bluuebunny/crossref_metadata_2025 huggingface dataset:
Prinsip Sopan Santun Leech dalam Dialog Film Pendek “Ibu” di Channel Youtube Bakar Production
Authors: Khasanah Miftoqul , Setiawan Budhi , Wijayanti Kenfitria Diah
Published: September 2024

The implementation of politeness principles can still be found in a film, one of which is the short film "Ibu" on the YouTube channel Bakar Production. Adhering to these politeness principles can serve as an example for viewers of the film. Therefore, this study aims to describe and explain the politeness principles (maxim of wisdom, maxim of generosity, maxim of praise, maxim of humility, maxim of agreement, and maxim of sympathy) according to Leech in the short film "Ibu" on the YouTube channel Bakar Production to prevent inappropriate speech in communication. The method used in this study is qualitative descriptive with a pragmatic approach. The data collection technique used in this study is document analysis. The data analysis technique used in this study is flow analysis. The data validation technique used for this research is theory triangulation. The results of this study reveal the presence of 29 instances of adherence to Leech's politeness principles, encompassing all six maxims. By adhering to Leech's politeness principles in the film, it is hoped that society, especially teenagers, can emulate polite language in the film and apply it in their daily communication.
Nilai Kearifan Lokal dalam Tradisi Anggara Kasih Patirtan Cabean Kunti
Authors: Setiani Eka Novi , Waluyo Budi , Veronika Prima
Published: September 2024

The Anggara Kasih tradition ceremony is one of the local cultures which still carried out today because there are local wisdom values in it. This study aims to explain the local wisdom values that exist in the Anggara Kasih Patirtan Cabean Kunti tradition and its relevance as Javanese teaching material in junior high school on the basic competencies of analyzing descriptive texts about regional traditional ceremonies. The data obtained in this research is qualitative data in the form of interviews. The sampling technique used in this research is snowball sampling. Data collection was done with three techniques, namely observation, interview, and document analysis. The technique used for validity testing is triangulation of data sources. The data analysis technique used the Miles and Huberman interactive model. The results of the research that have been conducted can be concluded as follows: (1) the local wisdom values contained in the Anggara Kasih tradition are: religious values, social values, cultural values, and environmental protection values; (2) the Anggara Kasih tradition carried out in Cabean Kunti village has relevance as teaching material in junior high school because it has four aspects, including: divine aspects, social aspects, cognitive aspects, and skills aspects. The results of this study are expected to be a reference for teachers to choose teaching materials about traditions that exist in their own area and be able to motivate students to study hard because they know firsthand the implementation of these traditions.
Analisis Kelayakan Isi Buku Teks Wursita Basa Kelas IX SMP
Authors: Padmawati Anggita Dwi , Suhita Raheni , Veronika Prima
Published: September 2024

Abstrack

This research aims to describe the feasibility of the contents of the Javanese Wursita Basa textbook for class IX SMP/SMPLB/MTs published by CV. Friends This research uses a qualitative descriptive approach. Data analysis techniques use interactive analysis, namely data collection, data reduction, data presentation, and drawing conclusions. Content feasibility data and language feasibility are analyzed with instruments compiled based on relevant theories and information and assessments from several sources. Data validity test using researcher and theory triangulation. In triangulation, researchers involved other researchers, namely Dewinta Enha Putri (DEP). Content eligibility is reviewed from the appropriateness of the material, accuracy of the material, and the content of the learning material, while language eligibility is reviewed from the appropriateness of the language with the level of development of the students, communicative, as well as the sequence and unity of ideas. From the results of the analysis, it can be concluded that the feasibility of the content of the Wursita Basa Javanese textbook obtained a percentage of 79.6% from the average score of 25.5 and a maximum score of 32
Keywords: textbook, contents feasibility, curriculum of 2013
Symbolic Meaning in Tradition The Malem Selikuran of Keraton Kasunanan Surakarta Hadiningrat, Indonesia
Authors: Zuhri Moh Sayful , Wardhana Ivan Prapanca
Published: September 2024

Culture in Indonesia is very diverse, including Javanese culture. This culture developed through the acculturation process that occurred in Javanese society. Each culture has its own meaning or symbolism which is usually connected between humans and God. The Malem Selikuran di Keraton Kasunanan Surakarta Hadiningrat tradition has quite a broad meaning. This tradition is not only a celebration, but also has meaning contained in it, for example a means to strengthen a Muslim's faith, strengthen ties of brotherhood, and preserve culture. In today's life, it is important to maintain unity, respect existing diversity, and to always be grateful for the blessings that God has given. This research is qualitative research with an ethnographic approach. This approach is used because the ethnographic approach focuses on sociological meaning through field observations of sociocultural phenomena, so that the data obtained is quite clear. The results of this research are in the form of symbolic meaning contained in the traditional activities of the Malem Selikuran in the Keraton Kasunanan Surakarta Hadiningrat.
Strengthening Aswaja An-Nahdliyah to Anticipate Radicalism for Islamic Education Teacher Candidates
Authors: Jazil Saiful , Fahmi Muhammad , Hunaida Wiwin Luqna , Rohman Fathur , Djazilan M. Sukron , Prasetia Senata Adi , Sholihuddin Muh. , Mas'ud Ali
Published: September 2024

