bluuebunny/crossref_metadata_2025 huggingface dataset:
Tracing the Origin of Annulus B Oil Return Using Integrated Geochemical Analysis to Identify the Effective Barrier Remediation Strategies, Case Study in Giant Gas Condensate Field
Authors: Alsaeedi A. , Gadelhak A. , Koksalan T. , Mubarak Albadi M. , Yassein D. , AlSaadi N. , Yan J.
Published: October 2023

One of the key aspects of sustainable production is to maintain the health of the reservoirs. The objective of this Paper is to demonstrate the establishment of best practices of geochemistry and its direct impact on well integrity by performing a reservoir to annulus oil correlation using geochemical methods in an onshore setting to establish the source of oil in the annulus. This application will significantly assist in assets sustainable production, future failure predictions and preventions.

Upon frequent observation of abnormal oil return from Annulus B of five gas wells, the herein approach was to identify the source of oil through specific geochemical analysis that consists of an analytical and interpretive protocol that defined to address the issue in an optimal and prompt manner using CSIA and Biomarker data. Simultaneously, an exercise to screen the wells integrity within one km radius was conducted to ensure that this unique challenge will not affect the nearby wells.

It was the 5th well with unexpected oil return from annulus B, Integrity Alarm was raised,it was not an isolated case,collected oil samples looked differently compared to produced oil for the same field,

Immediately, a compositional analysis was proposed but the uncertainty would have been high and the compositional similarity between reservoirs would have made the results inconclusive. Therefore, it was decided to perform Biomarker and Carbon Specific Isotope Analysis (CSIA) analysis.

Afterwards, the challenges were addressed and mitigated since this was a unique study conducted in such that: Availability of analysis within the existing PVT contractSecuring BudgetReceiving management approvalCollecting samples from reference oil reservoir for comparison

This study presents an application of geochemical analytical and interpretive protocols that includes CSIA and biomarker compositions of saturate and aromatic fractions of producing and annulus-B oils. By the end of the study the source of the oil return was identified, and a certain course of actions were listed. Then, remedial mitigation plan was put on place. Furthermore, six months of continuous monitoring targeting the nearby well's integrity took place where the suspected wells were treated with a comprehensive action on curing the well integrity challenges across assets.

Aging wells are a worldwide challenge and maintaining the wells flowing in healthy condition for as long as possible to reach or to exceed the wells expected life is what any organization is aiming for. This study has a significant outcome that can be scaled to the other wells and/or fields that encounter similar integrity issues. This implementation costs you a PVT sample but its game changer in the possible source of oil.
ESG. A Challenge for the Oil & Gas Industry?
Authors: Arboleda J. M.
Published: October 2023

The oil and gas industry has been constantly facing investment problems since 2014. The effects of the pandemic, combined with the geopolitical crisis in Europe, have offset the efforts made by OPEC and its allies to bring investment back to the market. Oil and gas suppliers have yet to find the formula to recall investments from financial institutions and other capitalists unwilling to increase capital. Price volatility, uncertainty about the oil demand outlook, and climate concerns prevent investors from acting.

For those reasons, many investing decision-makers are starting to demand fossil fuel companies for sustainability and/or ESG agendas, even if those agendas are not the most profitable option. Implementing ESG strategies in the oil & gas industry is no longer a voluntary option. It has become an obligation, especially if the company seeks international capital. But the implementation of ESG agendas in the oil & gas industry has arrived with several challenges. The lack of clarity and standardization to estimate the performance of ESG has cost trillions to the fossil fuel industry, bringing questions about the necessity of implementing ESG strategies and the benefits of their results.

This paper walks us through the challenges the oil & gas industry faces while implementing ESG agendas, highlighting the differences between International Oil Companies (IOCs) and National Oil Companies (NOCs). Private and hybrid oil companies have shown themselves to be more successful in implementing ESG, as their business model provides more flexibility in implementing business agendas and because IOCs are more susceptible to public pressure. NOCs play under different priorities and rigid structures that do not allow them to jump into activities other than those initially planned for the company.
Achieving Greenhouse Gas Management Success: How we Exceeded Our Target 8 Years Ahead of Schedule
Authors: Sricharoen P. , Dhanasin P. , Lertwiriyaprapa K.
Published: October 2023

This paper presents a case study of a leading national exploration and production company in Thailand, focusing on its pathways to decarbonization and long-term greenhouse gas emissions management. The company recognizes the importance of transitioning to a low-carbon economy and has set ambitious targets for reducing Greenhouse Gas (GHG) emissions intensity. The journey began since 2013, the company has been committed to lowering its emissions through various projects implemented in both domestic and international assets. By seamlessly integrating sustainability into its framework and strategy, the company addresses the challenges associated with GHG emissions effectively. Specific targets for reducing emissions intensity, primarily focusing on Scope 1 and Scope 2 emissions within its E&P operations have been set. The company has implemented a robust framework and strategy to ensure accountability and sustainability practices throughout its operations.

