bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sequence Mining and Pattern Analysis in Drilling Reports with Deep Natural Language Processing
Authors: Hoffimann Julio , Mao Youli , Wesley Avinash , Taylor Aimee 
Published: October 2018

Abstract
Drilling activities in the oil and gas industry have been reported over decades for thousands of wells on a daily basis, yet little effort was made to analyze this text in large-scale for information retrieval, sequence mining, and pattern analysis. Drilling reports contain interpretations written by drillers from noting measurements in downhole sensors and surface equipment, and can be used for operation optimization and accident mitigation. In this initial work, a methodology is proposed for automatic classification of sentences written in drilling reports into three relevant labels (EVENT, SYMPTOM, and ACTION) for hundreds of wells in an actual field. Some of the main challenges in the text corpus were overcome, which include the high frequency of technical symbols, mistyping/abbreviation of technical terms, and the presence of incomplete sentences in the drilling reports. This work describes state-of-the-art classification accuracy obtained within this technical language and illustrates advanced queries enabled by the tool.
First Application of Fiber Based LCM in Srednebotuobinskoe Oilfield, Russia
Authors: Belyakov Andrey , Panov Maksim , Shirokov Ilya , Silko Nikita 
Published: October 2018

Abstract
Lost circulation is one of the main causes of nonproductive time during drilling in Eastern Siberia. In Srednebotuobinskoe oilfield major challenges are related to severely fractured igneous rock intrusion. Drilling through this interval is associated with constant severe to total losses. As a result, drilling velocity may drop below one meter per hour. Significant reduction of drilling time was achieved with application of an innovative fiber based LCM. Current paper describes results of this project.
Curing losses in severely fractured igneous rock formations is challenging. In most cases the fracture width is not known; it can only be predicted. However, this prediction is not always accurate.
An engineered fiber-based kill fluid was used to mitigate this lack of knowledge. Laboratory tests demonstrated ability to plug 1-5 mm fractures. System was applied in two wells in Srednebotuobinskoe oilfield. Fiber based pill was used in a combination with conventional LCMs. Additional operation time reduction was achieved by BHA compatibility. Average velocity of drilling through igneous rock interval was further compared to offset well from the same pad.
Drilling through 140 meters igneous rock interval of the well took around 147 hours. Conventional LCM are sensitive to fracture width. Due to geological complexity of the interval they had limited efficiency. A novel LCM based on soft, short fibers allowed to overcome this problem. It has a dual plugging mechanism. It can bridge across fractures up to 5 mm and form a filtercake on the formation surface, mitigating losses to the fractures network.
Applying this innovative solution in the 225 meters igneous rock interval of the second well (same pad) allowed to reduce drilling time to 119 hours. Thus, drilling became two times faster. Fiber based pill is also compatible with BHA, including telemetry. So additional time was saved on POOH/RIH operations. For the third well on the same pad pill placement strategy was further optimized. So, 135 meters igneous rock interval was completed in 23.5 hours. Drilling became 6 times faster comparing to the first well. Fiber based LCM showed high efficiency for mitigating severe losses in igneous rock intervals of Srednebotuobinskoe oilfield. BHA compatibility allowed to avoid additional POOH/RIH operations, providing extra value. Application of fiber based LCM led to significant acceleration of drilling igneous rock intervals.
The pill was prepared on the well site with equipment available. Compatibility with surface and downhole equipment was also confirmed.
Various successful field applications of fiber-based pills have been reported from various parts of the world. Current work presents first application of an engineered fiber based pill in Srednebotuobinskoe oilfield, Russia. The pill was pumped successfully in 2 wells in igneous rock intervals. Pill was placed through BHA. This solution allowed operator to achieve 6 times reduction of time required to complete the interval.
Wettability Quantification in Mixed-Wet Rocks Using a New NMR-Based Method: Experimental Model Verification
Authors: Newgord Chelsea , Tandon Saurabh , Rostami Ameneh , Heidari Zoya 
Published: October 2018

