bluuebunny/crossref_metadata_2025 huggingface dataset:
The Fracture Network Model of Shen 229 Block Buried Hill: A Case Study From the Liaohe Basin, China
Authors: Yuzhong X. , Jichang Z. , Tailiang F. , Zhong C. , Chunming J. , Lihui Z.
Published: December 2007

High oil production from the Proterozoic Formation of Shen 229 block in Da mingtun depression, Liaohe basin, China, indicate the presence of naturally fractured reservoirs whose reservoir's production potential is dominated by the structural fracture. A consistent structural model and a good knowledge of the fracture systems is therefore of key importance in reducing risk in the development strategies. So data from core and image logs have been collected to account for the basic characteristics of fracture, and then the analysis results were integrated with the structural model in order to restrict the fracture network development during the structural evolvement.

The structural evolution of the Proterozoic reservoir through time forms the basis for understanding the development of the 3D fracture system. Seismic interpretation and formation correlation were used to build a 3D geological model. The fault blocks that compose the Proterozoic formation reservoir were subsequently restored to their pre-deformation states using 3D structural modeling software. From here, the structures were kinematically forward modeled to simulate the structural evolution of the reservoirs.

At each time step the dilatational and cumulative strain was calculated throughout the modeling history. The total strain record the total spatial variation in the reservoir due to its structural history, together with core data, well data and the lithology distribution, were used to simulate geologically realistic discrete fracture networks. The benefit of this technique over traditional curvature analysis is that the structural evolution is taken into account, a factor that mostly dominates fracture formation.
HAZOP Studies for Grass-Root Field Development Project
Authors: Saadawi H.
Published: December 2007

The North East Bab (NEB) Project is currently under construction by Abu Dhabi Company for Onshore Oil Operations (ADCO). It is a grass root field development project. New production facilities are installed to handle oil, gas and water production from three separate oil fields; Al Dabbiya, Rumaitha and Shanayel.

In accordance with the project HSE plan, a HAZID (Hazard Identification) study was conducted during the conceptual design phase.HAZOP studies were carried out during the FEED and EPC phases of the project.

This paper describes the role of HAZOP in a complex major project involving full field development.Topics covered include: project description, project HSE plan, HAZOP logistics, main HAZOP findings, follow-up and implementation of the HAZOP recommendations as well as the lessons learnt. Finally, the paper concludes by making recommendations on the effective way to implement HAZOP studies for new projects in an E& P environment.
An Effective Approach for Successfully Drilling Into the Naturally Fractured Reservoir (NFR): A Field Application Study
Authors: Hou X. , Liu G. , Hao L. , Tian A. , Liu Y.
Published: December 2007

Naturally Fractured Reservoir (NFR) characterization represents an increased focus for oil and gas companies as it becomes more and more admitted that they represent a substantial part of their portfolio 1. However the complexity of successfully drilling through fractured reservoirs pushed several service and integrated companies to tackle the fractured reservoir drilling challenge. Moreover the use of effective approaches with the help of UBD and new air technologies are started to show successful results. Tabnak Structure has developmental formation fissure and solution hole, low pressure coefficient, and good connectivity. Therefore, for the low pressure fractured carbonate rocks formation and tight hole of clay shale of Laffan and Kazhdumi formation, it is easy to cause severe circulation loss, serious formation collapsing and frequent pipe sticking. Air drilling and air/foam drilling technology are adopted for the practice operations of Tabnak Structure, which high circulation rates effectively resolved the excellent hole cleaning and avoided the most severe lost circulation zone in 36", 26" and 17 1/2" large hole intervals.

This paper presents the drilling application of coping with large interval of salt and anhydrite. We first cover the drilling difficulty and challenges of designing and operating a large hole into lost circulation formation which has so far proved difficult to drill with conventional drilling method. We then look at the application of air/foam drilling to resolving the lost circulation and hole cleaning problems, and at the same time point to valuable lessons learned from failures.
A Comparative Analysis of Waterflooding Projects using Horizontal Wells
Authors: Algharaib M. , Gharbi R. B. C.
Published: December 2007

The use of horizontal and multilateral wells in oil industry has increased rapidly during the last two decades.The main reason for this upsurge is that horizontal and multilateral wells provide large contact area with the reservoir, and therefore enhance the well productivity or injectivity better than conventional vertical wells.The high productivity coupled with the recent advances in drilling technology for horizontal and multilateral wells has made their application to be an economically viable option.

