bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful System Integration Test of Real-Time Drillstem Test String for Deepwater Using Fully Acoustic Telemetry Monitoring and Control of the Well Across Electrohydraulic Subsea Disconnect Tool
Authors: Vo Thinh , Cao Duc , Choo Bryan
Published: February 2017

Depletion of shallow water oil reserves and growing energy demands have required exploration and development to extend into deepwater resources. Ever-changing environments in deepwater offshore locations present new challenges and require cutting-edge well-testing technology as well as advancements in cost optimization and operational safety.

This paper introduces a successful system integration test (SIT) in preparation for the first deepwater well test in Vietnam on a dynamic positioning vessel in 1117 m water depth for a 3764 m deep well. It was the first time both a real-time acoustic controlled well-testing system and an electrohydraulic (EH) controlled subsea safety system were to be deployed. The acoustically controlled well-testing system eliminated the use of electric lines to obtain real-time accurate reservoir information and minimized the use of annulus pressure to operate downhole tools. The EH-controlled subsea safety system introduced superior safety measures for emergency situations requiring less rig time.

The full system included the following: EH-controlled subsea safety system that uses the speed of EH actuation to perform emergency well shut-in and landing string secure disconnectAcoustically operated combined tester valve and circulating valveAcoustically triggered downhole samplersReal-time acquisition of reservoir pressure and temperature dataReal-time monitoring of downhole valve statusReal-time monitoring of seabed pressure and temperature data

During the SIT, the EH-controlled subsea safety system demonstrated an emergency shut-in including disconnecting the landing string in 8 seconds. Additionally, the acoustically controlled well-testing system demonstrated real-time acquisition of downhole pressure and temperature data, operated and monitored the status of downhole valves, and acoustically activated bottomhole samplers. Although the tool string was not deployed offshore because of dry holes, the success of the SIT validated the ability of this combined system to provide high performance, high safety levels, and high quality standards. This combined system would not only allow the operator to make immediate and accurate decisions to achieve intended well-test objectives, but also would provide effective safety measures in emergency situations in less rig time. The successful SIT should encourage exploration expansion in deepwater environments in the near future when solutions are available for additional challenges facing operators.
A Geomechanical Approach for Drilling Performance Optimization Across Shales in Safaniya Field—Arabian Gulf, Saudi Arabia
Authors: Alsahlawi Ziyad , Foster Herschel , Hussein Mohamed
Published: February 2017

Mud-weight selection is a critical factor for ensuring wellbore stability while drilling, especially in the presence of unstable shale formations. This paper describes a geomechanical approach that has been used to optimize the drilling of these types of wells. In an offshore field, the 12-¼-in. sections are typically drilled across well-known, unstable shale formations that have caused numerous stuck-pipe incidents and wellbore-related nonproductive time (NPT) in most of the offset wells. During the planning phase, the formation evaluation data, casing design, and directional profiles are reviewed and analyzed. These data are then used to perform a geomechanical study to identify the safe mud-weight window. The outcome of the study is then used to produce a set of guidelines for drilling these wells across the problematic 12-¼-in. section. These guidelines were applied to wells from an offshore field in Saudi Arabia in which the troublesome section was drilled to the casing point in each well, with no observed wellbore-stability issues. There were no losses induced and no formation collapse encountered. The planned reaming trips were eliminated, which significantly reduced the cost of drilling and completing these wells. Based on the outcome of this study and the results, this process, based on geomechanical analysis, can be used as a reference for optimal mud-weight selection to mitigate wellbore-stability problems in nearby platforms in this field of the Arabian Gulf.
The Evaluation of Micronized Barite As a Weighting Material for Completing HPHT Wells
Authors: Mohamed A. K. , Elkatatny S. A. , Mahmoud M. A. , Shawabkeh R. A. , Al-Majed A. A.
Published: February 2017

Barite is one of the most common weighting materials for drilling and completion fluids. Its good properties (high density, less environmental impact, and low production cost) outperform the other weighting materials and make it a good candidate for drilling and completing oil and gas wells. However, some problems were encountered in the industry while using solid particles to increase fluid density, solids invasion which causes formation damage and permeability reduction in the vicinity of the wellbore, and the tendency of these solid particles to settle therefore, the loss of well control is likely. Moreover, an erosion to the surface facilities will result when these solid particles are produced.

This study aims to investigate the effect of barite particle size on barite removal and completion fluids stability and how reducing barite particle size will help in resolving barite sag tendency and mitigating its effect. In this study, different samples of barite with different particle sizes were prepared using sieve analysis. Ball milling was used to reduce barite particle size to few microns. zeta potential and sag test were performed to evaluate the stability of micronized barite. Solubility test and high pressure high temperature filter press were used to study the effect of reducing barite particle size on barite removal.