The company's climate-related risk management approach involves proactive risk assessment, incorporating climate change risks and opportunities into its enterprise risk management framework. The company has developed a comprehensive climate management plan to mitigate identified risks and ensure operational resilience in the face of climate change impacts.

Following the climate management hierarchy, the company prioritizes avoidance, mitigation, and offsetting efforts to manage emissions and align with broader environmental goals. Avoidance measures include portfolio screening and management, carbon pricing, risk management, due diligence, and engineering design philosophy. Mitigation efforts include flare and flash gas recovery, energy efficiency improvements, production optimization, and methane leak detection & repair. The company also emphasizes transparency, adhering to international standards, and disclosing relevant climate-related information to stakeholders.

The paper highlights the company's achievements, including surpassing its GHG emissions intensity reduction target eight years ahead of schedule. The company has successfully reduced emissions intensity by over 25% compared to the 2012 base year. The company's commitment to sustainability is demonstrated through its pursuit of net-zero GHG emissions by 2050, with interim targets in place for 2030 and 2040. To achieve this, they plan to deploy Carbon Capture, Utilization, and Storage (CCUS) technologies and support land and mangrove reforestation efforts.

Through partnerships with low-carbon technology providers and ongoing research and development, the company remains at the forefront of emission reduction strategies and actively contributes to global climate action.
Qualification and Deployment of a Nanocomposite Wellbore Sealant Water-Based Mud for Drilling a High Temperature Well
Authors: Kerkhoff Erik , Ismail Ahmed , Vlajie Mihai , Al Balushi Abdullah , Rekieh Aubyii
Published: October 2023

This paper describes the validation testing and field application of a nanocomposite wellbore sealant (NCWS) in a high temperature well. The inclusion of the NCWS in the high temperature water-based mud (HTWBM) exhibited tight and stable filtration characteristics, measured by high pressure high temperature (HPHT) and permeability plugging tests (PPT), as well as a notable reduction in drilling fluid viscosity.

The improvement in rheological profile reduced equivalent circulation density (ECD) and standpipe pressure (SPP).

A NCWS was identified during the well planning phase as the ideal technology for addressing the filtration and rheology.

A comprehensive suite of laboratory tests was performed to qualify the HTWBM formulation inclusive of NCWS performance, which included PPT and HPHT testing at 150°C. Rheology measurements were performed on a six-speed rheometer at 50°C.

The utilization of nanocomposite-treated water-based mud (NCWBM) resulted in notable enhancements in fluid performance as evidenced by the test results and when compared to offset salt polymer fluid formulations.

Hydraulic modeling showed reduction in ECD and SPP values using the NCWBM rheology results.

The NCWS was used in two wells, and fluid properties achieved exceeded expectations. The improved rheological profile was observed, which reduced the ECD and SPP values while drilling both wells.

The stability of the fluid proved consistent and easy to maintain over extended periods ranging from 22 drilling days on the first well to 39 days on the second well.

Wireline logging operations have been performed successfully, eliminating issues experienced on offset wells. Tight hole conditions while carrying out logging operations had increased the time required to successfully complete the data acquisition scope.

The inclusion of the NCWS in the HTWBM formulation resulted in some simplification of the fluid whereby two polymeric fluid loss additives were removed and the concentration of two additives was reduced by 50% and 75% respectively. The simplification of the fluid formulation resulted in more efficient logistics and lower inventory holding at the rig site, as well as a reduction in the lifting operations, and reduced manual labor required for mixing of the additives.

The NCWS was the key technology that developed the unique properties for the WBM. The NCWS is a proprietary nanocomposite suspension that provides enhanced sealing capacity to water-based drilling fluids. The additive is produced and applied as an emulsion and thus avoids the inhalation hazards associated with handling of dry nanomaterials (Jay P. Deville, Preston A. May, and J. J. Miller 2022; Fröhlich and Salar - Behzadi 2014).
Impact of Produced EOR Polymer on Production Facilities
Authors: Al-Murayri M. T. , Kamal D. , de Kruijf A. , Andrianov A.
Published: October 2023

Back-produced polymer to surface facilities is a significant topic in the literature due to the specific properties of the polymer, which are beneficial in the effective displacement of oil in the reservoir but could give challenges in the producers and surface facilities. This literature review addresses the impact of polymer on the key components of the production facilities ranging from artificial lift to the oil refinery and produced water disposal or reuse. The main polymer properties to interfere are (1) the ability to increase the viscosity of the produced water and (2) the precipitation of the polymer with constituents in water or process chemicals. These two properties could cause equipment failure, off spec quality of the oil and water, leading to oil deferment and increased maintenance. The magnitude of these challenges depends on the level of back-produced polymer. From the literature it is difficult to diagnose at what polymer concentration, insignificant impact is observed and when the production issues begin. It is recommended to analyse each key component individually and assess at what polymer concentration impact is expected in the operations. Important to identify is that an optimal polymer selection for the subsurface reservoir, might not be the right choice for the production facility. Therefore, early involvement of surface and chemical engineers is crucial to a successful polymer flood. This review will discuss a selection of the available literature addressing the main challenges and showing several examples. The content of a monitoring plan is discussed as well as the critical & additional analysis are given to properly understand the production side of a polymer flood and assist with mitigation strategies.
Paradigm Shift in Well Integrity Management Through the Use of Autonomous Wireless Well Intervention Robots
Authors: Guedes Julio Q. M. , Batista João H. G. , Souza Adriel B.
Published: October 2023

