bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factor Identifies Hydrocarbon Recoverability and Type
Authors: Hamada G. M. 
Published: December 2007

Abstract
Resistivity data is normally used to evaluate water saturation using porosity values from porosity logs (neutron and density). Determination of initial oil (gas) in place is based on hydrocarbon saturation, porosity and thickness obtained from openhole logging data for a given drainage area. It is important not only to determine the initial hydrocarbon in place, but also to define the existing hydrocarbon moveability, indicating the recoverable hydrocarbon and its type.
This paper presents a new approach of hydrocarbon moveability factor (HCM). This factor is derived from shallow and deep resistivity data. The relation F = a/?m is correct in water saturated zones, in partially saturated zones this relation becomes invalid and it will give the apparent formation resistivity factor (Fa). Based on this idea the hydrocarbon moveability factor (HCM) has been derived. With scale goes from 0.0 to 1.0. It is found that for HCM less than 0.75, hydrocarbon is moveable and for HCM greater than 0.75, the hydrocarbon is immoveable. When HCM is less than 0.25, the moveable hydrocarbon is gas and for HCM greater than 0.25 and less than 0.75, the moveable hydrocarbon is oil. Field examples have been analyzed with the HCM factor. These field examples demonstrated the contribution of HCM in the field of hydrocarbon type identification and determination of hydrocarbon moveability from openhole resistivity logging.
Effect of Water Cut on Sand Production – An Experimental Study
Authors: Wu B. , Tan C. P. , Lu N. 
Published: December 2007

Abstract
It has been commonly acknowledged in the petroleum industry that water-cut increases sand production risk. A number of possible mechanisms have been proposed. This paper presents the results of a series of laboratory perforation collapse tests aimed at demonstrating and quantifying the water-cut effect on perforation failure and sand production.
The laboratory perforation collapse tests were conducted on weak sandstones obtained from both downhole and outcrop. The tests were performed under simulated in-situ effective stresses and drawdown conditions. Water was introduced into the flowing stream of either oil or gas at various stages of the tests to simulate water-cut. The failure and sand production processes were observed and recorded using a borescope in real time.
The results showed that the effect of water-cut on perforation strength and sand production depends on the mineralogical composition of the sandstone and the degree of residual water saturation. The effect is most significant for sandstones with high clay content and low residual water saturation and less significant for clean sandtones or those with high residual water saturation. The experimental results are discussed based on the chemical interaction between water and rocks, capillary stress and relative permeability. It is concluded that water saturation-induced rock strength reduction is the most significant factor governing peroforation failure and sand production. Although, perforation failure is a pre-requisite for sand production, the failure does not always lead to sand production.
Running of 13%Cr OCTG with dope-free premium threaded connections
Authors: Roberts Alun , Leech Andrew 
Published: December 2007

Abstract
Experiences of dope-free OCTG (Oil Country Tubular Goods) connections to date have been limited to carbon or low alloy steel threads1. However the higher galling tendencies inherent in stainless steel threads create a different challenge to their successful dope-free running. This study describes the successful development of a dope-free system for 13Cr and corrosion resistant alloy (CRA) connections from the initial development trials of a superior surface treatment system through to the deployment of a dope-free 13Cr offshore production string.
Coiled-Tubing Reverse Circulation - An Efficient Method of Cleaning Horizontal Wells in a Mature, Pressure-Depleted Field
Authors: Kumar P. S. , Al-Amri B. , Kouli P. , Van Gisbergen S. , Shidi S. , Ferdiansyah E. , Mowat P. 
Published: December 2007