Solubility tests showed a good enhancement in barite removal as the particle size was reduced, with a difference of around 11 g/L (20 wt.%) between the largest and the micronized size of barite. HPHT Filtration test results confirmed the solubility results with 5 wt.% enhancement in filter cake removal efficiency. Micronized barite showed a moderate stability with zeta potential measurements for a pH range greater than 8, while sag test showed insignificant enhancement in fluid stability as barite particle size was reduced to the micronized size.
Developing Home Grown Talent Operations' Manpower
Authors: Agawani Mamdouh M. , Abdalla Tamer S. , Almustafa Fadi Z. , Ho Kah Ming
Published: February 2017

Saudi Aramco's Drilling & Workover (D&WO) organizationsought to recruit competent Saudidrilling professionals to help implementits aggressive drilling operations plan. During the past few years, the D&WO organization was facing some difficulties attracting local professionals. In order to meet the national and global commitments, it became necessary to develop and retain additional Saudi drilling professionals to manage D&WO activities. This paper outlines how Saudi Aramco trains and develops local talent through its Rig Operations Program (ROP). This customizedprogram wasdeveloped internally by implementing mixed training methods. This strategyhelps to ensure the success of local talent entering the Saudi Aramco workforce. The Saudi Aramco D&WO Training Division has implemented this program to accelerate the development of recent Saudi engineering graduates. The goal is to prepare them to be world-class drilling engineers and drilling foremen. The ROP is unique in that it is developed and implemented by the Saudi Aramco D&WO Training Division in cooperation with drilling contractors. Multipletraining methods have been implemented to meet the objectives and requirements of each assignment throughout the three-year program duration.

The ROP includes world-class classroom learning, e-Learning, knowledge transfer and competency based training. Mentorship and on-the-job training is also incorporated. In addition, the latest drilling engineering software, well control simulators and training rigs are integrated into this development program. The ROP has gone through several revisions and improvements since 2011. Now it has a solid structure that includesa rigorous evaluation system. This ensures high competency levels of the participants graduating from the training program. Through extensive program evaluation, we have determined that mentoring and employing diverse training methods have dramatically aided the development of theemployees. These methods have helped them to quickly contribute to their organizations by handling their regular dutiesin a shorter period of time. This paperoutlines the structure of the program, and how it is implemented by the D&WO Training Division. Alsoincluded are the evaluation findings and methods for tracking the participants’ progress. In addition, measurement tools used to gauge the training program's success and major challenges are detailed. Lessons learned with recommendations stemming from the implementation and evaluation phases of the training program are discussed. Executing such a program is very costly in the short term. However, it provides a significant return on investment as talented Saudi professionals take over D&WO operations; thereby, reducing the need for expatriates. The ROP is an excellent example of how to quickly develop young drilling and workover foremen and engineers, and prepare them to professionally handle the complex tasks associated with D&WO operations.
Health, Safety and Environmental Performance System
Authors: Otaibi Mohammed S. , Divine Kyle W. , Qahtani Mohammad M.
Published: February 2017

"Protect your hands, you need them to pick up your pay check." The approach in this paper will not discuss the Health, Safety and Environmental (HSE) aspects directly; rather it will discuss HSE methodologies and deployment of software applications as well emerging technology utilized in collecting and analyzing data to improve HSE aspects within the drilling and workover field. Maslow's Hierarchy of Needs outlines two levels within its pyramid related to HSE, Fig. 1. Maslow's theory begins with physiological and safety levels and consisting of food, sleep, exertion, and security of body of health and of property.

Figure 1 Maslow's Hierarchy of Needs pyramid.

Within this context, HSE performance has to go through intensive processes to develop progressive HSE management programs, recommendations, key performance indicators (KPIs) and reports to improve the overall performance in an organization. Within the Drilling and Workover organization, HSE is a major operational KPI intended to:

Increase the transparency of incident reporting culture. Increase the awareness and culture of HSE in all workplaces. Open new opportunities to redesign and improve HSE aspects. Decrease incidents over time. Form several training programs for rig personnel.

Multiple HSE software applications have been introduced into the day-to-day business of all drilling operational activities. This software has served as the processing system where all HSE data flows to facilitate careful analysis of every aspect related to HSE within the organization to enable visualization of relevant HSE trends. This accumulated data consists of thousands upon thousands of records and is a combination of inspection findings, behavioral-based safety observations (unsafe acts and unsafe conditions), incident investigations, employee training and HSE systems, procedures and administrative controls.