Traditional techniques to evaluate well's integrity employed for assessing mechanical integrity often come with high operational costs and logistical expenses, as they require the interruption of production or injection processes (1). Consequently, these conventional methods can be impractical and hinder overall efficiency.

However, the emergence of autonomous and intelligent intervention systems has paved the way for a significant advancement in this field. These innovative systems possess the capability to make real-time decisions in dynamic and unstructured environments. By using artificial intelligence technologies, it can autonomously evaluate mechanical integrity without human intervention.

One of the primary benefits of maintaining mechanical integrity is the assurance of safety and operational efficiency. The integrity of well structures prevents the occurrence of leaks, ruptures, or collapses, which can lead to catastrophic incidents and environmental damage. By employing autonomous and intelligent intervention systems, companies can proactively monitor the mechanical of wells, mitigating potential risks and avoiding costly operational disruptions.

These advanced systems are designed to monitor and assess critical parameters such as pressure, temperature, and flow. The real-time decision-making capability of autonomous intervention systems significantly reduces response times to potential integrity threats. By identifying issues, operators can prevent the escalation of problems and minimize associated costs. In addition to improving operational efficiency and safety, autonomous and intelligent intervention systems also offer long-term cost savings. By implementing proactive monitoring strategies, companies can optimize their resource allocation and extend the lifespan of wells. This, in turn, reduces the frequency of costly interventions and enhances overall operational profitability representing a significant leap forward in evaluating well's integrity. By reducing the need for traditional, costly techniques and enabling real-time decision-making equipment, these systems enhance safety, efficiency, and cost-effectiveness.

Studies (2, 3) demonstrates that the utilization of RLWI (Rigless Well Intervention) systems can significantly reduce the costs associated with well intervention. Also, the utilization of robotic solutions, as example, wireline tractors have been proved as an excellent solution to improve the efficiency and reliability of well integrity (4, 5, 6).

The paper will describe the progress made in developing a modular, autonomous mobile robotic platform for through-tubing operation. We outline the stages of prototype development, current project status, and tests. We also provide details on the artificial intelligence control and autonomous decision-making systems. Finally, we plan to present simulation and field test results in the final section of the paper.
Maturating Organic-Rich Source Rocks Using Superheated Gases Injection: Heat Transfer Analysis
Authors: Hassan A. M. , Alawad S. M. , Moh-Ali A. E. , Mahmoud M. A. , El-Husseiny A. H. , Abu-Mahfouz I. S.
Published: October 2023

Understanding unconventional formations is very important in order to improve the hydrocarbon production from these reservoirs. Different methods are used to increase the hydrocarbon recovery utilizing chemical injections. This study proposes a method for maturating unconventional shale formations using gases injection approach. The suggested method focuses on generating and improving gas production from immature and early mature organic-rich source rocks. The method comprises injecting superheated gases into the subsurface formation. The injected gases can maturate the organic matter due to the heat transfer between the high-temperature gases and kerogen. In this study, different superheated gases were examined including hydrogen, carbon dioxide, nitrogen, methane, steam, and air. Heat transfer analysis was carried out to investigate the impact of the injected gas on increasing the temperature of shale rock. Parameters such as injection velocity, rock density, and injection time were examined. Also, experimental measurements were carried out to capture the changes in organic and inorganic contents due to artificial maturation. The obtained results showed that the organic content can be reduced by around 8 to 33%, depending on the maturation conditions. The performance of the maturation treatment can be affected significantly by the temperatures of injected gases, treatment time, heating rate, gas type, and shale density. Among all examined gases, hydrogen and methane gases showed the highest maturation performance due to the fastest heat transfer. Also, increasing the kerogen density showed a negative impact on the maturation process by reducing heat transfer efficiency. Overall, injecting superheated hydrogen and methane gases at the maximum injection rate into shale formations of lower density would provide the best maturation performance.
Multi-Wave Joint Characterization Technique of Channel Sand Body in Shaximiao Formation, Northwestern Sichuan Basin
Authors: Wei Wei , Ran Qi , Chen Kang , Dai Junchen , Yang Guangguang , Yan Yuanyuan , Lv Yan , Xi Cheng
Published: October 2023

