bluuebunny/crossref_metadata_2025 huggingface dataset:
Indikator Biokimia untuk Identifikasi Anemia Defisiensi Besi di Indonesia
Authors: Helmyati Siti , Hasanah Fina Cahya , Putri Febriani , Sundjaya Tonny , Dilantika Charisma
Published: February 2024

Latar Belakang: Anemia merupakan salah satu masalah kesehatan yang ada di masyarakat, yang cukup banyak terjadi di negara berkembang khususnya Indonesia. Menurut World Health Organization (WHO), tiap tingkat usia memiliki potensial mengalami anemia, termasuk remaja usia 10-19 tahun. Melakukan deteksi dini atau skrining menjadi penting untuk dapat mengetahui lebih awal seseorang mengalami anemia defisiensi besi. Selain itu, dalam kerangka WHO untuk mempercepat penurunan angka anemia di dunia terdapat hasil yang ingin dicapai salah satunya yaitu dengan meningkatkan skrining anemia.
Tujuan: Tujuan dari literatur ini yaitu untuk mengetahui gambaran skrining melalui indikator biokima yang digunakan untuk identifikasi Anemia Defisiensi Besi di Indonesia.
Metode: Penelusuran literatur dilakukan pada database PubMed, Scopus, ScienceDirect, dan Garuda untuk literatur yang dipublikasi pada 2013-2023 sesuai panduan PRISMA. Artikel dikaji apabila berasal dari jurnal terindeks Scopus Q1-Q4 atau Sinta 1-Sinta 3 dengan desain penelitian eksperimental atau observasional yang dilakukan di Indonesia.
Ulasan: Melakukan skrining anemia pada wanita usia reproduksi untuk mengoptimalkan sintesis hemoglobin, mencegah kerusakan sel darah merah yang berlebihan, dan mengurangi kehilangan darah. Berbagai teknik skrining anemia telah dikembangkan di berbagai negara dengan mempertimbangkan metode yang terjangkau, mudah digunakan, dan non-invasif dibandingkan dengan metode invasif yang biasa digunakan. Banyak faktor yang perlu dipertimbangkan ketika memilih pengukuran Hb di laboratorium klinis atau lapangan termasuk kebutuhan kendali mutu (QC), kondisi ekstrim di lingkungan, kekurangan sumber daya di lingkungan, standar pelatihan yang tidak sesuai, dan kondisi ekstrim di lingkungan. Risiko dampak negatif Pengukuran Hb dapat dikurangi dengan mempertimbangkan berbagai faktor. 
Kesimpulan: Di Indonesia, skrining masih sering menggunakan teknik invasif untuk mendeteksi anemia. Ini melibatkan pengambilan sampel darah vena atau kapiler dan pemeriksaan darah lengkap untuk mengukur kadar hemoglobin dalam darah melalui laboratorium.  Berbagai negara telah mengembangkan metode skrining anemia yang lebih murah, mudah digunakan, dan non-invasif daripada metode invasif yang biasa digunakan. Alat penilaian yang dapat diandalkan untuk mengukur dan menafsirkan konsentrasi Hb diperlukan untuk mencapai tujuan global sebagai upaya mengurangi anemia dan mengevaluasi efektivitas intervensi.
Kata kunci: anemia, defisiensi zat besi, prevalensi, remaja, Indonesia
Book Review: The Peregrine Falcon
Authors:   University of New England Armidale, NSW, Debus Stephen
Published: February 2024

n/a
AI-Based Tree Species Classification Using Pseudo Tree Crown Derived From UAV Imagery
Authors: Miao Shengjie , Zhang Kongwen Frank , Zeng Hongda , Liu Jane
Published: February 2024

Urban tree classification is pivotal in urban planning and management, facilitating informed decision-making processes. In this study, we introduce a novel data presentation method termed Pseudo Tree Crown, designed to enhance the accuracy and efficiency of urban tree classification. Leveraging the latest advancements in artificial intelligence (AI), we employ a state-of-the-art classification scheme, PyTorch, to maximize the accuracy of tree classification. Our results demonstrate a robust classification accuracy of over 95% from high spatial resolution imagery from Unmanned Aerial Vehicle (UAV), underscoring our proposed approach’s effectiveness. Moreover, the adaptability of our method renders it applicable to various study areas, highlighting its versatility and potential for widespread implementation in urban planning and management initiatives.
Is Biomethane Production from Common Reed Biomass Influenced by Treatment Wetland Hydraulic Parameters?
Authors: Sciuto Liviana , Licciardello Feliciana , Barbera Antonio Carlo , Scavera Vincenzo , Musumeci Salvatore , Severino Massimiliano , Cirelli Giuseppe Luigi
Published: February 2024

