bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving Stage Isolation in Vaca Muerta Wells Through Observations from an Integrated Fiber Optic Pilot
Authors: Savitski Alexei A. , Lock Benjamin , Todea Felix , Fita Patricio , Formento Gabriel , Al Lawati Hawraa I. , Mondal Somnath , Ugueto Gustavo 
Published: January 2024

Abstract
The productivity of an unconventional well depends on reservoir quality that can be selected but not controlled and completions that can be optimized. The challenge with improving a completion design is the lack of information about the actual downhole performance. An ultimate requirement for an effective completion is to have isolation between two adjacent stages. The observations and recommendations for improving stage isolation are made from the first integrated fiber optic (FO) pilot in Vaca Muerta.
Shell conducted an integrated diagnostic pilot in Vaca Muerta that included acquisition of multiple data types, such as: permanent fiber optics installation, surface microseismic monitoring, downhole pressure gauges, mudlogging, open and cased hole logging. One of the objectives for this project was to evaluate stage isolation performance for different plug types. Stage isolation was analyzed based on the DAS and DTS interpretation in two wells equipped with permanent fiber optic cable. Complementary, isolation integrity test (IIT) was performed in three stages of each well during wireline pump down operations. These results are compared with the FO interpretations.
This paper summarizes observations from the real-time monitoring of operations on two wells landed in different zones. Three solutions for stage isolation were tested in these wells. A statistical analysis of their performance is presented. The interpretation of the isolation integrity test is summarized and discussed. The isolation results between FO and IIT are cross-checked. While all stages with IIT data have good isolation based on FO interpretation, three of IIT tests indicate the lack of isolation. This discrepancy is discussed in the paper. During the execution of the pilot, observations were made about the impact of the treatment schedule on the plug performance. Modifications were implemented during execution and recommendations are made for future completions.
The investigation extends to evaluating plug isolation failures using FO monitoring after pad-wide fracture stimulation. We enhance our analysis by including multifinger caliper measurements (pre and post stimulation) to assess deformation and ovality in FO-instrumented wells, aligning these observations with plug failure instances. A post-fracturing ovality difference between landing zones was identified. While plug isolation failures are often associated with ovalization, it's essential to note that no specific ovality threshold was found to reliably predicts plug isolation success. These insights deepen the understanding of stage isolation challenges across the well pad.
Assessment of Augmented Depletion Development Technology Across us Shale Plays
Authors: Merzoug Ahmed , Pandey Vibhas J. 
Published: January 2024

Abstract
The concept of Augmented Depletion Development (ADD) was introduced to the industry through a pilot project conducted in the Bakken play in the United States (US). These wells are open-hole wells drilled within the fractured network of a pad. They are not fractured stimulated deliberately but do produce and contribute to the overall production of the lease. In this study, we use numerical modeling to understand the potential performance of these wells in several plays across the US.
The study is based on results obtained from the simulations run on a numerical model that combines hydraulic fracturing, geomechanics, and reservoir flow in one code. This allows for a better understanding of the influence of different parameters on the performance of these wells and their potential influence on the well-performance. This study assesses ADD's potential in 4 US plays: Bakken, Eagle Ford, Midland, and the Anadarko Basin. The sensitivity was conducted based on the time of stimulation of the child well and the time of drilling the ADD well. The spacing of the existing wells is the one that existed before drilling of the ADD well. Incremental production from each of the scenarios was compared. An uncertainty analysis on proppant degradation was conducted to assess the effect of proppant degradation on the production decline.
Results showed that ADD wells’ performance varies from one play to another. The trend shows that these wells tend to perform better as the permeability improves. The incremental production is in the range of 5%-20% and was shown to be directly proportional to the well spacing. These wells produce lower volumes when drilled later in the field development phase as the pressure in the reservoir drops. In tighter spacings, these wells compete for the same volume as the stimulated wells. The proppant pack degradation with time results in reduced production, though the incremental production remains unchanged. Although these wells are not economically viable in all cases, their implementation does require wider well-spacing. For the best results such wells must be introduced at the onset of drilling program and should be made ready to produce at an early stage of field development.
This work is the first published simulation that attempts at assessing a new technology for various plays across the United States. The learnings from this study can be used as a benchmark for operators that are planning on implementing such wells in their field development programs.
Fracturing 30,000 ft Wells in Deepwater, Planning and Execution Learnings from the Gulf of Mexico
Authors: Lizak K. F. , Zhang Y. 
Published: January 2024

