bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coupled Fluid-Solid Geomechanical Modeling of Multiple Hydraulic Fractures Interacting with Natural Fractures and the Resulting Proppant Distribution
Authors: Raymond S. , Aimene Y. , Nairn J. , Ouenes A. 
Published: October 2015

Abstract
The application of a new Material Point Method (MPM) approach to model the proppant distribution in a reservoir where hydraulic fractures interact with natural fractures is presented and validated with an Eagle Ford well. The new MPM approach uses particles to represent the slurry and its effects on the hydraulic and natural fractures. The particles are injected in the hydraulic fractures and their action causes the hydraulic fractures to propagate and interact with the natural fractures thus providing new pathways for the proppant to move away from the wellbore when optimal natural fracture orientations are encountered. Elementary tests, conducted with the new MPM approach show that fractures oriented in certain directions close to the hydraulic fracture orientation facilitate the proppant placement while other fracture orientations that are perpendicular to the hydraulic fracture or close to perpendicular direction appear to cause screen out. When using the new MPM approach on multiple interacting natural fractures with different orientations the same conclusions observed with one single fractures still hold and only those close to the orientation of the hydraulic fractures promote the placement of the proppant. The application of the new technology to an Eagle Ford well shows that the simulated proppant travels the farthest in the frac stage that is known from other methods and measurements to be the one with the best half fracture length. Furthermore, the examination of the simulated proppant concentration curve versus time shows striking similarities with the actual slurry concentration measured at the same well. These encouraging results show that the macroscopic modeling of proppant distribution using the new MPM technology could help improve our understanding of the complex hydraulic fracturing process and the resulting proppant distribution.
Simulation Study of Zipper Fracturing Using an Unconventional Fracture Model
Authors: Qiu Fangda , Porcu Matteo Marongiu , Xu Jian , Malpani Raj , Pankaj Piyush , Pope Timothy L. 
Published: October 2015

Abstract
In the past decade the industry has embraced unconventional resources; namely, shale oil and shale gas. After the initial drill-to-hold stage, multiwell pad drilling and stimulations are employed to exploit the acreage. Zipper fracturing is a technique that reduces the standby time (up to 50% reduction, when combined with the plug-and-perf isolation method). Because of this operational efficiency improvement, zipper fracturing has become one of the most common fracturing practices for unconventional reservoir stimulation. It has also been purported to increase production, which several authors have previously reported. There are also other studies showing no benefit of zipper fracturing on production performance.
In this paper we have used a complex fracture network model, which we refer to as the Unconventional Fracture Model (UFM), to study zipper fracturing. The model simulates complex (branched) fracture propagation, associated stress shadows, fluid flow, and proppant transportation in the complex fracture network. The model solves the fully coupled problem of fluid flow in the fracture network and elastic deformation of the fracture. A key difference between UFM and the conventional planar fracture model is being able to simulate the interaction of hydraulic fractures with preexisting natural fractures (also referred as planes of weakness). The UFM simulates interwell and interstage stress shadows and honors both sequential fracturing and zipper fracturing scenarios' geomechanical interaction.
In this paper, we present the results of a zipper and sequential fracturing study that includes the completion design optimization and the associated production performance in the Eagle Ford Shale. The study provides a workflow to optimize the completion and stimulation designs in pad development and to improve rate of return. The quantitative results show that zipper fracturing may not deliver a production benefit when compared with sequential fracturing and is a function of well spacing and perforation cluster spacing in a given area.
Developing The Business Case For Water Management Planning Integration
Authors: Neir Alyssa , Taylor Tekla 
Published: October 2015

Abstract
It is well documented that the cost of managing produced water amounts to a significant portion of the operating cost of an unconventional well over its lifetime. The greatest factor attributing to this cost is transportation, which can be addressed through logistical planning. However, effective logistical planning begins at the early phases of a project during reservoir engineering and drilling and production scheduling. But making the case for early phase water management planning can be challenging when there is limited field data and engineering priorities have not yet been established. This paper will look at how dynamic simulation modeling can be used to cost effectively optimize facility engineering while taking into consideration water management planning objectives.
Water management and facilities planning is an iterative process that is affected by many different inputs, ranging from environmental constraints to oil and gas production targets to power and energy demands. Putting these into a dynamic context that supports early phase scenario planning allows diverse members of the development team (reservoir, completions, facilities, water and environmental engineers) to understand the impacts of various constraints on the development schedule, well production, and capital and operating costs. Having this information in hand early in the project also allows the team to work together to quantify the impacts of various water management scenarios on exploration and production and conversely, the impact of the exploration and production decisions on future water sourcing and reuse opportunities.
Using a dynamic simulation modeling process to evaluate these scenarios and provide meaningful output and documentation can help management to prioritize their cost savings goals, balance trade-offs between water management and facility engineering objectives and communicate their business decisions to the necessary stakeholders. In addition to evaluating the engineering viability and economic impacts, a dynamic simulation model can also take into consideration the area-wide impacts to water, air and the ecosystem under various planning scenarios, and can be used to support play-based water management planning and permitting and industry collaboration.
Numerical Study of Production Mechanisms in Unconventional Liquid-Rich Shale Volatile Oil Reservoirs
Authors: Khoshghadam M. , Khanal A. , Makinde I. , Lee W. J. , Rabinejadganji N. 
Published: October 2015