In this study, the performance of non-conventional wells in water flooding projects was investigated using numerical simulation techniques.Extensive three-dimensional, fine-mesh simulation runs are performed to determine the oil recovery by non-conventional wells under different operating/reservoir conditions.Results show that the pattern used has a significant effect on the displacement performance of non-conventional wells.The study shows the various conditions under which non-conventional wells will perform better than the use of conventional vertical wells
Fracture Flow Property Identification: An Optimized Implementation of Discrete Fracture Network Models
Authors: Basquet R. , Cohen C. E. , Bourbiaux B.
Published: December 2007

Proposal

The hydraulic characterization of naturally fractured reservoirs is a key point to provide valid flow properties to full-field simulation models. This calibration and validation step is based on the simulation of dynamic data such as flowmeter, transient or interference well tests. Recently, a methodology has been proposed to simulate such tests on Discrete Fracture Network (DFN) models derived from field fracture data integration. However, the drainage area of a well test in a fractured reservoir is generally large, thus leading to numerous computation nodes, especially in the presence of dense fracture networks. In such situations, the CPU time required for a single well test simulation for instance can reveal itself prohibitive.

This paper proposes an original approach to simplify the DFN model in order to reduce drastically the number of fracture nodes, while keeping the same hydraulic properties. This approach keeps the actual fracture network geometry close to the well and replaces the fracture network far from the well by a simplified discrete fracture network. This DFN simplification is performed through an homogenization procedure keeping the same matrix-fracture storativity ratio and interporosity flow parameter. A sensitivity study was carried out to define the area around the wellbore where the fracture network can be simplified. We also defined a connectivity criterium to ensure a representative flow coupling between the actual near-well fracture network and the simplified distant network.

Well tests simulations on this innovative DFN model are compared with simulations on the actual dense fracture network. Then we considered a 3D problem of well testing in a realistic field context. For both cases, the well test signature is not affected by the DFN simplification procedure, but the computation time is reduced drastically, by nearly two orders of magnitude (from 1 hour to 5 minutes CPU for instance). These tests illustrate the major contribution of this new approach. Actually, numerical flow simulation on DFN models can now be carried out at the well drainage area scale and thus be used to tune the field-measured well tests responses: a determinant step to validate the fracture network geometry derived from geological data and to identify fracture conductivities.
How Multi-Component Seismic Can Be Used To Manage Fractured Carbonate Reservoirs
Authors: Kristiansen P. , Gaiser J. , Horne S.
Published: December 2007

Fractured reservoirs have been encountered worldwide and in general they are profitably produced, however it is safe to say that none of them have been depleted efficiently. As the seismic industry focuses more on production and development it is becoming more important to recognize the presence of fractures for optimal reservoir management.

In reservoirs producing primarily from secondary porosity like fractures, the flow is largely controlled by the fracture system and characterizing these fractures is key to effectively managing these reservoirs. Aligned fractures will affect the average stiffness of the rocks even when fractures are smaller than seismic wavelengths. Small scale aligned fractures lead to variations in the seismic velocities that are directionally dependent, an effect known as anisotropy. Measuring this seismic anisotropy provides information on the fracture systems properties, such as fracture density and orientation. Such information can be used to identify sweet spots and in general be used for better reservoir management, like guiding directional and infill drilling.

Since fractures are often nearly vertical to bedding the dominant seismic effect is azimuthal anisotropy, which is observed both on P- and S-waves. AVOA (azimuthal AVO-effect) and variations in the NMO velocities have been used to estimate P-wave anisotropy. S-waves will split into one fast and one slow mode and this splitting is very sensitive to small changes in the subsurface. The fast shear-wave direction aligns with the fracture strike and the amount of time splitting between the fast and slow mode depends on fracture density. Apart from the difference in sensitivity between the P- and S-wave measurements there are attributes of the fracture system that can only be observed on the S-wave data. The asymmetry in the converted waves (PS-data) can say something about the tilt of the fractures. Multicomponent seismic provides access to both the P- and S-wave azimuthal information. Combining these two can enable the extraction of information about the fluid in the fractures. In this paper we will give an overview of the theory and several cases where multi-component data has been used to characterize fractures and fracture attributes.
Artificial Neural Networks Models for Predicting PVT Properties of Oil Field Brines
Authors: Osman E. A. , Al-Marhoun M. A.
Published: December 2007

Knowledge of chemical and physical properties of formation water is very important in various reservoir engineering computations especially in water flooding and production. Ideally, those data should be obtained experimentally. On some occasions, these data are not either available or reliable; then, empirically derived correlations are used to predict brine PVT properties. These correlations offer a handy and an acceptable approximation of formation water properties. However, the success of such correlations in prediction depends mainly on the range of data at which they were originally developed. These correlations were developed using linear, non-linear, multiple regression or graphical techniques.

