bluuebunny/crossref_metadata_2025_split huggingface dataset:
Petrophysical Characterization of the Qusaiba Formation, Tabuk Basin, North West Saudi Arabia: Implications for Reservoir Dynamics in a Shale Play
Authors: Amao Abiodun Matthew , Alquraishi Abdulrahman , Alghamdi Faisal , Aref Lashin , Elshreef Khaled , Laboun Abdulaziz 
Published: February 2022

Abstract
The Qusaiba formation is an emerging unconventional play in Saudi Arabia. A detailed study was conducted on acquired representative samples which covered all the units of the Qusaiba formation from three locations in North Western Saudi Arabia. This study was conducted to fully characterized the formation to understand the governing petrophysical factors, their variability in the basin and implications for reservoir fluid dynamics in this unconventional reservoir.
This is a field to laboratory study. A field trip was conducted to the location to collect representative samples at three locations in the Tabuk basin. The formation outcrops were sampled at intervals of about one meter, to ensure a detailed coverage of the sampled Qusaiba formation. The samples were then subjected to detailed mineralogical analysis comprising of XRD, SEM and petrophysical characterization to determine the porosity, permeability, pore size distribution and capillary pressure profile of the sampled formation. Detailed elemental and mineralogical analysis was necessary to understand paleo-depositional environments and infer any diagenesis in the samples.
Results show that the Qusaiba formation is divided into five main units. The basal Unit 1 overlies the Sarah sandstone, it is mainly thinly laminated dark grey shales, with some dark brown, grading into clayey siltstone at the top. Unit 2 is a mix of shales, siltstone and sandstone, Unit 3 is composed of thinly laminated dark-gray black shales, Unit 4 is composed of thinly laminated gray-green shales, with some mixture of siltstone. Unit 5 is a mixture of thinly laminated gray-green shale in the lower parts, thinly laminated gray-beige silty claystone and laminated beige-brown siltstone at the topmost part. Four lithofacies were identified, these are shale, claystone, siltstone and sandstones. The average porosity, permeability and pore radii in the sandstone facies was 14.13%, 8.3 md and 0.1323 microns respectively; in the siltstone it was 14.85%, 7.12 md and 0.1047 microns, in the claystone, it was 9.8%, 11.40 md and 0.029 micros, while in the shale facies it was 18.31%, 8.21 md and 0.0167 microns. It was observed from the pore size distribution plot that the shale samples exhibit fractures sized pore radii in the macro-pore range. These data demonstrate the high heterogeneities present within the Qusaiba formation, especially in the interbedded layers.
The results from this study provide an understanding of the pore structures in the Qusaiba formation and the main lithostratigraphic facies governing reservoir fluid flow. The pore structures of the main Qusaiba lithofacies were characterized extensively, this would enhance the understanding of how to unlock the potentials of this unconventional reservoir. It shows that fractures in the fractured shale units could have high impact on fluid flow.
Collaborative Web Based Platform for 3D Reservoir Characterization and Geosteering Planning on the Cloud
Authors: Santoso Gagok-Imam , Denichou Jean-Michel , Al-Alqum Wael , Zeidan Motaz , Satti Mohammed 
Published: February 2022

Abstract
New developments in Machine Learning and Artificial Intelligence-based interpretations are bringing a step change in the integration of multi-physic evaluations and management of reservoirs in real time. But it also requires game-changing digital developments to deliver the larger computing power required and to facilitate their access to multi-disciplinary (and sometime not co-located) team of experts and decision makers. This communication is sharing our experience of a web-based collaborative platform integrating operator's application used to produce realistic geological models and a service company's advance multi-dimension modeling and inversion supporting latest Logging While Drilling formation evaluation workflows. The system is now routinely used in case studies, allowing users to perform pre-job well placement feasibility analysis and post-job model refinement.
The technology behind is a modular Web platform that hides all the complexity of the modeling and inversions algorithms. Users can;
Upload their data to the application's virtual file system. Visualize 2D and 3D models, Launch modeling jobs for Ultra-Deep Azimuthal Resistivity (UDAR) and conventional formation evaluation measurements and finally monitor the inverted images unfold as the job progresses, all in the web browser.
The system enables multiple users to view and edit the shared models and observe and control the same job in a collaborative way. The simulation codes are run on the remote clusters or on the cloud. We will present the application of platform and models for 3D characterization in Norwegian continental shelf wells. The examples illustrate mapping of 2D and 3D structural complexity and how the system is used to update reservoir geomodels.
The platform is also used to identify optimal well position; define geosteering strategies in the pre-job planning phase, as well as to evaluate sensitivities, depth of investigation in specific scenarios and to analyze how the structural model uncertainties may be affecting the interpretation. Modeling and inversion are used to assess how structural complexities, lithological changes, oil-water contacts and saturation could be encounter in simulating future production. It is a key for quantitative robust interpretation and geomodels update. The platform allows fast deployment of latest research modeling and inversion prototypes. We finally present the latest results of full 3D modeling and various flavors of 2D imaging inversion results from multiple wells, visualized in the browser using a 3D viewer. The new digital solution improves understanding of 3D reservoir structure and fluid distribution around the wellbore.
Can We Predict Primary Creep and Least Principal Stress Shmin at Depth Either from Specific Surface Area or Weak Phase of Gas Shales?
Authors: Mandal Partha Pratim , Sarout Joel , Rezaee Reza , Hossain Mofazzal 
Published: February 2022