The overall result is improved drilling and workover business intelligence in regards to overall HSE performance and improved confidence in management decisions related to contractor performance as well as improvements in HSE KPI performance. The record shows that over time many HSE incidents decreased in frequency. Thanks to the available data, our organization is positioning itself to begin recognizing specific incidents prior to their occurrence and to implement preventive measures to prevent the incidents manifestation.
The Application of Solid Inhibitor for Calcium Sulfate Scale Control Under High Pressure and Temperature Conditions
Authors: Shen Dong , Bhaduri Sumit , Vo Minh , Carman Paul , Gupta D. V. , Pandey Yash
Published: February 2017

Calcium sulfate is inherently a difficult mineral scale during oil and gas production process because the amount of scale formed is much greater than that of barium sulfate at similar scale saturation index level, and it is very difficult to clean up. This is especially challenging in conjunction with HTHP stimulation treatments where compatibility of the scale control chemical with fracturing fluids is critical, and when longer-term inhibition performance is desired. A new solid inhibitor was developed for this purpose and applied in multiple wells in the Krishna Godavari (KG) basin offshore India to combat mineral scale within the proppant pack and production tubing over the long term, under extreme downhole conditions (T= 400°F, P=13,500 psi). Normally, downhole chemical injection mandrels and surface treatments cannot adequately control scale deposition under these conditions.

The new solid inhibitor product was made by adsorbing scale inhibitor onto a high-strength, proppant-sized substrate with a large surface area. The high-strength substrate were prepared by sol-gel chemistry through hydrolysis of aluminum alkoxides and formation of particles that are calcined and then sintered at high temperatures to produce a substrate with the desired strength and surface area. The scale inhibitor used exhibited excellent inhibition performance and good compatibility with metal based cross-linked fracturing fluid systems at high temperature.

Tests performed with proppants/substrates show that using high loading of the substrates with the proppant does not damage the proppant pack even under very high stresses, For example, API crush tests of a mixture of 80% conventional untra-high strength proppant with 20% substrate by weight at 13,000 psi produced less than 4.7% fines and 88% of the produced fines were larger than 100 mesh and the fracture conductivity of the pack is maintained. The results of comprehensive laboratory testing show the new solid inhibitor can prevent anhydrite scale up to 400°F, and is completely compatible with zirconium- crosslinked fracturing fluid at 350°F and above. To date, six fracture treatments have been performed using a total 23,800 lbs of this new solid inhibitor. The wellhead water samples are being collected for scale inhibitor residuals analysis, as the wells start to produce water.

To ensure compatibility of the inhibitors with high-temperature fracturing fluids, especially metal based cross-linked fracturing fluids, without compromising the inhibition longevity at high pressure and temperature remains a stiff challenge, although adding scale inhibitors to a fracturing fluid has been a well-established practice to provide long-term inhibitor protection during hydrocarbon production. The new approach described here meets this objective, extending the long-term well performance under HTHP conditions.
Lab Study and Field Application of Surfactant Induced Imbibition for Low Permeability Reservoirs
Authors: Zhang Fan , Zhu Youyi , Luo Wenli , Cai Hongyan , Song Wenfeng , Zhang Qun , Zhou Zhaohui
Published: February 2017

Low permeability reservoirs are widely distributed in various countries, which contribute an important percentage of oil output in the world. At present the main exploitation mode is water flooding, but the oil recovery is very low. So it is very necessary to develop effective development technology. Chemical flooding technique is one of effective ways to enhanced oil recovery (EOR). However, low permeability may cause injection difficulty of conventional chemical agents (polymers and formulations of chemical combination flooding). Moreover, high temperature or high salinity condition may cause decomposition of the surfactant and polymer with poor long-term stability. For these harsh condition reservoirs, surfactant induced imbibition is an important and promising technology to enhance oil recovery. The key technology is to develop high efficiency surfactant with low cost. In this paper, the novel anionic surfactant has been developed with good capabilities, including good wettability alteration performance, low adsorptions, wide adaptability, good heat resistant and salt tolerant abilities, and high oil displacement efficiencies. Above all, the field test results are good in China.

The anionic surfactant could alter wettability from oil-wet to water-wet effectively and had good stripping film capacity. Contact angles were changed remarkably from more than 130° to less than 50°, and oil film could be peeled off in 180 seconds rapidly. The surfactant had good anti-adsorption ability, and it could maintain ultra-low interfacial tension for 5 times adsorption with the natural sand. The dynamic adsorptions of the anionic surfactant on the rock were less than 1.0 mg/g rock, which will meet the requirement of field applications. The anionic surfactant has wide adaptability and good heat resistant and salt tolerant capabilities. The maximum temperature was 160°C, and the maximum salinity was 220,000 mg/L. Core flooding tests demonstrated an average incremental recovery of 12.5% was achieved utilizing imbibition technology. For Qinghai oilfield (low permeability 26×10−3µm2, high temperature 126°C, high salinity 200,000 mg/L) in China, field pilot test of imbibition oil recovery technology was successful. 18 tons of imbibition agents were injected and increased oil production of 3660 tons.

