bluuebunny/crossref_metadata_2025 huggingface dataset:
A Case Study of Energy Storage Stimulation for Ultra-Low Permeability Oil Reservoir
Authors: Liu Wei , Zhang Kai , Jiang Tao , Yu LiMin , Bao ZhiDong , Lv Jiateng
Published: March 2017

The Tight oil reservoir has the characteristic of low porosity (average of 8%), ultra-low permeability (average of 0.1 mD), low abundance and high clay content. The conventional fracturing techniques in exploration area was not successful in some cases, a novel series of horizontal well energy-storage fracturing techniques is proposed to improve the conventional fracturing technique, which based on increasing modified volume and replenishing formation energy. This technology involves in spacing optimization along the horizontal well section, optimization of fracturing fluid parameter, and forming complex network cracks. Afterwards, well shut-in can store energy and contribute to oil/water replacement. A total of 6 horizontal wells with 73 sections were tested in the field with successfully oil testing up to 95% after the techniques, which produces a good industrial oil flow. Furthermore, the single-well production can approach 8-10 times higher than that from the straight wells and 2-3 times higher than that from other horizontal wells in the same well block. The energy-storage fracturing technique provides a technical support for prospection and development of tight oil reservoir.
Optimization of Hydraulic Fracture Development and Well Performance Using Limited Entry Perforations
Authors: Huang Jixiang , Datta-Gupta Akhil , Augustine Jody R.
Published: March 2017

Production logs from horizontal wells in shale reservoirs indicate that more than 30% of the perforation clusters do not contribute to production. One major reason is recognized as the stress shadow effect which impedes the propagation of the interior fractures within a single fracture stage. Although limited entry perforations have been successfully introduced in horizontal wells to counteract this completion inefficiency, the complex mechanisms involved have not been fully understood.

In this paper, a fully integrated workflow that incorporates fracture propagation, reservoir flow and wellbore hydraulics has been developed to evaluate the efficiency of limited entry perforations during multiple simultaneous fracture propagation. Darcy–Weisbach and classic orifice flow equations are adopted to describe the wellbore and perforation friction. The coupled reservoir and geomechanics model are solved by finite element code while a cohesive zone model, which accounts for the significant non-linear effects near fracture tip over the conventional linear elastic fracture mechanics, is used to simulate the fracturing process.

During the stimulation of multiple fractures, uneven fluid distribution will be observed once the fractures begin to interfere with each other. Meantime, the difference in perforation pressure loss due to uneven fluid rates will counteract the stress shadow effects and balance fluid distribution. Thus, a larger perforation friction coefficient is favorable but it also causes higher pumping pressure. A novel proppant model is proposed to represent both stress- and time-dependent fracture conductivity change due to proppant degradation in subsequent long-term production. Production simulation results demonstrate that deliberate deployment of limited entry technique can significantly increase production but this benefit is reduced with increased cluster spacing. Sensitivity study indicates that better well performance could be obtained by reducing number of shots in each cluster and increasing number of clusters in each stage. Non-uniform perforation shots distribution is proven to be an effective means to counteract the stress shadow effects while the cluster length is unchanged. Simulation results also indicate how the heterogeneity in reservoir properties affects the performance of limited entry perforations.

The proposed workflow has the advantage to integrate fracturing and production simulation in the same grid system and evaluate performance of different stimulation strategies. The comparison studies can provide critical insights to the application of engineered limited entry.
Applying Enhanced Cyclic Diversion Process in Granite Wash Open Annulus Horizontal Completion
Authors: Sullivan Lonnie , Grieser Bill
Published: March 2017

This paper describes methods to alter the flow path in the open annulus section of a horizontal Granite Wash stimulation completion. The challenge was to complete a 1,600-ft open annulus section using standard plug and perf (P&P) stimulation methods. The objective was to isolate and initiate individual fractures at each stage in an open annulus environment.

Altering the flow of proppant and fluid in the open annulus and near wellbore (NWB) involved multiple products, and procedures. This included cyclic application of the following:

Pump rates and intra stage shut-ins. Fluid types and viscosity-alteration (friction reducer and crosslinker). Proppant slurry and clean fluid sweep stages. Solid diverters. Chemical surface modification agents (SMAs) and resin-coated proppant (RCP).

The objectives were to cycle the bottomhole treating pressure (BHTP) and alter the flow path in the wellbore, annulus, NWB, and far field, while maintaining annulus and casing integrity.

A cyclic but continuous bottomhole pressure (BHP) increase was observed throughout the four stimulation stages pumped in the open annulus section. The surface pressure characteristic signature changed after each shut-in. Perforation operations in the open annulus sections above a completed stage did not indicate proppant inflow through the new perforations. The drill out of plugs in the open annulus section circulated trace amounts of untreated proppant. Initial flow back operations showed minimal proppant flowing to surface. Strong production results indicate contribution from 40% of the lateral section that had no annular isolation. Normalized production is compared to adjacent offset.

