes in rock strength with exposure volume. Rock cohesive strengths and internal friction angles were then calculated, and the results showed changes in rock strength as a function of water phase salinity and exposure time. Additionally, the Oklahoma shale samples were exposed to calcium chloride brines having the same salinity levels (50,000 and 350,000 ppm) as the IEF, and the resulting effects on rock strength as a function of fluid chemistry and time were measured and compared to the IEF results.
The results clearly show that drilling fluid chemistry and exposure time have direct bearing on shale strength. This study should be interpreted as only the beginning of study of fluid interaction with shale: there is much to be learned here, yet much more in the future.
Estimation of Interwell Connectivity in the Case of Fluctuating Bottomhole Pressures
Authors: Kaviani Danial , Jensen Jerry L. , Lake Larry W. , Fahes Mashhad 
Published: June 2009

AbstractInjection and production rates are often the most readily available data in a waterflood. Yousef and coworkers have shown that these data can be analyzed using a capacitance model (CM) to determine interwell connectivity and provide a tool for waterflood management. Although the existing CM performs well when tested with data from a reservoir simulator and in some field cases, it is less reliable in cases where bottomhole pressures (BHPs) are changing but not measured and/or where producers have been shut in for extended periods. This paper presents two new important developments of the CM to address these shortcomings: the segmented CM and the compensated CM.The segmented CM can be used where BHP data are unknown. The compensated CM overcomes the problem of the requirement to rerun the model after adding a new producer or shutting-in an existing producer. If both BHP changes and shut-in periods occur, both the segmented and compensated CMs can be used simultaneously to construct a single model for a longer period of data.In several simulated cases with fluctuating BHPs, the segmented and compensated CM successfully determined the true interwell coefficients. The conventional CM gives up to 70% error. In a field case, the segmented and compensated CM improved the prediction R2 by 15% compared to the existing CM. In this field example, there is good agreement between seismic impedance and results from the combination of the segmented and compensated CMs.The existing CM, which is a good beginning, requires enhancements to be more versatile. The segmented and compensated CMs will make connectivity estimation more robust because pressure data are often unavailable or human interventions (e.g., work-overs) cause the flow rates to vary. Adapting the CM to tolerate BHP changes and shut-in wells, as we have done, provides this versatility.
Safe Behaviour as a Function of Consequences – B:f(C)
Authors: Tucker John 
Published: June 2009

Abstract
When seeking to achieve excellence in HS&E performance it is crucial to understand the nature of human behaviour and what drives our behavioural choices. There are many influences over behaviour but none quite as significant as our expectation of what the consequences of our actions will be for us as individuals and our teams.
Behaviour is mainly a function of such consequences (B:f(C)) and understanding this means that we are able to significantly influence people's choice of behavior when it comes to risk taking. HS&E excellence in high performing safety cultures requires a thorough appreciation of this simple fact in order to sustain continuous improvement and provide the opportunity for zero accidents.
It is possible in fact to achieve 100% safety critical behaviours that become habitual practices in relatively short time periods. However this can only be achieved and sustained if we truly understand the consequence drivers for individual and group behaviours and how to use these to the advantage of HS&E performance. It is also essential to embrace all parties in this process so that contractors import safe behavioural practices into client organisations and this requires careful consideration at the contract negotiation stage.
It is possible through effective consequence and therefore behaviour management strategies to achieve zero accidents in any operational environment.
Successful Application of Swell Packer Technology to Shut-off Water Production in Horizontal Wells – Case Studies from Onshore Abu Dhabi
Authors: Aboukshem Ali A. , Al Katheeri Abdulla B. , Kenawy Maher M. 
Published: June 2009

Abstract
The subject field has been on production for more than 35 years from multi-layered heterogeneous carbonate reservoirs. Due to the field's maturity, the water cut has started increasing gradually in some producers and, consequently, production from these wells has been affected awaiting implementation of artificial lift. To deal with the water production and prolong the natural flowing life of the wells, various water shut-off techniques available in the industry were evaluated in order to select the most suitable one that could be deployed in open-hole sections of horizontal wells.
This paper presents two case studies where a mechanical water shut-off technique, involving swell packers, was successfully applied in horizontal open-hole sections. The systematic approach adopted by the operator to build the business case, select the candidates, acquire the PLT data, execute the jobs, evaluate the performance of the water shut-off jobs and future plans are presented in this paper. The paper also addresses the conceptual application of borehole segmentation with swell packers to improve well performance.
Remediation of Hazardous Materials with an Emphasis on NORM
Authors: Sharkey Megan A. , Burton James M. 
Published: June 2009

