bluuebunny/crossref_metadata_2025_split huggingface dataset:
Personnel Real Time Tracking in Hazardous Areas Using Wearable Technologies and Machine Learning
Authors: AL-Qutami Tareq Aziz , Awis Fatin Awina 
Published: March 2021

Abstract
Real-time location information is essential in the hazardous process and construction areas for safety and emergency management, security, search and rescue, and even productivity tracking. It's also crucial during pandemics such as the COVID-19 pandemic for contact tracing to isolate those who came to the proximity of infected individuals. While global positioning systems (GPS), can address the demand for location awareness in outdoor environments, another accurate location estimation technology for indoor environments where GPS doesn't perform well is required.
This paper presents the development and deployment of an end-to-end cost-effective real-time personnel location system suitable for both indoor and outdoor hazardous and safe areas. It leverages on facility wireless communication systems, wearable technologies such as smart helmets and wearable tags, and machine learning. Personnel carries the client device which collects location-related information and sends it to the localization algorithm in the cloud. When the personnel moves, the tracking dashboard shows client location in real-time.
The proposed localization algorithm relies on wireless signal fingerprinting and machine learning algorithms to estimate the location. The machine learning algorithm is a mix of clustering and classification that was designed to scale well with bigger target areas and is suitable for cloud deployment.
The system was tested in both office and industrial process environments using consumer-grade handphones and intrinsically safe wearable devices. It achieved an average distance error of less than 2 meters in 3D space.
Integrating PVT, Stable Isotope and Biomarker Geochemistry and Pressure Data to Characterise the Continuity of a Geologically Complex Gas Condensate Reservoir
Authors: Bestman Somiari , Ghassal Bandar.I. I , Attar Ahmed , Kabir Akim 
Published: March 2021

Abstract
Characterizing reservoir continuity is a critical part of the field appraisal and delineation process and it carries an inherent risk for all stakeholders as well as significant implications for field development planning. The risk becomes even more substantial when planning the development of a geologically complex marginal field. Uncertainty and risk analyses are carried out in order to assess the potential impact of various parameters including geological uncertainties. However, the efficacy of the uncertainty and risk analyses processes are dictated by the quality and quantity of the available data. Thorough and extensive data collection and analysis, incorporating channels such as insitu reservoir fluid sampling, reservoir fluid characterization, molecular geochemistry, stable isotope geochemistry as well as pressure data will improve the outcomes of the uncertainty and risk analyses while minimizing reservoir continuity mischaracterization risks.
Challenges and Solutions for Conductor Sharing Technology with Higher Specification Conductor to Meet Target Fatigue Life
Authors: Khor Guan Han , Razali Ezuan Hanafi , Musa M. Idham , Mat Isa Saifol Anuar , Wan Hasan Wan Helmi , Chang Daryl 
Published: March 2021

Abstract
Since Conductor Sharing Technology became prominent in the 1990s, the technology has evolved to accommodate the associated well design and construction complexities. In the redevelopment of Brownfield "S", under an alliance between PETRONAS Carigali and other operator, the technology has enabled the number of potential new wells to be increased. However, the technology has been constrained in terms of the available conductor and casing size options. The objective is to advance the current technology to meet the well design and construction requirements.
This paper presents the challenges and solutions for conductor sharing technology to accommodate a higher specification conductor (36"×1.5" wall thickness), which is required to meet the fatigue life requirement in Field "S" Phase 3 redevelopment project. Since mid-2018, when PETRONAS took over the operatorship, further conductor analyses have been required. These studies confirmed the requirement for 36" conductor with 1.5" wall thickness, to meet the target fatigue life of 20 years. This paper focuses on a range of key engineering considerations related to well construction including geometrical separation, integration between CWD (casing while drilling) and directional, cementing, and diverter requirement to CWD surface casing.
Since there is no existing system that can accommodate this wall thickness and still be able to meet the well construction requirements, a collaboration with the equipment provider has led to the design and manufacture of the world's first splitter wellhead system used for 36" (1.5" WT) × 13-3/8"(2X) × 9-5/8"(2X) × 3-1/2"(4X) with 10,000 psi working pressure rating. The splitter wellhead has allowed two infill wells to be drilled and completed on Platform "A". The system has maximized oil recovery with the additional well. The successful installation and production from this wellhead provide opportunity to reduce construction cost and maximize utilization of existing well slots for future development of brown fields.
The improved technology has created more value by allowing surface casing to be installed by CWD in directional sections and the cementing program to be enhanced under diverter system. This solution will be beneficial to similar brown fields which have limited remaining slots and where it is unjustifiable to construct a new platform. In addition, it provides opportunity to lower the wellhead platform cost for green fields by optimizing the number of well slots and platform design.
Maximising the Value of Multi-Sensor Streamer Data via MAZ Processing
Authors: Zhang Hui , Yao Jianfeng , Li Xiang , Zhao Kai 
Published: March 2021