Abstract
As shallower reservoirs deplete, the search for hydrocarbons is going deeper in the Gulf of Mexico. These reservoirs generally have lower permeability than many of the shallower reservoirs and require massive hydraulic fractures to reach economical production rates.1–4 The reservoirs are generally over-pressured and can require heavy weight drilling and completion fluids for well control. Fracturing fluids are often weighted, with viscosity and friction that require customization to the long work strings to permit sufficient rates to effectively fracture the formation. The lower permeability in these reservoirs require massive volumes of proppant to achieve the desired fracture lengths and conductivities, which can lead to erosional and logistics issues. As drawdowns greater than 10,000 psi are planned early in these wells’ lives, the pumping schedules need to consider the effects of increased stress on the proppant and possible future fracture conductivity loss. Descriptions of these issues along with discussions of current and proposed future solutions are provided.
Performance Redefined: A Business-Centric Approach to Assessing Hydraulic Fracturing Execution
Authors: Mogck D. , Doucette J. 
Published: January 2024

Abstract
The hydraulic fracturing of an unconventional well is typically the single most significant component of the expenditure for that well; however, there is no industry standard for assessing the efficiency of that operation.
This work will present an approach for evaluating hydraulic fracturing performance that transcends commonly used key performance indicators (KPIs). Historically, the industry has focused on various metrics, such as pumping hours per day, to quantify a frac crew's efficiency. However, many commonly used KPIs may provide incomplete and sometimes misleading indicators of the actual performance of a given completions spread.
This paper will present examples of traditionally used KPIs, instances where they have gone wrong, and offer an alternative means of consolidating and visualizing data from various commonly available sources. The intent is to better diagnose drivers affecting the performance of a given hydraulic fracturing spread.
Commonly collected data from a hydraulic fracturing job, including rates, volumes, design parameters, and job logs, are transformed into consistent and easily understandable metrics. These data have been collected for hundreds of jobs and stages over the last few years and integrated into a dashboard to get a high-level understanding of performance. The authors of this paper have mined these data sets for examples to share lessons learned from experience and present some of the critical factors that can substantially impact performance.
A review of historically used KPIs (stages, hours, feet per day, transition times, etc.) will reveal that none are ideal, and many suffer significant flaws. For example, a typical ‘stage’ design can vary wildly between areas. Pumping hours per day do not account for actual output during those hours. Case studies will illustrate the potential pitfalls of traditional KPI tracking and introduce the value of a more comprehensive approach.
The methodology presented will divide the efficiency of a frac crew into a few broad buckets. The first encompasses surface efficiency - how physical operations on the well site affect the ability to pump. The second is hydraulic efficiency - quantifying how effectively the spread can attain and maintain the target pumping rate.
The final bucket focuses on capturing overall crew performance in a single metric – slurry volume pumped. The volume pumped per day captures daily performance, while cumulative volume pumped over time reveals macro efficiency trends.
Hydraulic fracturing KPIs have not been standardized. Additionally, they are often only evaluated and reviewed monthly or quarterly, not daily. Subsurface drivers of efficiency are also commonly neglected. To the authors' knowledge, this is the first work to present a methodology for holistically assessing a hydraulic fracturing operation's effectiveness and efficiency using a combination of surface and subsurface metrics trackable on a daily basis.
Shale & Tight Perforation Design Optimization
Authors: Lorehn O. , Cooper J. , Singh A. , Nizamidin N. , Chalmers R. , Galimzhanov S. 
Published: January 2024

Abstract
Improving cluster efficiency is critical for economic and efficient multi-cluster per stage fracturing in unconventional shale & tight horizontal well completion. This paper highlights the findings from a field trial to test different perforation design variables which contribute to cluster efficiency. The goal was to optimize perforation design parameters and improve cluster efficiency for a given stage, and thus the well in its entirety.
A two well trial was conducted across the same bench formation on a single pad in Midland Basin. In all, eight perforation designs were created using two set points (high and low) across three key perforation design variables: 1) perforation phasing & orientation, 2) perforation diameter, and 3) perforation friction. Each design was repeated eight times (i.e. eight stages) to allow for a meaningful number of data points. After stimulation operations were conducted an acoustic imaging technology was utilized to assess the perforation dimensions for all perforations post-fracture for all stages as well as various sets of pre-fracture perforations.
In total, the trial was conducted across 64 stages (8 perforation designs × 8 stages per perforation design) using a Design of Experiments (DoE) method to assign low or high set points for each perforation design to best ascertain the impact of each test variable on the response variable as well as test for multicollinearity across the test variables. The uniformity index metric was used as a proxy for cluster efficiency and was calculated using two methods (a) eroded perforation area increase, and (b) post frac perforation area. Based upon the results obtained from the acoustic imaging data set and the subsequent data analysis, the uniformity index improved with a perforation design that had higher average perforation friction, smaller perforation hole shot size and a 0 degree in-line perforation orientation.
The field trial results of uniformity index provided high quality statistical quantification of optimum perforation design parameters and its impact on cluster efficiency.
Evaluation of Completion Designs and Fracture Heterogeneity via an Instrumented Slant Monitor Well
Authors: Benish T. G. , Brown J. S , Chhatre S. S. , Decker K. K. , Habrial J. D. , Manchanda R. , Solomou A. , Vice D. S. 
Published: January 2024