Our use of an enhanced cyclic diversion process (ECDP) was a success. Instead of using a single product or process; we used a cyclic combination of solid diverters, proppant coatings, prop/sweep stages, and shut-ins to deliver a variable BHTP and altered flow paths.
PTA Powder Hardbanding Provides Cost Savings and Extends Life of Drill Pipes in Permian Basin Formations
Authors: Omojuwa Emmanuel , Acquaye James , Hart Jamie , Okoye Ekene
Published: March 2017

PTA (Plasma Transferred Arc) powder hardbanding was developed to provide cost savings and extend drill pipe life over wire hardbanding especially in highly abrasive formations. PTA powder hardbanding is a metallurgical bonding (welding) process of depositing powdered hardfacing alloys onto magnetic & nonmagnetic drill pipe tool joints, collars and heavy weight drill pipes to protect both casing and drill string assets from abrasive wear. The process involves the application of a constricted high energy plasma arc between a powder alloy and the base material, creating a molten weld pool. This paper presents the operational and cost benefits from the utilization of PTA powder hardbanding. The high energy heat during welding is localized which minimizes the heat affected zone (HAZ), thus retaining mechanical properties in the base metal. PTA powder hardbanding process produces an overlay that has high bonding and overlay with better mechanical wear and corrosion properties than wire hardbanding process. Additional benefits of PTA powder hardbanding over conventional wire hardbanding include: controlled heat inputs with parameter optimization, low dilution of powdered alloy into the base material, uniform weld microstructure & smoother surface and lesser amounts of steel is lost after hardband wear.

PTA powder hardbanding reapplication is dependent on wear and cracking of existing hardband. PTA powder can be reapplied on wire hardbands and vice versa. PTA powder hardband was subjected to casing wear test according to API 7CW standard. Results from the casing wear test proved that the PTA powder hardband is a better casing friendly hardband compared to wire hardbands based on the casing wear percentage, mass lost, contact pressure threshold and tool joint wear in open hole. Field results from an operator in the Delaware Basin, New Mexico show a higher frequency of wire hardbanding reapplication (average of 1 joint every 2 wells) while PTA power hardbanded pipes show lower frequency of reapplication (average of 1 joint every 6 wells).
Geopolymer Cements: How Can You Plug and Abandon a Well with New Class of Cheap Efficient Sealing Materials
Authors: Salehi Saeed , Ezeakacha Chinedum Peter , Khattak M. J.
Published: March 2017

Plug and Abandonment, P&A, operation is inevitable for each and every well. Most oil and gas wells are plugged at lowest cost possible complying with requirements set by regulatory agencies. Geopolymers can be used as an alternative material for P&A operations. Unlike many other alternatives such as resin, they are cost efficient and easy to pump down the wellbore. They can be mixed easily onsite and activated by addition of an alkali activator. The research presented in this paper shows they can have a good pumpability, low shrinkage, and high compressive and shear bond strength.

The Geopolymer mixtures in this work were composed of Class F Fly Ash rich in Silicate and Aluminum, with elements of Potassium, Calcium, Iron, Sodium, and Titanium. A mixture of Sodium Hydroxide and Sodium Silicate was used to activate the Fly Ash mixtures. Geopolymer mixture designs tested in this work showed high compressive strength, low shrinkage, and suitable thickening time for applications in well abandonment. In addition, these alternative P&A materials can be produced cheaper with less environmental impact, which is a proper fit in the applications oil and gas well cementing.
Using Type Wells to Economically Schedule DUC Well Completions
Authors: Dash T. , Scott D. W. , Kwok C. K.
Published: March 2017

In response to the low hydrocarbon price environment, most operators have decreased the number of rigs actively drilling wells (Cui 2016, Chapman et al. 2016). However, the production decline in wells completed in a given timeframe has undergone far more change than the count of active rigs. In many cases, wells must be drilled to meet contractual lease obligations but are not being completed due to uncertain economic conditions.

Type curves are valuable tools to predict future performance of such drilled-but-uncompleted (DUC) wells by analyzing results of existing wells exhibiting similar characteristics. It is reasonable to assume, while considering reservoir characterization and completion engineering, that existing wells can predict the performance of future wells. However, to generate a larger sample size with which to construct the type curves, data can be normalized by a particular variable. A normalized curve is then scaled by an adjustment associated with the new well to produce its expected production profile. This same process also allows type curves to be applied to other areas with different reservoir properties or completion parameters. Analysis focuses on applying normalized type curves to estimate DUC well performance and populate a ranking system to guide the completion planning process. Reservoir material balance and surface network simulation are also utilized to understand subsurface effects and identify possible facility constraints above ground. Additionally, there is a brief discussion regarding type well best practices to aid in the analysis.
Low-Solids-Shear Dependent Cement System Eliminates Loss Circulation in the Upper Spraberry Formation in the Permian Basin: A Case History
Authors: Duffy Marcus , Hernández Olvin , Rojo Gustavo
Published: March 2017

Lost circulation is a recurring challenge and high-cost event within the oil industry, particularly in depleted or weak fracture-gradient zones. Lost circulation can significantly increase operational costs, nonproductive time (NPT), the possibility of stuck pipe, and, in some cases, can result in well loss.