This article examined the strengthening of Aswaja An-Nahdliyah’s understanding as an effort to anticipate radicalism for Islamic education teacher candidates at the Faculty of Tarbiyah, Sunan Ampel State Islamic University Surabaya. The type of this article was qualitative with a Participatory Action Research approach and the method of extracting initial condition data and coaching related to Aswaja An-Nahdliyah material as an effort to anticipate radicalism for Islamic education teacher candidates in the fifth semester of the Academic Year 2021-2022. The results demonstrated that strengthening Aswaja An-Nahdliyah provides an understanding of the map of radical groups and movements; Aswaja An-Nahdliyah teachings and attitudes teach religious moderation as a basis for anticipating and avoiding radicalism teachings and attitudes; Aswaja An-Nahdliyah’s teachings are full of religious tolerance, which helps to block radicalism. This issue is very important considering that even though Sunan Ampel State Islamic University Surabaya, as an Islamic university, is not free from radical infiltration, strengthening Aswaja is necessary to anticipate this, especially for Islamic education teacher candidates.
Improvement of Fibrous Dysplasia After Burosumab Therapy in a Pediatric Patient with McCune-Albright Syndrome
Authors: Sawamura Kenta , Hamajima Takashi , Kitoh Hiroshi
Published: September 2024

Case:

Burosumab is a novel drug developed to treat hereditary fibroblast growth factor 23 (FGF23)-related disorders. We report the case of an 11-year-old girl with McCune-Albright syndrome (MAS) who sustained hypophosphatemia due to excess FGF23 and multiple bone lesions of fibrous dysplasia (FD). Burosumab therapy markedly improved not only the biochemical parameters but also the radiographic appearance of the FD lesions and clinical symptoms.

Conclusion:

This is the first report to demonstrate that burosumab is effective in improving FD lesions in a patient with MAS.
La funcionalidad turística aplicada a Geoparques Mundiales de la UNESCO: los casos de Mixteca Alta (México) y Villuercas-Ibores-Jara (España)
Authors: Pareja-Pareja Germán , Fernández de Castro Martínez Gonzalo , Barrera-Fernández Daniel , Martínez-Ibarra Emilio
Published: September 2024

Los Geoparques Mundiales de la UNESCO, a pesar de su gran diversidad patrimonial, no han sido objeto de estudios de funcionalidad turística. Estos estudios se han centrado principalmente en las Ciudades Patrimonio Mundial y en el patrimonio cultural inmueble y, en menor medida, en los recursos naturales, siendo los geológicos los menos analizados debido a su reciente reconocimiento. En este artículo se realiza el estudio de funcionalidad turística de dos geoparques que presentan realidades muy dispares, uno latinoamericano (Mixteca Alta) y otro europeo (Villuercas-Ibores-Jara), con el objetivo de visibilizar la gestión de geoparques bajo diferentes realidades a nivel mundial. La metodología empleada consiste en un inventario pormenorizado del patrimonio existente, identificando el uso turístico de cada recurso patrimonial y otros indicadores de interés para su funcionalidad. La base del inventario ha sido fruto de una selección de fuentes de información, algunas de ellas cedidas por ambos geoparques, así como de trabajo de campo. Los resultados de este trabajo proporcionan un análisis de la funcionalidad turística en dos casos exitosos de geoparques que presentan diferentes formas de gestión acorde a su realidad. De igual forma, se proponen actuaciones para mejorar, si cabe, la gestión turística sostenible de los recursos patrimoniales de estos territorios.
Reconnaissance-Strike Tactics, Defeat Mechanisms, and the Future of Amphibious Warfare
Authors: Friedman B. A.
Published: September 2024

Professional discussions of tactics tend to revolve around debates over “strategies” of maneuver versus attrition, ongoing discussions of revolutions in military affairs, and proposals for new concepts of operation. What these discussions are really about though is tactics, specifically what kind of tactics are appropriate for the modern operating environment. Active-duty practitioners have little time to think deeply about tactics due to the intense demands of training to execute doctrine, which are codified tactics that have worked in the past but may not be sufficient to adapt to changing and uncertain situations in combat. Fortunately, with a little focus on tactics we can cut through the hype as all of these ideas have been circling around the identification of the modern tactical regime: reconnaissance-strike tactics. This article first reviews the current debate about maneuver versus attrition tactics and propose that, instead, the advent the reconnaissance-strike regime demands a more sophisticated examination of tactical principles applied against defeat mechanisms. Lastly, it examines implications for amphibious warfare and the Marine Corps generally.
Oceans Are Now Battlefields: How the U.S. Navy and Marine Corps Can Counter North Korea's Navy in an Evolving Age
Authors: Cunningham Alan
Published: September 2024