Abstract
Nuclear Magnetic Resonance (NMR) measurements have been attractive options for fast wettability characterization of rocks in petroleum reservoirs. Several NMR-based wettability indices are documented in previous publications. These methods often require calibration at irreducible water and residual hydrocarbon saturations, which complicates their applicability in mixed-wet rocks at different fluid saturations. We recently analytically derived a new NMR-based wettability index and confirmed its reliability using pore-scale NMR simulations. This new model only requires calibration at fully water- and hydrocarbon-saturated states for different wettability states ranging from water-wet to hydrocarbon-wet. In this paper, we experimentally quantify the influence of wettability on NMR measurements and verify the reliability of the new NMR-based wettability model in the core-scale domain for partially-saturated rocks.
First, we measured the transverse relaxation (T2) distribution of the unmodified water-wet samples using a 2-MHz NMR spectrometer in selected core samples. Then, we modified the wettability of two samples by injecting anionic surfactants. For the third sample, we injected a naphthenic acid and decane solution into the core. We quantified the wettability of these samples using the Amott-Harvey method and sessile drop contact angle measurements. Next, we measured the T2 distribution of the water-, mixed-, and hydrocarbon-wet samples at partially water- and hydrocarbon-saturation states. Finally, we assessed the wettability of these samples using the new NMR-based method and compared the wettability estimates to those obtained from the Amott-Harvey wettability method.
We measured the wettability of the core samples to be in the range of −0.6 to 0.5 on the Amott-Harvey index. The calculated NMR-based wettability for the altered core samples were in the range of −0.66 to 0.51, which was in good agreement with the wettability estimates from the Amott-Harvey method. The experimental results demonstrated that our new NMR-based wettability model successfully estimates the wettability of mixed-wet rocks in a wide range of wettability and eliminates the need for calibration at irreducible water and residual hydrocarbon saturations. The outcomes can be used to improve the speed and reliability of NMR-based wettability characterization. The results from these core-scale measurements are promising for application of the introduced model to log- and field-scale wettability assessment in mixed-wet rocks with complex pore-structure and at different fluid saturations.
High-Performance Inhibitive Water-Base Fluid System for Drilling Challenging Wells
Authors: Voitenko Dmitry , Ignatyev Sergey 
Published: October 2018

Summary
This article addresses the general results of using a high-performance inhibitive water-base fluid system for drilling horizontal extended reach wells (ERD) and two-casing wells on a field in West Siberia, Russia. It also reveals potentialities for drilling even more challenging wells, as well as prospects for future projects where drilling fluid systems of this type can be used.
High Salinity Swelling Polymeric Particles for EOR
Authors: Panthi Krishna , Sharma Himanshu , Lashgari Hamid , Mohanty Kishore 
Published: October 2018

Abstract
Most carbonate reservoirs have fractures which have a detrimental effect on sweep efficiency during oil recovery. The objective of this research is to block the big fractures with polymeric particles and divert the injection fluid into the matrix for better sweep efficiency during CO2 floods. Polymeric particles have been developed that swell as salinity is increased. These particles are termed SISPP or salinity induced swelling polymeric particles. SISPPs swell more in higher concentration brine contrary to common polymeric particle gels (PPGs) which shrink. Water flood and miscible floods are conducted in fractured cores with SISPP placed in the fractures. The SISPP placement increases oil recovery in fractured cores during high salinity water floods and miscible/CO2 floods. Furthermore, a model for particle swelling, and the concomitant change in permeability, as a function of brine salinity was implemented in UTCHEM, and single phase and oil recovery corefloods were modeled. UTCHEM simulations showed good agreement with the experimental results.
Safe Choice – Operationalizing Human Performance Science in Decision-Making
Authors: Santamaria Carla , Flood Jim K. , Schuberth Paul C. , Morell Jorge J. , Hinojosa Jaime R. , Haddock Justin , O'Donnell Hugh , Sandelands Eric , Cowan Mel , Higgins Alan 
Published: October 2018

Abstract
An approach for enhancing safety performance in Energy Industry field applications by integrating decision-making science will be presented. Results – both qualitative and quantitative – will demonstrate step change potential in safety performance in pursuit of plateau breakthrough to zero high severity incidents. Safe Choice empowers and enables safe decision-making at all levels of an organization by providing new knowledge and techniques, and linking these to current behavioral based safety practices.
Emerging understanding about brain and social science, as it relates to Energy Industry safety, is provided in practical discussion centered around decision-making. Workforce members are entrusted and empowered with new knowledge, personal decision-making style survey results, and an appreciative inquiry discussion that integrates brain science concepts in a simple effective way to their existing, familiar work processes and tools for managing safety and risk in their operating, drilling, and construction field sites. Following Safe Choice, individuals have a greater understanding of their own human performance and decision-making. Focusing on individual learning and awareness is the differentiator.
The program was first developed for the ExxonMobil Hebron Project integration, hook-up and commissioning construction site in Newfoundland and Labrador, Canada during 2015-2016. Together, with other transformational safety leadership initiatives, Safe Choice contributed to best-in-class safety performance. Safe Choice was then further developed and adapted for application within operating field sites during 2017. With further success, the program is now being implemented globally with an agile, user-centered design philosophy and approach.
The small group approach to training includes each worker receiving an individual decision-making style report and creates an atmosphere of appreciative inquiry, trust and openness. Developing leadership supporting strategies that foster a continuation of this atmosphere once back in the field (and outside of the classroom) has proven effective, with use of the new language and concepts evident in regular daily meetings such as toolbox talks, shift handover and safety meetings, as well as being used between workers during conversations in the field. Many locations where Safe Choice has been implemented have excellent safety performance, and will show both qualitative and quantitative measures of success achieved.
Energy Industry Leaders, Operations, Drilling, Construction and Safety Professionals will gain new knowledge on successful next-step integration of decision-making science into safety programs for protecting their workforce. This will expand and extend earlier insights from panel discussions at SPE HSSE Meetings in New Orleans (April 2017) and Abu Dhabi (April 2018). This paper includes results of the program so far.
Novel Analyses and Design of Relief Wells Considering 3D Effects
Authors: Sweeney Eugene , Zhou Lei , Gomes Paulo , Knight James 
Published: October 2018