Abstract
Several methods of cleaning deviated and horizontal wells have been developed over the years. One of the most common methods is running in with coiled tubing and circulating the solids out with a liquid or multiphase fluid. Solids tend to settle at the bottom or low side of the wellbore in highly deviated or horizontal wells. This makes the cleanout process inefficient in bringing the solids to the surface. In this field, most of wells are horizontal. One of matured fields in the northern directorate of Petroleum Development Oman manily produces from horizontal wells. The produced water is injected back into the reservoir. Scale is found in injectors and producers. The acid insoluble materials in these scales vary from 4% to 22%. Hence, cleanout of the horizontal hole is required in this field to keep the wells producing/injecting at their potentials. Various methods of cleaning like coiled tubing cleanout and reverse circulation through workstring during hoist/rig operations were tried in cleaning the horizontal wells. However, they were not successful in cleaning the horizontal hole. One of the main reasons is the loss of kill/completion fluid into the formation during well operations. In order to establish an effective cleaning method in this environment, it was decided to experiment the coiled tubing reverse circulation process in cleaning horizontal openhole injectors so that the same process could be extended for cleaning out horizontal producers.
This paper presents the results of coiled tubing reverse circulation trials carried out in three horizontal openhole injectors. The cleanout method was a combination of venturi junk basket and reverse circulation, with an initial venturi run being made to identify the top of fill and to remove the larger fill particles, followed by reverse circulation to remove the smaller particle out of the wellbore. Post cleanout injection rates increased on an average of 15% over the pre cleanout rates. Further to evaluate the effectiveness of this method, spinner runs were made along the horizontal openhole section before and after the cleanout jobs. The results revealed that injection was more uniform along the horizontal openhole section after the reverse circulation when compared to the few points of injection before the cleanout. Implementation of this reverse circulation process is now planned for producers in which it is not possible to remove acid insoluble materials by normal cleanout methods.
Identifying, Characterizing, and Locating Conductive Fault(s): Multiwell Test Analysis Approach
Authors: Al-Obaid R. , Al-Thawad F. M. , Gill H. S. 
Published: December 2007

Abstract
This paper presents a successful multi-well test analysis approach to identify and locate the geological feature(s) responsible for inter-reservoir communication between Lower and Upper reservoirs in ABQQ field. The study resulted in locating and identifying the nature of conduit(s) responsible for the direct communication between Lower and Upper reservoirs. Conductive fault(s) is/are observed repeatedly by five offset wells and clearly running between the two reservoirs. The location of the fault/faulted zone was predicted via an integrated approach including analyzing all the wells in the vicinity of the area under study and reviewing the drilling, logging and production data.
An interference test was conducted after producing Lower injected water from Upper reservoir. The test indicated a direct communication through five hundred feet of nonreservoir formation between the two reservoirs.
Many hydrocarbon bearing reservoirs are faulted, yet little information is available about the actual physical characteristics of the faults. Loss circulation while drilling horizontal wells, along with production logs provided tangible evidence of existing conductive faults. Drilling horizontal wells also indicated the existence of sub-seismic faults which cannot be detected by the 3D seismic resolution.
Better reservoir management decisions and more focused development strategies can be achieved through the utilization of the quantitative pressure transient analysis of those tests.
Krylov-Secant Methods for Accelerating the Solution of Fully Implicit Formulations
Authors: Klie H. , Wheeler M. F. 
Published: December 2007

Abstract
The present work is devoted to accelerate the nonlinear convergence of Newton-Krylov methods for solving fully implicit formulation in multiphase flow. The basic approach is to perform secant (Broyden) updates restricted to the Krylov subspace generated by the GMRES iterative solver. This approach is introduced as Krylov-secant methods. One of the most attractive features of these methods is to perform a sequence of rank-one updates without explicitly recalling the computation or action of the Jacobian matrix. Implications of these updates in line-search globalization strategies, computation of dynamic tolerances (forcing terms) and in the use of preconditioning strategies are presented. Numerical results show significant improvements over traditional implementations especially in those cases where nonlinearities increase due to stringent pressure and saturation changes.
Abrasive Cutting Technology Deployed Via Coiled Tubing
Authors: Loving S. W. , Ferguson A. , Hart R. 
Published: December 2007