Excellent properties of the anionic surfactant indicate that it is a promising surfactant, which can be applied in low permeability reservoirs, especially for high temperature and high salinity reservoirs.
Hole Cleaning and ECD Management for Drilling Ultra-Long-Reach Laterals
Authors: Zhang Feifei , Filippov Andrey , Miska Stefan , Yu Mengjiao
Published: February 2017

Insufficient hole cleaning in an ultra-long-reach lateral can increase the friction on the drillstring, which can lead to high torque and insufficient weight on bit (WOB). Cuttings affect the equivalent circulating density (ECD) in two ways: by increasing the average density of the drilling fluid and by reducing the open area left for fluid flow, as the cuttings tend to pack in the well and form cuttings beds. This paper presents the key findings regarding cuttings-bed development and ECD management for drilling an ultra-long-reach lateral.

Most of the previous cuttings-transport studies only focus on the cuttings-bed prediction in steady-state conditions. Few studies discuss the relationship between the cuttings bed and torque and drag and the effect of cuttings on the ECD. Furthermore, the flow in the wellbore is unsteady because of the frequent change of drilling parameters and wiper trips. In this study, a transient hole-cleaning simulator is used to simulate the cuttings-transport process in the wellbore. This simulator is also able to accurately calculate the ECD by considering the effects of both suspended cuttings and packed cuttings beds, or dunes.

The transient simulator is verified by conducting a series of tests using a 90-ft long, 8×4.5-in. drilling-simulation flow loop. Several commonly used rules of thumb for hole-cleaning practice in deviated wells are examined by running the simulator on a practical well. This paper presents new criteria for hole cleaning in deviated wells with ultra-long-reach laterals by considering the amount of cuttings in the wellbore and the requirements for ECD control. Recommendations for a set of hole-cleaning practices for drilling deviated wells with ultra-long-reach laterals will also be presented.

In addition to guiding drilling operations, the results of this work can be used to determine the maximum length for a horizontal lateral from an ECD management perspective. They can also be used to improve the torque-and-drag model for drillstring design in horizontal wells.
Offshore Drilling Operation Time Optimization Using PDC Bit Shearing Cap Technology
Authors: Al-Jamea Musab A. , Al-Saggaf Hatem M. , Boussahaba Hocine , Cuillier Bruno
Published: February 2017

For many years, Saudi Aramco has searched for a way to replace the practice of drilling out the DV’s and Shoe Track with a tricone bit, followed by a polycrystalline diamond cutter (PDC) bit to drill the new formation to the next casing point. Many bit manufacturers have conducted trials to overcome the challenge, with limited success. This paper discusses a successful, single-run technology to drill out and continue drilling using only a PDC bit.

Investigations of the root causes of failure and erratic performance led to extensive review of bit design and drilling practices, but fail to overcome the single-run challenge posed by cutter wear and damage experienced during the drill out.

Recently developed shear cap technology provides a means of installing high-grade tungsten carbide caps on the PDC cutters. The caps protect the cutters during the drill out, and then wear away to expose the cutters in pristine condition for drilling the formation.

The shear cap technology has been tested extensively and optimized using various bottom-hole assemblies. The result has been a considerable breakthrough in the success rate for drilling the formation section, accompanied by a time reduction that has resulted in huge savings in offshore oil drilling operations.

The standard PDC bits fitted with the protective technology are successfully providing a one-trip capability, saving a round trip to change the bit and achieving a 100% success rate in drilling to the next the casing point. When drilling in the casing, the tungsten carbide shearing caps are effectively mitigating the cutter damage typically experienced when drilling out the shoe track. Drilling performance in the formation and the ability to efficiently drill the full section, demonstrates the undamaged condition of the cutters when the bit exits the casing. Overcoming the longstanding efficiency challenge of drilling both shoe track and formation in a single run is being achieved with the novel technology’s ability to enable optimal formation drilling by protecting cutters during the shoe drill out.
A Semianalytical Approach to Estimate the Locations of Malfunctioning Horizontal Wellbore through Bottom-Hole Pressure and Its Application in Hudson Oilfield
Authors: He Youwei , Cheng Shiqing , Qin Jiazheng , Wang Yang , Feng Naichao , Hu Limin , Huang Yao , Fang Ran , Yu Haiyang
Published: February 2017

Some wellbore segments have little or no contribution to total production rates because of reservoir heterogeneity, completion methods, and nonuniform formation damage along the horizontal wellbore. This work presents a semianalytical approach to determine the effective producing length (EPL) and production distribution of horizontal well, and further estimate the locations of malfunctioning horizontal wellbore and the segments of water or gas coning through the history matching of bottomhole-pressure (BHP) data.