Abstract
Liquid-rich shale (LRS) volatile oil plays exhibit several challenges to modeling and analyzing such as flattened produced gas oil ratio (GOR), complex phase behavior, rock properties and fluid flow influenced by pore proximity effects in nano pores. In this study we investigated multi-phase flow and the governing flow mechanisms in these resources using a new procedure to divide shale matrix into different sub-media and a new methodology to model well performance.
We have developed new correlations for modifying PVT properties in nano pores to incorporate the impact of nano-pore confinement on phase behavior. We have subdivided shale matrix into three zones, nano-pores, micro pores, and natural (macro) fractures along with propped fractures with distinctive PVT, rock compaction and relative permeability properties in a compositional simulation model. We have implemented logarithmically-spaced local grid refinement (LS-LGR) to track saturation and pressure changes around the hydraulic fracture. Results from our new method were validated against production data from several LRS oil wells in the Eagle Ford shale.
Our numerical model reproduced anomalous produced GOR's that have been observed in liquid-rich shale oil wells. The study showed that the main impacts of nano-pore confinement on phase behavior, rock properties and fluid flow are reduction of bubble point, enhancement of critical gas saturation and severe permeability reduction due to compaction. Delayed development of two-phase flow as a result of reduction of the bubble point pressure in nano-pores causes the "flat" GOR's observed in early stages of production. Enhancement of critical gas saturation delays mobilization of gas molecules in nano-pores and could extend non-intuitive GOR behavior further when reservoir pressure drops below the bubble point. We found that ultimate oil recovery could change more than 20% by permeability reduction due to compaction. The study revealed that the period of constant produced GOR depends on the volatility of the reservoir fluid and pore size distribution in the reservoir. For moderate-GOR oil reservoirs, the constant GOR duration is greater than for highly volatile oil reservoirs, as well as in reservoirs with a greater percentage of nano pores.
The methodology introduced in this study allows us to better model LRS volatile oil wells and to estimate EUR more accurately. These new correlations for modifying bulk PVT properties under confinement combined with numerical models enables reservoir engineers to understand better the complicated physics in LRS volatile oil reservoir performance.
Achieving Environmental Excellence: Through 3R Waste Management
Authors: Pratama Ageng Yoga 
Published: October 2015

Abstract
The expansion of company operational activities has produced a large increase in waste generation. All of this waste must be handled responsibly, and can be a considerable resource if managed effectively. PT Medco E&P – Rimau Asset has therefore been applying integrated waste management to manage its organic and inorganic waste. This program will improve the Company's ability to manage the environment, minimize environmental pollution, and utilize organic and inorganic waste as a resource.
Company management has a strong commitment to improving environmental management by emphasizing cleaner production through a "reuse, reduce and recycle" strategy for resources and waste. Organic waste-paper management has been applied through reusing paper or using both sides of paper, and using an online system as the standard means of communication or messaging among sections and departments, therefore, minimalizing the use of organic paper.
Waste recycling has also been applied to produce compost from organic waste. Furthermore, the compost has been used to replace chemical fertilizer for re-vegetation activities. Meanwhile, organic waste-paper is being treated for recycling organic waste-paper and converted into calendars, business cards, portfolio and envelopes.
These integrated waste management activities support PT Medco E&P Indonesia – Rimau Asset in solving the problem of organic and inorganic waste management and in addition have resulted in PT Medco E&P Indonesia – Rimau Asset being awarded the Gold Rating from the Ministry of Environment, Republic of Indonesia in 2011. PT Medco E&P Indonesia – Rimau Asset, was therefore the first E&P Company in Indonesia to be awarded the highest rating in environment management in Indonesia, a major achievement for the Company.
Cementing Optimization through an Enhanced Ultrasonic Imaging Tool
Authors: Su Hongsheng , Zheng Yongsheng , Qi Jing , Gao Fei , Guo Yabin , Taoutaou Salim , Wang Rui , An Yongliang , Guo Hongzhi 
Published: October 2015