Abstract
This paper will discuss the development of abrasive cutting technology deployed via coiled tubing for cutting production tubing, drill pipe, drill collars, exotic stainless steel completion components, single strings of casing and multiple strings of casing. This technology is performed utilizing a sealed bearing, positive displacement motor and a cutting head along with conventional coiled tubing tools and conventional coiled tubing. This technology gives operators an additional tool when severing of the drill string or production tubing is required.
Additionally the paper will discuss perforating tubing and casing using abrasives, particularly in horizontal wells where conventional wire-line operations are not possible.
The paper will discuss: Utilizing a positive displacement motor to perform abrasive cuts via coiled tubing,Design and testing phases of the abrasive cutting system,Initial field runs to prove the viability of this technology,Total jobs completed to date,Lessons learned throughout the process,Where this technology leads from here.
The paper will also discuss future applications for this technology which include cutting casing for plug and abandonment programs, permanent packer retrieval, and abrasive perforating all deployed via coiled tubing.
OPEC: Floating Supply for a Balanced & Stable Market
Authors: Talabani S. 
Published: December 2007

Abstract
OPEC was formed as a joint action between five countries in 1960 in Baghdad to set a fair price for crude oil in the world market.Today, eleven members account for 40% of world oil production and 65-70% of proven oil reserves.
OPEC members regularly discuss oil prices and set crude oil production quotas. OPEC revenue has grown over the last year, but instability in revenue has been repeatedly related to geopolitical crises, instability in one or more OPEC member states, or lower world demand.OPEC pricing is set based on an arithmetic average of a basket of seven crude types; in practice, this is unhealthy for the crude price and always fails to follow the market.Furthermore, there is one trillion barrels of crude worldwide awaiting cost effective technology to make it ready for production.This would possibly results in better price stability in the crude oil market.
OPEC price, based on basket trading, was set for 10 -20 days as $22.0 - 28.0 for adjustment.This has not been forced in the market since it was accounted.
Until the European Union created a unified currency, the US dollar has been (and still is) the dominant currency since 1945 and handles over 70% of world official exchange reserves.
Will this state of affairs change? Will the oil (and possibly gas) price become stable whilst subject to rules other than that of supply and demand? Can the Euro replace the Dollar in the trading of crude oil?Would it be better for OPEC members to base production quotas on regulations other than those currently used?
Most forecasts of prices and quotas face difficulties in finding rules to follow. This paper discusses ways and means for better crude market stability.
Developing and Maintaining a High Performance Culture in a Well Engineering Environment-Making Technical Limit Work
Authors: Gallagher K. T. , Jones G. D. 
Published: December 2007

Abstract
Pursuit of performance is fundamental in today's Well Engineering world but are you getting all that you can out of your team? Detailed procedures and systems, incentives and initiatives are often used but the real key may be something else-the people and the organisational culture that they work within.
It has been 10 years since the introduction of Technical Limit1, and in the interim human resource specialists have widely argued that people are the sole source of sustainable competitive advantage in an organisation rather than systems and processes2. Translating this to a well engineering environment, our people should no longer be considered a commodity item. Issues such as performance management, training and development, organisational learning, developing a performance mindset (culture), and the ability to build individuals into a cohesive team all affect drilling and completion performance. These issues are often highly interdependent; such is the complexity of managing people.
We believe that by taking the learnings from years of Technical Limit application and coupling them with current thinking in developing a high performance workplace culture, the result yields a high performing drilling and completions team.
Managing Wellbore Instability Risk in Gas-Hydrate-Bearing Sediments
Authors: Tan C. P. , Freij-Ayoub R. , Clennell M. B. , Tohidi B. , Yang J. 
Published: December 2007