In this approach, horizontal wellbore was divided into multiple producing segments and each producing segment (PS) can be considered as a cylindrical source. New pressure-transient solutions are further developed for a horizontal well with multiple segments of arbitrary length, production, skin factor, and spacing. This work obtaines the type curves and further investigates the effect of crucial parameters (e.g. EPL, spacing between PS, number, production and skin factor of each PS) on pressure-transient behaviors. Results show that there are distinct differences among type curves with different parameters above. A horizontal line with the value of 0.5/N can be noticed in the pressure-derivative curve during the second radial-flow regime when inteferences between PS are minor. If the second radial-flow was misinterpreted as pseudoradial-flow, the interpreted permeability will be N times smaller than the accurate result. Therefore, it is significant to identify the horizontal line correctly especially for low-permeability reservoir (hard to reach the second radial-flow) and offshore oil fields (because of the short testing time). Finally, a history matching procedure is developed to determine the parameters above, and has been applied into two horizontal wells of Hudson oilfield in Tarim Basin. Case studies highlight the physical consistency of the solution, and demonstrate its practicability to estimate the EPL and diagnose the locations of malfunctioning horizontal wellbore.

The approach proposed in this work can be used to evaluate formation and well performance along horizontal wellbore so that engineers could make decisions on field strategies to improve well performance.
Extraction of Geological Information From Seismic Data Contaminated By Coherent Noise
Authors: Qin Fuhao , Tsingas Constantinos
Published: February 2017

Seismic data is often contaminated by coherent noise, such as surface waves and/or internal multiples. It is very difficult to suppress coherent noise that has very small slope differences from the true seismic events. We propose a procedure to reduce the coherency of the noise while retaining the coherency of the true seismic events on post-stack data so that random noise suppression technologies can be used.

The post-stack seismic events are first flattened using known primary events. Seismic traces are then randomly rearranged to destroy the coherency of the noise as guides. The rearrangement is limited to a predetermined spatial range in case of large spatial amplitude variations in the data. Seismic noise is then suppressed with random noise suppression technologies, such as median and fourier-wavenumber (FK) filtering. Seismic traces are then shifted back to their original locations.

Field data applications suggest that the proposed technique is effective and robust. It is very useful in obtaining an interpretable seismic seismic section from data heavily contaminated with hard-to-separate multiples and/or other coherent noise.
Integrated Multi-Disciplinary Forward Stratigraphic Modelling Workflow In Petroleum Systems Assessment
Authors: Hawie N. , Callies M. , Marfisi E.
Published: February 2017

With the continuous acquisition of worldwide multi-disciplinary datasets, geoscientists face the need for more integration. The combination of diverse expertise and multi-scale datasets has lately been supported by a fast rise in technological advances in data acquisition and processing (e.g., well logs, 3D seismic inversion and characterization) as well as by integrated 4D forward stratigraphic and basin modeling approaches. This work discusses the results of innovative methodologies developed in order to tackle rising challenges linked to the exploration of new hydrocarbon resources. The use of geomorphological, geological and geophysical constraints in process-based forward stratigraphic models shed light on the complex driving mechanisms that influence sediment transport and/or production and deposition along continuously evolving landscapes. The impact of subsidence rates, accommodation, climate evolution, drainage systems as well as eustatic variations on sedimentary bodies geometries and associated facies is investigated in various depositional settings (continental, transitional and marine). Lateral and vertical facies variations are consequently modelled taking into account the diversity of impacting environmental parameters. Coupled with petrophysical analysis as well as seismic inversion and characterization, this approach permits a 3D prediction of lithology, TOC and porosity distributions for the generation of integrated structural, facies and kerogen maps used in basin models in order to simulate the impact the architectural and thermal evolution on source rock burial, maturation, hydrocarbon generation, migration and trapping. These workflows set new grounds for the generation of Play Fairway Maps, Common Risk Maps for the different petroleum systems elements (reservoir, seal, trap and charge) as well as Composite Common Risk Maps permitting to produce innovative ideas and reflections around the exploration and production of hydrocarbon resources.
Ions Dependent Stability of Stearic Acid Langmuir Monolayers: An insight of Oil/Water Interface in SmartWater Flood
Authors: Gmira A. , Al Enezi S. M. , Yousef A. A.
Published: February 2017

SmartWater Flooding has been established as an effective recovery method in Carbonate Reservoirs by demonstrating a significant incremental oil recoveries in secondary and tertiary modes compared to seawater injection. The primary objective of this paper is to bring new microscopic insights on oil/water interface rheological properties and dependency of water ions, key constituents of SmartWater recipes and link it to a potential wettability alteration mechanisms. Stearic Acid (SA) monolayers were exposed to various individual ions, constituents of SmartWater recipes and surface pressures at oil/water interface were monitored using a Langmuir Trough. SA monolayers were studied under compression in presence of different key ions (Ca2+, Na+, SO42-, Mg2+) and salinity gradients. Parameters such, monolayer stability, phase transition and collapsing process will bring insight on the molecular organization and potential interactions between Stearic Acid and ions.