Lost circulation can be defined in a variety of ways, ranging from partial to total losses in a variety of formations, including highly permeable, fractured, or cavernous formations. In cases of total losses, conventional lost circulation material (LCM), such as gel-based and large-particulate-laden fluid, can be ineffective when it is unable to isolate the flow zones.

The fluid system discussed in this paper uses a low-solids shear dependent cement (LSSDC) system that will remain fluid until the system begins to lose shear rate to remediate loss circulation. As the fluid system enters the loss zones and the shear rate is reduced, rapid gel strength development occurs. The cement system will become pumpable again, for a few cycles, if shear is reapplied within a specified time frame. After the shear rate has been sufficiently reduced to enable the gel strength to develop, rapid compressive strength development ensues. This development enables the isolation of cavernous or vugular formations that could have partial or total losses. The rapid compressive strength development enables drilling to proceed within a relatively short amount of time as the hydrated cement is capable of withstanding circulation pressure.

Drilling through the Upper Spraberry formation, located between 6,500 and 8,500 ft in the Permian basin, represents a drilling challenge because of lost circulation difficulties. Traditional treatments to reduce the lost circulation issues include cement plug operations and mud sweeps with LCM, but none have established a consistent lost circulation resolution. For this case, the producing company prepared 100 bbl of mud sweep containing fibers, mica, and nut fines as LCM. However, total losses continued with no improvement as the LCM sweep was pumped. A total of 42 bbl of the LSSDC was then pumped; operations proceeded successfully, and the well was drilled with no other lost circulation problems. The fluid system presented remediates lost circulation through a mechanism that, unlike any fluid system within the oil industry, develops rapid compressive strengths after it is placed to withstand circulation pressures and to enable drilling to continue.
Experimental Study and Pilot Test of Combined Gel Treatment and Surfactant Imbibition Technology in High Temperature, High Salinity Reservoir
Authors: Hongyan Cai , Wenli Luo , Desheng Ma , Xinyu Zhou , Jian Fan , Jianguo Li , Jianfeng Sun , Yi Zhang
Published: March 2017

With the depletion of petroleum resources, EOR in marginal oilfields attracts more and more concern worldwide. For high temperature, high salinity (HTHS) reservoirs, CEOR shows promising potential while faces great challenge due to adverse effects on chemicals by severe reservoir conditions. Curling, thermal degradation, and breakdown of molecular segment caused by HTHS makes polymer an unsatisfactory candidate. How to effectively improve mobility control and achieve high recovery becomes one of the key issues in CEOR of HTHS reservoirs. Herein, a CEOR method combining gel treatment and surfactant imbibition was put forward and evaluated for a HTHS reservoir with reservoir temperature 126 °C, injection brine salinity 117,000 mg/L, and divalent ion content 3,340 mg/L. Gel formulation was optimized to suit application requirement. Tests on solubility, thermal stability at HTHS conditions, and spontaneous imbibition were performed for several surfactants to obtain suitable chemical agent for target reservoir. An organic crosslinker was added to the diluted solution of a heat tolerant, salt resistant Star-shape polymer to form flowing gel. Evaluation results showed the viscosity of gel reached 43,900 mPa·s at 5th day and standed at 43,500 mPa·s after 180 day aging, demonstrating good thermal stability. An anion-nonionic surfactant showed good compatibility with brine, acceptable thermal stability at HTHS, and sound spontaneous imbibition recovery. One injector three producer pilot test was conducted employing the gel plus surfactant formulation and an incremental oil production of 3660 MT was accomplished. In-lab evaluation and pilot test displayed inspiring result of gel with surfactant imbibition technology, which provides a good option for CEOR of HTHS reservoirs.
Innovating in the Oil and Gas Industry: A Framework for Aligning Innovation Strategy and Tactics
Authors: Redden James E. , Strickland Cary T.
Published: March 2017

The decline in oil prices in 2015 and 2016 has forced innovation managers within the oil and gas industry to do more with smaller budgets. To meet this challenge, oil and gas companies in the United States need to optimize their innovation investment. By interviewing experts across the industry, we have identified six common innovation behaviors. Explicitly aligning these behaviors with innovation strategy can help oil and gas companies spend limited innovation dollars wisely. To help guide decision making, we developed three innovation archetypes (reactive, opportunistic, and proactive) that describe the relative emphasis that various companies place on different innovation behaviors. Reactive innovators limit their investment in innovation activities but forgo some of the competitive advantage offered by new technology. Opportunistic innovators keep pace with new technology but have relatively little control over developing innovations. Proactive innovators help shape technology development to derive maximum value from the innovations developed. Innovation managers can use the framework in this paper to assess their portfolio of activities holistically, or they can apply these archetypes to specific technology domains (e.g., big data or oilfield chemicals). This new framework can help align tactics with strategy to maximize innovation outcomes while oil prices remain low.
Interrelating Production Analysis with Pore Scale Structure in the Bakken Reservoir
Authors: Grella M. A. , Callard J.
Published: March 2017

Conventional laboratory methods for obtaining relative permeability in oil and gas shales are difficult if even possible to obtain. Insight can be gained from high pressure mercury injection and the relative permeability obtained there from using pore throat models. An integrated approach between relative permeability derived from core laboratory pore throat models with production analysis allowed us to generate new type curves that can be used with field production to determine Brooks Corey wetting phase exponents.

