bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating Geomechanical Considerations on Suitable Layer Selection for Hydraulically Fractured Horizontal Wells Placement in Tight Reservoirs
Authors: Al-Ameri Nagham Jasim , Hamd-Allah Sameera Mohammed , Abass Hazim Hussain 
Published: November 2020

Abstract
The instant global trend towards developing tight reservoir is great; however, development can be very challenging due to stress and geomechanical properties effect in horizontal well placement and hydraulic fracturing design. Many parameters are known to be important to determine the suitable layer for locating horizontal well such as petrophysical and geomechanical properties. In the present study, permeability sensitivity to stress is also considered in the best layer selection for well placement. The permeability sensitivity to the stress of the layers was investigated using measurements of 27 core sample at different confining stress values. 1-D mechanical earth model (MEM) was built and converted to a 3-D full-field geomechanical model to reach perfect layer choice. The analysis of results has diagnosed the maximum horizontal stress direction of NE-SW as determined using both Fullbore Formation Micro Imager FMI and sonic scanner anisotropy analysis. The effect of porosity and permeability compaction as a result of stress changes while reservoir depletion is including on the reservoir simulation model. The choice of best layer and optimum design criteria for hydraulic fracturing is done in the current study using a compaction simulation model with the results of available measurements of geomechanical properties. The results of the simulation model show that the formation sensitivity to stress is an important factor for detecting a suitable layer for horizontal wells placement. The results of MEM indicate that horizontal stress difference (Δσ) and unconfined compressive strength (UCS) are the most important factors among geomechanical parameters affected the layer selection. From simulation results, it was found that 225 to 275 m fracture half-length gives a higher increment in oil production. The optimum number of fracture stages is noticed to be 8 to 10 stages after which the increment in production will reduce.
Advanced Well Planning Using Natural Language Processing NLP and Data Science Models: Maximizing the Value of Data to Mitigate Costs and Risks in New Wells
Authors: Cumming John , Riggins Valentina , Hodson Paul , Walker Barry 
Published: November 2020

Abstract
A new methodology using data science models and natural language processing (NLP) model has been developed, enabling rapid well screening and automated recommendations of key planning parameters. Well Planning and Drilling engineers are empowered by this approach, able to perform quick analysis of all available relevant data, to come up with drilling plans and budgets, and a template for new wells based on the entire field drilling experience.
"Analog" well and "Cluster" were introduced as key concepts in the methodology. Analog wells are wells that have similar characteristics and are completed in the same reservoir as the proposed new well. Clustering techniques used were tested on a publicly available data set, shared by Equinor for the Volve Field.
Within the given data set, 5 clusters were identified by the similarity-based clustering algorithm. For each well cluster, a distance was calculated between wellbores and the averaged features of that cluster. Wellbores in the same cluster were used to anticipate type, duration and impact of NPT events.
The Similarity Index was introduced and a representative well bore for each of the clusters was devised. This representative wellbore was used as a benchmark for recommending casing, ROP, mud density, expected pore pressure, costs, drilling and completion time, expected NPT, among other parameters.
The results suggested that using a similarity index rather than simply using the nearby wells identified stronger similarities between wells than would be found based on proximity. It was determined that in this data set there were a number of wells that were not in the close proximity to the proposed well which were in fact closer analog wells than those which would have been used by taking the nearby wells.
The pre-calculation of clusters and similarity indices made the process of initial estimation for new wells very rapid and bias-free.
For the NLP exercise, the accuracy of classifying NPT achieved was 98% through selecting the optimal technique. The approach also highlighted the need for a dictionary with common abbreviations used in the drilling industry, to standardize and share meanings of terms across companies and even teams.
The proposed method overcomes the major limitations of user-biased process of manually gathering, with a limited data set transformed to an objective process, is inclusive of all wells in the field, and the value of automating results.
The technique is not a substitute for the detailed well engineering design required to develop a well design to AFE approval standard, however, the tool enables a much needed acceleration in well design achieving significant reduction in time, costs and risks.
Research on Radial Drilling Technology of High Efficient Rock Breaking Under High Temperature Deep Well Conditions
Authors: Chen Zhi , Zhu Feng , Hu Qiangfa , Zhang Youjun , Lv Weiping 
Published: November 2020