Abstract
The North West Shelf of Australia contains a late Paleozoic to Cenozoic sedimentary succession, which attains a thickness of over 10 km and is dominated by Triassic to Lower Cretaceous sediments. The deeper plays exist at multiple stratigraphic levels including oil-prone Jurassic sediments and faulted gas-prone Triassic sediments. The area has been proven difficult as far as seismic imaging is concerned, particularly over the Madeline trend. The presence of a hard, rugose water bottom, strong reflectors beneath the water bottom, and shallow Tertiary carbonates make the Dampier Sub-basin vulnerable to multiple contamination, amplitude distortion, lower signal-to-noise ratio (S/N) and unreliable AVO response. Poor seismic quality in the data has been a significant barrier to reducing exploration risk. In the 1990s, East Dampier (1992, blue polygon in Figure 1) and Keast (1997, yellow polygon in Figure 1) seismic data were acquired in East-West and North-South directions respectively, in an effort to better understand the impact from the shallow complex overburden. To address these challenges, the Demeter survey was acquired in 2003 (black polygon in Figure 1) with a denser acquisition grid. The overall seismic quality was improved, but the results still contained a significant level of residual multiples. Later, the Fortuna survey, the most comprehensive multi-sensor seismic survey on the North West Shelf of Australia to date, was acquired in 2014 with the aim to provide better subsurface imaging (pink polygon in Figure 1) from different acquisition perspectives. The data was processed with advanced processing technology, including shallow water demultiple, deghosting and high definition tilted orthorhombic velocity model building (Birdus et al., 2017). However, the final results were still suffering from a number of challenges, specifically: 1) strong residual multiple in near offsets, 2) low S/N ratio, particularly at reservoir level, and 3) inconsistency from near to far stack resulting in unreliable AVO.
In this paper, the Dixon area (green polygon), considered as the most challenging area in the Dampier Sub-basin, was chosen as the testing area for our work. By integrating high-end imaging technology, for example dual-sensor deghosting, multi-survey surface related multiple elimination (MAZ-SRME), and multi-azimuth processing (MAZ stack), we will illustrate how we have overcome many of these imaging challenges.
First Successful Installation of Through-Tubing Ceramic Sand Screen in Seligi Oil Field, Offshore Peninsular Malaysia
Authors: Kadir Masran , Rusli Muhammad Ruzwin , Samsudin Bukhari , Rahman Saim , Norizan Sheereen , Wee Thierry , M. Johan M. Alham , Al Zayani Sirag , Roslan Mohd Razeif , Mahadi Khairul Azmi , Salleh Muhammad Zulkhairi 
Published: March 2021