Abstract
Data collected from a passive instrumented monitor well was used to differentiate conductive fracture length and fracture density generated by three different completion designs in the Midland basin. The monitor well was drilled slanting laterally away from a nearby producer and instrumented with fiber optics and a pressure gauge array. The fiber and gauges were monitored during stimulation of the offset well to measure the evolution of created fracture geometry as a function of distance, as well as at various times during production to infer conductive fracture geometries. Integrating the data sets permitted comparison between created fracture geometry and productive dimensions over time while also providing a better understanding of the heterogeneity of conductive fracture lengths within and amongst stages.
Both fiber and pressure measurements complemented each other to discern clear differences in the conductive fracture lengths between the 3 completion designs. The maximum conductive half-length and the distribution of smaller fractures detected by fiber both showed trends in stimulated rock volume between the different designs, while also quantifying the non-uniformity of fracture lengths generated from each stage. These trends were confirmed by the pressure depletion from each stimulation design as a function of distance from the stimulated well, as well as a novel pressure analysis method to infer fracture density. Together, these results have informed on subsequent decisions on stimulation design and well spacing.
Updating the Field Development Practices After the Acquisition of an Asset, an Eagle Ford Case Study
Authors: Pichon Stephane 
Published: January 2024

Abstract
This paper retraces the journey of an Operator to update a Field Development Plan after the acquisition of an asset in the Eagle Ford where drilling has been suspended for several years. The objective is to explore how development practices can be upgraded by updating completion, well spacing and management of the Parent-Child in the context of a mature asset. Now that the acreage is ours, what will we do to develop it?
The asset features different generations of completion styles from small hybrid to large slickwater treatments. Production performance is analyzed along with acquired data and field tests run by previous Operators. After a complete reservoir characterization (both petrophysics and geomechanics), an integrated numerical model for hydraulic fracturing and production is implemented by history matching 3 different pads along with performing a sensitivity study to explore various well spacing and completion scenarios for the new development. Finally, a new pad is drilled and completed with new data acquired to re-assess the accuracy of the assumption made during the pre-drill planning phase.
The history matching of existing pads, constrained by previous data acquisition programs, allows to understand hydraulic fracture geometry and build some certainty on the predictability of the numerical modelling. While the increase of completion intensity shows an increase in recovery, the question is how the additional stimulation volume should be distributed to maximize economics. Field test and numerical modelling show that too large of a number of perforation clusters might become counter-productive because of the trade-off with a lower volume per cluster. Post-frac perforation imaging is run in the new pad to assess the hypothesis. Well spacing and distance to nearby Parent offset is evaluated pre-drill, and observations from the completion and flow-back of the new pad are used to challenge the initial assessment. Offset pressure monitoring is performed with the neighboring pads to evaluate the potential interferences. Ultimately actual production of the new pad is compared against the pre-drill forecast with a reasonable agreement.
This work illustrates the complete cycle of development from the pre-drill study and planning to the post-drill analysis of the actual results. The methodology and learnings target key considerations around field development and are applicable to most Operators in tight resources.
Quantifying Hydraulic Fracture Geometry and Morphology in a Multi-Cluster, Multi-Stage, Hydraulically Fractured Well Using Volume-to-First-Response Analysis
Authors: Sarvaramini E. , Miller P. , Burnham J. , Kivari A. 
Published: January 2024

Abstract
This study presents a novel analytical framework aimed at replicating hydraulic fracturing geometry at the cluster level within a multi-cluster, multi-stage, hydraulically fractured well. The fundamental Sneddon's equation is utilized to develop a mathematical solution that quantifies poroelastic stress shadow effects, taking into account both inter and intra-stage and intra-stage stress shadowing effects. The proposed approach integrates the fundamental solution of a blade-like fracture in the Perkins-Kern-Nordgren (PKN) model to determine fracture geometry, considering fluid partitioning between clusters resulting from stress shadowing and cluster competition. The Volume-to-First-Response (VFR) parameter obtained from fracturing diagnostics, such as Fiber Optics or Sealed Wellbore Pressure Monitoring serves as the basis for replicating the fracture geometry at the cluster level. The application of the proposed methodology is demonstrated using an example of a horizontal well that is monitored by Sealed Wellbore Pressure Monitoring in the Montney Formation, located in the region of the Northeast British Columbia, Canada. The proposed method offers a rapid and efficient approach to utilize the VFR parameter for replicating hydraulic fracturing geometry on a cluster-by-cluster basis, capturing the fracture half-length and fracture height.
Incorporating ε-Polylysine Hydrochloride, Tea Polyphenols, Nisin, and Ascorbic Acid into Edible Coating Solutions: Effect on Oxidation and Structure of Marinated Egg Proteins
Authors: Liu Jingbo , Han Lu , Cheng Dongkun , Li Shengrao , Chen Xiumei , Yu Yiding , Zhang Deju , Zhang Ting 
Published: January 2024