Abstract
With the petroleum industry endeavouring to develop oil and gas fields in deepwater and to increase its activities in onshore arctic environments, greater emphasis should be placed on quantifying the hazards to drilling operations posed by gas hydrates. In spite of gas hydrate-bearing sediments having been drilled successfully in the past, it is important, as future drilling operations progress into deeper and ultradeep waters, to develop a sound understanding of gas hydrate-related hazards and thereby identify ahead of time when problems are likely to occur. It is also highly desirable to define the envelope of risk-free operations so that unnecessary costs and delays associated with mitigation of the problems are not incurred.
This paper describes the specific requirements to develop a comprehensive risk management capability for drilling in gas hydrate-bearing sediments. The methodology adopted concentrates on reducing risk and uncertainty associated with gas hydrates and associated shallow gas geohazards in deep water. These will be achieved by means of determining the petrophysical, mechanical and thermodynamic properties of gas hydrate-bearing sediments, and developing a fully coupled model for wellbore stability in the sediments, and methodology for drilling fluid design optimization and a risk assessment and optimization framework. Examples of laboratory measured petrophysical and mechanical properties of gas hydrate-bearing sediments, and results of time- dependent wellbore stability in such sediments are presented and discussed.
Gulf of Mexico Deepwater Well Completion with Hydrate Inhibitors
Authors: Pakulski M. , Qu Q. , Pearcy R. 
Published: December 2007

AbstractUtilization of low-density completion fluids and packer fluids is becoming more popular in oilfield deepwater operations. These low-density fluids must first meet the expected nonformation damage aspect, found with clear brine fluids, and consequently not impede future gas or oil output from wells. However, formulation of such fluids has some unique challenges to overcome in the deepwater environment. Especially for completion fluids in deepwater wells, they have to work under significant pressure regimes and low mudline temperatures, conditions favoring the formation of gas hydrates. Methanol is the only known thermodynamic hydrate inhibitor allowing formulation of a low density and hydrate protected fluid, while glycols and salt solutions can add undesired density to the fluids. On the other hand, high volatility, toxicity and flammability of methanol make this chemical a necessary "evil" in oilfield applications.In the particular case reported here, a multiwell deepwater project located in a Gulf of Mexico (GOM) deepwater area required a low-density packer completion fluid to optimize operational requirements and the operator insisted the usage of methanol be limited or possibly eliminated. With the particular reservoir pressure and low mudline temperature, as low as 1.67°C (35°F), the gas/fluid system was severely at hydrate conditions. Commingling a Low Dosage Hydrate Inhibitor (LDHI) being a combination of thermodynamic hydrate inhibitor (THI), kinetic hydrate inhibitor (KI) and antiagglomerant (AA) with a low-density fluid was a viable solution to the problem. A novel low-density packer fluid containing a long lasting LDHI was invented for the application.Working with the new fluid is a safer alternative; the fluid is more acceptable than the high methanol product. The hydrate-inhibited system was placed inside the annulus as packer fluid in a unique fashion and in coordination with other packer fluids. This novel placement method has been applied in multiple GOM deepwater wells. This paper highlights the development of the hydrate inhibitive packer fluid technology and its successful field application.
Controls on Fracturing in Carbonate Rocks
Authors: Peacock D. C. P. , Mann A. 
Published: December 2007

Abstract
Sedimentology (lithology, sedimentary structures, bed thick-ness, mechanical stratigraphy, the nature of bedding planes), structural geology (tectonic setting, palaeostresses, subsi-dence/uplift history, proximity to faults, position in a fold, timing of structural events, mineralisation, the angle between bedding and fractures) and present-day factors (orientations of in situ stresses, fluid pressure, perturbation of in situ stresses, depth) can all control the nature and distribution of fractures within carbonate rocks. Understanding these factors requires traditional geological skills, including the analysis of core, borehole images and exposed analogues.
Evaluation of Cationic Water-Soluble Polymers With Improved Thermal Stability
Authors: Fernández I. J. 
Published: December 2007