AbstractRecently short-term laboratory primary creep i.e., time-dependent deformation under triaxial in situ stress condition of ultra-low permeable gas shales have been utilized to work out geomechanical impacts of field development cycle such as modification of in situ stress state, prediction of production induced deformation, and understanding of fracture closure mechanism. However, obtaining creep data from the laboratory method is tedious, time-consuming, and costly. A simple power law model as a function of time involving instantaneous elastic compliance of the studied material B, and time dependent component n is used to describe creep and stress relaxation owing to the superposition principle of linear viscoelastic materials. Gas shales usually have a large specific surface area (SSA) because of the dominance of clay minerals (Illite, Smectite, Kaolinite, and Chlorite) and/or total organic carbon (TOC). Low-pressure nitrogen gas adsorption is a quick and cost-effective method to derive specific surface area value SN2 on powdered gas shale samples. From the observed strong empirical correlation between creep parameters and SN2value as well as with weak phase fraction ClayTocPHI (combination of clay, porosity, and TOC), a novel indirect approach is proposed to predict primary creep constitutive parameters either from the specific surface area (SSA) value SN2 or weak phase fraction ClayTocPHI of multiple gas shales at deeper subsurface formations (Figure 1). These gas shales cover a broad range of mineralogy, maturity, porosity, and depositional history. Through a case study, empirically derived creep parameters from SN2 are utilized to predict the least principal stress Shmin magnitude at depth of a six lithological layered gas shale formation with a viscoelastic stress relaxation approach. Direct field measurement validated the layered variation of the predicted Shmin magnitude.
The Potential for Underground CO2 Disposal Near Riyadh
Authors: Corrales Miguel , Mantilla Salas Sofia , Tasianas Alexandros , Hoteit Hussein , Afifi Abdulkader 
Published: February 2022

Abstract
Carbon Capture Storage (CCS) and Carbon Capture Utilization and Storage (CCUS) have recently gained global attention as promising techniques to mitigate net CO2 emissions. Within this framework, the Saudi Arabian 2030 vision targets the large-scale deployment of CCS and CCUS projects to promote its circular carbon economy. This study evaluates the potential for underground sequestration of CO2 emitted from industrial sources near Riyadh, Saudi Arabia, which emit 46 Mton/year.
A deterministic geologic model corresponding to the Unayzah Formation was constructed using published data incorporating sedimentary facies distribution, porosity, permeability, and connectivity. Compositional simulations were performed to assess the CO2 plume flow in the presence of conduits, barriers, and baffles. Similarly, injectivity and injection rate effects on solubility and residual trapping were evaluated. A sensitivity analysis and an uncertainty quantification study were carried out to obtain a probabilistic assessment of the total storage capacity and trapping contributions.
The geological evaluation indicates that the area under Riyadh is unsuitable because the Triassic sandstones are too shallow, and the Paleozoic section was entirely removed by erosion during the Carboniferous. Alternatively, the Hawtah area, at 150 km south of Riyadh, is deemed suitable for CO2 sequestration. These sandstones are porous, permeable, tightly sealed, and correspond to hydrocarbon reservoirs in anticlinal structures along the Hawtah, Nuayyim, and Dilam trends. They are favorable for CO2 disposal outside oil and gas fields due to lateral and vertical permeability barriers and up-dip pinch-out against the Batin arch. Simulation results, fifty years after CO2 injection and two hundred fifty years of monitoring, show that the Unayzah Formation satisfies the conditions of capacity, injectivity, and seal efficiency required for technical feasibility.
Furthermore, lower injection rates promote higher solubility and residual trapping due to gravity-controlled flow exceeding viscous and capillary forces. Residual trapping contributes ~ 50% to the storage, while solubility adds 10%. The variables that have a higher impact on secure trapping are residual gas saturation, water salinity, and permeability. The current CO2 storage capacity in the area evaluated exceeds 300 Megatons (Mt), and the assessment is still ongoing, with no vertical leakage through the caprocks of the Khuff and Sudair Formations.
Overall, the novelty in this research focuses on the unprecedented use of public domain data to construct a detailed geological model of the Unayzah Formation in the Hawtah and Nuayyim area that allowed a better understanding of CO2 flow mechanisms in the reservoir and its capacity to store CO2. This study concludes that the Unayzah reservoir in the Kharj-Hawtah area is a viable candidate for secure CO2 disposal from industrial sources in Riyadh.
An Organic Gel System for Water Production Issues Post Hydraulic Fracturing
Authors: Abdelwahab Omar , Almubarak Tariq , Schechter David , Bhatia Mukul 
Published: February 2022