Treatment wetlands (TWs) are Nature-Based Solutions increasingly used worldwide for wastewater (WW) treatment able to remove mineral and organic pollutants through both physical and biochemical process. Besides the reusable effluent, the TWs produce as main output plant biomass that need to be harvested and disposed at least once a year with significant management costs and TW temporary out of service. This study aims (i) to evaluate the potential of TWs biomass for local energy production and (ii) to understand TW hydraulic conductivity (Ks) effects on the biomass biomethane yield. Specifically, it was addressed by determining the Biochemical Methane Potential of common reed (CR) (Phragmites australis) samples collected at three harvest times from the 10-years-old horizontal subsurface treatment wetland (HSTW) used as a secondary WW treatment system for the IKEA® store located in Catania (Eastern Sicily, Italy). Furthermore, the falling head test was conducted to assess the hydraulic conductivity (Ks) variation in the HSTW, in order to understand the influence on the CR biomethane production. Average methane content values were 130.57 Nm3CH4/tVS (±24.29), 212.70 Nm3CH4/tVS (±50.62) and 72.83 Nm3CH4/tVS (±23.19) in August, September, October 2022, respectively. Ks was correlated with both dry matter (R2 = 0.58) and fiber content (R2 = 0.74) and, consequently, affected the biomethane yield that increased at the Ks increases (R2 = 0.30 in August, R2 = 0.57 in September). In the framework of a circular economy, results showed the successfully possibility of integrating the bioenergy production into TWs. The research could contribute (i) to encourage plant operators to reuse biomass from TWs for local energy production and (ii) to help plant operators to understand Ks effects on the biomass biomethane yield, in order to increase the sustainability of the system and to reduce the maintenance costs.
Childhood Emotional Abuse, Neuroticism, Perfectionism and Workaholism in an Italian Sample of Young Workers
Authors: Verrastro Valeria , Cuzzocrea Francesca , Calaresi Danilo , Saladino Valeria
Published: February 2024

Childhood emotional abuse (CEA) has been linked to a range of unfavorable outcomes, including the development of unhealthy personality traits and maladaptive coping mechanisms and behaviors. In this study, our objective was to investigate whether neuroticism and perfectionism act as mediators in the relationship between CEA and workaholism, while also evaluating the gender invariance of the hypothesized model. A cohort of 1176 young workers, with a balanced gender representation (50% female), aged 18-25, participated in the study by completing self-report questionnaires. The results revealed significant connections between all direct and indirect links, indicating a complex interplay between childhood emotional abuse, neuroticism, perfectionism, and workaholism. Importantly, the mediation model exhibited no significant differences between genders, suggesting that the identified relationships are consistent across both male and female participants. This research underscores the critical importance of early identification of childhood emotional abuse and advocates for the implementation of trauma-informed care to address the negative consequences of emotional abuse, ultimately aiming to prevent the development of workaholism. Furthermore, the findings emphasize the necessity for tailored prevention strategies, focusing on mitigating neuroticism and perfectionism as potential pathways for effective therapeutic interventions.
Modeling Strategic Interventions to Increase Attendance at BCYF Community Centers
Authors: Moro-Araujo Alejandro , Alonso Pastor Luis , Larson Kent
Published: February 2024

Community centers play a crucial role in urban environments, providing physical and educational services to their surrounding communities, particularly for students. Among the many benefits for students are enhanced academic outcomes, improvement of behavioral problems, and increased school attendance. Such centers are also particularly vital for low-income and racial minority students as they are pivotal in giving them outside-of-school learning opportunities. However, determinants influencing attendance at community centers remain largely unexplored. Using census data, Boston Centers for Youth and Families (BCYF) attendance data, and specific center attributes, we develop human mobility gravitational models to predict attendance across the BCYF network. Using those models, we investigate the potential effects on general and student attendance by changing center attributes, such as facilities and operating hours. We also research the impact of changing the walking accessibility to those centers on their respective attendance patterns. After the analysis, we find that the most cost-effective policy to increase BCYF attendance is changing each center’s educational and recreational offerings far beyond any accessibility interventions. Our results provide insights into potential policy changes that could optimize the attendance and reach of BCYF Community Centers to underserved populations.
Climate Change and Architecture: The Link Overlooked
Authors: Majumder Rajarshi
Published: February 2024

Every year since the last fifty years, the world is waking up to higher and higher average temperature of the earth. Initially it was thought that this trend is a part of cyclical warming and cooling of the earth and nothing to be much worried about. However, with weather conditions become erratic and unusual over a large swath of the planet more and more frequently and regularly, scientists started to speak of Climate Change and people started to listen. In this paper we briefly discuss the link between global warming, climate change and current policies in the developing world to drive home the urgent need for alternative thinking. We briefly discuss the theoretical link between economic development and greenhouse gas emission and lay the micro foundation of the Environmental Kuznets Curve (EKC) before providing some evidence of global climate change and why this is a matter of concern for social scientists. Then we explore two avenues through which human activities are aggravating the situation especially in developing countries – the role of business architecture and the role of built architecture. We argue that these twin architecture are aggravating global warming by moving away from sustainable development policies.
MoNOT3/5 Subunit Is Important Roles in Infection-Related Development and Stress Responses in Magnaporthe oryzae
Authors: Kim Youngmin , Jo Miju , An Sunmin , Lee Yerim , Choi Eu Ddeum , Jeong Min-Hye , Kim Ki-Tae , Park Sook-Young
Published: February 2024