Surface pressure measurements confirm the sensitivity of oil/water interface to different ions present in the sub-phase and reveal a different behavior in presence of divalent ions (Calcium and Magnesium). Results show weak interactions at the interface between hydrocarbon chains and Sodium and Sulfate ions while dominant binding was observed in presence of divalent ions (Calcium and Magnesium). The measured Surface Pressure revealed a highly stable oil/water interface in presence of Calcium and Magnesium ions that can be attributed to a higher dissociation rate of hydrocarbon chains and possible bridging phenomena. Langmuir monolayer collapsing process is different in presence of divalent ions as it shows a steady increase of surface pressure after collapsing. This experimental study is tragetting oil/water interface and dependency to water ions, constituents of SmartWater recipes. The ultimate goal is to integrate fluid/fluid interactions and interfacial rheological properties with rock/fluid interactions knowledge to optimize water recipes for optimum oil recovery.
Critical Properties of Sand-Based Composite Aggregates for Sustainable Performance in Fracturing Applications
Authors: Nguyen Philip , Stephens Walter T. , Sanders Mike , Gashimov Ruslan , Al-Ghamdi Tawfik , AbdulRazzaq Waseem , Khalifa Mohamed
Published: February 2017

In the recent era of increasing oil and gas production, hydraulic fracturing is a proven economical technique to extract trapped hydrocarbons from tight reservoirs. A major factor associated with hydraulic fracturing is the significant quantity of proppant necessary and the high total contributing cost per well. For deep reservoirs, such as in the Middle East (ME), expensive, synthetic high-strength proppant (HSP) is necessary to withstand high closure stresses exceeding 15,000 psi. A new type of propping agent, a composite structure comprising low-performance sand from local sources in the ME, now exists that is capable of operating under these high closure stresses. Transforming low-performance sand into stable sand-based composite aggregates is a significant development, providing an abundant supply of low-cost propping agent that can enhance and sustain well productivity.

This paper demonstrates the sustainable performance of novel thin sheets of the sand-based composite aggregates under application conditions. Analyses of the performance measurements illustrate the unique and necessary properties these aggregates should exhibit to be successful in hydraulic fracturing.

Development of a new type of propping agent requires new techniques to measure performance. Most of these techniques apply common geophysical, chemical, and mechanical methods, while other techniques require considerable adaptation of traditional API testing methods. Performance of sand-based composite aggregates and synthetic HSP using these methods highlights the crucial and necessary aggregate properties.

Laboratory simulation of a post-fracturing scenario showed that low-performance sand, after conversion into sand-based composite aggregates, can withstand high closure stresses up to 10,000 psi. The measured conductivity of the channels is significantly higher than traditional synthetic proppant packs, and the aggregates are sufficiently strong to avoid fines generation. These observations indicate that sand can provide an effective alternative to HSP, which allows successful hydraulic fracturing in regions where synthetic proppants are cost prohibitive.

Finding an alternative to costly synthetic proppant has become more important in recent years. While the natural sand in the ME region is compositionally different and mechanically weaker than synthetic proppants and high-quality sands available in the USA, transforming the sand into composite structures provides unique performance properties. Because the sand is commercially abundant, this novel solution is a viable option.
A Modified Three-Point Contact Approach for Dogleg Severity Modeling
Authors: Gharib Hossam , Kirkhope Kennedy
Published: February 2017

A new approach was developed for modeling the dogleg severity (DLS) of curved wellbores during directional drilling. The approach is based on superimposing a modified three-point contact method with beam bending effects. The conventional three-point contact method provides a quick prediction of the DLS capability of mud motors. However, it is limited with respect to imposing a predetermined location of the three contact points and ignoring the weight on bit (WOB) and hole inclination effects. Moreover, hole enlargement is not considered in a three-point contact method, which can significantly influence the borehole curvature or DLS because of the change in stabilizer/borehole contact.

The new bottomhole assembly (BHA) contact/bending method presented in this paper involves a two-stage solution method. First, a modified three-point contact method is used that assumes a certain number and location of borehole contact points along the lower end of the BHA. This method calculates a preliminary value of the DLS without the loading effects. Subsequently, the effects resulting from WOB and hole inclination are considered to cause bending effects to the lower end of the BHA. These bending effects result in a change to the bend angle of the drill bit, which is used to correct the bend angle initially defined in the modified three-point contact method to obtain a final DLS solution. In addition, the hole enlargement attributable to the formation properties is considered to change the BHA-borehole contact points, thus influencing the achievable DLS range. This superposition approach, between the BHA-borehole contact and bending, results in DLS predictions for slick motors and stabilized directional drilling tools at various WOB and hole inclinations.