A procedure utilizing laboratory mercury injection capillary pressure on core samples from the Bakken reservoir is used to generate a distribution of wetting phase saturation exponents and residual wetting phase saturations for numerical simulation model input. Model output is normalized by the time and cumulative oil production at the onset of boundary dominated flow to generate type curves that can be used to successfully history match field production in the Bakken formation in North Dakota.

A new type curve has been developed in which oil production and transition from linear to boundary dominated flow are the two requirements needed to derive oil-gas relative permeability. The median of wetting phase saturation exponents for the Middle Bakken formation ranges between values of 2.3-2.6.

Other useful results from the combination numerical simulation and field production data study include the prediction and observation of an elevated yet constant producing gas oil ratio during the linear flow period (prior to boundary dominated flow.) Several consequences of this result allows selection of proper application of decline curve analysis techniques, properly determine initial solution gas oil ratio for fluid characterization, and indication of relative permeability prior to the onset of boundary dominated data.
Prediction Model for Gas Migration in Well During PMCD Operation
Authors: Terra Felipe de , Lage Antonio Carlos , Fjelde Kjell Kåre , Naccache Mônica Feijó , Stuckenbruck Sidney
Published: March 2017

The use of the Managed Pressure Drilling (MPD) is spreading in offshore operations. The increasing complexity in the new exploratory frontiers is demanding for new techniques to reduce costs and increase operational safety. MPD appears as an answer for that demand and sometimes it is the only viable way to drill some of the challenging wells. In that way, understanding the gas migration behavior while drilling in PMCD mode allows an optimized well design concerning cost and operational safety.

The present study validates a mathematical model capable of simulating a scenario where loss of drilling fluid in the bottom of the well is present while having an influx from the same reservoir and observing gas migration to the surface in a PMCD operation. A Drift Flux Two Phase Flow Model is used in association with the Advection Upstream Splitting Method (AUSMV). Before the presentation and discussion of the complete PMCD scenario, two simple cases were simulated and the results were compared to the ones from a computer application considered as a reference to the industry, validating the proposed model. The results of the simulations can be used as a base for the elaboration of operational procedures to monitor gas behavior and optimize bullhead in PMCD scenarios.
Lessons Learned in Drilling Fluids Projects during MPD and MCD Operations in Brazil's Offshore Wells
Authors: Teixeira G. T. , Fabri F. , de Almeida L. S. , da Silva P. H. , Vadinal R. B.
Published: March 2017

Drilling fluids play great importance to the success of MPD (Managed Pressure Drilling) and MCD (Mud Cap Drilling) operations. On MPD projects, the correct design of the drilling fluids properties, such as, density, rheology, anchor point position and compatibility should be precisely adjusted in order to operate in good and safe performance, especially in a statically underbalance MPD projects. Exceptional importance should be addressed to the initial mud density to provide useful capacity to carry out a Dynamic Porous Pressure Test (DPPT).

MCD operations require a suitable drilling fluid project due gas migrations, costs and cuttings transportation issues, related to LAM (light annular mud) and sacrificial (SAC) fluids.

The objective of this paper is to present the lessons learned in drilling fluid projects during MPD and MCD operations in Brazil's offshore wells. The study will focus on desired properties, simulations, adjusted hydraulics models, formulations and involved costs, considering water and olefin based drilling fluids.
Overview of Different Applications for MPD and MCD Techniques on Deepwater Wells
Authors: Fernandes André Alonso , Tomita Reinaldo Akio , Junior Antonio Carlos , Abdu João Paulo , Vanni Guilherme Siqueira , Grandi Ricardo Freire , Longo Fabio Leonardo , Machado Giovani Ferreira , Agostini Cristiano Eduardo , Vadinal Rodolfo Balthazar , Silva Luiz Felipe
Published: March 2017

MPD is a very powerful tool that is gaining momentum for deepwater offshore wells construction. A dynamic positioning rig adapted to MPD operations can apply different techniques that better suit to each well scenario. Currently Petrobras has over 20 MPD deepwater offshore wells drilled, having applied different techniques to achieve success: from "basic" SBP to MCD variants. This paper discusses the various MPD techniques that can be utilized from a dynamic position rig during deepwater well construction.
Managed Pressure Drilling Flexible Mud Return Line Advances
Authors: Szekely Gergely , Peixoto Eduardo , Czovek Zuzana , Mezo Tamas
Published: March 2017

In the oil and gas industry there is a common misconception that bonded flexible pipes designed according to the only approved standard for deepwater MPD applications, API 17K are overdesigned and heavy.

This paper is to clarify the misconception and present to the industry the flexibility that API 17K gives to tailor the hose construction reflecting the actual requirements and customer needs. Over the last few years a lot has been learned on the MPD operations, using inputs of the industry's major players, the hose requirements that in the past led to overdesigned, heavy and expensive flexibles have been revised, allowing a more efficient hose construction to be developed keeping the design premises of API 17K. This newly developed MPD mud return line construction assures a significantly lighter and easier to handle hose while not compromising on HSE and quality.