The channel sand bodies in the first member of Middle Jurassic Shaximiao Formation (Sha 1 Member) in the northwest Sichuan basin ZT area shows a vertically multi-period superimposed and horizontally contemporaneous crisscrossed. Meanwhile, it is highly non-homogeneous, with significant differences in sand thickness, porosity and gas content at different locations in the channel, resulting in complex and variable seismic reflection characteristics, which makes it difficult to accurately characterize the channel sand body distribution through a single amplitude 'bright spot' in the conventional longitudinal wave (PP-wave) post-stack seismic profile. In this study, the newly collected three-dimensional three-component transverse wave (PS-wave) seismic data in this area are used, combined with pre-stack and post-stack PP-wave seismic data, and based on the forward modeling, the multi-wave seismic response characteristics of the channel sand body are analyzed and summarized with the variation of sand body thickness and porosity, and a multi-wave joint channel sand body characterization technique is proposed for Sha1 Member of Saximiao Formation. The results of the study show that: 1. PP-wave seismic response of the top interface of the sand body gradually shifts from a strong wave peak to a strong wave through with increasing porosity, whereas the sand body response of the PS-wave does not reverse with porosity changes. The stability of the top interface of the sand body corresponding to the peak reflection of PS-wave, hence the lithological inscription based on the PS-wave amplitude attribute can effectively identify different types of river sand bodies. 2. Compared with the pre-stack P-G attribute, which reflects the PS-wave impedance changing rates, the PS-wave reflection amplitude shows better energy focus, and the boundary of channel sand body is also clearer based on PS-wave amplitude ‘bright spot’ compared with P-G attribute. While the P-G attribute based on the pre-stack seismic data has higher longitudinal resolution, thus it is more beneficial to distinguish the superimposed sand body and determine the phase of the sand body. In summary, the multi-wave joint sand body characterization technique makes full use of the advantages of multiple seismic data in sand body characterization, with the high-resolution P-G attribute helping to determine the longitudinal phase of the sand body, and the PS-wave used to map the transverse boundary of the sand body. The composite results can be used to provide a fine-scale characterization of the sand body in the main channel of Sha 1 Member. The application is highly effective and provides favorable support for well deployment and reserve upgrading in the Zitong area.
Next Steps in Hydraulic Fracturing in the Clair Field – An Evolving Story
Authors: Bird Anastasia , Roy Alistair , Tuffy Declan , Casero Alberto , Hoad James
Published: October 2023

Due to its complexity the Clair Field is a phased development. It consists of the Clair Phase 1 and Clair Ridge Platforms with prospects of Clair Phase 3 in future. The original development plan for the Clair Field was based on wells successfully targeting natural fracture networks to deliver enhanced production rates well above those the low-permeability matrix alone could deliver. Natural fractures drive productivity in Clair Field producers, so no hydraulic fracturing stimulation was envisaged. Therefore, it is unsurprising that initial stimulation efforts on the Clair Field targeted intervention-based hydraulic fracturing after the wells had been completed and put on production. However, several recent wells which did not encounter sufficient natural fractures have delivered production results below expectations. Consequently, this increased appetite for hydraulic fracturing to protect the base and provide additional production.

Hydraulic fracturing has demonstrated its value in terms of production uplift for the Clair Field since the first well was hydraulically fractured in 2019. The first platform-based multistage fracturing on the Clair Phase 1 Platform was undertaken from the drill floor when no development well construction was taking place. It has highlighted that fracturing offshore as a wellwork campaign is an intensive and complex scope.

On the Ridge platform the continuous drilling program is ongoing, driving requirements for simultaneous operations (SIMOPS). Increasing operational challenges to the next level, the next step was to perform hydraulic fracturing alongside an ongoing development drilling and completion campaign, driving the requirement to conduct all intervention operations simultaneously (SIMOPS) with minimal impact both to the rig and production operations. The first SIMOPS fracturing project was successfully delivered on the Clair Ridge Platform in 2022. It demonstrated the capability to perform a complex hydraulic fracturing intervention concurrently with an ongoing drilling campaign and production operations all while ensuring safe and reliable execution. Future intervention-based stimulations are planned on Clair Phase 1 and Clair Ridge and the lessons learned from the first two operations are key to delivering those efficiently.

Striving for continuous improvement, the Clair team have developed plans to transfer stimulation operations from an intervention to an integral part of the well construction phase, immediately following lower completion installation. Changing to an ‘online’ fracturing execution approach greatly reduces both equipment and personnel on board (POB) required on the platform.

New insights also include considerations on fracturing design and placement in naturally fractured reservoir as Ridge area of the Clair Field. This paper details lessons learned for dealing with pressure dependent leak-off for hydraulic fracturing in naturally fractured reservoir.
Skills for the Energy Transition and Beyond: Human Resource in the Industry 4.0 Energy Sector
Authors: Obode E. , Osunrinde T. , Ifalade O.
Published: October 2023

Industrial revolutions have been significant in shaping the modern world as we know it because it brings transformation across technology, economic and societal structures. Each revolution represents a shift in the way goods are produced, services required in production, labor and human capital dynamics and even daily life of society.