Abstract
This paper demonstrates a successful practice on how to optimize centralizer placement through analyzing the measured casing standoff by an enhanced ultrasonic imaging tool in one underground gas storage (UGS) project in west China.
In the initial phase of the project, it was found that the cementing bonding in the dual casing section was commonly unsatisfactory in the production liner cementing. Factors that affect cementing quality, including fluid density/rheology hierarchy, pumped fluid volume, and pumping rate, were verified and excluded from consideration as possible causes for the bad bonding. With the measured casing standoff from one ultrasonic imaging tool, acentric casing resulting in bad mud removal was identified as the root cause. Centralizer placement was optimized with a specialized software simulation and, as a result, the subsequent drilled wells were cemented with excellent quality.
The imaging tool combines conventional ultrasonic pulse-echo techniques and flexural waveform attenuation measurement. Real casing standoff can be computed based on third-interface echo measurement. With the measured standoff, engineers can re-evaluate the original centralizer design and analyze whether there is a relationship between unsatisfied standoff and poor cement bonding, on basis of which engineers can improve centralizer placement for the following jobs to achieve better cementing quality.
Previously, engineers did not have a way to realistically evaluate their centralizer designs as the standoff results could only be simulated virtually. By adopting this new imaging tool, a new approach in the cementing design, execution, and evaluation cycle is established, which is proven to be an effective method to enhance cementing quality in the UGS project.
The Channel Fracturing Technique Improves Tight Reservoir Potential in the Ordos Basin, China
Authors: Anqi Li , Lijun Mu , Xianwen Li , Haihua Yang , Judd Tobias , Yaolan Liu 
Published: October 2015

Abstract
The Ordos basin, located in northwest China, has large known hydrocarbon reserves that represent unique reservoir challenges and require specific operational, logistical, and technical expertise. One of the immediate objectives for PetroChina Changqing is to exploit these low-permeability oil and gas sandstones of the Yanchang formation, and this is done through both vertical and horizontal wells types that include single-stage and multistage hydraulic fracturing treatments.
Historically, individual well productivity has been impacted by complex reservoir dynamics, uncertain subsurface properties, and identifying those areas where critical geological and reservoir factors exist in order to generate substantial production. However, most hydraulic fracturing treatments result in low production rates due to reservoir pressure being below the hydrostatic pressure gradient. Therefore, principal fracturing challenges include trying to engineer a highly conductive flow path that depends on fluid viscosity and stability to build geometry and transport proppant toward the fracture tip, while rapidly returning to the base-fluid viscosity to be flowed back.
Since reduced fracture conductivity and length were detrimental to well performance, a hydraulic fracturing technique that incorporates the creation of channels within the fracture was deployed. This technology optimized reservoir inflow performance through a specified engineering workflow that requires specific equipment and pumping controls with fluid and fiber technologies. These channels created infinite-conductivity paths for fluid to flow from the reservoir to the wellbore, resulting in higher well productivity.
The deployment and application of this technology included 65 treatments performed on five vertical and five horizontal wells in oil blocks and two vertical wells in a gas block. Production performance for all oil wells treated with the flow-channel fracturing technique had initial production index figures being 2.4 times the field average and those wells continue to be upper performers when compared to 180-day accumulated production figures. For the gas wells, 4 to 5 times initial gas production rate was achieved when compared to the average offset wells. In all well cases, channel fracturing increased operational efficiency while resulting in no screenouts.
Buffer Basin Cleaning; Combination Between Operation Excellence and Environmental Compliance With 3R (Reduce, Reuse, Recycle) Approach
Authors: Siboro M. , Witono J. A. , Rusdi R. K. , Hartoyo O. S. 
Published: October 2015

Abstract
In 2012, Total E&P Indonesie (TEPI) decided to conduct cleaning of Buffer Basin. Buffer Basin is an open concrete basin connected to downstream of API Separator (integrated system in New Oily Water Treatment/ NOWT, Senipah Terminal). Originally, Buffer Basin was designed to handle fluctuation/ excessive flow of incoming oily water from process (e.g. from separator and storage tank draining). The biggest impact of isolating buffer basin is stopping liquid production of all TEPI sites. This generates long discussion and trial before the implementation. Consequently, accumulations of sludge/ sand were affecting not only the quality of the discharged produced water but also the health of people/ personnel due to the massive generation of BTEX (Benzene, Toluene, Ethyl Benzene, and Xylene). The key factor of Buffer Basin cleaning was the successful re-activation of old OWTU to temporarily bypass the incoming oily water treatment. During this temporary period, no process shutdown was experienced which may impact occurrence of production loss. The oily water treatment operating cost was reduced by approximately 50% due to reduction on chemical injection. The quality of disposed water to environment is still below permit requirement. Meanwhile, cleaning the Buffer Basin itself was challenging due to huge amount and various properties of sludge/ solid, highly impacted by weather, hazardous material exposure, etc. The sludge was treated using Sludge Oil Recovery (SOR) process resulting in 4 derivatives/ products (recovered oil, solid, emulsion, and oily water). To comply with environment regulation, upon relevant Government Bodies approval, TEPI in cooperation with licensed Contractor used 3R (Reduced, Reuse, Recycle) approach to manage the waste. The solid waste was processed to become fire resistant bricks which can later on be used as heat insulation. The emulsion was used as synthetic fuel and become energy source for making the bricks. The water was treated in oily water treatment unit prior disposal to environment. Recovered oil was sent back to TEPI's storage tank. The project was completed and all the challenges were overcome.
Relative Permeability Modifier (RPM) as Chemical Diverter in Bullhead Matrix Acidizing Treatment
Authors: Salman Hayatullah M. , Ridwan Ridwan , Raihan Raihan , Meifresia Lisa , Kurniawan Hafidz , Napitupulu Benni Hermanto 
Published: October 2015