Brief overview on API specifications is given in terms of their applicability to MPD operations. Technical challenges and solutions are discussed in details for the flexible pipes carrying well effluents in kick situations with special emphasis on technological advances resulting meaningful weight and cost savings. Results of the full scale tests demonstrating the hose performance are presented, such as bending stiffness test, blistering test and burst test.
Strategic Evaluation of MPD Application on DP Rigs
Authors: Aranha Pedro Esteves , Fernandes André Alonso , Vanni Guilherme Siqueira , Terra Felipe de , Tomita Reinaldo Akio , Tolfo Marcos Coradini , Gozzi Danilo Signorini
Published: March 2017

In recent years, PETROBRAS has been using MPD (SBP/MCD) technology in ultradeepwater scenarios at development and exploratory wells. Although MPD techniques are an advance over conventional drilling, it also brings more complexity to the operation and, in some cases, increases the duration and costs of the interventions when compared to conventional drilling.

Ideally, the rigs equipped with MPD system should only be used in wells, or in specific phases of the well, that requires MPD to conclude or where the NPT associated with fluid losses is considerable. In these scenarios, the extra costs and extra time necessary are negligible, compared to the NPT avoided, and the alternative would be not to reach target depth or drill the well.

Geomechanics, pore pressure estimation and loss zone identification are not an exact science. There is always an uncertainty in predicting MPD (SBP/MCD) demand, pushing the development of techniques and strategies to optimize the allocation of MPD rigs in wells where the NPT would be so high that the use of the MPD is advantageous, or, where MPD is an enabler of well construction.

This paper describes a probabilistic analysis developed to support the determination of MPD (SBP/MCD) demand, calculating the optimum number of rigs to be equipped with MPD (SBP/MCD) and RCD system, and which intervention strategy is the most cost effective for a development campaign, based on historic results.
Lessons Learned from MPD Operations with Underbalanced Drilling Fluid on Two Challenging HTHP Exploration Wells
Authors: Fredriksen Ragnar Marcelius , Bjerkås Johnny
Published: March 2017

The 2/4-22 S Romeo and the 2/4-23 S Julius exploration wells were drilled on the Norwegian continental shelf in 2014-2015, with a jack-up rig, utilizing Managed Pressure Drilling (MPD) and a hydrostatically underbalanced mud column. Both were High Pressure High Temperature (HPHT) wells with an expected Total Depth (TD) of 5500 m true vertical depth (TVD), expected reservoir pressures up to 2.14 SG and expected temperatures of 185 °C.

The 2/4 block is known for its challenging pressure and temperature regimes, and the underground blowout that occurred on the 2/4-14 well in 1989. The 2/4-21 King Lear well was drilled on the same structure as the 2/4-14 in 2012. Wellbore breathing, in combination with having a smaller drilling window than prognosed, caused drilling difficulties and endangered the likelihood of reaching TD and achieving the objectives of the well. For the two next well in the area, it was decided to utilize MPD to mitigate the expected drilling issues.

Both the 2/4-22 S Romeo and the 2/4-23 S Julius well encountered challenging drilling conditions that caused narrow drilling windows and the MPD technology was key for achieving the objectives for both wells. However, a serious well control incident occurred drilling the second well, when several barriers failed, following a sensor failure on the MPD equipment.

The purpose of the paper is to describe how the MPD operations were planned and executed, with focus on lessons learned.
A Mid-Riser Pump System Optimized for Rapid Deployment on Any Semisubmersible or Drillship
Authors: Piccolo Brian , Johnson Austin , Macgregor Alex , Pinkstone Henry , Leuchtenberg Christian , Fraczek Justin , Anderson Bo
Published: March 2017

The AFGlobal Corporation has developed a mid-riser pump system targeted toward managed pressure drilling (MPD) wells that maintains a full riser fluid column and statically overbalanced well at all times while excluding the need for rig and riser modifications or multiple interconnected manifolds at topside. The optimized configuration of this system is envisioned to permit rapid deployment on any deepwater floating drilling vessel to serve as one method of controlling equivalent circulating density. Ultimately, the PRS will serve as a stepping stone to full dual gradient drilling.

Wellbore pressure is controlled by utilizing a subsea pump system to reduce the amount of riser annulus pressure exerted on the formation. The subsea pump system is operated in conjunction with an MPD wellbore seal permitting a configuration where the pump system can take suction from the riser below the MPD wellbore seal and discharge back into the riser above the MPD wellbore seal. As such, all riser flow is returned to the rig via the main flow line which also permits the option for conventional or advanced kick detection techniques. Since there is no independent mud return line out of the riser, the riser is always full of drilling mud. The topside footprint consists of a combined hydraulic power unit and pump controller skid and umbilical reel permitting 1-2 weeks of rig up time. The pump system and MPD wellbore seal are packaged as single unit which can be deployed through the rotary table in the same manner as a conventional joint of riser. By utilizing a positive displacement pump, the power requirement is low enough for installation across a broad range of drilling vessels.
Managed Pressure Drilling Application in Severely Depleted Reservoirs Enables Successful Brownfield Drilling Campaign
Authors: Beutler Amber , Coffey Scott
Published: March 2017