The multifunctional carbon-catabolite repression-negative on TATA box less complex (CCR4-NOT) is a multi-subunit complex present in all eukaryotes, including fungi. This complex plays an essential role in gene expression; however, a functional study of the CCR4-NOT complex in the rice blast fungus Magnaporthe oryzae has not been conducted. Seven genes encoding the putative CCR4-NOT complex were identified in the M. oryzae genome. Among these, a homologous gene, MoNOT3, was overexpressed during appressorium development in a previous study. Deletion of MoNOT3 in M. oryzae resulted in a significant reduction in hyphal growth, conidiation, abnormal septation in conidia, conidial germination, and appressorium formation compared to the wild-type. Transcriptional analyses suggested that the MoNOT3 gene affects conidiation and conidial morphology by regulating COS1 and COM1 in M. oryzae. Furthermore, monot3 exhibited a lack of pathogenicity, both with and without wounding, which is attributable to deficiencies in the development of invasive growth in planta. This result was also observed in onion epidermal cells, which are non-host plants. In addition, the MoNOT3 gene was involved in cell wall stress responses and heat shock. Taken together, these observations suggest that the MoNOT3 gene is required for fungal infection-related cell development and stress responses in M. oryzae.
Guidelines on Management of Hereditary Polyposis Syndromes in Pediatric Patients: Agreement, Disagreement and Where it Matters
Authors: Hudson Taina , Phen Claudia , Rojas Isabel , Cohen Shlomi , Hyer Warren , Attard Thomas
Published: February 2024

Hereditary polyposis syndromes are rare but potentially devastating conditions which require multidisciplinary care from an early age. Societal guidelines serve as the framework for disease diagnosis, surveillance and treatment. Guidelines are based on expert opinion and ideally are evidence-based; however, recommendations may vary among different societies and can result in discordant care. This paper aims to summarize key differences in management based on societal guidelines for pediatric polyposis syndromes and identify some of the factors which may contribute to divergence in care.
Nanostructured PR-Rich CexPr1-xO2-δ Mixed Oxides for Diesel Soot Combustion. Importance of Oxygen Lability.
Authors: Mekki Imene , Grzybek Gabriela , Kotarba Andrzej , García-García Avelina
Published: February 2024

Soot combustion experiments with 5%O2/He were conducted using model soot, and four distinct compositions of CexPr1-xO2-δ oxides were prepared, varying nominal cerium com-positions (x=0, 0.2, 0.3, and 1). The catalyst samples were comprehensively characterized using techniques such as XRD, Raman spectroscopy, HR-TEM, N2 adsorption at −196 °C, XPS, O2-TPD, H2-TPR, and work function measurements. The Pr-rich compositions, rang-ing from Ce0.3Pr0.7O2-δ to PrO2-δ, resulted in a significant increase in the total evolved O2 amounts and enhanced catalyst reducibility. However, a decrease in textural properties of the catalysts was noted, being particularly important for the pure praseodymia under the synthesis route conducted. The catalytic activity was investigated under two contact modes of mixing between soot and catalyst: loose and tight. The results revealed that the catalytic performance is associated with the surface contact in tight contact mode and with the combination of surface/subsurface/bulk oxygen mobility and the BET surface ar-ea in loose contact mode. Notably, the T10 and T50 parameters were achieved at much lower temperatures than the uncatalyzed soot combustion, even under loose contact conditions. Specifically, the 50% conversion was achieved at 511℃ and 538℃ for Ce0.3Pr0.7O2 and Ce0.2Pr0.8O2, respectively.
While no direct correlation between catalytic activity and work function was observed a significant relationship emerges between work function values and the formation of oxy-gen vacancies, whatever the conditions used for these measurements. On the other hand, the ability to generate a high population of oxygen vacancies at low temperatures, rather than the direct activation of gas-phase O2, influences the catalytic performance of Pr-doped ceria catalysts, highlighting the importance of surface/subsurface oxygen vacancy generation, which was the parameter which showed better correlation with the catalytic activity, whatever the soot conversion value or the mode of contact considered.
Investigating the Mechanism of Strong Roof Weighting and Support Resistance Near Main Withdrawal Roadway in Large-Height Mining Face
Authors: Du Junwu , Huang Qingxiang
Published: February 2024