The question of whether revolutions indeed occurred historically has been subject of the works of revisionists and historians and there have been debates over the establishment of a timeline during which these events happened. This may have been because of the localization of the early Industrial revolutions. For this reason, arguments about what exactly changed, when it started, when it ended, and where to place the emphasis keep raging. Another reason for this contemplation is the drawn-out periods attributed to these revolutions. The retrospective presentation of Industrial revolutions may not necessarily paint the same picture as with people who lived through them without the benefit of hindsight. Four different schools of thought were thus identified as concerning what mattered or what changed during the Industrial Revolutions. The Social Change School, The Industrial Organization School, The Macroeconomic School and The Technological School. These schools have different areas of emphasis yet overlap to a point where clear line of distinction cannot be made1.
Essential Agreement to Get Robust Analysis of Production Logging in Horizontal Wells
Authors: Tveritnev A. , Kotlar N.
Published: October 2023

Understanding and predicting the behavior of multiphase flows from carbonate reservoirs is of paramount importance in oil and gas exploration and production. However, the complexity of these interpretations, often due to lack of agreement and variations in parameters for consideration, present significant challenges. Traditional techniques relying on the expertise of each analyst are often insufficient, necessitating the development of more refined workflow, particularly for horizontal and deviated wells where fluid dynamics introduce further complexity.

This paper elucidates a method for profiling multiphase flows in horizontal wells using array or Multiple Probe Tools, which provide distributed velocity and hold-up measurements across the pipe. This methodology improves upon conventional Production Logging (PL) interpretation, reducing the reliance on multiphase flow correlations and providing a more accurate understanding of the production or injection profile (Tveritnev,2023).

We discuss in detail the principles, calculations, and assumptions behind this method, its advantages over traditional approaches, and the impact of reservoir heterogeneity and fluid properties on the interpretation. Real-world examples and theoretical models are used to further illustrate the application of this approach, providing insights into the complex dynamics of multiphase flows in carbonate reservoirs. Finally, potential pitfalls and challenges in the interpretation of PL data are highlighted, along with solutions and recommendations for more accurate reservoir characterization.
A Novel Workflow Proposed to Calculate Net Carbon Intensity for EOR Applications in Giant Middle East Oil Reservoir
Authors: Garnier O. , Blanchet M. , D'Alessandro S. , Bourgeois M. , Prinet C. , Romero C. , Vaswani Y. , Aljaberi M. , Elbekshi A. , Al Saadi H. A. , Hegazy O. , Al Daghar K. , Alhammadi A.
Published: October 2023

ADNOC has the ambition to drastically reduce its net carbon intensity as part of its carbon neutrality (net zero) ambition by 2050. In simple terms, net zero means achieving an overall balance between the amount of greenhouse gases (GHG) emitted and those removed from the atmosphere. Net carbon intensity represents the GHGs from energy products and services provided by an Asset or a company, scopes 1, 2 and 3, net of negative emissions if any (e.g., CO2 permanent storage), divided by the energy produced by the company. It is a ratio which takes net GHG emissions and energy into consideration.

Reduction of net carbon intensity of oil production can be achieved through enhanced oil recovery (EOR) techniques. EOR technologies include CO2, polymer, and low salinity water injection, which can contribute to the reduction of carbon footprint. CO2 EOR has a potential to fully decarbonize ADNOC activities, especially in the onshore oil fields. CO2 can be collected from anthropogenic sources or from oil fields associated gas and injected into oil reservoirs not only to enhance the oil recovery, but also sequestrating the CO2 within the oil reservoirs. ADNOC onshore shareholders are sharing the same ambition to increase the annual volume of CO2 storage through EOR by more than 10 million tons per annum (MTPA). In any CO2 Water Alternate Gas (WAG) project, it is necessary to perform CO2 recycling after breakthrough. Estimating the EOR related GHGs emissions accurately includes calculating GHGs emissions related to the CO2 recycling operations with the additional oil production treatment, and the amount of stored CO2 after recycling.

The present publication introduces a novel workflow to perform EOR GHG emissions calculation, which can then be used to obtain the net carbon intensity of EOR technologies application The proposed paper is applied to different EOR applications (WAG CO2, Low salinity, and Polymer). The most impressive application case is WAG CO2 where the CO2 emissions are discounted by the CO2 stored thanks to EOR. The application of the EOR GHG incremental emissions has been done on a preliminary WAG CO2 project case with calculation of additional energy consumption, additional GHG emissions, CO2 storage, and, consequently, net oil carbon intensity (negative) and stored CO2 (positive). In this paper, EOR WAG CO2 results are discussed in detail.