A re-entry drilling campaign of six highly deviated wells was successfully drilled from a fixed offshore platform through depleted reservoirs by utilizing managed pressure drilling in eight hole sections. The main challenge was the narrow drilling window of 0.05 to 0.60 ppg between wellbore stability mud weight, driven by unstable shales, and reduced fracture gradient of the reservoir sands, driven by depleted pore pressure. The necessity to balance risk of lost circulation, hole cleaning, and wellbore stability drove the team to employ new technology in order to achieve success.

Managed Pressure Drilling (MPD) is one of several technologies for optimizing drilling operations and reducing Non-Productive Time (NPT) while drilling narrow windows. The Surface Back Pressure (SBP) variant of MPD can be used not only on exploration wells with pore pressure uncertainties to identify and control influxes, but also can be employed in severely depleted reservoirs to enable drilling operations which are conventionally unattainable due to constricting drilling window.

This case study discusses the main objectives and requirements for MPD, along with the planning, equipment, and execution strategies used to drill and make connections with a mud weight statically underbalanced to wellbore stability gradient. Furthermore, the paper discusses the use of novel pressure testing techniques and automated fluid displacements with the MPD system to maintain a constant anchor point pressure prior to tripping and avoid losses and wellbore collapse. Finally, this study provides results, achievements, and recommendations on SBP application in a brownfield reservoir.
Planning of an MPD and Controlled Mud Cap Drilling CMCD Operation in the Barents Sea Using the CML Technology
Authors: Bysveen Johan , Fossli Børre , Stenshorne Per Christian , Skärgård Gustav , Hollman Landon
Published: March 2017

The subsurface formations and reservoir conditions encountered in certain areas of the Barents Sea offer some unique challenges for the operators and the drilling industry. These areas of the Norwegian Barents Sea consist of naturally fractured and weathered carbonate formations which may incorporate open karsts. Drilling into large open fractures or karsts will result in total losses and mud cap drilling practices must be employed to enable further progress. Such locations may require some unique solutions to drill effectively and safely while conforming to local rules and regulations; including deploying winterized rigs capable of year-round operations in Arctic environment.

This paper describes the process of selecting a viable solution for drilling in such an area where potential mud cap drilling practices could be required, the rig integration process, class notation process, development of operational procedures, risk assessment, training and testing of equipment prior to commencing the operation.

This was a fast track project which incorporated developing new mud cap drilling procedures and processes when operating the Controlled Mud Level (CML) system. Since mud cap drilling practices from a floater on the Norwegian Continental Shelf (NCS) is a rare occurrence, it required close cooperation between the operator, the drilling contractor and the service provider. To facilitate the process and assure sound practices a third party with experience on mud cap operations was also engaged. The paper will also briefly describe the Controlled Mud Cap Drilling (CMCD) principle and the results from drilling the well.
An Experimental Study on Riser Gas Behavior for Dual Gradient Drilling
Authors: Kaldirim Omer , Schubert Jerome J.
Published: March 2017

Offshore well costs and risks have proven the need for research in deep water drilling and well control. This paper presents the experimental research that is ongoing at the Dual Gradient Drilling Laboratory to understand the physics involved in gas migration.

A scaled prototype of an offshore well was built to mimic the Controlled Mud Level (CML) Drilling method. Instrumentation and cameras were used to monitor flow rate and gas liquid ratio. Set rates for the mud outflow and inflow were determined and tested at constant gas influx, by increasing the mud inflow in narrow increments.

The prototype was successfully tested and removed a large amount of gas from the system before the gas migrated into the voided section. The results of these tests show that using high mud inflow rates can eliminate the single bubble system, leading to a dispersed bubble system. With dispersed gas bubbles the removal of the gas is a process of determining an optimal outflow rate that would also accommodate the fluid level requirement. Also, it was observed that the geometry of the outflow line have a major effect on the gas flow behavior. With the reduced outlet diameter, a Bernoulli flow was observed which increased bubble dispersion.

This paper provides information regarding the research on gas behavior and migration in a scaled riser system during circulation. These experiments can be used to study the effects of flow rates on gas dispersion and elimination from the CML Drilling method.
Investigation of Transient Behavior During Dual-Gradient Drilling
Authors: Mendonsa A. J. , Schubert J. J. , Yuan Z.
Published: March 2017

As the industry seeks out exploration prospects in deeper water, the complexity of drilling in tight pore-pressure and fracture-pressure windows has become increasingly challenging. Dual-gradient drilling (DGD) offers a promising solution through more closely matching the natural pressure gradient of the water depth.

Coupled with imprecise nature of pore pressure prediction and formation strength, deepwater operations are subject to well control issues and losses due to fracture propagation. It is not uncommon to experience both influx and lost returns whilst drilling due to the nature of geological uncertainty.