Abstract
In developing a relief well contingency, current industry standard practice is to use a one-dimensional (1D) multiphase flow model to determine the requirements such as pump rate and mud weight to kill the blowout well. However, this does not consider certain variables. For instance, this analysis returns the same results regardless of the intercept angle of the relief well (i.e. results are identical if the relief well intercepts at a steep angle into the direction of flow, or if it intercepts at a steep angle in the same direction of flow).
A novel approach has been developed that considers the three-dimensional vector effects when a blowing out well is killed by means of a relief well intercept. This analysis offers safety and environmental benefits for well kill design and operations because it provides results which more accurately reflect the physical principles. This allows for optimization of a relief well design. For instance, this more comprehensive analysis allows the possibility to design a relief well with shallower intercept depth and lower pump requirements with the potential for an earlier kill.
This new method considers the complex interaction of the countercurrent flow that occurs at the relief well intercept and can utilize computational fluid dynamics (CFD). This enables optimization of parameters previously not considered such as specific spray design from the relief well. For instance, industry currently assumes that there is an advantage to pumping the kill fluid down the annulus of the relief well. The frictional losses are lowered (compared to pumping down the drillstring), thereby minimizng the pump requirements and maximizing the achievable rate for given pump capability. Whilst this may indeed be the case, the research covered in this paper shows that, depending on the circumstances, there can be a benefit to designing the spray pattern from the flow from the relief well at the intercept.
Various relief well kill cases were analyzed by both the standard method and the new method and the results compared. The new method predicted that relief well kills could be made with lower rates and pressures than predicted by the standard model. Using the new method offers an opportunity to increase the accuracy of relief well planning, enabling a more precise understanding of what may be achievable.
A test apparatus was designed and created to verify which of the two methods was more accurate. Physical experiments indicate that results from the proposed method match the test results closer than the standard approach.
Viscous Slickwater as Enabler for Improved Hydraulic Fracturing Design in Unconventional Reservoirs
Authors: Zhao Haiyan , Danican Samuel , Torres Hortencia , Christanti Yenny , Nikolaev Max , Makarychev-Mikhailov Sergey , Bonnell Andrew 
Published: October 2018

Abstract
The development of unconventional fields has experienced major efficiency gains. One main breakthrough in efficiency is the introduction of viscous slickwater fracturing fluids. Viscous slickwater enables placement of higher proppant concentration than conventional slickwater and is less damaging than guar-based fluid, leading to aggressive fracturing designs and improved production.
High viscosity friction reducer is the main component in viscous slickwater, which can replace hybrid and crosslinked fracturing fluids in unconventional reservoir completions. The successful application of high viscosity friction reducing fluid requires proper fluid hydration and adequate viscosity, which depends on water salinity and proppant concentration. We developed techniques for improved testing of friction reducers and friction reducer selection guidelines to support optimum placement of the fracturing design. A comparison of production results of wells fractured by viscous slickwater to those offset wells demonstrated the effectiveness of aggressive design with viscous slickwater fluids.
A high viscosity friction reducer was tested in the laboratory and applied in the field. Experimental data demonstrate a good correlation between low shear viscosity and proppant transport capability. Static and dynamic proppant transport data were used to design viscous slickwater to replace linear gel. The friction reducer has been successfully applied in the field in more than 3,000 stages. Formations that were traditionally fractured with crosslinked gel were successfully fractured using viscous slickwater with ease. Replacing conventional slickwater with viscous slickwater enables the transport of higher proppant concentration with little change in operations. Aggressive designs deliver a boost in production, thus confirming viscous slickwater as the fluid of choice.
Improved chemistry enables easier operations, faster well completion, and improved initial production, as confirmed by case studies. This study provides information for the application of viscous slickwater and the rigorous testing that is required and often overlooked.
New Kick-Off Procedure with RSS Reduces the Operation Time by 92%. Western Siberia Experience.
Authors: Teregulov Oleg , Shakurov Rafael , Sirotin Denis 
Published: October 2018