Abstract
The current radial well operation technology can not adapt to high temperature, and the long tripping period and low drilling efficiency in deep well conditions.According to the characteristics of abrasive jet, a new radial drilling method is proposed in this paper, in which the abrasive jet is conveyed to the underground by CT (coiled tubing), the casing is sidetracked first, and then the formation is drilled.
The working procedure is that using the CT to run the positioning and guiding tool in hole first, and then using the CT to run a steel tube in hole. When the steel tube reaches the deflector, it makes a radial turn, and the ground equipment transfers the abrasive drilling fluid to down hole through the CT. During the operation, the casing sidetracking is completed with drilling fluid with high abrasive concentration, then the abrasive concentration is reduced, and the steel tube enters the formation to complete the radial drilling.
Practice has proved that when the well temperature exceeds 100°C the jet hose is easy to be damaged under high temperature and high pressure environment, resulting in leakage of drilling fluid and unable to complete the operation normally. It is necessary to select a suitable temperature-resistant jet hose. Practice has proved that when the well depth is more than 4000 meters, the pressure loss along the system increases and the jet water power from the nozzle decreases. For hard formation, the water jet is not enough for rock breaking drilling in the formation. The results show that under the same water power condition, abrasive jet has stronger ability to break rock and penetrate hard stratum than water jet because it contains solid particles with higher hardness and density. At the same time, the abrasive water jet with suitable abrasive concentration and water power can be used for casing sidetracking. The casing sidetracking and formation drilling are combined to simplify the process. Experiments show that the types of abrasives, abrasive concentration, drilling fluid composition, drilling fluid water power, injection time affect the casing window opening and formation drilling effect.
The method introduced in this paper solves the technical problem of water jet radial drilling, which is easy to break jet hose at high temperature (180°C) and can not break rocks due to the decrease of water power in deep wells (4500 m), and expands the application scope of radial drilling technology. Secondly, it simplifies the working procedure and opens up a new construction technology.
Exception Based Surveillance on Gas Lift Performance Monitoring: A Novel Gas Lift Diagnostic Workflow in Field B
Authors: Jing Zhi Kueh , Alamsyah Hafidz , Musa Rizwan , Jamaluddin Muhamad Nasri , Abu Bakar Afdzal Hizamal , Mokhlis Mohamad Mustaqim , Hassan Muhammad Firdaus , Fuenmayor Roberto , Hashim Mohd Hafiz , Harith Mikhail , Trivedi Rajesh 
Published: November 2020

Abstract
This paper presents a process flow of an efficient method to diagnose, identify and optimize non-optimum gas lifted wells for a gas-lifted oil field. During normal day-to-day operations, a Petroleum Engineer's deliverables include well lifting performance analysis as well as optimization. Gas lifted wells are deemed optimized when the injection point is at the deepest mandrel possible and no multi-pointing scenario is occurring. However, the real-life well production can be unstable, corroborated by real-time data of flowing tubing-head pressure, casing head pressure and gas lift injection rate. The analysis of these real-time data can infer non-optimized lifting, where one of the symptoms is valve chatter. This in turn translates to well slugging and affects the whole production system. In a field with a large number of gas lifted wells, the diagnosis of these types of cases requires a substantial investment of time each month. By utilizing this workflow, the time spent for lifting diagnostics can be reduced, as well as contributing to time savings for other meaningful tasks, i.e. designing new gas lift system on non-optimized wells.
The Gas Lift Diagnostic workflow, which is developed using pre-defined logic and the existing well model, eliminates the time-consuming manual task that slows down work and streamlines the processes to generate more value for the business and organization.
Innovative Data Processing QA/QC for the World's Largest 3D Seismic Survey
Authors: Al Dhaheri Afra , Cambois Guillaume , Mahgoub Mohamed 
Published: November 2020

Abstract
With close to 90,000 km2 of onshore and offshore seismic data being acquired and processed in less than 5 years, ADNOC has introduced new innovative QCs to ensure the huge amount of data is properly vetted at each step of the processing sequence. The pre-stack time and depth processing flows are very demanding and amplitudes must be preserved throughout. We present four key diagnostics for QA/QC methods at critical steps in the processing sequence. These selected QA/QC are meant to achieve a resilient seismic data processing outcome amenable to all types of seismic interpretation, either conventional seismic interpretation or advanced seismic reservoir characterization or seismic quantitative interpretation.
Seismic bandwidth is the lynchpin of that QA/QC strategy and it will be kept in the spot light to make sure that no processing artifacts erode the acquired seismic bandwidth and that we ultimately preserve the original six octaves of the recorded seismic data. Additionally utilizing the full seismic waveform, either signal or noise, such as surface waves, ground roll, or mudroll, can help compute long wavelength static solutions. The near surface velocity model is a prerequisite for accurate depth imaging not only for the shallow overburden but also at target reservoir levels. We also explore unsupervised machine learning for the automatic detection of amplitude anomalies in ocean bottom nodes (OBN) and to estimate the velocity of the ground roll or mud roll surface wave noise given the huge amount of data we are dealing with.
Development and Subsequent Field Experiences Using Novel Dendrimeric Asphaltene Treatment Chemistries
Authors: McRae James Alexander , Mat Suandi Lizman , Ben Hamza Salah Eddine , Cole Rachael 
Published: November 2020