The North Korean armed forces are one of the main threats in the Asian geographic region and consistently have been a thorn in the side of Western allied Asian nations and the United States. In such a conflict with the North Koreans, the United States would, alongside others, take a lead role in countering North Korean naval forces. Taking into account the Force Design 2030 and 2045 battleplans devised by the U.S. Navy and Marine Corps, it is imperative to explore how the United States could work to combat North Korean forces in the near future. With the Force Designs and stated modernizations and improvements being performed in sea-based warfare, there is much more to do to make a strong military force that can strike against the North Koreans.
China's "Second Battlefield": Political Warfare in Combat Operations
Authors: Gershaneck Kerry K.
Published: September 2024

This article addresses how the People’s Republic of China (PRC) will conduct political warfare against the U.S. Marine Corps in combat operations. The PRC has inextricably intertwined political warfare in its naval and maritime strategies to set the conditions for success in such a kinetic war. If the PRC perceives that political warfare alone will not achieve its goals, it threatens to achieve them through armed conflict, which may result in U.S. Marine Corps operations as a counter. This article examines key aspects of PRC political warfare in combat operations, to include a brief historical overview; goals, objectives, strategies, and tactics employed; targeting of U.S. and allied combat units, military base communities, and overseas Chinese; and the likely progression of political warfare operations throughout the combat campaign.
Selecting San Carlos: The Falklands War, 1982
Authors: Maus Michael T.
Published: September 2024

During the Falklands War in 1982, the United Kingdom conducted an amphibious landing to repossess the Falkland Islands from the invading Argentinians. The Falkland Islands naturally possess thousands of miles of shoreline and more than two dozen suitable beaches for an amphibious landing with several in close proximity to the United Kingdom’s primary objective of Stanley. However, British forces landed in the San Carlos Water, a bay across East Falkland Island miles from their objective all the while short of tracked vehicles and helicopter transports and pressured by the approaching onset of the Southern Hemisphere’s winter. This article analyzes why British task force planners selected the San Carlos inlet for an amphibious assault and what parameters and events bound or persuaded planners to make their final decision. This article contributes to the operational analysis historiography of the Falklands War by examining the reasoning of selection and further supplements the historiography on the British way of war with regard to amphibious operations.
Unlocking Engineering Solutions for Handling a Complex Mix of KHI, MEG, Corrosion Inhibitor, and Produced Water
Authors: Nengkoda Ardian
Published: September 2024

The compatibility of KHI and MEG, chemicals used to inhibit gas-hydrate blockage, with corrosion inhibitors (CI) and produced water is a significant concern in the oil and gas industry. Consequently, pipeline integrity, flow assurance, and safely produced water management are critical. This paper highlights an innovative engineering approach based on extensive lab testing and field study that can resolve a complicated mix of KHI, MEG, CI, and produced water. A field sampling was conducted to assess the severity of the mixing of KHI, MEG, and CI and the water produced in the production stream. The tests were conducted at temperatures 35 and 65 oF to reflect summer and winter operations, including the dissolve tendency. The pressure was constant at 70 psi, and the soaking time was 24 hours. Core flood tests were performed using reservoir core plugs to study the compatibility. The incompatibility of KHI, MEG, CI, and produced water was discovered, and the resultant sludge was found to be soluble in distilled water and HCl acid but insoluble in Xylene and Diesel. The core flood test revealed that adding 1,000 ppm of KHI to water will cause the original core brine permeability to decrease by around 13%. There will be a slight decrease in these mixes when the MEG and CI are added. Injection of nearly 7 pore volumes of 7 wt% NaCl brine was able to remove the created damage. The blending of all chemicals with produced water showed less damage (almost 8%) compared to that of KHI alone. Based on this test, the engineering solution is derived from the segregation of the KHI as soon as possible before mixing it with the rest of the water. Therefore, new pipelines, buffer tanks, transfer pumps, and filtration systems are required.
60 Years of UUU Fields – Leveraging on Big Industry Technology Applications for Rejuvenating the Foremost Niger Delta Condensate Gas-Development Asset
Authors: Osode P. I. , Soro A. O. , Ebufegha A. J. , Aworanti O. A. , SamaiIa I. A. , Shehu A. H.
Published: September 2024

The UUU cluster is the largest condensate gas producing (peak rate - 400 MMscf/d) asset in onshore Western Niger Delta. It comprises UghE, UghW and UtoR (UUU) dual hydrocarbon production fields which were discovered in 1959, 1960 and 1964 respectively. In the last decade, field redevelopment campaign which was premised on extensive integrated sub-surface studies was initiated to rejuvenate the asset and increase production target to 0.5 Bscf/day.