Recently, researchers utilized artificial neural networks (ANN) to develop more accurate oil PVT correlations. The developed models outperformed the existing correlations. However, there is no similar research done so far to utilize the power of ANN in developing similar models for formation waters. In the present study, two new models were developed to predict different brine properties. The first model predicts brine density, formation volume factor (FVF), and isothermal compressibility as a function of pressure, temperature and salinity. The second model is developed to predict brine viscosity as a function of temperature and salinity only. An attempt was made to develop a comprehensive model to predict all properties in terms of pressure, temperature and salinity. The results were satisfactory for all other properties except for viscosity. This was attributed to the fact that viscosity depends only on temperature and salinity. The models were developed using 1040 published data sets. These data were divided into three groups: training, cross-validation and testing. Radial Basis Functions (RBF) and Multi-layer Preceptor (MLP) neural networks were utilized in this study. Trend tests were performed to ensure that the developed model would follow the physical laws. Results show that the developed models outperform the published correlations in terms of absolute average percent relative error, correlation coefficient and standard deviation.
Mechanical Methods of Reducing Torque and Drag in Extended-Reach Wells Facilitate Continued Canadian Foothills Development
Authors: Berry M. , Dousett J. , Cowling D.
Published: December 2007

This paper examines the use of mechanical torque and drag reduction tools for overcoming drillstring limitations encountered while drilling extended-reach wells in the Waterton area of Alberta, Canada. Three highly deviated new wells and two extended-reach horizontal re-entries were drilled using the tools. The paper summarizes the challenges of drilling wells in this area, the use of an engineering software system to optimally position the mechanical torque and drag reduction tools in the drillstring, and the results achieved.
Case History: Using a Communications Protocol to Reduce Wiring Costs During Construction of Well Test Headers
Authors: Norman M. , Denke L.
Published: December 2007

We installed several systems that used Actuator Sensor Interface (ASi) bus to simplify and economize the wiring of valves on well test headers1 in California oilfields. Using a communication protocol like ASi bus (or DeviceNet) reduces the amount of wiring and conduit that must be purchased and installed for each well test header. We have achieved cost reductions by using ASi bus communication on well test headers. As with introduction of any new technology, there were numerous "lessons learned." We present our recommendations for installing ASi bus systems.
Investigations Into The Suitability Of Galvanic Cathodic Protection Systems For Long Term Protection Of Buried Pipelines In Desert Locations
Authors: Hawkyard J. , McGlone D.
Published: December 2007

Proposal

The paper outlines the Khuff gas distribution system operated and maintained by The Bahrain Petroleum Company (BAPCO). It will detail the types of cathodic protection installed and areas of apparent premature failure of galvanic cathodic protection systems

In 1998 a number of new pipelines were installed and magnesium sacrificial anode systems designed and installed. At about the same time some remedial work was undertaken on existing pipelines to replace depleted magnesium anodes.

During a recent routine survey of the cathodic protection systems it was found that a number of these anodes had apparently failed prematurely and were not achieving proper protection levels.

The paper will outline investigations carried out into the failed anodes, reasons for failure and recommendations for remedial work.

This paper will focus on the use and suitability of sacrificial anode systems versus impressed current systems for the long-term cathodic protection of buried pipelines in desert and reclaimed land areas.
Nonconventional Medium-Wavelength Static-Correction Method to Overcome Shallow Gas Anomaly Problem
Authors: Noor Y. , de Tonnac G. , Bonnafé J. , Waluyo A.
Published: December 2007

Sisi and Nubi are two gas fields operated by Total E&P Indonésie, located 20 km offshore from the Mahakam Delta (East Kalimantan).

In order to design the future field development, a 1000 km2 3D seismic data set was acquired during 2003 that covered the field area and beyond. There are two main challenges in processing this data:

Push-down effects. This problem is well known in the Mahakam Delta area and is associated with shallow gas anomalies characterized by very low seismic velocities. Amplitude distortion. Shallow gas anomalies also act as amplitude masks

Total E&P Indonésie solved the problem using non conventional medium wavelength static corrections. The processing method was established using WesternGeco technology in cooperation with Total expertise.
Arthit Log-Derived Permeability Modeling Project
Authors: Stephens S. , Pisutha-Arnond S. , Schoenicke O. , Vatthanavit K. , Jiang L.
Published: December 2007

A log-derived permeability prediction model for the new Arthit Field in the Gulf of Thailand has been successfully developed based on available cores and well test results. Accounting for more rock and fluid parameters than just porosity alone, the log-based algorithm has proven to be better-equipped to predict permeability with less uncertainty than traditional K-PHI cross-plots. The Arthit permeability model considers not only porosity, but variations in clay mineral composition and clay volume.