Aiming at investigating the strong roof weighting when the large height mining face is nearing the main withdrawal roadway, the 52,304 working face (WF) nearly through the main withdrawal roadway mining in a colliery of Shendong coalfield was taken as the research background. The ground pressure, roof structure, and superposition effect of stress in the last mining stage were studied by field measurement, physical simulation, and numerical calculations. The obtained results demonstrated that the main roof formed the “long step voussoir beam” structure under the influence of the main withdrawal roadway. The superposition effect of the front abutment pressure of the WF and the concentrated stress of the main withdrawal roadway caused the stress asymmetrical distribution on the two sides -level hard rock straof the main withdrawal roadway, and the stability of the pillar on the mining side decreases. The initial average periodic weighting interval was 20.7 m. While the WF approaches the main withdrawal roadway, the pillar near the WF of the main withdrawal roadway collapsed, the main roof was broken ahead of the WF, and the actual roof control distance of support and the periodic weighting interval increased by 2.56 and 1.26 times the normal state, respectively. Consequently, the “static load” of the immediate roof and the “dynamic load” of the sliding unsteadiness of the long step voussoir beam increased. The structural model of the “long step voussoir beam” under the superposition of “static and dynamic load” was established concerning those results, and an expression was proposed to compute the support resistance. Meanwhile, the mechanism of strong roof weighting was revealed when the WF was nearly through the main withdrawal roadway. The research conclusion is expected to provide a guideline for the safe withdrawal of the large-height mining faces under similar conditions.
Compressive Fracture Behavior and Acoustic Emission Characteristics of Sandstone under Constant Crack Water Pressure
Authors: Huang Jiancheng , Luo Yong , Pu Chengzhi , Luo Song , Si Xuefeng
Published: February 2024

Engineering rock containing flaws or defects under a large water source is frequently subject to the couple influence of constant crack water pressure and geostress. To investigate the fracture behavior of precracked rock under hydromechanical coupling with constant crack water pressure, compression tests were conducted on red sandstone specimens containing a single crack of different angles using a device to realize the constant crack water pressure during loading, and the failure process of rock specimens was monitored by acoustic emission (AE) technique. The results show that the presence of constant crack water pressure has a significant promotion effect on the development of shear wing cracks, and the promotion effect is influenced by the prefabricated crack angle and water pressure. As the constant crack water pressure increases, the failure mode of the 0° precrack specimen changes from “X”- shear failure to the single oblique shear failure along the shear wing crack direction, the main failure crack of the inclined precracked specimens (precrack angles of 15°, 45°, and 60°) changes from a small acute angle with the prefabricated crack to a direction along the shear wing crack, and irregular cracks occur at the chipped prefabricated crack in the 90° precracked specimen. With an increase in the constant crack water pressure, the average energy for a single hit, cumulative AE energy, and cumulative AE hits decrease, and the proportion of the tensile cracks increases and that of the shear cracks decreases.
A Successful Alternative for Water Control and Reduction of Bypassed Pay in a Heavy Oil Reservoir: Case Study in Yuralpa Field, Ecuador
Authors: Hernandez Rubys M. , Teran Nayda G. , Rios A. F. , Bastidas D. V. , Vega J. A. , Mora H. E. , Martinez A. S.
Published: February 2024

Yuralpa field is characterized by a biodegraded heavy crude oil (from 14 to 18 °API) and a strong water drive that causes early water breakthrough in wells. Once the water breakthrough, the water cut increases rapidly to reach values between 90 and 95%. This effect occurs irregularly in the field and more prematurely in the wells located in the Chonta sector where the crude oil is the heaviest and most viscous. The excessive water production generates high handling costs and has caused the early abandonment of zones by applying cement squeeze and mechanical isolation (plugs) which generally required a rig intervention.

This paper summarizes a case study of the first application of water control in Yuralpa field using a Hydro Selective System (HSS) completion. It describes the relevant reservoir characteristics that lead to select this type of completion for Well YCCA-020 in a field where traditionally wells have been completed in a simple way. In addition, it explains the completion design, and it details the steps to change the position of the HSS valve and production results.

Well YCCA-020 was selected for this type of completion mainly because of the presence of a local vertical lithological barrier that separates the reservoir in two intervals. It is important to consider that the well was drilled in the higher viscosities sector of crude oil in the field that have more probability to leave bypassed reserves due to the difference in water-oil mobility ratio. The HSS valve was located between both intervals, and the well started producing from both intervals. Once the water cut reached 92% (105,000 bbl cumulative crude oil in 295 days), the valve was changed of position to produce from the upper interval, reducing the water cut up to 75% and increasing the oil rate to almost 200 BOPD. This completion allowed to drain the reserves of the lower interval (where the bottom aquifer is acting directly), reducing bypassed pay and to continue draining the reserves of the upper interval through a rigless intervention.

The water control completion probed in Well YCCA-20 was successful. This system could lead to future applications to water control in analogous reservoirs, simultaneously decreasing the risk of bypassed reserves in the field and reducing cost compared with workover or selective conventional completion used to isolate zones.
Multiphase Flow Pattern and Screen Selection: Two Overlooked Parameters Essential to Reservoir Control Valve Optimization
Authors: Malbrel C. A. , Kale R. , Agarwal J. , Gohari K.
Published: February 2024

The deployment of sophisticated Autonomous Inflow Control Valves (AICV) to manage reservoir uncertainty and water production in stand-alone completion is becoming increasingly popular, and the range of options available is constantly evolving. To date, much of the extensive testing performed with AICVs has assumed homogenous/dispersed flow (taking no direct account of production phase separation) and has ignored the potential role of varying screen geometries. Under a wide range of downhole conditions, stratified flow may be a more likely scenario and the full scale testing of AICV assembly under realistic downhole field conditions provides insights into the annular flow behavior and identifies critical interactions between the AICV and the screen, potentially leading to new means of enhancing AICV performance.