Abstract
Water production post hydraulic fracturing is an issue that has been facing E&P operators worldwide for a long time. The water quantities produced can be significant with great amount of impurities. This not only reduces the oil production in those wells, but can also cause problems such as sand production, scale, corrosion and erosion. Moreover, it costs the E&P operators a lot of money every year to treat and dispose these produced waters. Crosslinked gels have been used successfully in the oil and gas industry to shut-off water producing zones. This study presents an experimental investigation of a polyacrylamide-based polymer and polyethyleneimine (PEI) system for water shut-off treatments.
The polyacrylamide-based polymer has a molecular weight of 40,000 Daltons. PEI crosslinker was obtained in a 50:50 aqueous solution with a molecular weight of 60,000 Daltons. The HP/HT rheometer was used to conduct the viscosity measurements. All experiments were done at a pressure of 400 psi. The shear rate was fixed at 100 s−1 and the temperature was ranged from room temperature to 350℉. The gelation time and the system's viscosity were both studied as a function of polymer concentration and salt concentration in the mixing water. Additionally, the effect of increasing temperature on the gelation time was examined. Moreover, an HP/HT aging cell was used to generate the gel that was used later for compatibility testing with a treated formation water from the Wolfcamp.
Increasing the polymer concentration was found to decrease the gelation time and increase the system's viscosity up to a specific limit. Moreover, we observed an increase in the gelation time as the concentration of NaCl was raised in the mixing water, however the system's viscosity decreased. Also, we noticed a decrease in the gelation time as the temperature increased. Finally, no incompatibility issues were observed between the polyacrylamide-based polymer/PEI system and the treated formation water.
Polymer-crosslinker systems should be stable and highly viscous to ensure an effective water shut-off operation. This work experimentally investigates the performance of a cheap polyacrylamide-based polymer and PEI organic gel system. The paper shows that the tested system is capable of sealing water production zones and can provide a promising alternative to current water shut-off systems used in the field.
The Contribution of Remote Factory Acceptance Test Towards Project's Schedule, Cost & Quality at Hawiyah Unayzah Gas Reservoir Storage
Authors: Al-Saidi Mansour , Al-Fouzan Hamad 
Published: February 2022

Abstract
This paper shares the Project Management Team's experience of conducting a Remote Factory Acceptance Test (Remote-FAT) at the Hawiyah Unayzah Gas Reservoir Storage project instead of the conventional approach of a conventional Factory Acceptance Test (FAT). The paper also highlights the advantages gained from a Remote-FAT, along with the value engineering created. In addition, this paper will present some deficiencies and areas of improvement. This shared experience is from the point of view as a PMT client or customer. At Hawiyah Unayzah Gas Reservoir Storage (HUGRS), the Remote-FAT approach was used with many disciplines, such as mechanical, electrical, pipelines, etc. This paper focuses on the process control system experience only, from 2020 to 2021. Meanwhile the HUGRS project is in progress and is expected to be completed by 2024.
Conducting a FAT is one of the main milestones in projects. The conventional method is usually to have individuals physically visit the manufacturer to check and approve shipping the purchased devices/equipment to the project site. Sometimes this practice "FAT" takes place in the same country where the project is being constructed. But in other cases, the manufacturer is not even on the same continent, requiring travel of hundreds or thousands of kilometers. During COVID-19, there were many active projects that needed to conduct FAT activities, but travel was suddenly restricted. Therefore, the only option was to proceed with Remote-FAT. One of these running projects is HUGRS.
The Remote-FAT is a virtual inspection check conducted by the client and vendor via online video streaming at the manufacturer location. Multiple cameras are used and located in different views to visualize whatever needs to be seen. In some cases, the Remote-FAT can be conducted through sharing a screen only, such as system graphics and logic test. The client and the vendor verify and conduct the test, following the same steps that they would perform in the conventional FAT. This Remote-FAT had already existed for a couple of years, but many project managers considered it as a fancy tool that did not add value. This evaluation was proven wrong by COVID-19. Remote-FAT has become the most convenient approach recently and adopted around the world. For the past two years, the process control systems engineers at HUGRS conducted many Remote-FATs with different vendors for dissimilar systems. The advantages and disadvantages were recorded as lessons learned — part of PMT practice — and will be shared in the next sections of this paper.
Sensor-Ball: Field Deployment of Autonomous and Untethered Surveillance
Authors: Larbi Zeghlache Mohamed , Bukhamseen Ahmed , Muailu Husain , Abdulghani Ahmed 
Published: February 2022