Abstract
Acrylamide-based water-soluble polymers are used in operations such as drilling, water flooding and water conformance. A drawback of these polymers is that the primary amide group is sensitive to hydrolysis at elevated temperatures. This fact sometimes becomes a problem in deep reservoirs, because the solutions properties change when the degree of hydrolysis of the polymer increases and, in a media of high salinity and water hardness, the precipitation of the polymer may occur.
To improve the thermal stability different copolymers have been prepared. The comonomers used for this purpose are mainly N-alkyl substituted acrylamide derivatives and of particular importance N-vinyl pyrrolidone (NVP). The aim of the present work is to evaluate the improvement of the thermal stability of cationic water-soluble polymers based on acrylamide when NVP is introduced as a comonomer, in order to know the amount and kind of incorporation of NVP required to get a polymer useful for applications under severe conditions of temperature.
Several copolymers and terpolymers of acrylamide, a cationic monomer and NVP were prepared. The products were evaluated in terms of the thermal stability of the primary amide group and the fraction of retention of the intrinsic viscosity in aging tests at 248°F. The introduction of NVP limited the hydrolysis of the primary amide groups. When the content of NVP increased in the terpolymers the hydrolysis degree reached after the aging was lower. In addition, the distribution of the monomers in the polymer chain also showed an influence in the improvement of the thermal stability. The results made possible to suggest a mechanism for the stabilization of the amide group by NVP.
These results provide information to prepare a cationic water-soluble polymer that could be used for applications where severe temperature conditions are expected.
Modeling of Geomechanics in Naturally Fractured Reservoirs
Authors: Bagheri M. , Settari A. 
Published: December 2007

Abstract
Conventional modeling of fractured reservoirs treats fracture system permeability and porosity as static (or pressure-dependent) data. Recent attempts at coupling geomechanics focused on the permeability, but used crude empirical relations and treated the fluid flow as single porosity. This study takes advantage of joint mechanics theory to develop general, rigorous coupling between fluid flow equation and deformation of fractured media. Both porosity and perm-eability coupling is considered.
The geomechanical part uses the equivalent continuum approach, considering both rock and fracture deformation properties. Multiple sets of fractures with any dip and strike angle can be defined. The stiffness of fractures varies with the effective stress according to a law typical for joints. The resulting pseudo-continuum stiffness matrix equations were verified by comparing with models using explicit modeling of fractures and analytical anisotropic poroelasticity theory.
The main novelty of this work is that the geomechanics solution is decomposed into matrix and fracture parts and used to compute their dynamic porosity and permeability separately. This approach captures rigorously the effect of fractured media deformation on the dual porosity flow part of the coupled system, and allows the permeability and porosity variations to be based on measurable joint properties. Generally, fracture deformations produce changes of the permeability tensor in both magnitude and orientation, which in turn influences reservoir flow and compaction behavior.
The main issue studied was the variation in the permeability of the fracture system. The examples show that fracture deformation has a significant effect on productivity or injectivity, and that anisotropy of the permeability tensor develops from deformation. The results provide an initiative for implementing the case of full tensor permeability.
Faster and More Accurate Data Collection for Microbiologically Influenced Corrosion
Authors: Zhu X. , Kilbane J. J. 
Published: December 2007

Abstract
Microbiologically Influenced Corrosion (MIC) is a significant problem affecting the oil and gas industry, particularly in production operations. The most commonly used means of monitoring MIC is to quantify the number of bacteria capable of growing in various microbial growth media after inoculation with water samples obtained from pipelines/production operations. However, it is becoming increasingly apparent that the number and type of bacteria present in environmental samples, as measured by microbial growth tests, does not correlate well with the presence or extent of corrosion in pipelines, and that microbial growth tests are slow and inaccurate. To address this issue GTI has developed genetic techniques to characterize the types and abundance of bacterial species present in oil and gas production operation samples more quickly and with greater accuracy than was previously possible. The ability to obtain MIC data faster and more accurately will assist the oil and gas industry in better understanding and controlling MIC.