A series of multiphase flow tests was performed on full size screen and housing assemblies to verify flow pattern under realistic conditions and assess the potential for screen geometry to have an impact on the AICV performance in stratified flow conditions.

Various features of the screens, such as screen type (mesh screen, wire wrap), and screen/basepipe standoff height were investigated under various water fractions, flow rates and oil viscosities. The screen jacket was also partially blocked by a sleeve to simulate the partial burial of the screen in the wellbore. The multiphase flow patterns in the annular space around the screen and inside the valve housing were monitored through observation windows and high-speed camera, in conjunction with pressure drop across the screen and the entire assembly.

Under normal flowrates, it is observed that the multiphase flow shows a stratified flow pattern around the screen, with the location of the water/oil interface highly sensitive to the oil viscosity. For high viscosity oil (100cp), the W/O interface is very low, resulting in a high water phase velocity high. This provides another reason why the onset of water production in heavy oil is often causing rapid screen plugging and high drawdown. Under these conditions, stratified flow is also prevalent in the valve housing, irrespective of the screen type.

Under semi buried conditions, the screen type and standoff between the screen jacket and the basepipe played an outsize role in defining the flow pattern inside the housing. With a mesh screen and tall standoff, the flow pattern remains largely stratified while a wire wrap screen yields a bubbly/misty condition. As a result of these change in flow pattern, AICV performance is expected to be degraded when wire wrap screens are used in partially collapsed wellbore.
Deepwater Application of Proppant Controlled Release Inhibitor Leads to Successful Well Production in Gulf of Mexico
Authors: Spurr N. , Stanley D. , Usie M. , Debenedictis F. , Schneider D. , Lawler A.
Published: February 2024

Designing and achieving a deep-water frac pack in a new field that delivers low drawdown/low skin and high PI's is always a challenge. Successful design work, planning and execution are all key parameters. With additional challenges of a suspected high asphaltene content crude oil with relatively low onset pressures (AOP), another challenge was posed, "Can you place a solid inhibitor during the completion phase that can prolong expensive remediation treatments, while maximizing value by adjusting the chemical release pressure?" A new solid, controlled release proppant like inhibitor was introduced with a custom designed release pressure close to that of the AOP to solve the operator problem.

Frac packs were designed aggressively to achieve high net pressures, which historically achieve low drawdowns, low skin, and high PI's, and consequentially reduce the asphaltene deposition tendencies of the crude due to pressure drops. The controlled release asphaltene inhibitor proppant was tested for performance via asphaltene dispersion testing to ensure inhibitor performance and to obtain a minimum recommended loading. To further determine the best treatment for a new field development of two subsea tieback wells, reservoir conditions, AOP and desired protection points were evaluated.

The optimized fracturing design and custom controlled release asphaltene inhibitor proppant for the five treatment zones resulted in higher than expected PI's, lower than expected skins and overall exceptional wells. To date, no asphaltene deposition has been suspected and completion skin has remained low.

This paper introduces the next generation of flow assurance proppants that release asphaltene inhibitor when the well needs it the most and close to the AOP leading to less formation damage and a sustained production.
AI-Driven Well Log Interpretation Methodology for the Optimization of Water Control and Carbon Footprint Based on Polymer Injection
Authors: Katterbauer Klemens , Hassan Saleh , Al Shehri Abdallah , Yousef Ali
Published: February 2024

Energy-related sectors are making great efforts to guarantee the sustainability of their operations and lessen their carbon impact. Among these initiatives is field operation optimization to increase sustainability while preserving output levels. The oil and gas business is being greatly impacted by the fourth industrial revolution, which also makes it possible to analyze options for reducing carbon footprints more effectively. The formation can be precisely characterized, and its production behavior may be measured using modern production logging technologies. Technologies utilizing polymer injection have the ability to greatly reduce water cut, assisting in the reduction of carbon footprint. To model the effect of injecting polymers on the fluid production rates, we assessed the impact of several polymer injection techniques on the Volve field using a number of production and injection wells. The injection of polymers aids in lowering the reservoir's water production rates. This in turn lowers the carbon footprint associated with handling produced water and water injection. An important part of the optimization is the integration of well log interpreted polymer quantities to optimize the recovery. A probability-likelihood framework was used to calculate the overall carbon footprint after several scenarios were assessed to establish their widespread influence on carbon emissions. While the best injection technique may vary depending on a number of variables, polymers have shown to be capable of drastically lowering total carbon footprints while improving hydrocarbon output.
Wellbore Integrity Challenges in Saltwater Disposal: Case Study on the Fort Worth Basin
Authors: Khan Jawad Ali , Michael Andreas
Published: February 2024

This paper examines wellbore integrity in saltwater disposal (SWD) operations via modeling the stress-distribution evolutions within a well's casing-cement sheath-rock formation (C/CS/RF) system. Injection from SWD wells is thought to be responsible for elevated seismicity in regions of high oil-and-gas activity, such as the Fort Worth Basin in northeastern Texas. This modeling approach is useful for practitioners to take the appropriate preventative measures in the form of hazard-mitigation guidelines.