It is a well-known fact that sands having the same porosity will not necessarily have the same permeability due to other reservoir factors affecting permeability. A traditional K-PHI cross-plot employing a straight-line correlation of permeability and porosity cannot be expected to provide the best estimate of rock permeability due its indifference to changes in the rock matrix. The Arthit log-derived permeability model (K-Log) considers not only porosity, but variations in clay mineral composition and clay volume. It eliminates the need to subdivide data by rock type, does not require a semi-log scale correlation, and reduces the uncertainty of prediction. Clay diagenesis and reservoir temperature were identified as important parameters affecting permeability where predictions in shallow, low-temperature zones poorly matched actual measurements but reliably matched measurements at higher temperatures.

The model currently contains vertical definition by geologic formation. Areal definition should be possible in the near future as more permeability measurements are gathered from various geologic areas within Arthit resulting in distinct mineral factor sets for major geologic areas such as graben, basement flank, or basement high. Engineering applications currently planned for permeability modeling include well completion design, high-CO2 gas blending, field production forecasting, sand control, and reservoir simulation.
Belanak Development: Batch Drilling Operations in Natuna Sea
Authors: Septiantoro A. , Bujnoch J. , Welbourn E.
Published: December 2007

In October 2003, development drilling of the ConocoPhillips Indonesia Inc. Ltd operated Belanak Field commenced when the platform rig was rigged up over a previously installed twenty-four slot platform. Drilling commenced with the objective of drilling and completing ten slant directional wells and six horizontal wells.

The objective of the Field development was to have high production rates available when the FPSO facilities arrived approximately twelve months later. Since the wells had to be pre-drilled before first production, it made sense to utilize a full batch drilling concept in order to minimize costs.

The 13-3/8" surface casing strings were successfully batch set on all sixteen wells. This section was completed fifteen days ahead of budget time and set several world record penetration rates for a 16" tricone bits.

The 9-7/8" hole/7-5/8" casing sections were batch set in ten wells. Most well objectives were met and the performance was exceptional in some wells, but, this section was plagued by surface and downhole equipment failures.

The 12-1/4" hole/9-5/8" casing sections were batch set in six wells. All well objectives were met including landing all wells in the reservoir at 90°. Time to complete this section was longer than expected due to inconsistent BHA response.

The 8-1/2" horizontal hole sections were then drilled and completed with a 3,500 ft average hole length for the same six wells.

This paper will focus on the drilling operations and discuss the performance and problems encountered. The Belanak drilling team was committed to continuous improvement by capturing data and immediately implementing the learning's. This commitment to maximize the learning curve resulted in minimizing cost and a successful intensive batch drilling operation.
What is the Source of Drilling and Completion Data?
Authors: Nakagawa E. , Damski C. , Miura K.
Published: December 2007

The industry commonly accepts that information from actual drilling, completion, and workover operations should play an important role in the analysis of performance, comparison against plans, optimization of future operations, and operational safety. It also expects that considerable operational savings would come from the effective use of such information.

In many cases, however, companies cannot experience these gains, even when using sophisticated reporting systems and software tools, basically, because of inappropriate information management processes. For example, sometimes, companies do not store planning information in their databases and, thus, cannot compare planned vs. actual; in other cases, even when planning information is kept, it is difficult to match them with actual operations; most commonly, the operations are not identified or coded properly, making it impractical for the user to perform any reasonable analysis.

This paper describes a new methodology and its practical implementation, which allows for the realization of all the benefits that reliable data can bring in. The basis of the process is the report on planning concept, which changes the current reporting paradigm used by the industry. In this process, the source of operational information shifts from the rig-site to the planning office. In addition, the process requires a detailed design of the operational sequences, levels of granularity, and operational code standards.
3D Post-Stack Acoustic Impedance Inversion Results for Kijing and Malong Fields, South Natuna Sea
Authors: Badachhape A. R. , Abdurahman A. R.
Published: December 2007

Post-stack acoustic impedance inversion was performed at Kijing, Malong, and Buntal fields. The results allow detailed reservoir characterization of the fields to be done, and predict the location of porous, reservoir-quality sands, and in many cases, reservoir-quality sands that contain gas. Several aspects of the inversion results prove to be useful that cannot be achieved through the use of seismic analysis alone. The removal of wavelet effects (tuning, extra events due to constructive wavelet sidelobe interference, and dimming due to destructive wavelet sidelobe interference) is one important enhancement. Seeing the impedances as layer properties instead of as interfaces allows information about the sands and shales to be observed. Increase in bandwidth, both on the low end with the introduction of a good low frequency model from the interpolation/extrapolation of well log impedance along interpreted horizons and the use of geologic constraints, and on the high end due to the use of a spectral whitening deconvolution operator and proper inversion parameters produces increased resolution.