The obtained results prove that EOR technologies can contribute to the reduction of carbon intensity of oil production. For the EOR CO2, the stored CO2 is not only compensating for the full scope 1 & 2 emissions linked to the EOR project, but also reducing the carbon intensity of the incremental oil production itself (scope 1, 2 & 3). Definition of scope 1, 2 & 3 can be found in the references.
Investigating the Effect of Geological and Engineering Parameters on the Fracture Height Growth in Naturally-Layered Shale Reservoirs Using 3D Lattice Method
Authors: He Rui , Zheng Youcheng , Chen Weihua , Lv Zefei , Zeng Ji , Yan Jie , Wang Tao , Wang Yang , Cao Aiwu
Published: October 2023

Numerical investigation of the influence of different parameters on hydraulic fracture propagation is fundamental to guide the fracturing parameters optimization of naturally-layered shale reservoir. The shale reservoir contains a large number of bedding planes with lower strength, which have a great effect on the vertical growth of hydraulic fractures. It is believed that the interaction between hydraulic fractures (HF) and bedding planes (BP) has a significant impact on the fracture geometry. In this paper, we used 3D lattice method to establish the hydraulic fracture modelling with multiple horizontal bedding planes, and this model can consider fluid-mechanical coupling effect and the fluid flow in permeable bedding plane. Based on the model, a sensitivity analysis of the key influencing parameters such as vertical stress, cohesion of bedding plane, permeability of bedding plane, injection rate, and fracturing fluid viscosity on the fracture height growth is implemented. The fracture penetration coefficient and the area coefficient of vertical propagation are introduced to evaluate the penetrating ability, and the degree of influence of each factor on the penetrating ability is analyzed and ranked using grey relational analysis (GRA). The simulation results show that the hydraulic fracture tends to penetrate bedding planes under the condition of high vertical stress, high cohesion of bedding plane, low permeability of bedding plane, high injection rate, and high fracturing fluid viscosity. Due to the existence of bedding planes, the morphology of hydraulic fracture is more complex, and the fracture shape presents several forms, typically including "I", "工", and "キ" shape. When the fracture penetration coefficient and the area coefficient of vertical propagation are higher, it is more likely that the hydraulic fracture penetrates the bedding plane directly. Otherwise, it will be arrested and turn to propagate along the bedding planes. Compared with other factors, the vertical stress has the most significant impact on the fracture height growth. The numerical model provides an effective approach for quantitatively analyzing the development of various types of HF/BP interaction behavior. The research results have been applied in hydraulic fracturing of Well X1, and expected stimulation effect is achieved by technical optimization.
Effects of Rock Heterogeneity and Wettability on CO2 Mineralization During Storage in UAE Depleted Carbonate Gas Formations
Authors: Fathy A. , Adila A. S. , Ahmed S. , Hassan A. M. , Al-Shalabi E. W. , Al Ameri W.
Published: October 2023

Anthropogenic CO2 emissions have accumulated significantly in the last few decades aggravating global warming. Mineral trapping is a key mechanism for the global energy transition during which injected CO2 is sequestered within the subsurface formations via dissolution/precipitation. However, the data of CO2 mineralization are extremely scarce, which limits our understanding of suitable candidate formations for mineral trapping. The aim of this study is to emphasize the impacts of wettability and rock heterogeneity on mineral trapping occurring during CO2 sequestration in carbonate formations. In this study, a numerical approach was followed by setting up one-spot pilot test-scale models of homogeneous and heterogeneous carbonate formations to predict the mineral trapping capacity of CO2 gas for two distinct wetting states: Strongly Water-Wet (SWW) and Intermediately Water-Wet (IWW). Accordingly, a 3D Cartesian base case model was created with upscaled petrophysical parameters to mimic the subsurface conditions of a representative carbonate formation from UAE. The study highlighted the relationship between carbonate wettability, rock heterogeneity, and fate of CO2 plume and mineralization potential.

In this study, the effect of wettability and heterogeneity were analyzed in terms of CO2 mineralized after 1 year of injection and 200 years of storage. The mineral trapping capacities computed showed a monotonic increase as the wettability shifted from SWW to IWW irrespective of reservoir heterogeneity with different extents. Notably, after 115 years of storage, the heterogeneous formations started to sequester more CO2 attributed to permeability variance increase. In the same context, plume of CO2 extended upwardly and laterally further in case of intermediately water-wet compared to strongly water-wet, especially at earlier stages of storage duration. Classical trapping mechanisms such as solubility trapping gained more attention than mineralization. This is attributed to the time-dependency of mineralization with slow reaction rate scaling up to millennia. Thus, CO2 mineralization potential assessment is important to de-risk large-scale pilot tests. This work provides new insights into underpinning the effects of wettability and rock heterogeneity on CO2 storage capacity in carbonate formations. The findings suggest that mineralization within carbonate immobilizes CO2 and thus, assists in stable and long-term storage.
Large-Scale High-Throughput Sensitivity Analysis of CO2 MMP to Optimize Gas Injection EOR Processes
Authors: Abedini A. , Qi Z. , Haas T. de , O'Brian D.
Published: October 2023