This paper examines simulation results specific to a ‘Controlled Mud Level’ (CML) system. This subclass of DGD enables operators to adapt bottomhole pressure (BHP) through adjusting annular mud height. The system relies on a subsea pump module (SPM) attached to the riser at a given height. Drilling fluid is diverted to the SPM and pumped via a return line instead of the riser. The inlet pressure required to maintain the desired annular mud height governs circulation rate.

During transient events, such as a connection, the annular height is raised thereby accounting for loss of annular frictional pressure (AFP) once circulation stops. Conversely, when the connection resumes, riser level decreases to compensate for the AFP gain encountered. Mud height is raised to increase BHP during subsequent kill operations.

This paper presents simulated transient behavior using commercial drilling software while concurrently highlighting the importance of understanding dynamic hydraulics in a low-price environment where deepwater wells show progressively diminishing operational margins.
Twenty Years of Grain Sorghum and Soybean Yield Response to Tillage and N Fertilization of a Claypan Soil
Authors: Sweeney Daniel W.
Published: March 2017

Core Ideas

Long‐term sorghum and soybean response to tillage and N on claypan soil is limited.

Long‐term sorghum yields are often substantially less with no‐till on a claypan soil.

Subsurface N may result in greater sorghum yield than with surface applications.

Anhydrous NH3 applications to sorghum may partially ameliorate the no‐till yield penalty.

Long‐term soybean yields are little affected by tillage on a claypan soil.

Crops grown without tillage on claypan soils in the eastern Great Plains often yield less than with tillage, especially cereals that require careful management regarding N fertilization. The objective of this 20‐year study was to determine the response of grain sorghum [Sorghum bicolor (L.) Moench] and soybean [Glycine max (L.) Merr.] in rotation to tillage and N fertilization on a claypan soil in southeastern Kansas. Sorghum was affected by tillage, N fertilization, or their interaction, except in the first year. Sorghum yields averaged 22% lower, and were never greater, with no‐till than with conventional or reduced tillage. Nitrogen fertilization increased sorghum yield, largely because of the greater number of kernels per head. Yields with application of anhydrous NH3 averaged 12% more than with surface‐applied N sources. Yield in half of the crop years was affected by tillage × N fertilizer interactions, and the long‐term interaction suggests that in the lower‐yielding no‐till system, the response to anhydrous NH3 may be greater than in tilled systems. Soybean yield was little affected by tillage, the residual effect from N treatments, or their interaction. In 1986, conventional tillage resulted in greater yield than with no‐till, but the reverse was true in 2002, and there was no difference in yield among tillage systems in the other 8 years. Thus, the potential yield penalty for growing grain sorghum in a no‐till system may be partially ameliorated by subsurface anhydrous NH3 fertilization; however, tillage selection or N treatment residual may have little effect on long‐term soybean production on this claypan soil.
FEATURES OF REPRESENTATIONS OF TEENS RAISED IN AN ORPHANAGE ABOUT THE ROLE OF SPOUSES AND PARENTS
Authors: Grigoryeva E. V. , Fotina V. Yu.
Published: March 2017

The article investigates the perceptions orphaned teenagers holdabout the family and the role and responsibilities of spouses and parents in the family. It was found that orphans’ presentation about the role of spouses and parents are contradictory, distorted, not optimistic and insufficiently differentiated. Teenagers do not see the need for children to discuss their problems with their parents, but they believe that the main function of parents is to educate children. In their opinion, it is the children who unite and strengthen the family, but most teens would like to have one child, or do not plan to have children at all. According to the teenagers, a spouse does not dominate in the relationship, seeking compromise, but at the same orphans not expect full feedback, warmth, kindness and support from a spouse.
INFLUENCE OF AGE, GENDER AND TYPOLOGICAL FEATURES OF ADOLESCENTS ON THE FORMATION OF ADAPTIVE POSSIBILITIES IN THE CONDITIONS OF TRAINING IN MIDDLE SCHOOL. Message 1: Age and gender characteristics of the psycho-physiological and psycho-social adaptation
Authors: Kazin E. M. , Sviridova I. A. , Chetverik O. N. , Zarchenko P. Y. , Tarasova O. L. , Sherer T. I. , Fedorov A. I.
Published: March 2017

The article features a study of psychophysiological, social- psychological characteristics and coping strategies of middle school pupils with the aim to research their psychosocial and physiological adaptation, the level of stress resistance, motivational and behavioral characteristics. 90 pupils of 5th and 8th grades were studied. The article analyzes the complex neurodynamic and psychodynamic indicators of social and psychological adaptation-maladjustment, the functional state of the autonomic regulation of the heart rate features. It has been shown that a significant role in the formation of adaptive possibilities of students is determined by a combination of age and gender characteristics of personality, of neurodynamic and psychovegetative parameters. It was found that the structure of the functional system, which reflects the relationship of psycho-physiological and social-psychological characteristics, indicates the need for more profound identification of indicators of individual autonomic reactivity and psychovegetative provision of adaptive responses in adolescent students in school environment.
CHRISTIAN DISCOURSE IN YU. BUIDA’S NOVEL «THIEF, SPY AND MURDERER»
Authors: Kolmakova O. A.
Published: March 2017