Abstract
Drilling multilateral (fishbone) wells in western Siberia is a common practice. A particular characteristic of these wells is the kickoff in the openhole horizontal section—no cement plug or whipstock is used. In the overwhelming majority of wells, it is economically impractical to perform tripping procedures twice—to change the bottomhole assembly (BHA) for the kickoff, and change it again for subsequent drilling. To reduce the well construction time, one requirement is to drill the horizontal section in one run.
Many operators have realized the advantages of using rotary steerable systems (RSS) for drilling multilateral wells that are becoming more complicated. During a well startup, the use of RSS to drill fishbone wells caused some concern about kickoff procedures. The operator had no experience with the process due to the analogue of adjustable kick-off sub (AKO) on the positive displacement motor PDM absence. The first kickoffs were made and resulted in a significant time increase compared to the same process with (PDM): 26 to 28 hours instead of 16 to 20 hours. Further experience with using kickoffs with RSS resulted in procedures and process improvements.
Based on the experience gained, a new kickoff procedure with RSS was tested at more than 20 jobsites in Western Siberia. A notable record was achieved on one of the multilateral wells on March 18, 2018 at the job for Lukoil-Zapadnaya Sibir Ltd. The kickoff in the open horizontal section was made in 1 hour 40 minutes, whereas the standard procedure took 20 hours 30 minutes. The time reduction of the kickoff process was 92% compared to the standard procedure, and 17% compared to the previous set record. The next stage of this technology will be its application in Eastern Siberia, with some modifications based on the lithostratigraphic section of the target horizon.
Application of Discrete Element Method for Modelling Sand Control Systems
Authors: Lezhnev Konstantin 
Published: October 2018

Abstract
Sand production is a major problem on weakly-consolidated fields. To limit the sand flow into the well, downhole filters are used. Filter sizing criteria, however, only work for a narrow range of rocks. Optimal sizing criterion suggests size of filter pores small enough not to let coarse particles to enter the well, but big enough so that skin-factor would not be too big. The aim of this article is to propose a method to create universal sizing criteria for any rock and filter type.
To model suspension flow through filter Discrete Element Method (DEM) was used. It suggests modeling system on the scale of single rock grains, which allows reconstructing all the microscopic mechanisms and interactions during filtration process. Particles were spherical, their sizes differed from 40 to 1400 μm. Interactions between particles were via Hertz forces. Different types of filters were considered: slotted liners (SL) and Gravel Packs (GP).
Based on the DEM models number of numerical experiments was carried out. Recomendations to sizing criterions and a method to evaluate Gravel Pack's skin-factor are proposed.
Evolution of Natural Gas Business Model with Deregulation, Financial Instruments, Technology Solutions, and Rising LNG Export. Comparative Study of Projects Inside the US and Abroad
Authors: Talipova Amina , Parsegov Sergei 
Published: October 2018

Abstract
One of the primary energy sources, natural gas is widely used for power generation, industrial production, transportation, commercial buildings, and households. The industry is a capital intensive one for all stages from exploration to delivery. Two types of supplies: pipeline and Liquefied Natural Gas (LNG), recently have faced a direct intra-industrial competition. Physical nature of methane and associated transportation costs lead to domination of so-called "natural monopolies" or "national champions" and strict government regulation, which postponed the development of free trade and competition. After decades of technical innovations and cost curve improvement in LNG sector, increasing global energy consumption, shale boom in the USA, and demand for supply diversification reformulated the role of gas in the global energy balance. While the pipeline sector remains to be in the hands of large corporations and a subject of strategic interstate and international agreements, LNG provides more diversity and flexibility of trade. However, even after a long history of LNG shipment since the late 1950s, this market is still regional with high spreads between countries and terms of delivery.
The paper presents the evolution of business models in the natural gas industry, focusing on the primary drivers as government regulation, technologies, and regional markets trends on the way to liberalization and cointegration. Thus, our primary objective is to show relative influence power of these drivers. This analysis also defines the competitiveness of corporate business model under conditions of asymmetric information in regional gas markets, deregulation trends, fast-growing production technologies and downstream infrastructure (specifically in the LNG sector). We also enclose the analysis of the most globally competitive gas projects. We analyze changes in value chain change and trading contracts. Our methodological approach poses model-based principles, including option and contract models, jointly with game theory elements.