Gas condensate is contained in high-permeability (150 – 1,000 md) sandstone reservoirs between 8,000 and 15,000 ft subsea depth. There are a total of 14 producing gas wells with 15 producing intervals (including one dual string, dual completion). Three gas processing plants with nominal capacities of 360 MMscf/d, 150 MMscf/d and 90 MMscf/d are utilised to process the produced wet gas prior to export for domestic and West African consumption. The proximity of the producing gas fields created an excellent opportunity for integrated production operations management, surface facilities sharing and cost optimisation. In the aftermath of the 2012 western asset ownership transfer from Shell Nigeria, attention was focused on maintaining optimal production targets through the following activities:

Execution of in-fill development opportunities within the cluster Recovery of production from matured "locked-in" reserves Production facilities revamp and integrity management Deployment of cost-effective processes and new technology applications for CAPEX and OPEX reduction

The asset management activities included successful deployment of seismic data reprocessing and interpretation, new well drilling and workovers, integrated asset modelling and management processes, flow assurance and well integrity management activities, surface facilities debottlenecking, advanced data acquisition campaign including multi-phase flow metering, and other low-cost, well intervention retrofit applications. All these efforts have resulted in sustained natural gas production of over 300 MMscf/d with associated 5,000 bpd of condensate in the past decade.

This paper describes how UUU fields condensate gas development and production performance has evolved over the past 60 years; the well, reservoir and facility management challenges encountered along with the big industry technology applications adopted for sustained production. It is expected that this paper will shed light on those elements that are critical to sustaining production in analogue brown fields.
Application of an Ensemble Based Method for Pressure-Rate Deconvolution
Authors: Piccinini R. B. , Kubota L. K. , Galvão M. R. , Emerick A. A.
Published: September 2024

This paper employs an ensemble-based method to address and assess the uncertainty in solutions to the single- and multi-well pressure-rate deconvolution problem. The method is implemented in two field cases from the Campos Basin. The first field case comprises a single vertical well producing from a virgin reservoir with continuous recording of bottom-hole pressure but uncertain flow-rate history. The second field case comprises a pair of horizontal wells, one acting as a producer and the other as an injector, with similar uncertainties in the flow-rate history and the additional complexity of a multi-well problem. We extend the investigation into the solution of the pressure-rate deconvolution proposed in a previous work (Kubota and Piccinini, 2022), which relies on the fundamental solution of the diffusion equation for bounded domains. In the present study, the deconvolved pressure response is obtained using the Ensemble Smoother with Multiple Data Assimilation (ES-MDA), a popular method for history matching numerical reservoir simulation models. ES-MDA provides an uncertainty quantification of the deconvolved pressure response and the investigated porous volume, along with other reservoir properties. Because ES-MDA uses a Bayesian formulation, data are weighted according to the inverse of the error variance. We explore this feature to include data from flowing periods, a desirable feature for the analysis of long-term pressure data with few well shut-ins. The results obtained for the two field cases consist of the posterior ensemble of model parameters, estimated flow rates, investigated pore volume, productivity index, single-well deconvolved response, as well as interference responses for the multi-well case.
Hydrogen Mixing Dynamics in Depleted Gas Reservoirs
Authors: Li Dexuan , Emami-Meybodi Hamid
Published: September 2024

Depleted gas reservoirs are suggested as a suitable choice for the seasonal storage and utilization of hydrogen (H2) with the presence of surface infrastructure, large storage capacity, and available history data. However, hydrogen mixing with in-situ natural gas and cushion gas leads to contamination and subsequent loss of hydrogen. Hydrodynamic dispersion is an important driving mechanism for gas mixing during cyclic hydrogen injection/withdrawal. Accordingly, we investigate the mixing dynamics of hydrogen, cushion gas, in-situ gas, hydrodynamic dispersion, and formation geometry and their impacts on the recovery factor and purity of back-produced hydrogen. We construct a numerical model based on the finite-element method considering hydrodynamic dispersion. The model is then utilized to examine the mixing dynamics of injected hydrogen under various geological and operational parameters. The results reveal that the amount of injected cushion gas and in-situ significantly influences the purity of produced hydrogen. As the cushion and in-situ gas amount increases, the H2 purity, as well as the H2 recovery factor, decreases in each withdrawal. With the equivalent molar composition, the hydrogen recovery factor using in-situ gas as cushion gas is slightly better than using injected N2 as cushion gas in each cycle. The hydrodynamic dispersion negatively impacts the produced H2 purity due to the expansion of the mixing region, leading to H2 contamination and a reduced recovery factor. The hydrogen recovery factor will drop 1-2% when longitudinal dispersivity is at 10−1 – 10° orders, however, it will drop 3-6% when longitudinal dispersivity is at 101 orders. However, compared with cushion and in-situ gas amount, the hydrodynamic plays a minor role in the performance of underground hydrogen storage. The anticline geometry can utilize gravity segregation to facilitate the withdrawal of H2. Compared with anticline geometry, the H2 recovery factor of a horizontal geometry will drop 17% - 23% in each cycle.
Evaluation of Acoustic Sand Monitors in Multiphase Flow Production for Small Sand Particle Sizes
Authors: Nadeem Asad , Hasan Mubashir , Vieira Ronald E. , Shirazi Siamack A.
Published: September 2024