Induced (or "triggered") seismicity phenomena depend on the fluid-injection parameters, as well as the reservoir's petrophysical and geomechanical properties, including the presence of naturally-occurring pre-existing faults (PEFs) and their frictional behavior. The increase of the pore pressure within the FWB region, following water injection from SWD wells in 12 counties was obtained in the literature and used as inputs assessing the integrity of the C/CS/RF system against a total of ten modes of mechanical degradation. These degradation modes are induced by collapse/burst and compressive/tensile stress loads within the casing layer, inner or outer debonding, radial cracking, shear cracking, and disking within the CS layer, and tensile fracture initiation in the adjacent-RF.

The potential impacts of this wellbore-integrity compromise in SWD operations are discussed, as some of the aforementioned mechanical degradation modes are likely to adversely impact wellbore integrity a-priori to the occurrence of induced seismicity. Tendencies towards radial cracking and disking are identified to occur a-priori to any induced seismicity occurrences. This mechanical degradation means can facilitate for saltwater leakages towards neighboring zones in the subsurface and influence injectivity negatively.

Such saltwater leakages can have a stabilizing effect that may suppress induced seismicity. Three-dimensional (3D) hydromechanical modeling from past studies attempted to draw spatial and temporal correlations between seismic-activity observations and areas of pore-pressure elevation. Several localized regions of predicted-pore-pressure buildup did not indicate strong correlations with the recorded earthquake occurrences.
Non-Damaging Nano Polymeric Product Enhances Bridging Agents Packing for Limestone Reservoirs in the Persian Gulf
Authors: Pietrangeli G. , Hayden L. , Addagalla A.
Published: February 2024

Water-based drill-in fluids (WB DIF) with high concentrations of lubricants and other materials that assist in reducing the fluid loss are commonly used to drill tight and high overbalance reservoirs in the south-west Persian Gulf. Exposure and damage of the formation by these products is highly possible due to the characteristic high fluid loss of WB DIF. This paper discusses the improvement of a WB DIF by adding a non-damaging polymeric product to enhance filtercake packing. The chemistry and the particle size of the polymeric product enhances the bridging properties of the calcium carbonate, thus improving the wellbore strengthening and reducing formation damage.

Return permeability (RP) testing is widely used in the oil industry to evaluate fluid-rock interaction. RP testing indicates potential causes of production impediments generated after drilling by filtercake deposition and filtrate invasion. Limestone outcrops from Mississippian formation with a permeability between 9-16 md and 14-18% porosity were used for the RP tests. Damage minimization from the drill-in mud with no requirement for a breaker were the main goals for the fluid development to drill the tight limestone reservoir. Therefore, higher RP values to permeable oil was the desired outcome of the tests.

The solid particles used in the drill-in fluid should generate optimal packing to achieve lower filtrate invasion. Software simulation and calculations for bridging optimization are highly recommended, but brittle particles such as calcium carbonate could deviate from the predictions after passing though the drilling nozzles and changing their size with no control. The use of non-damaging polymeric and deformable particles could help with the packing of the bridging agents and improve the wellbore strengthening by reducing filtrate invasion. This paper presents results for a fluid before and after the addition of bridging enhancer. In the study, the addition of the non-damaging polymeric material had no effect on the rheological properties of the fluid. Furthermore, the fluid loss decreased almost 40% at 160°F and 85% at 250°F using paper as a filtration media. The RP of the original WB DIF was 79.7% at 4 cm3/min using LVT-200 as a permeating oil and 89% after centrifugation, indicating connate water damage. The RP of the enhanced fluid was 92.7% at 4.0 cm3/min and 93.5% after centrifugation, indicating no damage by connate water and a significant decline in the formation damage by filtrate invasion due to the improved packing of the bridging agents. No breaker was required for the fluid due to the high RP thus decreasing cost of the operation by reducing rig time and chemical treatments.

Return permeability evaluation between the drill-in fluid and reservoir rock is essential for oil producer wells to determine damage caused by the fluid, filter cake, and filtrate. Improving the packing of the bridging agents enhances fluid loss and decreases formation damage.
Formation Damage in CO2 Storage Wells – The Same, But Different
Authors: Byrne M. , Gilbert R. , Anderson R.
Published: February 2024

In many respects formation damage challenges in CO2 storage wells are similar to those in conventional oil and gas production wells and water and gas injection wells. But there are some differences from "conventional" well formation damage challenges. This paper outlines some issues specific to CO2 injection wells and proposes changes in focus prior to and during drilling and completion of these wells.