Abstract
Precipitation and deposition of asphaltenes is becoming a more common issue in the hydrocarbon production process from high pressure reservoirs. Asphaltenes are organic solids commonly considered to be polyaromatic structures with aliphatic chains, sometimes including other heteroatoms. Asphaltene formation in the near-wellbore area and downstream in production facilities can cause numerous flow assurance related issues.
This paper describes work performed in developing a novel class of materials, using dendrimers as a platform to inhibit asphaltene deposition in oilfield applications. Dendrimers, or hyperbranched polymers, are tree-like structures grown from a central core with repeating subunits that provide high molecular weight compounds.
This paper describes the initial development of the dendrimeric chemistries, including initial crude characterisation, laboratory performance evaluation of the products, and two subsequent successful field treatments. The data presented shows effective reduction of precipitation and deposition of asphaltenes both downhole via capillary injection and topsides in production facilities both previously encountering complicated asphaltene issues.
Derivation of Permeability Logs in Carbonate Cores Using X-Ray CT Textural Analysis
Authors: Dernaika Moustafa , Masalmeh Shehadeh , Koronfol Safouh , Gonzalez David , Aljallad Osama , Mahgoub Faris 
Published: November 2020

AbstractPermeability prediction is an important step in reservoir characterization for effective modeling of water-flood performance and subsequent EOR processes. Permeability should be determined accurately versus depth in all cored and logged wells in a field. This is normally achieved by the use of cross-plots of core permeability versus core porosity from log-derived porosity in un-cored wells. The main aim of this research is to use X-ray CT images of reservoir cores to identify geological textures and predict permeability based on well-established models in carbonates.Full-diameter reservoir cores were imaged using dual energy X-ray CT. Porosity logs were derived along the entire cores from the dual energy data. Textural variations were identified from the appearance of the CT images. Statistical sample selection was designed to honor the distribution of porosity and CT-textures. Porosity-permeability correlations were established in the texture domain using plug-scale poroperm data and thin-section photomicrograph analysis.Plug-scale geological analysis confirmed the CT textures in the images, which allowed the derivation of texture logs along the cores. The porosity and permeability data were fitted into unique trends that were derived from the detailed textural analysis. This process provided the link between the poroperm trends and the different textures in the core enabling permeability to be predicted along the entire whole core intervals.This paper describes a novel approach of combining textures with porosity to model permeability along the reservoir column. A unique dual energy CT technique was used to ensure that all the core property variations were well represented in the plug-scale core analysis measurements. This analysis will open the way for predicting permeability in un-cored wells using texture information from down-hole image logs. In the future, machine-learning algorithms will be employed following the same workflow for effective permeability prediction in the field.
RSS and Motor Directional Analysis Modelling: The Effect of Local Doglegs on RIH of Completions and Casing
Authors: Nobbs Benjamin , Menand Stephane , Dao Ngoc-Ha 
Published: November 2020

Abstract
Rotary steerable systems (RSS) and steerable motors pose their own unique challenges when modelling the bottomhole assembly (BHA) directional behavior. This paper aims to present a methodology that allows the anticipation of problems such as mechanically stuck pipe or lock up situations when running in hole casing or completion strings. The methodology consists of 3 tasks: evaluation of intermediate doglegs and wellbore tortuosity using a unique Rock-Bit-BHA analysis, modelling of the casing deformation including potential centralization and then modelling the run in hole (RIH) of the completion. The directional capabilities of a BHA are affected significantly by the selection of the drilling bit, type of directional drilling driving system and the type of formation. The resulting trajectory can be either very smooth or very tortuous with significant additional local doglegs. The deformation of the casing as well as the completion post buckling analysis is completed using a robust and field validated 3D stiff string Torque & Drag & Buckling model. This methodology can be applied before, during or after the well has been drilling. Used before or during the well construction process, an indication can be given as to whether the casing or completion can reach total depth (TD) using planned or actual data. Used after a lockup or stuck pipe incident, the methodology can give an indication if tortuosity was a contributing factor. Various field cases are presented and clearly show the benefit of the methodology including post-analysis of stuck standalone-screen (SAS) completion string in complex 3D drain and pre-analysis of completion run in hole (RIH) targeting a specific drain. Correctly evaluating the risk of BHA, casing and/or completion strings getting stuck or locked-up when RIH can ultimately provide a template for ultimate reduction of non productive time (NPT). This modeling results has been verified and discussed in the field.
A Novel Investigation of Power Quality Effects on Premature ESP Failures
Authors: Ratanatanyong Suwitcha , Chalermwai Apisit , Kanchanachinto Tanarat , Chantabutr Sirodom , Wasanapradit Tawan , Chigbo Ikenna 
Published: November 2020