Sand production in oil and gas wells and erosion of pipelines and fittings caused by sand impact is one of the most common and expensive problems for the oil and gas industry. Acoustic sand detectors (ASD) are commonly used to provide a warning/alarm when sand is being produced in pipelines. For acoustic sand detectors to be very effective, it is necessary to know threshold sand rates (TSR), that is the lowest sand rate at which detectors will fail to recognize and differentiate between background noise caused by flow and noise created by sand particles impacting pipe walls. A broad range of multiphase operating conditions has been experimentally investigated with acoustic sand detectors in large scale flow loop facilities to evaluate the effectiveness of acoustic sensors for very small sand sizes entrained in multiphase flow. New experiments were performed using 101.6 mm pipe diameter standard stainless-steel elbow, with different combinations of superficial velocities, ranging from 5 m/s to 30 m/s for gas and 0.1 m/s to 0.3 m/s for liquid using very small particle sizes 25 μm, 50 μm, 75 μm and 300μm. Two different acoustic sand detectors were installed downstream of the elbow. These results are compared to the previously obtained test results on smaller diameter test sections. Various flow regimes are studied including annular, churn, stratified and slug flow.

For the 101.6 mm ID test loop data for various flow conditions, in horizontal orientation, with 25 μm sand, the sensors were not effective in detecting the sand noise impacting an elbow due to the high noise generated by the multiphase flow impacting the elbow. On the other hand, for the smaller pipe diameter of 76.2 mm, during previous studies, the sensors were able to detect the 25 μm sand particles under similar flow conditions. Also, it was observed that with increasing the sand size, TSR value decreased. Additionally, it was observed that for 101.6 mm ID pipe flow with high gas velocities, the TSR is lower compared to the conditions where the gas velocity is low as the flow regime is changed from stratified to annular in horizontal flow and from annular to annular-churn for vertical flows. The highest TSR was observed for annular flow condition in horizontal orientation. The results from this work can help operators to understand that under what conditions acoustic detectors can detect and distinguish sand impact noise from the background flow noise in multiphase flow and what is the estimated TSR. Thus, greater assurance is provided to operators for optimizing oil and gas production rates, especially in wells that have a tendency to produce sand.
Modeling and Analysis of Pressure- and Rate-Transient Behavior of Interfering Horizontal Wells in Multi-Layer Unconventional Reservoirs
Authors: Makhatova M. , Ozkan E.
Published: September 2024

Multi-well systems are essential for unconventional asset development by optimizing the reservoir drainage, well productivity, and cumulative recovery to maximize the economics of the project. Although the underlying principles of infill drilling and multi-well production is the same as that for conventional reservoirs, in unconventional reservoirs, the contrast between the stimulated and unstimulated volumes (SRV and ORV, respectively) of the reservoir, differences in well completions and resulting SRV vs. ORV properties, asynchronous start of production, different production conditions, and unmatching schedules of production and shut-in periods further complicate the design (the spacing, completion, and production conditions) of the multi-well systems. Moreover, development decisions are usually made with uncertainties caused by the complexity of well-interferences in the existence of extreme reservoir heterogeneity. Therefore, to make multi-well unconventional reservoir development decisions, both the knowledge of the interwell reservoir characteristics and their effect on the multi-well productivity of the system must be known. These requirements call for models that are accurate and efficient for estimating reservoir and completion parameters by pressure- and rate-transient analysis (PTA and RTA, respectively) and capable of efficiently evaluating multiple development scenarios subject to the uncertainties of reservoir characteristics.

We have developed robust semi-analytical models to analyze the performances of multi-well systems in single and multi-layer completion conditions in unconventional reservoirs. This paper discusses the diagnostic features of pressure- and rate-transient behaviors of multiple wells in single- and multi-layer unconventional-reservoir, delineates the sensitivities of well performances to well spacing, stimulation treatment, and production conditions of interfering wells, and demonstrates the application of the models to PTA and RTA of field cases. The PTA/RTA methodology presented in this work consists of obtaining initial estimates of the well completion and reservoir properties through diagnostic and straight-line analysis of specific flow regimes, guided by the multi-well solution, and refining the estimates by matching the transient well responses by the semi-analytical model. This methodology provides a remarkably efficient and reasonably accurate estimation of properties within the bounds of the system uncertainties.
Trends in Academic Research and Graduate Education in Petroleum Engineering Programs
Authors: Fahes M. , Al-Shalabi E. W. , Hoffman T.
Published: September 2024