Performance of CO2 injection relies on accurate CO2 MMP/miscibility data at reservoir conditions. The CO2 stream typically contains gas impurities, and in most cases CO2 is combined with recycled gasses, which in either case the MMP changes – imposing additional uncertainties to deviate from expected CO2-MMP. Slim-tube is the most reliable tool; however, it is very time- and capital-intensive, making it impossible to provide high-throughput data to assess the impact of other gasses. Throughout a case study, we present a very efficient microfluidic platform to measure high-quality MMP data of CO2 with various impurities significantly faster and easier. In this work, a microfluidic platform was designed and used to determine the MMP/miscibility condition of CO2 in pure state and with several impurities (i.e., hydrocarbon mixtures, CH4, H2S, H2, N2, Ar) for an EOR operation in a depleted reservoir. 18 miscibility tests were conducted over ∼4 weeks to provide detailed data on how the MMP or miscibility of CO2 changes due to gas impurities – possibly the largest and fastest empirical study of MMP sensitivity ever. A high-resolution fluorescence microscopy along with an automated image analysis algorithm were employed to assess the miscibility condition. The MMP of a few gasses were also measured using the slim-tube to verify the validity of the microfluidic measurements, showing a tight agreement between the data. The results have demonstrated a reliable, accurate, and quick method to conduct a thorough CO2-MMP sensitivity analysis for gas injection processes. While each impurity may have a clear impact on the MMP, either in an increasing or decreasing manner, the interconnection between multiple impurities is generally unknown and differs as a function of impurity composition and reservoir conditions. The outcome of this work, eventually, gave a roadmap to provide a boundary of a miscible zone, in which the level of impurities is acceptable and not adversely affecting miscibility performance of injection, and while beyond this boundary, the impurities may negatively impact the recovery from performance of gas injection by increasing the MMP above the current reservoir pressure. Given the very small volume of oil sample, easier operations, and faster run-time required for this microfluidic approach, the miscibility/MMP study of a testing oil with various gas compositions can be determined in days – not obtainable with the slim-tube approach. The microfluidic platform utilized here provides accurate and quick gas injection related miscibility information, that can potentially open a new opportunity to better develop the current resources, improve the production efficacy, and mitigate uncertainties associated with gas injection plannings and operations. The benefits can be further extended for facility design, regulatory requirements, land acquisition strategy, workflow modifications, and reserve estimates.
Effects of Pressure on Oil Thermal Cracking: Insights on the Data from High-Pressure Optical Cell (HPOC) Experiments
Authors: Chen Yanyan , Tao Shizhen , Ma Ning , Li Yahui , Tao Xiaowan , Gao Jianrong , Lv Wanjun , Wei Lin
Published: October 2023

The role of pressure in the thermal cracking of crude oil are still under debate. In this study, a novel method employing high-pressure optical cell (HPOC) and fluorescence spectrometry was used to in situ monitor the thermal cracking of oil under elevated temperatures and pressures, and investigate the effects of pressure. Specifically, two HPOC cells loaded with crude oil samples were simultaneously heated on the same heating-cooling stage but at different pressures (i.e. 30 MPa and 100 MPa). Changes in the attributes of pyrolytic products (i.e. physical appearance, fluorescent colors and intensity, etc.) were real-time recorded. The fluorescence spectra were measured every half hour to semi-quantify the chemical evolution of pyrolytic products.

The results showed that the fluorescent color of pyrolytic products generated at 100 MPa evolved from blue to greenish yellow as heating, and finally turned to yellow at the end of pyrolysis experiments. In contrast, the fluorescent color in the 30 MPa cell finally turned to deep blue, instead of yellow, after 12 hours’ heating. A light blue bubble of primarily light, gaseous cracking products was observed after 5 hours’ heating at 30 MPa, whose volume expanded and finally filled up the whole cell. In contrast, no such bubbles were observed in the 100 MPa cell.

The λmax values derived from fluorescence spectra shifted initially toward longer but later toward shorter wavelengths in the 30 MPa cell (i.e. an initial redshift followed by a later blueshift), distinctly contrasting the evolutional pattern of monotonically shifting of λmax toward longer wavelengths as observed at 100 MPa (i.e. a constant redshift). The red-green quotient (Q =I650/I550) based on the λmax values can be used to semi-quantify the thermal maturity and stability of chemical substitute. The smaller Q values in the 30 MPa cell clearly suggested that the chemical compounds in the 30 MPa held higher thermal maturity and probably subject to a more intense thermal cracking.