Abstract
Egg processing products lose their attraction due to protein oxidation and degradation, while the edible coating incorporating antioxidant and antimicrobial agents can address this deficit. In this work, chitosan (CS) in combination with ε-polylysine hydrochloride, tea polyphenols, nisin, and vitamin C (CS-NH-TC) was applied as a novel edible coating material for preserving marinated eggs for 20 days and its effects on egg quality, and protein oxidation and structure were determined. The CS-NH-TC coating exhibited the highest antioxidant and antibacterial activities among all coatings. Compared to uncoated marinated eggs (Sulfhydryl: 12.02 μmol/g, dityrosine: 6251.8, protein hydrophobicity: 3691, turbidity: 0.13 mg/mL, particle size: 342.13 nm), CS- and CS-NH-TC-coated eggs exhibited improved protein stability, as evidenced by a higher sulfhydryl (22.20 and 30.92 μmol/g) and lower dityrosine content (4722 and 4216), protein hydrophobicity (2891.72 and 865.75), turbidity (0.06 and 0.03 mg/mL), and particle size (292.06 and 256.57 nm). Additionally, edible coatings, especially CS-NH-TC coatings, were positively correlated with smaller intermolecular force changes in marinated eggs, corresponding to suppressed protein oxidation and conformational changes. Furthermore, CS-NH-TC-coated samples showed more stable protein secondary structures and less disorderly and aggregated protein microstructure, and markedly protected the color, texture, and sensory scores of marinated eggs. Our study could provide a theoretical basis for stabilizing the protein structure of egg processing products.
Metabolic activities of marine ammonia-oxidizing archaea orchestrated by quorum sensing
Authors: PEREIRA Olivier , Qin Wei , Galand Pierre E. , Debroas Didier , Lami Raphael , Hochart Corentin , Zhou Yangkai , Zhou Jin , Zhang Chuanlun 
Published: January 2024

Abstract

Ammonia-oxidizing archaea (AOA) play crucial roles in marine carbon and nitrogen cycles by fixing inorganic carbon and performing the initial step of nitrification. Evaluation of carbon and nitrogen metabolism popularly relies on functional genes such as amoA and accA. Increasing studies suggest that quorum sensing (QS) mainly studied in biofilms for bacteria may serve as a universal communication and regulation mechanism among prokaryotes; however, this has yet to be demonstrated in marine planktonic archaea. To bridge this knowledge gap, we employed a combination of metabolic activity markers (amoA, accA, and grs) to elucidate the regulation of AOA-mediated nitrogen and carbon processes, including their interactions with the surrounding heterotrophic population. Through co-transcription investigations linking metabolic markers to potential key QS genes, we discovered that QS molecules could regulate AOA's carbon, nitrogen, and lipid metabolisms under different conditions. Interestingly, specific AOA ecotypes showed a preference for employing distinct QS systems and a distinct QS circuit involving typical population. Overall, our data demonstrate that QS orchestrates nitrogen and carbon metabolism, including the exchange of organic metabolites between AOA and surrounding heterotrophic bacteria, which has been previously overlooked in marine AOA research.
Real-time Fuzzy Position Control and Design of Star Parallel Robot
Authors: Aydın Muhammet 
Published: January 2024

Abstract

The goal of this study is to use fuzzy logic to develop and operate a specially made Star parallel robot inside a given working volume. The robot was constructed and outfitted with the required components after it was designed in Solidworks with a working volume of 20x20x20 cm³. Fuzzy logic was used in a Matlab/Simulink Real-time environment to accomplish real-time position control. The objective was to use reference values of x = 100 mm, y = 200 mm, and z = 480 mm to regulate the end effector's location. The robot demonstrated the efficacy of the control mechanism by reaching the intended values in 8.286 seconds with a maximum error of 0.08%, as per the results. The investigation shed light on the trajectory of the robot as well as the error convergence over time. This paper presents a unique design with a working volume for a Star parallel robot, introducing the first application of real-time fuzzy logic control. Furthermore, the Star parallel robot's forward kinematic equations were published in the literature for the first time.