Undergraduate education in Petroleum Engineering (PE) has survived the latest downturn in the industry, and enrollment has started to show an uptick in numbers. Anecdotal evidence, however, has been hinting at a different trend in graduate training and academic research. In this work, the authors collected and analyzed data, on US-based petroleum engineering departments, that included over $137M in external research funding and over 1,900 thesis/dissertations over the span of ten years, in addition to over 1,100 publications from these departments in 2023. The data was analyzed through classification into different categories, including Reservoir/Production, Fracturing, Drilling, Non-Fossil Fuel Geoenergy (geothermal, CCS/CCUS, hydrogen), and Others. The results reveal a drastic shift in research and graduate training that is expected to significantly impact the future of these departments and the workforce they train. The findings show a drop of 70% in external funding supporting oil and gas research over the past ten years, and a growth of 230% in funding for non-fossil fuel topics. This transition is shown to have impacted the topics represented in theses, dissertations, and publications. The findings call for strategic discussions around alignment between the needs and the trajectories in this domain.
Research on the Influence of Natural Fracture Development on the Deep Shale Gas Well Fracture Network Construction in Southern Sichuan
Authors: Peng Sirui , Zhao Jinzhou , Ren Lan , Lin Ran , Zhou Bo , Wu Jianfa , Song Yi , Shen Cheng
Published: September 2024

The Sichuan Basin, China's largest shale gas development region, encompasses the natural fracture-rich Luzhou Block. The high-density non-uniform natural fractures in this area significantly influence the construction quality and efficiency of deep shale gas horizontal wells. Research indicates that the mechanical properties and spatial distribution of these natural fractures affect the propagation and diversion of hydraulic fractures, but the governing laws remain to be fully elucidated. This study categorizes the Luzhou Block's naturally fractured areas into six types based on their development characteristics and relative positions to horizontal well sections. Furthermore, it introduces a method for morphological inversion of shale gas well fracture networks using microseismic monitoring data. This method was applied to 24 deep shale gas wells in the Block and combined with the six types of naturally fractured areas, the above underlying influence mechanism was derived. Then it reveals how naturally fractured areas with different characteristics influence the fracture network morphology and complexity and analyzes the relationship between fracture network quality and well production. The results demonstrate that during the hydraulic fracturing process in deep shale gas reservoirs, the development areas of natural fractures can capture or intercept the fracture network, obstructing its expansion behavior, reducing its area and complexity, and ultimately leading to a decrease in gas well production. In particular, when a small-angle, large-scale naturally fractured area develops near the wellbore, the hydraulic fractures will quickly propagate to this area. After activating and communicating the natural fractures, it may cause rapid fluid filtration and a sharp drop in the net pressure within the fractures, severely impacting stimulation performance. It suggests that adjusting construction parameters appropriately may mitigate the adverse impact of natural fractures on the fracturing effect. These findings clarify how naturally fractured areas with different development characteristics affect stimulation performance and offer insights and references for designing and optimizing deep shale gas well fracturing technology.
ScCO2 Foams for Geothermal Reservoirs’ Stimulation: Impact of Fracture Roughness and Temperature on Rheology
Authors: Samarkin Yevgeniy , Prodanovic Maša , DiCarlo David , Tajik Abdul Raouf , Wileman Angel
Published: September 2024

Applications of foams as fracturing fluids have gained a significant interest over the past few decades. Foams possess several advantages over regular fracturing fluids, such as flexible rheology, better mobility control, and reduced water utilization. While the flow of foams in porous media has been extensively studied, their performance in fractures remains partially unclear. This research aims to expand this knowledge and discuss potential applications of foams for the controlled stimulation of geothermal reservoirs.

The experimental work for this study involved utilizing granite rock samples, saw-cut into halves to mimic fractures. A spacer was used to keep smooth fractures open during experiments, while rough fractures were generated by modifying the rock surface using a sandblasting technique. The performance of the supercritical CO2 (scCO2) foam (65-90% quality), represented by its viscosity, was tested in rough and smooth fractures at 1200 psi pressure and temperatures ranging from 90°C to 150°C via multiple core flood experiments.

The study revealed that foam viscosity drops considerably as temperature rises, with a reduction of over 2-fold observed beyond 90°C. Additionally, foamability decreased at higher temperatures, resulting in less and weaker foam at the same flow rates compared to lower temperatures. However, injecting foam at higher flow rates improved foamability at elevated temperatures. Moreover, the roughness of fractures had a positive, though less significant, impact on foam rheology than anticipated. In some cases, roughness improved foam generation, while in others, smooth fractures yielded better results.

The outcomes of this study provide more detailed insights into the performance of foam under high-temperature conditions. A better understanding of foam behavior in rough and smooth granite fractures at high temperatures further expands its potential applications in geothermal reservoirs for controlled stimulation.
Barrier Design and Evaluation Process to Achieve Cement Integrity in CCS Wells
Authors: Jandhyala Siva Rama Krishna , Lewis Samuel J.
Published: September 2024

Barrier design processes for oil and gas wells have historically demonstrated their benefit in risk reduction and cement design optimization when using Portland cement. Carbon Capture and Sequestration (CCS) wells have a different set of risks which must be considered. These risks are a consequence of mechanical, thermal, and hydraulic loads acting on the barrier which is also undergoing mechanical changes due to chemical alteration in the case of Portland cement. Such changes are a function of time, CO2 state, cement composition, temperature, and pressure. The specifics depend on the use case, for example a plug, an annular sealant, a monitoring well, or an injection well. The goal of any risk assessment is to determine whether the above-mentioned events will compromise the barrier. Given the chemical and mechanical changes occurring in a Portland cement barrier, there is a need to tailor existing barrier design processes to suit CCS wells and account for this alteration.