AbstractThe Seligi field, located 240 kilometers offshore peninsular Malaysia in the Malay basin was discovered in May 1971 and is one of the largest oil fields in Malaysia. Sand production in the Seligi field has been observed, especially from the J reservoirs group. Within the Seligi field, Well G was identified as one of the wells with sand production to surface that could lead to sand accumulation at surface facilities and erosion of equipment. Historically, there had been no in-situ sand control measures in the well. The default practice for sand control was to choke back the well, to prevent triggering of the surface sand probe (production with maximum sand-free rate). This approach however is a compromise, while it limits sand production, it also limits the production potential of the well (well technical potential). As part of the production enhancement assessment program, remedial sand-control methods were considered to increase the oil production while minimising sand production. Among the options considered was ceramic downhole sand screen installation. Ceramics have been used in many extreme erosion and corrosion applications, with ceramic sintered silicon carbide being 50 times harder than steel. Ceramic sand screens made with sintered silicon carbide offer much higher erosional resistance at speeds of 300ft/s sand impingement velocity. Due to the aggressive nature of the sands and high velocities of greater than 50ft/s in Well G, a through-tubing ceramic sand screen was selected. The ceramic sand screen served as a fit for purpose solution that allowed the well potential to be fully maximised, enabling a continuous production with minimal sand production at surface.This paper reviews the first successful pilot installation of through-tubing ceramic sand screen in Well G in the Seligi Oil Field, Offshore Peninsular Malaysia. Discussed are careful analysis and planning, i.e. velocity calculations, tool deployment simulations, tool inspections and detailed job procedure leading to a successful installation. With the ceramic sand screen installed, the well was able to produce at 100% production choke opening with lower tubing head pressure and has not produced sand at surface despite multiple shutdowns and well bean ups. The installation has also removed the need to have sand handling facilities at topside and has generated an implicated cost saving from expensive intervention programs. Given the success of this pilot installation, a baseline in sand control has been set for this field, with new well candidates being considered for future replication.
Buried Strike-Slip Fault Identification Technique Based on a 3D Stress Body Attribute Considering Formation Deformation and Lithologic Variation
Authors: Wang Wei , Wu Kui , Kang Lin , Huang Xiaobo , Yao Jian 
Published: March 2021

Abstract
The identification and interpretation of buried strike-slip faults are of great significance int the search for structural traps in oil and gas exploration. However, it is difficult to identify and interpret buried strike-slip faults from seismic profiles and variance slicing, because they may be clear at depth but vague in the shallow. This study proposes a 3D stress body attribute taking into consideration formation deformation and lithologic variation to identify buried strike-slip faults. Taking into account thin plate theory and the generalized Hooke's law, a relationship between stress field, formation deformation and lithologic variation is established. Structural curvature body is used to represent the formation deformation, which is obtained by scanning of the body dip angle and second-order derivation of the wave number domain, while Poisson's ratio and Young's modulus volumes are employed to reflect the spatial lithologic variation, which are calculated by the multivariate linear fitting method or prestack inversion. This technique is applied to the secondary structural interpretation of JinZhou 25-1 oilfield in LiaoDong Bay depression of BoHai Bay Basin. Compared with the 2000 ms variance slice, it can be seen clearly that there is a significant stress concentration zone in the location of LiaoXi buried strike-slip fault from the 3D stress body attribute slice, which is consistent with a sudden change in strata observed on the profile. The LiaoXi buried strike-slip fault has been identified and interpreted. Many structural traps greater than 20km2 have been found along its course. Among them, W structure was drilled in 2016 and about 4.5 million tons of oil was found. This suggests that the spatial distribution of buried strike-slip faults associated with tectonics can be effectively identified through the strength property of the stress field, which is greatly superior to the conventional variance-related methods. It verifies the ability of this technique in the identification and interpretation of strike-slip faults in the entire Bohai Bay Basin and thus its potentially critical role in guiding secondary seismic interpretation.
Four-Dimensional Geological Modeling of Stress-Sensitive Reservoirs of Abnormally High-Pressure Carbonates
Authors: Chen Yefei , Li Kongchou , Ni Jun , Hou Qingying 
Published: March 2021