The inversion results at Kijing, Malong, and Buntal fields may be used to discern details about the reservoir sands, especially in conjunction with the current geologic and geophysical information from conventional seismic data, well logs, analogs, etc. 3D visualization of the reservoir shows the structure of the sands, most of which are channelized.
Effect of Temperature on Relative Permeability for Heavy-Oil Diatomite Reservoirs
Authors: Schembre J. M. , Tang G.-Q. , Kovscek A. R.
Published: December 2007

Thermal recovery is the most utilized enhanced oil recovery method. The modeling of thermal recovery processes not only requires relative permeability functions, but also information about the effects of temperature on these functions. There are significant challenges encountered when estimating relative permeability from laboratory data, such as accuracy of measurements and generalizing assumptions in the interpretation techniques. A novel method is used here to estimate relative permeability and capillary pressure from in-situ aqueous phase saturation profiles obtained utilizing computerized tomography (CT) scanning during imbibition experiments. Relative permeability and capillary pressure functions are interpreted simultaneously including nonequilibrium effects. Moreover, the use of B-spline coefficients allows the estimation of arbitrary shaped functions. Results obtained show a shift toward increased water-wettability with increasing temperature for diatomite reservoir core. The measured changes in relative permeability are linked to the effect of temperature on surface forces and ultimately to rock-fluid interactions.
Introduction of New PDC Cutter Technology Increases Drilling Efficiency in Central US Wells
Authors: Yoosuf S. , Dunbar B.
Published: December 2007

In the Central US, recent application of new PDC cutter technology throughout the drilling of more than 40 wells has produced an impressive step change in drilling efficiency. The step change is clearly demonstrated by real time cost savings and a significant reduction in drilling times.

To date, more than 240,000 oil and 59,000 gas wells have been drilled in the Central US in the State of Oklahoma alone. In an attempt to improve drilling economics and reduce operational risks in the region, operators and bit manufacturers have been working as a team to develop PDC drill bits that can drill faster and deeper into harder, complex geological formations with high compressive strengths and abrasive properties. In addition, the longer runs achievable by fixed cutter PDC bits reduce the risks involved in running roller cone designs and the likelihood of problems during trips in and out of the hole. With this goal in mind, many different bit types with developmental PDC cutters recently have been run in the Central US region.

Drilling performance showed significant improvement when a drill bit design modification was introduced that replaced existing cutters with a newly developed PDC cutter designated Z3™. Introduction of the new cutter, the only bit design parameter that was changed, resulted in consistent performance improvements in penetration rate and footage drilled in applications throughout the region. For example, in South Central Oklahoma, a PDC bit design with the new cutters improved penetration rates to as high as 175ft/hr, where existing PDC bit designs averaged 90-100 ft/hr. In Western Oklahoma, a bit with the new cutters drilled more than 800 feet deeper than offsets, the first bit in the area to drill the entire section to TD. In the Texas Panhandle, the bit designs consistently improved footage performance in the hard formation applications.

This paper describes a new cutter technology which offers significantly greater abrasion resistance as well as resistance to thermal mechanical failure than have previous cutters. This paper also discusses various cases studies from the US Central area that show the performance improvements resulting from use of the new cutters. An economic analysis demonstrates the cost savings realized.
Cutting-Edge Materials Technology Elevates Drilling Performance in Soft-Formation Applications
Authors: Caraway D. , Card K. , Pullen S.
Published: December 2007

Drill bits manufactured using the powder forge (PF) process rather than conventional welded hard metal are setting new standards for soft formation drilling. The PF process provides unique advantages in hardmetal placement and metallurgical design thus allowing cutting structures capable of drilling a variety of formations from IADC 11 to 41 and fixed cutter type applications with superior performance. This paper will:

Explain the PF manufacturing process, highlighting lessons learned in the development learning curve. Review the benefits of producing bits using this process. Examine actual field results showing the cost savings available through application of cutting edge technologies. Discuss the improved wear characteristics of PF bits that has led to changes in operational variables such as weight on bit, rpm, hydraulic horsepower and monitoring drilling progress based on changes in rate of penetration.
Integrated Management of Water, Lean Gas, and Air Injection: The Successful Ingredients to EOR Projects on the Mature Handil Field
Authors: Duiveman M. W. , Herwin H. , Grivot P.
Published: December 2007

The future of large very mature oilfields relies upon the successful application of EOR techniques. This paper discusses from the Handil field case, the more useful concept and practices that are applicable to optimize oil recovery in a multi-layer, multi reservoir waterflooded field.

The Handil field, discovered in 1974, is a giant mature oilfield located in the Mahakam Delta, Indonesia. The field was developed using conventional oil recovery methods: natural depletion and peripheral water injection and produced a maximum of 200,000 BOPD in the late seventies. Currently, the oil recovery is around 50% with a 15,000 BOPD production at high watercut.