The proposed design process comprises of four steps. The first step will assess the extent of the reaction between CO2 and the cement sheath under downhole conditions. The second step will determine the reaction driven changes to the mechanical properties of the cement sheath. Such changes may occur throughout the cement or only in a portion of cement depending on the location and injection plans. The third step will use the modified properties and determine the stresses and temperatures in the cement sheath under the action of temperature and pressure loads. The fourth step will determine the risk of mechanical failure by calculating operational loads and applying them to the altered cement. If the failure risk is too high, the cement composition can be iteratively tailored to determine an acceptable design.

The first two steps are enabled by experimentally generating CO2 exposure data on multiple cement systems and exposure conditions. Data for alteration rates, physical changes, mechanical changes, etc. are gathered in order to build semi-empirical models that can predict the effect of CO2 based on the cement system design over time. The third step utilizes existing wellbore stress modelling software and incorporates the spatially varying mechanical property inputs determined by the alteration models. Stresses from the third step are compared with predicted failure properties (compressive and tensile strengths) to assess the risk of loss of cement sheath integrity.

The proposed design evaluation process describes the chemical and mechanical events unique to CCS wells. Consequently, it will provide a vital tool to the industry for tailoring cement compositions and minimizing risk of loss in cement sheath integrity in a dynamic CO2 environment.
The Effect of Fluid Content and Effective Stresses on Stick-Slip Friction in Rocks: Implications for Induced Seismicity
Authors: Sathyanath Arun , Sharma Mukul M.
Published: September 2024

Induced seismicity has become a serious issue in many unconventional plays in the US. These events are primarily associated with the injection of large quantities of produced water at very high rates. It is well known that the frictional properties of rock joints have a large influence on such induced seismic events during wastewater disposal in sub-surface formations. The primary objective of this study is to understand the role of pore fluids, in-situ stress, fracture roughness and pore pressure on the shear failure of rock fractures.

A new triaxial apparatus is developed that allows us to measure the frictional properties of fractures under different loading and pore pressure conditions. This apparatus can independently control the pore pressure, shear stress, and normal stress acting on the fracture surface. The frictional properties of rocks and the fracture permeability after a slip event were estimated by keeping the net shear stress and normal force applied on the rock constant. The experiments conducted allow us to directly measure stick-slip and dynamic friction coefficients as well as the creep that occurs after frictional sliding. Tests are conducted with both air and brine as pore fluids. The shear stress is gradually increased, and the displacement of the fracture surfaces is measured. The effective normal stress and pore fluid are varied to measure the impact of these parameters on both stick-slip and creep frictional sliding.

The results from the experiments clearly show that the rock surfaces slide in a combination of sudden jerky motions (stick-slip events) and of smooth, gradual movements (creep deformation). The frequency and magnitude of the stick-slip events are important since it is these events that are primarily responsible for induced seismicity. Changes in the effective normal force acting on the fracture mimics the change in pore pressure with water injection. When the shear stress acting on the fracture surfaces overcomes the strength of asperities preventing the sliding, stick-slip sliding begins followed by smooth sliding. Creep deformation is measured as the shear stress and the pore pressure are held constant and the fracture surfaces continue to slide.

The coefficient of friction gradually increases as the shear stress increases and the surfaces repeatedly slide over each other. The friction coefficient reaches a plateau value of about 0.6. The effective normal stress or the type of pore fluid has very little influence on this stabilized value of friction coefficient. The friction coefficient appears to be primarily controlled by the roughness of the fracture surfaces. The number and magnitude of stick-slip events is significantly larger when air is the pore fluid (rather than water). This clearly implies that the composition of the pore fluid impacts the likelihood and magnitude of induced seismicity. The magnitude of the stick-slip events also increases as the effective confining stress increases.
Unconventional Solutions to Cure Severe-Total Lost Circulations – Field Applications from Middle East
Authors: Savari Sharath , Kerkhoff Erik , Ismail Ahmed , Nasrallah Mena , Bashandy Tamer
Published: September 2024

Curing severe to total lost circulation in naturally fractured/vugular formations has always been challenging, especially across the Middle East. In these environments, conventional particulate lost circulation materials (LCMs) are seldom effective due to the uncertainty on the sizes of the formation openings through which losses occur. This paper presents lab evaluation data, supported by field experience, of using a combination high fluid loss squeeze (HFLS) and reticulated foam LCM (RFLCM) treatment.

The LCM treatment was designed and qualified based on successful laboratory tests sealing slots up to 40,000 microns. Laboratory and field results are presented from the dual HFLS and RFLCM technology application in two countries in the Middle East: Oman and United Arab Emirates (UAE). The details include formation characteristics, hole size, LCM pill volume and concentrations, and the mixing and pumping methodologies used. The success of the applications is demonstrated by presenting the loss rates before and after applying the treatments, in static and dynamic wellbore conditions, and illustrates savings in terms of rig time.