Abstract
Everyday, Naturally Occurring Radioactive Material (NORM) is produced and is a hazard for the oilfield industry. The oilfield industry releases NORM from the sub-surface to the surface during the production processes that produces water, oil and gas. Most often NORM is found in production tubing, piping, and equipment, such as tanks or heater treaters that can build up scale or store fluids. Leakage or a simple work-over can get this on the ground or on a workers clothing. If the NORM solid is inhaled or enters a human body orally, it can cause the worst type of cancer.
There are multiple ways to handle NORM waste efficiently, safely, environmentally, and cost efficiently. Handling of NORM begins during the remediation of a well or site equipment, then the waste should be minimized and securely contained and, lastly, responsibly disposed. Removal of the scale or sludge from pipe may be done using either a "Pipe cleaning Machine" or inside a "decontamination booth". Each uses high pressure water blasting for removal of NORM and collecting the sub sequential waste in different catch systems. Waste collected may be minimized by separating out the wash water then chemically and mechanically fluidizing the NORM using a "No Moving Parts Grinder", "Sand Wash Unit", or a Gasification unit. Minimized or non-minimized wastes have multiple disposal options including land-farm (dilution), down-hole disposal, and encapsulation in an impermeable cell. A recent technology referred to as gasification minimizes, disposes, and produces energy in the same system. Disposal methods vary in safety and distance from public. Further, remediation, minimization, and disposal options drastically vary in cost efficiency and long term safety.
Importance of Mercury Injectiion Capillary Pressure (MICP) Measurements at Pseudo Reservoir Conditions
Authors: Mitchell Phil , Al-Hosani Ismail , Mehairi Yousuf Al , Kalam Mohammed Zubair 
Published: June 2009

Abstract
Laboratory Special Core Analysis (SCAL) tests are designed to mimic measurements on representative reservoir cores at representative test conditions. These ‘rescon’ tests are however difficult to conduct, and generally cause many uncertainties in test design and numerous experimental artifacts for acceptable interpretations. Success has been achieved primarily in water-oil rescon displacements with live crude at full rescon and in gas process displacements (secondary gas injection, tertiary gas injection and WAG/SWAG). Capillary pressure (Pc) measurements form the basis of SCAL evaluation, and hence the importance of deriving Pc data as accurately as possible from different types of tests.
High pressure mercury injection tests were performed on selected rock types from a prolific carbonate reservoir, and results compared with that typically done at the ambient pressure conditions. Reservoir core samples from same depths were also investigated using multi-speed centrifuge at a high temperature and reservoir net confining stress. Additional core characterization data were obtained using NMR T2 relaxation times at stressed experimental conditions.
Primary drainage Pc and pore throat distribution data derived from mercury injection showed differences for tests at ambient conditions when compared with stressed conditions. The detailed study involving several rock types showed differences in entry pressures and the distribution of pore throat sizes, with the latter showing much narrower and prominent peaks at stressed conditions. These results were compared with centrifuge measurements on reservoir core plugs from similar depths at the same stresses, and confirmed the trends observed. Variations in MICP and centrifuge based Pc is explicable from different underlying principles in the techniques.
The Pc data at pseudo reservoir conditions enhances the confidence in validating the reservoir rock types and the ensuing static model development. Reservoir core measurements at representative test conditions underlie the model development to assess STOOIP and subsequent recovery schemes.
The Development of an Integrated Prioritization and Tracking System to Insure the Integrity of Safety Critical Systems
Authors: Cooke Steven , El Dine Ahmed Ezz 
Published: June 2009

ABSTRACT
A key tenet of Integrity Management is the appropriate focus on critical equipment systems. Many of the lapses in system integrity are the result of improper allocation of resources to less critical areas. A system to clearly identify and communicate criticality as a decision-making criterion regardless of the specific application (operations, inspection, or maintenance) is needed to assure that the ‘right thing is done at the right time’.
ADGAS has developed a HSE Critical Equipment System (HSE-CES) in collaboration with a consultant that links equipment designations that are ranked as critical from the HSE point of view, to inspection and maintenance routines and affected equipment systems. This system is designed to maintain the integrity of critical systems. KPI's are developed to provide both leading and lagging indicators for the effectiveness of this system. The key innovations are the identification of equipment individually instead of as overall systems, and the common interface to operations, inspection and maintenance functions. This allows better coordination of integrity maintenance efforts and an early warning for areas requiring more immediate attention. Components are linked to the larger systems that they protect to provide a better evaluation of the overall integrity risk rather than simply a component failure risk.
Steam Injection into Fractured Carbonates – The Physical Recovery Mechanisms Analyzed and Upscaled
Authors: Bychkov Andrey , Verlaan Marco , Boerrigter Paul , van Heel Rijswijk Ton , van Dorp Johan 
Published: June 2009