CCS (Carbon Capture and Storage) store can generally be split in to two categories – saline aquifers and depleted hydrocarbon reservoirs. Wells drilled and/or completed in these stores share some well injectivity challenges with conventional wells but also have some challenges specific to the store properties. In conventional injection wells it is generally accepted that well clean-up or back production prior to injection is beneficial as formation damage necessarily induced during well drilling and clean-up may be partially or fully removed. For saline aquifers and depleted hydrocarbon stores, well clean-up is normally not possible or practical. Direct injection after well completion is often required.

A new workflow capturing the key steps required to assure optimum well injectivity over the well life cycle has been developed and will be outlined in the paper. This includes but is not limited to: detailed analysis of CO2 phase behaviour in and beyond the lower completion; lower completion selection criteria specific to CO2 stores; laboratory testing and modelling focussed on CO2 store formation damage challenges; direct injection challenges and successful mitigations; ice scale and hydrate challenges in CO2 storage wells.

With increasing focus on CO2 storage globally, the workflow outlined presents an integrated approach to formation damage challenges. It demonstrates that although many of the challenges are similar to those in conventional wells, there are also some that are different and unique – the same, but different!
Analyzing Gas Well Productivity Change with Production in Unconsolidated Sandstone Using Rate Transient Analysis
Authors: Kumar Anand , Marandi Pratik , Verma Deepak
Published: February 2024

The primary objective of this paper is to demonstrate the changing productivity of the cased hole gravel packed gas wells due to wellbore matrix disturbance, rapid bean up operations and how daily production data (rates and flowing pressures/ temperature) can be used to analyse gas well performance along with estimation of Gas In Place. This work includes the identification of well problems and productivity changes, attributed to wellbore matrix disturbance or sub-surface issues in unconsolidated sands.

The analysis method used in this work is Rate Transient Analysis along with Pressure Transient Analysis. Bottom hole temperature behavior and Decline Curve analysis are also analyzed to validate the results captured from RTA. RTA is ideal for establishing a well's productive capability early in its life (after 3-6 months) and categorizing subsequent well decline behavior as either reservoir depletion or productivity loss through time (or a combination of the two). Through interpretation of diagnostic plots, such as the Flowing Material Balance Analysis and Type Curve Analysis plots, specific productivity issues can be easily identified and classified using simple pattern recognition.

Field examples from multiple gas wells across KG Offshore Deep Water (Water depth > 400m), completed with cased hole gravel pack, are included in our study. The present case study indicate the apt use of RTA, PTA and other bottom hole parameters to determine current K, changing skin & the most important GIIP of single well gas fields. RTA will supplement and to some extent give the actual estimation with less error. Deliverability issues such as wellbore matrix disturbance and gravel pack degradation associated with unconsolidated sands are identified. The issues has been validated by flowing temperature behavior. Results show how RTA can be used as a practical screening tool, identifying underperforming wells and quantifying the potential benefits of remedial action based on remaining reserves.

This paper presents a novel application for RTA - as a screening tool for diagnosing underperforming wells and estimating their optimum producing rates. The industry tends to undervalue the potential benefit of all but the simplest remedial measures for underperforming producing wells for two reasons- 1. Poor performance is often simply accepted as a statistical reality and 2- operators do not even realize that their wells are underperforming. In case of deep water, work over job or drilling new well is a very costly affair. Also, time plays a major role in economics of a development project. If the issue(s) can be resolved, production improvements aggregated field-wide could have tremendous economic implications.
Technology Optimization and Field Test for Improving Development Effect of Deep Low-Permeability Water-Sensitive Reservoirs
Authors: Yang L. L. , Long H. , YUAN A. W. , LUAN R. Z. , Yang X. , Liu P. H. , Ren Y. L. , Wu X. M.
Published: February 2024

The main focus is on exploring the optimal gas injection development model for deep, low permeability and water sensitive reservoirs. The technical limit of liquid CO2 injection was defined, which would effectively guide injection parameter design. A new type of anti-corrosion and gas-tight injection string were designed, which would assure safe and efficient injection. The successful field test provided an effective energy replenishment method for deep, low permeability and water sensitive reservoirs, and also provided technical reference for the effective utilization of other similar reservoirs in the next step.
Engineering for Success: Design and Execution of Fluids for Optimum Injectivity - A Case Study
Authors: Storli Christer , Asko Arne , Twynam Allan , Hovem Knut , Knox Dave , Thibodeaux Brittany Granger , Cascone Alessandro , Kamel Abdalla
Published: February 2024

Two North Sea water injector wells have achieved high matrix injectivity rates without backflow to clean-up prior to commencing injection. Achieving successful results on direct water injection wells is recognised as a technical challenge, requiring detailed design and validation work around the selection and execution of the drilling and completion fluids. Engineered water-based reservoir drilling fluid and post-drilling chemical "breaker" treatments were utilised for these open hole screen completions.