In Oman, the subject wells experienced static losses up to 125 bbls/hr and dynamic losses in the range of 280 bbls/hr (at 550 gpm) to "No returns". The formation was characterized as vugular, and the client's objective was to pump an efficient LCM solution that would cure losses quickly after reaching well Total Depth (TD) and perform logging operations without having to use a cement plug thereby saving rig time. The HFLS and RFLCM treatments were mixed in water, pumped through a circulating sub and a hesitation squeeze was applied. After the squeeze, both static and dynamic loss rates reduced to zero and operations were able to safely continue.

For the UAE applications, the subject wells were drilled with non-aqueous fluid and losses experienced were in the range of 85-200 bbls/hr in static conditions, and 150 bbls/hr to complete losses in dynamic mode (990-1250 gpm). The formation was characterized as naturally fractured. The HFLS and RFLCM components were mixed in base oil, pumped through a circulating sub and a hesitation squeeze method was applied. After the squeeze, static losses reduced to 2-15 bbls/hr and dynamic losses to a maximum of 25 bbls/hr (dropping down to 5 bbls/hr while drilling) allowing operations to recommence.

In technical qualification tests, plugging of a 40,000-micron lab-simulated fracture/vug opening provided confidence that the subject LCM combination would deal with losses to uncertain fracture/vug size downhole. The successful field applications where severe to total losses were cured has validated the HFLS / RFLCM dual approach. The most notable advantage of improved LCM technology is the reduction in well construction costs through decreased rig time associated with curing severe to total lost circulation.
Determination of Production Potentials of Geothermal Resources for Rapid Exploration and Development Decisions
Authors: Jin Guodong , Kwak Hyung T , Yousef Ali A , Banaja Hussam H
Published: September 2024

This paper presents a semi-analytical wellbore heat flow model coupled with a formation heat conduction model for rapidly determining output potentials of thermal energy from the open-loop and closed-loop geothermal systems. Energy conservation equations are used to simulate thermal flow dynamics of fluids inside the wellbore, while heat diffusion equations govern the transient heat transfer in the formation. A semi-analytical technique is used to solve these coupled equations iteratively. Model validation was done by comparing the semi-analytical solution with numerical simulation results on a 3D wellbore model for a coaxial closed-loop geothermal system. Good agreement of the temperature profile along the wellbore was observed between the semi-analytical and numerical results.

Production potentials of thermal energy depend on the geothermal systems selected to extract the heat from the reservoir. Closed-loop systems rely on the circulation of a working fluid to absorb and transport heat to the surface. Their heat extract efficiency depends on the mass flow rate and initial injection temperature of the working fluid. The higher flow rate leads to a lower fluid temperature but a higher thermal energy output at the wellhead. As the injection fluid temperature increases, the energy output decreases but the output fluid temperature increases. Open-loop systems produce the hot reservoir fluid directly to the surface, in which an increase in the flow rate would increase the fluid temperature and thermal energy production at the wellhead. As the production continues, thermal energy output decreases faster at the beginning and reaches a plateau in the long run. Compared to numerical models, the semi-analytical requires minimal inputs to generate the compatible outputs with higher computational efficiency, which is preferred in many applications, in particular for energy resource screen analyses of new geothermal prospects or repurposed oil and gas wells.
Reduce Costs by Improving Reliability and Extending Mean Time Between Failure MTBF in a Harsh Electric Submersible Pump-Lifted Field
Authors: Luis Enriquez , Carlos Reyes , Johanna Gallegos , Richard Torres , Gary Tagarot , E Batallas , Jorge Villalobos , Alvaro Correal , Juan Pancho , Kevin Andagoya
Published: September 2024

This paper presents a case study that includes the steps taken to improve the reliability of the artificial lift systems in a field of application. It is shown through the increase in the mean time between failures (MTBF) from 489 to 1,000 days and the decrease in the failure index from 0.47 to 0.24 over 5 years of continuous work.

An important challenge in the field of study was the high number of electric submersible pump (ESP) failures over 90 failures per year which caused losses over 500 Kbbl of oil per year and required around of 65 MMUSD to recover their production through workover activities. An integrated continuous improvement approach was applied by identifying the issues, proposing solutions and measuring results.

After the implementation of all the actions mentioned in this document, the MTBF was duplicated, the failure index was reduced 51% for ESP, 25% reduction in ESP-related production losses; plus 40% reduction in workover jobs which saves 26 MMUSD each year. Another benefit is reducing about 900 Tons of CO2 emissions thanks to less usage of diesel for workover jobs.

This document shows three sections which summarize: 1) The initial diagnostics, 2) Actions for improvement, and 3) Results. These three sections include four areas of focus: i) Data Management, ii) Culture and Organization, iii) Technology, and iv) Processes and KPI.

At the end of the document the reader will find the conclusions which show how a proper diagnostic can direct focused actions like the creation of a performance dashboard together with an organizational culture towards continuous improvement, and the associated benefits once the process is fully implemented.