The Handil EOR lean gas injection project was started in November 1995 on five reservoirs and following its positive result was extended with six reservoirs in 2000. In 2003, an integrated study on the largest EOR reservoir was performed to assess the projects’ performance. This included 3D geomodeling, reservoir simulation and chemical tracer injection. The study permitted to track the main effects of the gas injection, to identify "bypassed oil" areas and to define reservoir management guidelines for the other lean gas injection reservoirs.

As field scale application of the gas injection technique is not sustainable since the gas is exportable, two other techniques are currently being evaluated as an alternative.

Second Contact Water Displacement (SCWD) is planned to be introduced on the maturest lean gas injection reservoirs. Simulation studies forecast potential for this technique which also allows decreasing the volumes of injected gas.

An Air injection pilot on a waterflooded reservoir was started in 2001. First results are encouraging but the injection was temporary suspended due to injector well problems after 6 months of injection. The project was comprehensively studied by compositional and thermal simulation and intends to restart early 2005.

Integrated studies of the Handil reservoirs provided in-depth understanding of EOR mechanisms. This resulted in the ability to better model field performance and to forecast tertiary oil production more accurately.
Deepwater Subsea Well Intervention – The Future Solution
Authors: Dick A. J.
Published: December 2007

The Expro Group has embarked on the development of subsea intervention technologies that extend far beyond the limits of current technology. This paper provides an up to date picture of this development, the markets that will be served and how this ground breaking innovation can now deliver operators with the capability to produce subsea assets by reducing CAPEX and efficiently controlling wells remotely without concern of lower field recovery (<20%) rates. Expro can achieve this by swiftly mobilising solutions, which are low cost (up to 75% savings on current rig solutions) whilst also highly reliable.

Applications of this solution fall into several key categories:

Subsea Wells - whether vertical or horizontal trees, the technology being developed can enable improved subsea well intervention, a primary concern being prohibitive costs offsetting intervention that reduces absolute recovery Deepwater - increasing the subsea sector's growth whilst providing new challenges that further highlight the need for more cost effective solutions Extended Reach - when subsea wells and tie-backs become prohibitively risky and costly, there is increasing demand for extending from existing templates, Rigless intervention solutions may tip the balance back. Low Cost Wells - as above, why invest in a smart well when a low cost simple intervention can provide the necessary solution.

In summary, this paper will give a high level overview of the challenges ahead and the way forward - Expro's vision, incorporating the engagement of key ‘supermajor’ players / technology users through a Joint Industry Project (JIP).
Specialised Designs for Complex and Record Drilling Project
Authors: Beiriger C. , Bujnoch J. , Bealessio T. , Hudson C. , Farrar J. D.
Published: December 2007

The Belanak field in the Natuna Sea of Indonesia is located 253 miles northeast of Singapore in 300’ water depth (Figure 1). The field development consists of two wellhead platforms, with 16 wells drilled from platform A, and 18 wells planned for platform B. Due to the remote location of the development, and the space and storage limitations inherent to a platform rig, logistics and equipment design were the major front-end engineering issues of the drilling project. The early concerted effort of the operator and contractors to front-end planning and design led to the realization of several drilling records and first-time accomplishments in the Natuna Sea.
Using Third-Party Certifications to Deliver HSE Performance
Authors: Kraus B.
Published: December 2007

Proposal

There is rising concern that current approaches to environmental management systems are yielding little in the way of meaningful environmental performance improvement. No small concern because the scale of the investment in EMS is colossal, but often underestimated. Over 95% of the real economic cost of EMS is attributable to factors which are difficult to measure - time inputs from personnel working within organizations on program development (drafting and reviewing policies, procedures and the like), training (most personnel will be trained), auditing (internal and maybe 3rd party) and very especially the pre-audit blitz that precedes most audits by 3rd parties.

Concerns about the value derived from implementing and certifying EMSs have not impacted growth in the field. Indeed there has been a significant uplift in the level of activity with the European Commission, EU Member State governments, US State and Federal government agencies joining with industry sector associations and others in the call to promote – and in many cases require - the uptake of management systems and third party certification of them.

US regulators in the state of Texas and other US states are offering meaningful incentives to organisations who meet a defined set of EMS requirements The American Chemistry Council is requiring all of their members to implement certified EMSs by the end of 2006. The US EPA has included requirements for 3rd party approved EMS’s in sentencing guidelines.

Those who are voicing concerns about the value of EMS point to an increasing body of anecdotal and empirical evidence which has found little or no correlation between certified EMSs and a variety of environmental performance metrics. The findings of these studies are surprising for many: the broad-based uptake of management systems in the environmental field was seen as a natural progression away from end-of-pipe thinking and most expected it to lead to significant operational efficiencies and other environmental performance gains.
Mature Field Development - A Review
Authors: Babadagli T.
Published: December 2007

Development of mature oil fields has been, and will increasingly be, an attractive subject. Mature field development practices can be divided into two major groups: (1) well engineering and (2) reservoir engineering. This paper focuses on the reservoir engineering aspects.