Abstract
Conventional displacement methods such as waterflooding do not work effectively in densely fractured reservoirs. The high fracture permeability prevents significant pressure differentials across oil bearing matrix blocks leading to negligible oil drive. In such reservoirs one has to rely on natural mechanisms like capillary imbibition or gravity to recover oil from the matrix rock. In Middle East fractured carbonates, the matrix rock is commonly oil-wet or mixed wet and only gravity drainage remains a feasible process. However, permeabilities are usually low, &lt;10 mD, resulting in low gravity drainage production rates with high remaining oil saturation and/or capillary holdup.
Thermal EOR methods have the potential to improve the gas oil gravity drainage (GOGD) rate and ultimate recovery. For shallow fractured reservoirs, it is feasible to inject steam into the fracture system, in the process known as Thermally Assisted GOGD (TAGOGD). Steam will condense as it contacts cooler matrix rock, resulting in a steam front that develops in a stable way through the fractures. Conductive heating of the matrix will result in oil expansion, viscosity reduction, solution gas drive and stripping effects. No viscous pressures are building up, and steam drive does not occur. For reservoirs containing viscous oil, the viscosity reduction effects are most important. When steam is injected in light oil reservoirs, solution gas drive and stripping effects potentially become dominant.
In this paper we analyse the effect of the different recovery mechanisms. We discuss the results of stack simulations for light oils and for a range of fracture spacings with reference to our previous results on viscous oils. We compare single-porosity simulations of a fracture-matrix stack system with dual-permeability simulations. The dual-permeability modeling requires special techniques to capture transient effects.
Recent Innovations and the Importance of Planned Maintenance & Inspection Procedures
Authors: Warriner Duncan 
Published: June 2009

ABSTRACT
The considerations made during the design phase of a pig trap can be vitally important in ensuring that the operational unit is both practical and safe to use. Primarily we explore what we actually expect from a pig trap and what it is required to do. In addition we discuss the role of the various key trap components and how these differ for the different trap types.
In understanding what a trap does and what it consists of we look at innovations to the basic trap design and how this can further solve some of the practical design issues discussed.
Finally having designed a trap to cater for the known requirement we must of course understand the importance of looking at what is often a forgotten item. We must understand the value in identifying any issues and ultimately maintaining the equipment to protect our assets and more importantly life.
Interpreting Different Seismic Data Cubes Leads to New Insights for an Offshore Field, Abu Dhabi, United Arab Emirates
Authors: Khouri Naeema , El Awawdeh Raed , Shevchek Z J , Harris Christopher , Reilly J M , Zelewski Gregg , Gombos Andrew , Johns Mary 
Published: June 2009

Abstract
A series of new 3D seismic data reprocessing projects have provided the opportunity to develop an upgraded interpretation for a major Middle East offshore oil field. Using a number of different seismic attributes an improved structural and stratigraphic interpretation has resulted in significant changes that will be incorporated into a new generation of geologic models for simulation modeling of the Kharaib carbonate reservoir. The changes include a new fault framework that will influence future well placements and the overall development plan for the field.
Near-, mid-, far-, and full-stacks, spectral whitening and spectral decomposed data show different degrees of stratigraphic and structural resolution. The full reprocessing of a test cube included a separate processing flow for hydrophone and geophone data. The attributes of these individual cubes as well as the combined cube were studied. New insights were gained into remaining multiples in the data sets as well as differences in fault images.
Due to the use of multiple volumes and attributes the interpretation required a disciplined approach in the generation of new horizons and fault identification( Fig. 1). Criteria used for the fault definition for each data cube were clearly defined at the beginning of interpretation. From the new improved data, unsmoothed automated horizons were picked which led to better identification of small faults using horizon-based attributes. The new data allowed identification of pervasive NE-SW and N-S faults in parts of the field and to subdivide major faults into smaller faults at different stratigraphic levels. The new structural framework has been incorporated into the full field geologic models. Based on these encouraging results the same interpretation approach will be applied once a full-field reprocessing project is completed. Fig. 1Multi-volume interpretation approach