Abstract
The abnormally high-pressure carbonate dual-medium reservoir of the Kenkiyak Pre-salt oilfield in the littoral Caspian Basin has strong stress sensitivity. With the development of the oil field, the formation pressure drops and the fractures gradually close, resulting in a decrease of the effective permeability of the dual-media reservoir over time. So it is necessary to establish three-dimensional geological models of the dual-medium reservoirs at different times, which is the 4-D geological model.
Firstly, the reservoir matrix and fracture permeability model under the original conditions is established by using the dual-medium three-dimensional geological modeling method; Secondly, the formation pressure model for a given period is established by taking the measured well-point formation pressure in a certain period as hard data and combining with the formation pressure change trend in different zones; Thirdly, the carbonate reservoir types are identified by borehole imaging and conventional logging, and the geological model of the reservoir types in the original state is established. Finally, using the relationship between confining pressure and permeability reduction rate of different types of reservoirs obtained by core stress sensitivity experiments, and based on the original matrix and fracture permeability models, the matrix and fracture permeability models of different types of reservoirs at a given period are obtained.
Using the method proposed in this paper, the original matrix and fracture permeability model can be corrected to the matrix and fracture permeability model after the formation pressure drops at a certain period, and the 3D geological model of carbonate reservoir in any given periods can be obtained. Newly drilled wells at present confirmed that the geological model established by this method is reasonable and reliable. Taking the data of new wells completed during this period as hard data and the above three-dimensional geological model as soft data, an updated dual-medium model is established, which is more in line with geological reality. Based on the updated geological model, the deployment of oilfield adjustment schemes and well location optimization studies are carried out. The match between the new drilling data and the prediction results reached more than 90%.
The method solves the problem of updating the 3D geological model caused by the permeability change of the stress-sensitive reservoir, ensures that the geological model truly reflects the underground geological characteristics, and can be widely applied to the 3D geological modeling of stress-sensitive reservoirs.
Research and Application of Segmented Acid Fracturing Technology in Horizontal Wells of Ultra Deep Carbonate Gas Reservoirs in Southwest China
Authors: Wang Yang , Zhou Changlin , Zhang Huali , He Tingting , Tang Xinyuan , Peng Huan , Fang Hongming , Luo Le , Gang Shu 
Published: March 2021

Abstract
The Shuangyu gas reservoir in Southwest China is a fracture ultra deep carbonate gas reservoir. Its reservoir buried depth is more than 7000m, and the reservoir temperature is about 160°C. In the early stage, the vertical well acid fracturing method was used to obtain the natural gas production, but the gas production decreased rapidly after acid fracturing, which is difficult to achieve economic and efficient development. Segmented acid fracturing of horizontal wells is an effective way to greatly increase gas production. However, segmented acid fracturing of horizontal wells in Shuangyu ultra deep carbonate gas reservoir faces the following problems: (1)High reservoir temperature, fast acid rock reaction speed and short length of acid corrosion fracture. (2) The diameter of horizontal well is small (114.3mm), packer and other tools can not be put into the wellbore.
In this paper, through laboratory tests, an acid fracturing fluid with temperature resistance of 160 °C and friction resistance of 35% of water is developed. The fracturing fluid has the characteristics of high viscosity and high concentration of hydrogen ions, which can not only fracture the formation, but also carry out effective acid etching on the fracture during the injection process. Through the experiment, the temporary plugging agent which can meet the temperature of 160 °C and the combination of temporary plugging agent can form a sealing layer in the fracture with the width of 4mm, and the maximum sealing pressure can reach 20MPa. The research results have been successfully applied in well y616. After fracturing, the daily output of natural gas in well Y616 is 1 million cubic meters, which is more than three times that of the surrounding vertical wells.
Coring not Boring
Authors: Ashqar Ayham , Razak Amin , Ramly Noor Faezah , Dahlan Nur Athirah , Jamaludin Junirda , Karim M. Azan 
Published: March 2021