The contact-bending superposition (CBS) method is verified by using mud motor field survey data and is compared to the conventional three-point contact method. The CBS results show good correlation with field survey data. A greater rate of change in DLS is observed with slickbore assemblies, wherein the WOB and hole-inclination is more pronounced than stabilized assemblies. The CBS method and results demonstrate that a three-point contact approach with rigid BHA assumption is not sufficient to describe DLS. The bending effects are important considerations, particularly for assemblies with flex collars near the first stabilization point.

This new method provides a simple calculation of DLS for directional drilling tools. It is also useful when the time-consuming numerical models must be avoided, particularly at the conceptual design level, or when an efficient means of analyzing the DLS limitation of an existing tool is necessary.
Enabling Pore Pressure Prediction in Reservoirs by Replacing the Normal Compaction Trend by a Full Rock Physics Model
Authors: Debec Pascal
Published: February 2017

The ability to anticipate pressure in the reservoirs and shale is a critical point for safety and well control.

Shale compaction is mainly driven by effective stress. In "normal" (i.e. hydrostatic) pressure conditions, shale velocity is fortunately a "simple" function of effective stress: the Normal Compaction Trend (NCT). Many different methods exist for predicting shale Pore Pressure, in which velocity deviations from the NCT are directly attributed to stress variations and hence pore pressure variations.

Unfortunately, those approaches fail in case of facies, mineralogy or porosity changes (cementation, organic matter, smectite, sands, carbonates, etc.) since the NCT is only calibrated on shale. Pore pressure Prognosis in reservoirs classically has to be based upon other considerations, mostly made "by hand" (basin analogs, regional knowledge, reservoir size and connection to aquifer, etc.).

This paper presents a new approach predicting Pore Pressure in both shale and reservoirs. Replacing the NCT by a full RPM allows to take onboard petrophysical parameters (mineral fraction, porosity), and thus to estimate pressures in shales, but also in clastic reservoirs: Compressional Velocity (Vp) = f°(Pore Pressure, clay fraction, quartz fraction, calcite fraction, dolomite fraction,effective porosity…).
Evaluating the Performance of Advanced ESP Motor Technology in a Steam Assisted Gravity Drainage SAGD Field in Canada
Authors: Graham John , Coates Bryan , Montilla Carlos , Padilla Oscar
Published: February 2017

A significant percentage of all ESP failures are electrical failures and this becomes even more noteworthy in harsh, high temperature applications such as Steam Assisted Gravity Drainage (SAGD). For this reason, it is extremely important to continue the enhancement of ESP motor technologies that are specifically designed to address the challenging and unique SAGD environments that include wide bottom hole temperature ranges, abrasives and gas rich fluids. Through experience and testing, it has been learned that for these types of applications it imperative to design not only to a high temperature limit, but also to withstand extreme temperature cycles experienced on steam injection facility shutdown.

A combination of historic evidence with controlled laboratory evidence yielded improvement areas for a new high-temperature ESP motor development. The new high ultra-temperature motor breaks paradigms and opens a new generation of motors that looks towards above 300°C downhole temperatures. This paper will review the performance of the motor at Suncor's Firebag SAGD field where 92 units have been installed since January 2015 in bottom hole (BHT) temperatures reaching 240°C. Description of the laboratory qualification, major design characteristics and field results will also be discussed on the paper.
Implementing a Scientific Perspective and a Pragmatic Approach to Optimizing Perforated Completions
Authors: Zuklic Stephen , Satti Rajani , Myers William , Bale Derek , Sampson Tim
Published: February 2017

A truly optimized completion requires a wide range of understanding and activities. Starting with a thorough understanding of the reservoir, each completion element must be fully addressed from connecting to the reservoir, to enhancing the reservoir through proper treatments, to conducting hydrocarbons to surface for optimal efficiency. By considering the cause-and-effect interactions between these activities, each individual process can be designed and performed better, ultimately delivering the best overall solution. This overarching philosophy is also fully applicable to perforated completions.

Providing a perforating solution that is truly optimized for the reservoir is challenging, requiring advanced laboratory testing capabilities, reservoir specific products and systems, robust analysis and modeling tools, and a thorough process to insure solutions are designed, executed, and reviewed for continuous improvement and optimization. Recent advances in in-situ perforation testing techniques provide significant insights into dynamic events during perforating as well as enabling more reservoir specific equipment designs. Furthermore, state-of-the-art computational models complement testing methods by correlating dynamic perforating events and inflow analysis to actual productivity. Numeric modeling techniques also allow results from lab testing to be better translated into field scale environments. And finally, rigorous procedures can be followed to practice this process across a wide variety of completion types to provide well optimized perforated completions.