The technology around the use of breaker fluid has evolved in recent years, yet successful application is challenging when two objectives are combined; achieving the required injection rate without clean-up flow prior to injection and keeping the injection pressure below the minimum fracture gradient for uniform matrix injection over the full length of the completed interval.

Once suitable fluid formulations have been identified and validated by laboratory testing, detailed engineering procedures are required to ensure that the fluids are maintained within tight design specifications through the execution phase. For example, one critical key to success is ensuring that formation solids and residues incorporated into the drilling fluid are minimised to reduce the risk of plugging the matrix permeability. Once the well is drilled, ensuring that the breaker fluid is placed across the entire zone of interest and the filter cake is removed in a controlled and uniform manner facilitates good injectivity results.

This paper describes; the technical challenges presented by this project, the extensive laboratory testing performed as part of front-end engineering and design, an overview of the field execution across the two water injector wells, the results and the lessons learned.
Iron Sulphide (FeS) Scale Prediction-Modelling Development and Experimental Methodology Design
Authors: Jarrahian K. , Sorbie K. S. , Azuddin F. J. , Ness G.
Published: February 2024

Iron sulphide (Fes) scale is widely present in both oilfield and geothermal systems and causes a range of production and Health and Safety problems. Although substantial progress has been made, continued efforts are needed to precisely understand and predict FeS scaling. The aim of this work is to present a simple robust model for FeS scale experiments in the laboratory. This model predicts saturation ratios (SRs) and masses of the formed iron sulphide scale, final solution compositions and final pH levels, for specific lab experiments. This model is verified by comparing results with carefully designed experiments which are monitored by a range of analytical experimental techniques, e.g., ICP-OES, ESEM/EDX and XRD (explained in the text). These analytical methods allow us to analyse for all the components present, such as initial and final [Fe2+], aqueous [H2S] levels etc, and they also give direct information on the morphology of any precipitates formed, either as crystalline or amorphous solids.

Experiments were performed in an anaerobic chamber since we were using iron (II) ions (Fe2+) from both iron (II) chloride tetrahydrate and also ammonium iron (II) sulphate hexahydrate. The latter, known as Mohr salt, is thought to be a more reliable source of Fe2+. In fact, we found different crystallographic types of FeS scale precipitate from each of these 2 irons (II) salts.

In addition, we observed that when FeS particles are precipitated from the solution, then under some circumstances some FeS particles can remain in colloidal suspension. This has implications for the level of measured "[Fe2+]" by ICP which measures the total Fe in solution, i.e., the free Fe2+ ions as well as any suspended colloidal FeS. The results show that there is a quantitative agreement between the experimental results and the predictions of the model in determining final pH of solution, final [Fe2+] and mass of FeS precipitate. However, it was also noted in some cases where discrepancies occurred – e.g., in [Fe2+] level – this may be ascribed to the colloidal nature of FeS scale.

The information presented in this study will help production chemists to understand the chemical formation of FeS in laboratory testing, and this will assist in the selection and design for future scale inhibitor treatments.
Mechanistic Modeling of Wellbore Integrity During CO2 Injection in Deep Saline Aquifers
Authors: Ali Khan Jawad , Michael Andreas
Published: February 2024

In this paper, we examine wellbore integrity during carbon dioxide (CO2) injection in deep saline aquifers, by modeling stress-distribution evolutions within the casing-cement sheath-rock formation (C/CS/RF) system. For our analysis, a mechanistic model is used, which considers a total of eleven ("10 + 1") modes of mechanical degradation assessing each of the three layers of the C/CS/RF system discretely.

The integrity of the wellbore is assessed by modeling the casing layer as a thick-walled cylinder and the adjacent-RF layer as a poroelastic solid, accounting for fluid infiltration into and out of the pores in close proximity to the CS layer. The magnitude of the normal-effective stresses at the C/CS and CS/RF interfaces provide calibration parameters for the stress distributions within the intermediate-CS layer, honoring linear elasticity. This novel method is used to determine the initial state of stress within the C/CS/RF system with balanced conditions inside the wellbore, following cement setting. Using input data from the literature, the integrity of the C/CS/RF system is assessed over a 30-year period of bulk-CO2 injection in a closed (bounded) system and an open (unbounded) system subsurface aquifer.

In closed-aquifer configurations, disking failures along with radial and shear cracking tendencies are indicated within the CS layer, providing potential pathways for CO2 leakages back into the atmosphere. In open-aquifer configurations, the three aforementioned tendencies for mechanical degradation remain, albeit at a smaller degree. The generated stress distributions demonstrate no indication of inner debonding along the C/CS interface, while the outer-debonding limit is approached on the CS/RF interface, but never exceeded. Moreover, no tensile failures (via longitudinal or transverse-fracture initiation) is expected along the CS/RF interface, nor casing failures (related to compressive/tensile loads, collapse and burst stress loads). Finally, none of the scenarios considered are expected to generate seismic activity along preexisting faults (PEFs) near the injection well.