Abstract
With the evolving sensor technologies and advances in integrated solutions, routine surveys and interventions in oil and gas fields are going through a major revamp. The most recent developments in autonomous and untethered devices set a new paradigm shift in such crucial and frequent well operations. In this paper, field implementation and deployment of the novel Sensor-Ball technology is discussed to highlight success, challenges and lessons learned.
Sensor-Ball is a small device, almost a tennis-ball size that enables autonomous and untethered logging of pressure, temperature, and tri-axial magnetic field amplitude. This intelligent device is self-powered using a battery pack with a battery life that suffices logging a dozen wells in a raw including logging time and data transfer time. The internal memory is designed for large and high definition data rates for high resolution and extended recording. Sensor-Ball is encapsulated in a ruggedized housing that can withstand downhole conditions as the device travels on a free-fall down to the programmed depth, as well as while floating back to the surface. This housing is light enough to enable efficient and flawless return of the Sensor-Ball exclusively under bouncy effect once the attached weight is dropped off.
For the deployment of this innovative technology, new procedures and guidelines are developed to ensure successful journey of the Sensor-Ball. Despite the failsafe features, prejob plan, and risk assessment procedures complement this user-friendly technology and make it reliable, efficient, and easy to use.
The results of the field trial of Sensor-Ball in water supply wells revealed a superior data quality of both log-down and log-up. In fact, during the mission time of three hours only, thousands of feet of high-resolution data were collected. This operation would have taken double the time and a much more wellsite footprint, in addition to increased HSE risk, if a standard wireline/slickline unit was mobilized for this routine operation. Sensor-Ball is a reliable and more advanced alternative to traditional well surveillance methods considering the operational efficiency and comparison with benchmark data. In fact, the footprint, cost and time savings are substantial, especially in an offshore environment where barges are mobilized and operations depend on weather conditions.
This technology is a major breakthrough in the surveillance and logging world as it enables a fully autonomous and untethered acquisition of high-resolution data. Sensor-Ball offered more with less and will ultimately replace traditional surveillance and intervention methods.
Supercritical CO2 Recirculation in Reservoirs for Continuous Storage and Production of Renewable Energy
Authors: Aljughaiman Ibraheem 
Published: February 2022

Abstract
Over the past decades, many countries have started to place emphasis towards electricity production from renewable sources, such as solar and wind, to limit the amount of CO2 emissions in the atmosphere and reduce global warming. However, solar and wind energy are exclusively reliant on climate conditions; thus, secure and continuous power supply cannot be guaranteed. Therefore, maintaining reliable and continuous power supply calls for concepts and implementation of energy storage techniques. CO2 subsurface energy storage is one of the most innovative techniques that could be applied to solve drawbacks of traditional storage techniques such as scale limitation in both capacity and time, low efficiencies, environmental concerns, or high costs.
In this paper, we reviewed and assessed the use of CO2 subsurface energy storage systems by looking at the thermodynamic cycles, machinery, and reservoir conditions. Moreover, a comprehensive study on multiphase flow in porous media has been conducted by looking at capillarity, relative permeability, mass balance, heat balance, thermal properties, and phase behavior. Different well configurations have been compared by performing injection and production simulations to conclude that the use of horizontal injection and production wells is preferred over other proposed well configurations for many reasons such as decreasing the amount of initial CO2 needed to develop and operate the reservoir, covering a large area of the reservoir, and increasing the system's capacity and efficiency.
The findings show that CO2 subsurface energy storage system can operate if certain requirements exist: 1) availability of initial CO2 supply, 2) availability of the necessary equipment and solar, or wind, power plants, 3) safety of the targeted location, 4) two deep, clean reservoirs with high porosity and high permeability and 5) presence of a caprock. Ensuring the existence of requirements determined from this study will allow a safe, large (in terms of capacity and time), efficient, and cheap method to store and produce renewable energy continuously.
In the foreseeable future, the world will inevitably depend on electricity production from renewable sources; therefore, more energy storage techniques have to be developed. CO2 subsurface energy storage systems have to be considered as they can contribute to reducing emissions and global warming, ensuring a secure and continuous power supply, and solving the drawbacks of traditional storage techniques. The outcomes of this paper will contribute to the growth and development of CO2 subsurface energy storage systems