The distinction between optical, physical, and chemical properties of pyrolytic products at different pressures are direct evidence proving that high pressure can hinder the thermal cracking of oil to gases. Therefore, the burial depth range at which petroleum can still remain as liquid phase might be extended at high pressure, which is vital for the establishment of exploitation strategies of deep reservoirs a high pressure.
Multi-Scale Sedimentary Forward Reservoir Modelling: A Disruptive Solution for Simulating Heterogeneity in Carbonates. Application to the Kharaib-2 Reservoir Unit
Authors: Massonnat G.J. , Michel Julien , Gatel Pierre , Ruiu Jérémy , Danquigny Charles , Lesueur Jean-Louis , Jean-Borgomano
Published: October 2023

In mature hydrocarbon provinces, the intense operational activity on each field to monitor production through drilling and work-over operations, as well as the continuous updating of the reservoir models that drive these operations, leads each asset to concentrate its efforts on work at the scale of the field for which it is responsible. This focus is consistent with both data acquisition, which is targeted on the zones of interest, and with the restrictive use of this data prior to the modelling phase. By giving priority to statistics (Vertical Proportion Curves, occurrence tables between facies and rock-types, distributions of petrophysical variables, etc.), data analysis before modelling favors an understanding of reservoir heterogeneity at the scale of the field, to the detriment of a more regional understanding. Reservoir modeling techniques, which to date are essentially geostatistical, also maintain this focus on data rather than knowledge. By failing to challenge the relevance and the consistency of the geological concept used to apply interpolation techniques, the geostatistics-based modelling process deprives the user of the opportunity to validate or invalidate a number of assumptions that are nonetheless crucial in terms of model outcomes (Borgomano et al, 2020).

On the other hand, effectively integrating at the regional scale the stream of data coming from the different fields would require a common framework and unifying concepts. In vast regions such as the Middle East, the size and density of wells in each field relative to the distance between fields makes it tricky to create this truly integrative framework. Synthetic or a selection of representative logs are thus used to build regional models. The distances between fields larger than the range of any variogram make also geological processes the only possible unifying concepts. Thus, geological models should be built by simulating the geological processes at the regional level and including several fields, in such a way as to be consistent in terms of geology, with little dependence on available data, and with a variable resolution adapted to needs and constraints. In the absence of such models, forecasting in prospective areas is always uncertain, even during intensive exploration.

One of the major challenges of geological modelling is currently to test and validate at the regional scale the concepts used at the reservoir scale, to capitalize in regional models the detailed knowledge gathered in the fields, and to bring into reservoir models the regional understanding after validation. The disruptive approach presented in this paper addresses this issue, with a first application on the Kharaib-2, a carbonate reservoir unit from the Middle East.
Short-Term Production Optimization in a Time-Dependent Parameters Scenario
Authors: Parravicini M. , Montini M. , Vignati E.
Published: October 2023

Although the pandemic has slowed the entire world for some years, the energy demand is nonetheless set to increase significantly in the coming years, mainly driven by the expectation of an increase in prosperity in the developing world. Renewable energy is expected to play a major role as the main source of energy. Nevertheless, oil and gas production is supposed to remain a key player in the energy scenario with natural gas consumption constantly increasing and oil consumption peaking in 2030.

Lately, the world has found itself in the midst of its first global energy crisis - a shock of unprecedented breadth and complexity triggered by Russia's invasion of Ukraine following rapid economic recovery from the pandemic. This uncertain scenario caused oil and especially gas prices to skyrocket in 2022, reaching levels never seen before and characterizing the whole year as a year of record profits for most of the oil and gas players across the globe. This, in turn, caused a oil and gas upstream capital expenditures increased by 39% in 2022, the highest level since 2014.

However, estimates say that additional investment are still needed to ensure adequate supplies in the future, investments that are still uncertain to be granted at the horizon.
Transformation of Operations Through Digital Twin Application
Authors: Almessabi Ahmed , Al-saedi Khaled , U Ddin Muhammad , Al Naqbi Mohammed
Published: October 2023

The world is now witnessing a fourth industrial revolution with the rise of artificial intelligence and Digital Twin technology. The Oil and Gas industry, a pillar of global energy supply, has always been driven by cutting-edge technologies and innovative solutions to meet the ever-increasing global demand. In the quest for operational excellence and heightened productivity, O&G companies are now turning their attention to a revolutionary concept - Digital Twins.

Emerging as a significant component of industry 4.0, Digital Twin technology offers a powerful and transformative approach that holds immense potential for large scale organizations. The Oil and Gas Industry is one of many industries that are currently adopting this new technology to improve their safety, operational efficiency, production and decision-making measures.

When considering the fact that concepts such as data acquisition and modeling, visualization, simulation, real time monitoring and predictive control are not new to the Oil & Gas industry, leveraging digital twin technology seems like the natural step forward.
Analytical Method and Approach on Early Warning Indicators for Enterprise Capital Project Management
Authors: Baharom Ts-Muhammad Azri Ahmad , Abdullah Asrul Sani
Published: October 2023

Executive Summary

Effective project monitoring and control are extremely critical for the successful delivery of projects, especially for a Project Management Office (PMO) overseeing a significant numbers of capital projects. Applying Early Warnings as part of the process allows PMO at enterprise level to identify projects with emerging risks before performance thresholds are breached, allowing for proactive mitigations, optimization of resources and preservation of value. This paper discusses the Early Warnings concept, followed by descriptions of the analytical approaches and methods used during the development of Project Early Warning Indicators (PEWI) system in PETRONAS for Enterprise Capital Project Management. Finally, the paper discusses the challenges and advantages as well as the opportunities for further improvements.