Abstract
Electrical Submersible Pumps (ESP) are an essential artificial lift method in oil fields when the reservoir pressure is insufficient to drive the well fluid to the surface naturally. One of Mubadala Petroleum's operated fields in particular experienced several ESP failures from downhole ground faults, which resulted in a run life much shorter than the typical average run life experienced in similar applications. As such, power supply quality is investigated to understand whether it could accelerate ESP system breakdown.
Commonly, a Variable Frequency Drive (VFD) is employed to optimize operations as the reservoir conditions change. However, VFDs tend to generate transient and harmonic distortions as a result of electronic switching. Measurement tools, such as a power quality analyzer and an oscilloscope, are connected to VFD output to measure its power quality. Partial Discharge (PD) is considered to be a possible factor contributing to electrical failures. As such, a PD tool is connected to the medium voltage supplied to ESP to determine if any PD exists.
The investigation of power supply quality focuses on the percentage of Total Harmonic Distortion (%THD) at three different locations in the system; input and output of VFD, and output of the step-up transformer. Since there are no international standards in place to regulate the power quality output from the drive, different VFD models create different levels of output harmonics. Our results show that two different models can give different levels of %THD, both in terms of voltage and current. However, acceptable levels are observed for all of the designs tested, ranging from 2-15%. Power transient and voltage spikes were also measured during well startup and shutdown period, and indicated no significant differences between VFD models, and no issues of concern.
However, significant levels of partial discharge, as measured in nano-coulombs, are observed at the medium voltage measuring point through to the downhole cable connections. It indicated the possibility of electrical anomalies, which can result in cable insulation failure. The level of partial discharge on each specific connector piece can be performed further during the Dismantle, Inspection, and Failure Analysis (DIFA) process after the equipment is pulled out of the well.
The primary impact of high harmonic voltage distortion in ESP power systems is excessive heating, which can accelerate insulation resistance deterioration. Partial discharge can also contribute to insulation failure of downhole connectors and cable splicing points.
This paper provides a systematic approach to investigate the power quality system supplied to downhole ESP equipment, and the application of a partial discharge measurement method, which is new to the ESP industry.
A Novel Approach to Improve Acid Diversion Utilizing In-Situ Foam Generating Fluids
Authors: Al-Nakhli Ayman , Zefzafy Ibrahim , Ahmed Danish , Kharrat Wassim 
Published: November 2020

Abstract
Acidizing is a common stimulation treatment in carbonate reservoirs. Acid distribution over all layers and areas around a treated well is crucial for the matrix stimulation success. Effective acidizing, especially for long horizontal wells, requires acid diverting technique to insure uniform distribution along the wellbore intervals. Mechanical diversion is costly, while chemical diversion using in-situ gelled acid and viscoelastic surfactants have widely been applied during matrix stimulation. These chemical methods showed not only limited efficiency, but can introduce damage to the treated formation. Several chemical additives and complex formulations usually are used to ensure stability and success of diverting fluid application. This exercise greatly increases the treatment cost.
This study introduces a novel solution to improve acid diversion using in-situ foam generation. Thermochemical fluid is used to generate foam in-situ at downhole conditions, which will divert acid stages into not treated sections of the reservoirs. In this paper, two field treatments of two water injector wells, a vertical and a horizontal, were demonstrated using the new system. The in-situ foam generating fluid was used to divert acid in several pumping stages to ensure homogenous treatment. Pumping sequence and treatment mechanisms were described.
The results showed that in-situ foam generation approach has a very effective performance in diverting acid, with superior results compared to conventional diversion using viscoelastic surfactants. As the new system generates foam downhole, it showed very practical operation procedures. No pumping difficulties are experienced, compared with surface pumping to the foam. Having the reaction activated downhole, made the whole treatment safe and friendly to apply. Foam can occupy large areas, so less fluid is required to divert acid stage. Moreover, no complex formulation was required with several additives to ensure fluid activation downhole, which significantly reduced the overall treatment cost.
The novel method will enable effective and homogenous acidizing of carbonate reservoirs and eliminate the need for viscoelastic surfactants, which is expensive with limited effect. This work presents an effective method to place acid uniformly across a treated well using in-situ foam generation.