In the modern Russian writer Yuri Buida’s novel "Thief, Spy and Murderer" (2014), Christian discourse reveals itself at different levels of the text’s organization: genre (autobiography / confession), imaginative (marginal, mad / poor in spirit), motivic (imperfection of human nature / sin), plot (the hard way the son to the father / parable of the prodigal son) and others. On the one hand, Christian allusions in the novel are a manifestation of intertextual poetics, creating a cultural context for the perception of the postmodern text. On the other hand, the Christian "code" is the most relevant for the disclosure of the philosophical and psychological content of the novel, as in Christian categories expressed by the author's attitude to the leading cultural meanings of the era, to modern man, and to himself.
THE NAME OF LUDWIG VAN BEETHOVEN AS THE PRECEDENT LEXICAL ITEM IN ANTHONY BURGESS’S NOVEL “A CLOCKWORK ORANGE”
Authors: Korobko L. V.
Published: March 2017

The article analyzes features of the proper name of Ludwig van Beethoven as well as represents its intentional use in the process of verbalization of the phenomenon “Music” (based on the novel “A Clockwork” by Orange A. Burgess). On the basis of a stage-by-stage research three models of the proper name Ludwig van Beethoven within the anthroponomical field of the literary discourse of A. Burgess were allocated: MODEL I [Personal name]; MODEL II [Surname]; MODEL III [Surname + Work of Art]. The use of the model [Personal name] – Ludwig van is prepotent and reflects the main character’s personal attitude towards the composer. Functional meanings of the proper name are defined, 4 lexical portraits of Beethoven are allocated: physiological, psychological, emotional and intellectual. Positive and negative signs of Beethoven are expressed by means of evaluative lexicon and antinomies in the analyzed novel. The positive characteristic of the composer prevails, which is connected with the greatness of his figure and is motivated by the main character’s affection to Beethoven. Beethoven’s educational, noble features belong to positive signs. Negative signs of the composer’s personality are reflected in his emotional and intellectual portraits as he is represented as a gloomy, angry, mad person. In Anthony Burgess’s novel “A Clockwork Orange” both universal and specific features of Ludwig van Beethoven are represented. The universal features include physical characteristics of the musician (deafness, long flying hair, etc.), and also recognition of genius of the composer and his creations. Beethoven’s character belongs to the sphere of universal and specific features. The fact of the detached, lonely lifestyle of the musician, his severe, gloomy character, which was caused by his disease, is wellknown. Annoyance, rage, hidden threat, penetrating look are the specific features which are allocated to Beethoven by the author of the novel A. Burgess.
THE ACTIVITIES OF THE MILITIA OF THE KEMEROVO REGION IN COMBATING DESERTION FROM PRODUCTION AND FRONT (1943 – 1945)
Authors: Burchak V. Ya.
Published: March 2017

The article discusses the activities of the militia of the Kemerovo Region for combating desertion from production and front in 1943 – 1945 with particular attention to the causes of the desertion from the industrial enterprises of the region in wartime. The article reflects the interaction of the Soviet and party bodies with police structures in addressing the problem of desertion, for the adoption of measures related to timely identification of persons who escaped from enterprises and front. The social danger of the phenomenon is represented in terms of complication of a criminogenic situation in the region. The article presents the regulatory framework, in accordance with which the prosecution of deserters from production and front was carried out, and shows the essence of the applied punishment. Some statistics on types of crimes committed by these categories of people are given. In preparing this study we used: the normative-legal acts, documents of the several funds of the State archive of Kemerovo Region (GAKO), a number of which is introduced into scientific circulation for the first time.
PLAYING THE JURAL GAME: RUSSIAN PEASANTS OF THE EARLY XX CENTURY USING LEGAL LOOPHOLES TO MAINTAIN THEIR INTERESTS (the Confrontation Between Migrants and Old Residents at Novo-Shulbinskoye Village)
Authors: Kirillov A. K. , Karavayeva A. G.
Published: March 2017

The article is a contribution to studying the gap between the upper and the lower estates of the Russian society at the early XX century. In particular, peasants' perception of law is taken as the subject of the investigation. One of the striking examples of conflicts between peasant migrants an old settlers in the course of the famous "Stolypin's migration" to Siberia provides ground for this research. The authors aim at detecting peasants' readiness to defend their interests using legal loopholes to circumvent legal barriers. Documents from a file of the governor's office (gubernskoye upravlenie) of State archive of the Tomsk region let us have an all-round impression of the case as far as they represent views of the both struggling sides (migrants and old settlers), opinion of the local authority (krestyansky nachalnik) and the motivated decision of the governor's office. Compared to the legislation and to the other similar cases, these documents allow us to make out the hidden motive (old residents' wish to keep their plough-land) for the formal subject of the struggle (rent payment for the right to live in the village cottages). The facts discovered by the authors prove that the struggle over cottages was only a legally competent form for the struggle over plough-land. The result obtained corrects the currently understated evaluation of the Russian emancipated peasants' readiness to maintain their interests by legally competent methods.