This study will detail the techniques used to employ the philosophy, and multiple case histories of such applications with results and lessons learned. In these cases, a comprehensive consideration of the overall completion was critical in optimizing the perforating process. The use of laboratory testing, customized products and systems, integrated modeling and analysis tools, and a disciplined process have led to the successful application of this scientifically engineered philosophy. This unique perforating philosophy is also aimed towards integration with other completion methods like hydraulic fracturing & stimulation, sand control and management and above all, enhancing reservoir productivity.
Beginning With the End In Mind: Shaped Charges Designed for Reservoir Conditions
Authors: Satti Rajani , Betancourt David , Harvey William , Zuklic Stephen , White Ryan , Ochsner Darren , Sampson Tim , Myers William , Gilliat Jim
Published: February 2017

Historically, the performance of shaped charge jet perforators has been evaluated using concrete targets under ambient conditions, thereby failing to clearly characterize their performance in downhole conditions. In recent years, testing using sandstone targets (API RP-19B Section 2) and various numerical models have been adopted as a better means of quantifying shaped charge performance. However, it is important to note that such testing and modeling methods do not still account for the complex shaped charge physics in downhole conditions, which includes pressures (wellbore to pore to confining), rock properties (bedding plane orientations, porosity, permeability, UCS, etc.), cement and casing material characteristics, etc. In fact, the results from standard tests or numerical models have been proven to be misleading while designing and optimizing shaped charges for reservoir conditions.

As a result, the advent of perforation flow laboratories and advances in shaped charge research and engineering has been the key motivation for this work. In this work, we have employed a scientifically engineered approach to determine and optimize shaped charge performance. A comprehensive test program in conjunction with computational modeling was utilized to design, test and improve shaped charge performance under reservoir-specific conditions. For this purpose, methods relating to API RP-19B Section 4 testing and advanced hydrodynamic solvers were integrated into a scientific workflow.

The results from this study demonstrate the following: First, pore pressure does influence shaped charge performance. Second, the best way to characterize the performance of a shaped charge is to conduct a laboratory test under true reservoir conditions. Third, designing a shaped charge around performance at true downhole conditions has enabled significant performance and productivity improvements.

Utilizing advanced numerical modeling and extensive testing, we have achieved significant increase in shaped charge performance (penetration and flow area) in some of the most challenging reservoir conditions. The new class of reservoir-driven shaped charges is aimed towards increasing production or injection by deeper formation connectivity with the wellbore as well as ensuring perforation contribution efficiency.
Surfactant-Polymer Flooding: Chemical Formulation Design and Evaluation for the Raudhatain Lower Burgan RALB Reservoir in Kuwait
Authors: Al-Murayri M.T. , Hassan A.A. , AlAbdullah M.B. , Abdulrahim A.M. , Marliere C. , Hocine S. , Tabary R.
Published: February 2017

Surfactant-Polymer (SP) flooding is an Enhanced Oil Recovery (EOR) process that can lead to incremental oil recovery through two mechanisms: reducing oil/water interfacial tension (IFT) to decrease residual oil saturation and increasing the viscosity of the displacing fluid to improve overall sweep efficiency. IFT reduction allows better oil recovery by overcoming capillary effects while the increased viscosity of the displacing fluid allows a more homogeneous sweep of reservoir oil. Implementing chemical flooding in reservoirs with relatively high temperature and in-situ salinity (> 200 g/L) is somewhat challenging. This paper describes the extensive laboratory work performed for the light oil Raudhatain Lower Burgan (RALB) reservoir (180°F/82°C) in Kuwait.

Reservoir fluids were thoroughly characterized to preselect the most suitable chemicals for the SP process. Reservoir crude oil was analyzed and recombined with gases (C1-C3) based on reported Gas-to-Oil (GOR) ratio to reproduce the oil in-place at original reservoir conditions in terms of pressure, temperature and oil composition. A shift of the live oil Equivalent Alkane Carbon Number (EACN) was noticed compared to dead oil EACN.

Numerous surfactants were screened based on three main criteria: solubility in the envisioned injection brine, ultra-low oil/water interfacial tension and chemical adsorption on reservoir rock. Different brine types were considered and the use of adsorption inhibitors was also investigated. Furthermore, polymer screening, involving temperature resistant polymers, was conducted by means of viscosity, long-term aging and adsorption tests. Polymer compatibility with the selected surfactants was also evaluated. The selected SP formulation was further evaluated through a series of coreflood experiments mainly based on chemical adsorption on reservoir rock and incremental oil recovery and an injection strategy was designed thereof.

Laboratory results obtained thus far are encouraging and provide a systematic methodology to design surfactant-polymer injection in high temperature, high salinity and light oil reservoirs that are similar to the RALB reservoir. Additional techno-economic evaluation is in progress in preparation for field-scale deployment of surfactant polymer injection at the RALB reservoir in Kuwait.