Abstract
Coring and core analysis are considered the only direct and physical data to provide a true reflect to the reservoir properties. The measured properties are used to calibrate subsurface models and ensures close to reality properties. Representative data is critical to allow achieving such target.
Coring planning and close follow up from the day decision is taken to core is important to achieve representative data.
The approach followed in this manuscript allowed a high probability of successful core cutting, and representative core analysis.
Field A is planned for appraisal phase and reservoir is expected to be of low permeability with sequence of shaly sands which adds complications to achieve the objective in cutting and analyzing the core. Different coring technologies were evaluated against the main coring objective of potential hydraulic fracturing field development. Conventional core is selected to offer the best value in both cost, and data coverage in compare to sidewall core. However, due to financial impact only one run was allowed, consequently it was critical to get the highest possible recovery and highest quality in one shot.
An extensive planning phase investigated all variables to ensure high recovery. Rock strength and its mechanical properties allowed the selection of optimum coring parameters, coring accessories, and coring bit. It is critical to the project to collect the core and the added challenge of only single run required detailed workflow. Borehole size, mud wt, rate of coring and coring parameters were challenging due to the given one time opportunity.
As a result, successful 100% core recovery is achieved, core retrieval to surface ensuring least core damage, this is demonstrated by CT scan which indicated no tripping out induced fractures. Well site core preservation reduced any weathering alteration, the selected stabilization method allowed minimal invasive to the core. Electrofacies guided by the whole core CT scans allowed the best coverage to the reservoir's properties. Long and large diameter plugs were achieved. Cleaning pilot study facilitated the selection of least damaging cleaning and drying method. Pilot small core analysis programs, and close follow up, and the analysis of raw data reduced the risk of unrepresentative core analysis results. Conventional core analysis data allowed refining and enhancing premeasurement electro facies and allowed a distinctive rock typing. The detailed planning permitted us to secure 100% core recovery and ensured core is reached the surface with least possible damage. The followed core analysis strategy reduced redundant experiments and allowed representative results at the same time optimized on the cost.
This paper demonstrates the best practice that is followed in challenging environment of shaly sand sequences to successfully cut core and develop a program, and workflow which reflects the uncertainties to be solved.
Cyclonic Separation Technology for Sand Management – Challenges and New Development
Authors: Shaffee Siti Nur , Che Daud M. Faizal , Myo Thant Maung Maung , Norpiah Rohaizad M. 
Published: March 2021

Abstract
Cyclonic devices are ubiquitous in industrial processes and have been used for particle separation for decades. However, designing a highly efficient, compact cyclone for erratic flow conditions and particles of varying types, sizes and density remains a challenge. This paper aims to present the challenges, lessons learnt and recent development in cyclone technology for solid separation.
Primarily, a discussion on typical cyclonic desander geometries is conducted. Failures and sub-optimal operation of cyclonic wellhead desanders within the company are analysed, and subsequently the failure mechanisms and factors leading to inefficiencies are identified. Computational Fluid Dynamics (CFD) simulations and flow loop testing are further performed to verify the particle separation efficiency and quantify the erosion risks of the typical cyclone geometries.
The typical cyclonic geometries are considerably less efficient in multiphase-flows compared to the gas-solid or liquid-solid flows. As a result, the overflow section of the cyclone often contains particles larger than the design specification. Changing operating envelope over time, for example, reducing production and changing flow regime affects cyclone efficiency over time. Based on a systematic analysis of the desander failures in the fields, a few design improvements have been proposed to overcome these limitations, resulting in a novel technology. This new cyclonic technology with multiple barrier system can successfully maintain the 98% target removal of 10microns particle under erratic multiphase-flows conditions. Furthermore, it can be designed to handle various types of particles e.g., sands, HgS and other solids. The versatility of this system provides promising technology for ageing fields with excessive solids production.