An extensive review of previously reported reservoir management practices for mature field development is provided. After the definition of mature field and an overview, different aspects of mature field development are outlined. The first issue covered is the estimation of remaining reserves focusing on the determination of the amount and location of the residual oil after primary and secondary recovery using field, log, and core data. After valuing the remaining oil, methods to recover it are classified. They include tertiary recovery, infill drilling, horizontals, optimal waterflooding design for mature fields, optimal well placement and other reservoir management practices. Suggested or implemented field application examples for big fields owned by majors and small fields owned by independents are presented.

Special attention is given to tertiary oil recovery. An extensive review and critical analysis of tertiary recovery techniques covering the theoretical, practical, and economical aspects of it are provided. The emphasis is on their applicability in mature field development in terms of effectiveness (incremental recovery) and efficiency (cost and recovery time). Laboratory and field scale applications of different tertiary recovery techniques, i.e., gas (double displacement, WAG, and miscible-immiscible HC, CO2, and N2), chemical (dilute surfactant, polymer, and micellar injection), and thermal (air and steam) injection, conducted to develop mature fields are included. Specific examples of big/giant fields, fields producing for decades, and mid to small size fields were selected. Differences in reservoir management strategies for majors, independents, and national oil companies are discussed.
Well-History-Based Prediction of Injectivity Decline (Accounting for Oil-Water Mobility Variation During Waterflooding)
Authors: Bedrikovetsky P. , Fonseca D. R. , Da Silva M. J. , Da Silva M. F. , Siqueira A. G. , de Souza A. L. S. , Furtado C.
Published: December 2007

Injectivity decline during sea/produced water injection is a wide spread phenomena in offshore and onshore waterflood projects. It happens due to capture of solid and liquid particles from the injected water by the rock resulting in permeability decline and also due to formation of low permeability external filter cake on the wellbore. Both phenomena result in injectivity impairment.

The field injectivity decline history is used for characterisation of the formation damage system and for the consequent well behaviour prediction.

The injectivity index increases M times during the damage-free displacement of oil by water (M is the water-oil mobility ratio). It affects the well injectivity prediction during poor quality water injection and changes the results of injectivity decline curve interpretation.

The combined effect of injectivity impairment by internal and external cakes and of the total oil-water mobility variation can be described by an analytical model. The model contains four injectivity damage parameters: the filtration and formation damage coefficients, the critical porosity ratio and the filter cake permeability.

The reliable modelling-based prediction of injectivity decline from a well injectivity index history requires knowledge of the four above-mentioned parameters.

In the current paper we develop a method for determination of the four injectivity damage parameters from the well injectivity history. Seventeen well data from eleven different oilfields have been treated, and the values of the four parameters lie in the same intervals as that obtained from laboratory tests. It validates the proposed method for injectivity decline system characterisation and allows recommending this method for prediction of injectivity decline from a well injectivity history.
Well-History-Based Prediction of Injectivity Decline During Seawater Flooding
Authors: Bedrikovetsky P. , da Silva M. J. , Fonseca D. R. , da Silva M. F. , Siqueira A. G. , de Souza A. L. S. , Furtado C.
Published: December 2007

Drastic loss of injectivity during waterflood using sea/produced water has been reported worldwide. It happens due to capture of solid and liquid particles from the injected water by the rock resulting in permeability decline, and also due to formation of low permeability cake on the wellbore. Both factors result in injectivity impairment.

Reliable prediction of injectivity decline should be based on mathematical modelling using coefficients that are well known for a specific well/field.

The mathematical model for injectivity damage contains four parameters: filtration and formation damage coefficients, critical porosity ratio and filter cake permeability. Nevertheless, just three constants can be extracted from two-piece-wise-linear injectivity decline curve.

In the current paper we propose the correlation between the formation damage coefficient and the critical porosity fraction to be used as a fourth equation allowing for characterization of injectivity damage system.