Abstract
Matrix acidizing treatments are widely used for stimulating oil producing wells in the Zamrud field because of damage caused by scale plugging. The success of this matrix acidizing treatment depends on the uniform distribution of the treating fluid over the entire hydrocarbon-producing zone (Hill et al. 1994). Most oil producing wells are not homogeneous and contain sections of varying permeability—when fluids are pumped into a well, they naturally tend to flow into the zone with the highest permeability or less damage (Eoff et al. 2004). Being able to completely acidize the interval is a major problem.
Historically, mechanical techniques using packers has been employed by this operator to control the placement of acid fluid into the wellbore. One of the greatest challenges is that, although mechanical techniques are very effective, they are more time consuming than chemical techniques. Mechanical techniques divert treatment fluids from the wellbore; however, there is no control once the fluid enters the formation. On average, from four wells that were acidized using mechanical techniques, the post production performance was not satisfying—no production increase.
For many years, relative permeability modifiers (RPMs) have received a great deal of attention from the oil and gas industry. RPMs offer the option of bullheading an acid treatment without zonal isolation, and they are also designed to decrease water production with little or no decrease in oil or gas production. It is a solids-free diverter, opposed to the plugging mechanism of typical particulate diverters; it can be used for sandstone and carbonate formations with temperatures of 80 to 350°F and a permeability of approximately 6 darcys. The RPM system is placed in alternating stage(s) with the acid throughout the entire treatment. The first stage containing RPM predominantly will enter the most permeable area; it will change the effective permeability of the zones where it is adsorbed, diverting the following acid stage(s) to other zones or sections of the rock. Furthermore, in rock containing significant proportions of sandstone-type lithology, the water permeability of the treated zone is decreased permanently, resulting in post-treatment reduced water production from the treated zone. This paper discusses the geological and reservoir parameters of the wells, job design consideration, and post acidizing results when using RPM as a chemical diversion technique. Field results show significant improvement of post-stimulation production after combined acid with RPM systems were implemented in comparison to offset wells acidized with mechanical techniques in the same reservoir and at the same level.
Adapting Fracture Corridors and Diffuse Fractures in Single Porosity Model of Ujung Pangkah Carbonate Reservoir
Authors: Saputra Rini , Hidayat Azalea , Rahmanto Wahyu Agung 
Published: October 2015

Abstract
A practical method to adapt fractures both micro and macro as flow enhancing properties in a single porosity model is introduced to simulate Ujung Pangkah fractured carbonate reservoir. This approach is taken because dual porosity modeling attempt fails to explain the behavior of many wells which experience early water breakthrough and/or excessive water production in Ujung Pangkah field.
The enhancement factor term is used to define the degree of permeability enhancement by diffuse or micro fractures. At well location, the enhancement factor can be determined by the ratio of production test to the production of matrix-only model. The enhancement factor 3D distribution is derived from well data and seismic minimum curvature attributes as trend. Fracture corridors correspond to macro fractures in the order of meters extending vertically and/or laterally. As normally scattered spatially, fracture corridors cannot be modeled in a discrete fracture network model which is the integral part of dual porosity model. Some wells show behavior anomalies, such as rapid, early water breakthrough with excessive water production in unlikely location. It is observed that the location of these anomalies coincide with the fracture lineaments derived from the seismic incoherency attribute.
As the fractures are well characterized, diffuse fractures as permeability enhancement and fracture corridors as high permeability streaks, the further improvement of history match is then easily achieved by calibrating two other key parameters; relative permeability curves and aquifer strength. The relative permeability is calibrated to the shape of fracture relative permeability. Oil rate match is greatly improved. Water rate match is achieved by placing adequate aquifer strength.
Reservoir dynamic of Ujung Pangkah carbonate fractured reservoir can be simulated as a single porosity model with permeability enhancement adapted from two types of fracture distribution. Diffuse fractures enhance the overall permeability and fracture corridors dominantly influence flow dynamic in certain local area. Compared to dual porosity model, adapting fractures as permeability enhancement in single porosity model is more practical, more efficient in simulation run time – computational cost.