Eighteen well data have been treated, and values for four parameters of injectivity damage have been calculated. The obtained values have the same order of magnitude as those obtained from laboratory corefloods. It validates the proposal to use the correlation between the formation damage coefficient and the critical porosity fraction for characterisation of injectivity damage system from well history for the purpose of further prediction of well injectivity.
The Direct-Drive Variable-Speed Drive Head for PCPs Saves Big Bucks
Authors: Boyles G. A. , Stinson J. E.
Published: December 2007

Implementing a new configuration for the drive head for progressive cavity pumps can solve many operational problems and lower operational costs.Capable of handleing high sand loads keeps the pumps on and reduces downtime.Simplicity of design makes them easier and cheaper to build and maintain.Simple design of inline motor to a gear reducer coupled to the polish rod eliminates the problems and dangers associated with conventional belt and pulley configurations.When coupled with a power inverter the drive head speed can be reduced to 50% of capacity, allowing for quick pump saving adjustments.
Process Optimization Review
Authors: Pontiff M. E. , Boyer B. E.
Published: December 2007

This paper is a description of a method called Process Optimization Review (PRO-OP). PRO-OP is a systematic approach used in production operations to identify opportunities to increase profitability while reducing green house gases (GHGs) such as methane. PRO-OP is a systematic approach to assess processes at new and existing facilities with an emphasis on energy efficiency, natural resource conservation and waste minimization. The PRO-OP process uses proven methane reduction methods in the USEPA's Gas STAR Best Management Practices (BMP) to optimize the facility. This methodology can be used in conjunction with a Process Hazards Analysis (PHA) for new facilities and prior to modification of an existing facility.
Sealed Connector System Eliminates Explosive Hazards and Saves Time in the Make-up Operation for Tubing-Conveyed Perforating Gun Systems
Authors: Fimreite H. , Nordaas L. , Novak A. , Watson Roger
Published: December 2007

Proposal

When tubing-conveyed perforating (TCP)-guns have been needed, the traditional make-up method has been for the TCP and rig personnel to make them up manually using pipe wrenches on the rig floor. Efficiency in these efforts is critical to ensure a safe and reliable operation. When considering safety, this method is far from ideal since in an ideal situation, no personnel would be required to handle the explosive equipment on the rig floor while it is being assembled into the well.

A new system that considerably improves safety will be discussed in this paper. This new system, which encloses each end of the gun assembly, allows handling by the rig equipment and eliminates the need for human intervention. With these connectors, TCP-Gun assembly handling has improved safety, efficiency, and is compliant with the appropriate regulations.
Injection Testing To Determine Reservoir Properties
Authors: Goodman C. , Howell R. , Gabbard J.
Published: December 2007

In many locations, totally evaluating the quality of a reservoir based on conventional logs alone is difficult. This difficulty is especially present in lower-permeability reservoirs. Often, conventional logs can allow the operator to pass up zones that may be more productive than indicated on a conventional porosity cutoff. In such cases, a zone is perforated and allowed to flow to get a better evaluation of the zone and its production potential. However, if the zone does not flow to expectations, the operator may face a real dilemma: is it a poor-quality reservoir, or is some sort of damage prohibiting flow? This question can be very daunting and may not be easily answered, especially if the well will not flow adequately for a buildup analysis within a reasonable time frame.

In this paper, the potential for using a small injection test and the subsequent pressure fall-off to analyze the reservoir pressure and permeability is evaluated. Many benefits could be derived from using an injection test for reservoir analysis. Some are obvious, such as the capability to determine permeability and reservoir pressure, but this test can also be advantageous because these properties can be determined without flowing the well (which in some circumstances may be difficult and/or costly).

In this paper, a deep Atoka Wash well in Western Oklahoma is evaluated. The results of the fracture injection test are discussed, as well as how these results compare with a conventional buildup analysis.
Well Testing Best Practice
Authors: Zheng S.-Y. , Corbett P.
Published: December 2007

This paper will present study results from a ten-year long oil industry sponsored research project in this subject area. The survey of well testing practice covered situations from a range of major oil companies in China, Europe and Russia, which reflected problems that have long existed. These issues were further confirmed at the 2002 SPE well testing Forum. It was realised there is a need to promote best practice in the oil industry, and in well testing in particular, and that was the motivation for this paper.

Well testing, regarded as transient pressure testing, is usually very expensive. Bad testing data resulting from lack of design, preparation and unsupervised operation are really expensive. The contribution from the test to your asset is negative if a decision is made based on the information derived from non- representative data. Therefore, why not carefully prepare or design your test beforehand? There should be no excuse after spending two million dollars for a test and failing to deliver the information you expected. In our eleven years of research and teaching experience worldwide in the subject area, we found that well test interpretation engineers need skills other than in the subject itself in order to get more value from well testing. There is also a need to clarify the ambiguity in some well testing concepts such as data, information, analysis and interpretation, in order to develop a test procedure that is generally easy to follow and understand. In this paper, the study results will address all issues from justifying a test to the right procedures to conduct and interpret a test. The definition of a transient pressure test and a PI test, well test objectives and alternative measurements available to consider in the oil industry, as well as the advantages and disadvantages of these measures, are critically reviewed. We term this approach: Well Testing Best Practice (WTBP).