bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Transport Mechanism of Proppant in Rough Fractures in Unconventional Reservoir
Authors: Jin Ting , Dong Yifan , Yang Shengfang , Zhang Yuelong , Wang Lei , Shao Yinan , Zhang Ning 
Published: February 2025

Abstract
Proppant distribution within fractures is a crucial factor in enhancing the production from fracturing. Currently, most studies on the transport and settling behavior of proppants in fractures are based on the models of smooth, straight fracture. There is rarely research considering the effects of fracture tortuosity and roughness on proppant movement and settling. To further reveal the trends of proppant transport and setting in tortuous and rough fractures, physical experiments were conducted to observe proppant behavior in smooth and flat fractures firstly. Based on this, established tortuous and rough fracture models to explore proppant movement and settling patterns. Results indicate that larger proppant particle sizes are more conducive to settling within smooth plate fractures, and medium-to-large particle proppants are more likely to accumulate near the branch fracture entrances. For smooth-plate fractures, the increased the injection rates will allow proppants to penetration deeper into both main and branch fractures. For tortuous rough fractures, larger proppants are more impacted by fracture structure, often accumulating in the middle sections and causing blockage; however, increased injection speeds can effectively mitigate these blockages. These findings reveal the influence of various operational factors on proppant transport and settling, offering theoretical guidance for optimizing hydraulic fracturing techniques.
Countdown To CCS - The Monitoring And Surveillance Of High CO2 Sarawak Offshore Field
Authors: Manaf M. A , Dasuki N. A. , Bidin L. A. , Othman A. I. , Shata K. A. , Berok S. M. James , Hameed J. 
Published: February 2025

Abstract
An offshore gas field with a high CO2 content was developed with the plan of storing the CO2 in a nearby depleted field as a Carbon Capture and Storage (CCS) initiative. The performance and therefore production data of the field is crucial to ensure the overall success of the project. Thus, before the commencement of CCS, a robust monitoring and surveillance plan of the field’s performance and contaminants must be in place.
To achieve this objective, a 5-year plan of monitoring and surveillance was devised specifically for the high CO2 field. Additionally, a literature review of Monitoring, Measurement and Verification (MMV) for CO2 storage in general, as well as a review specific to the storage site, were extensively conducted. Finally, an Integrated Asset Management (IAM) platform for real-time monitoring of well and equipment parameters, was built for the field to facilitate faster analysis and troubleshooting.
For the high CO2 field, a Data Acquisition (DA) outlook which included but not limited to Static Gradient Survey (SGS), Pressure Build Up (PBU), reservoir saturation logging, and wellbore inner diameter evaluation was planned that could help with field performance and integrity analysis. From the literature review on MMV, the storage site must have special considerations of monitoring and surveillance due to the high CO2. For the daily monitoring and surveillance, the IAM proved to be invaluable to give real-time data and timely intervention.
The monitoring and surveillance of the high CO2 offshore field are using both the conventional as well as customized tools and techniques. This is to ensure robust preparation for the CCS project and can be a benchmark for similar endeavors in the future.
Intelligent Diagnosis of Electric Submersible Progressive Cavity Pump Based on Multiple Parameters
Authors: Ma Gaoqiang , Shi Junfeng , Chen Xuehui , Lan Fang , Zhao Ruidong , Zhang Xishun 
Published: February 2025

Abstract
The Electric Submersible Progressive Cavity Pump (ESPCP) is an innovative rodless lifting technology that uses cables to propel downhole PCP, effectively reducing issues like rod-tubing deflection and improving transmission efficiency. While traditional methods rely on specialized ground electronics for assessing ESPCP working conditions, these methods often lack precision for accurate diagnosis in intricate conditions. The ongoing trend of well digitization has led to ESPCP wells equipped with ground electronics and downhole multi-parameter acquisition systems. However, academic discussions have not adequately explained the influence of these parameters on working conditions. This study addresses the challenge of low diagnostic accuracy in relying solely on ground electric condition and the absence of diagnostic technology utilizing multi-parameter data. A 10-parameter sensitivity analysis model is developed to incorporate ground electric current, downhole temperature, pressure, and vibration. The research elucidates the interplay of multiple parameters under varying working conditions, identifying 6 key control factors including oil pressure, casing pressure, rotational speed, power, pump suction pressure, and pump temperature. By conducting fourth-order partial correlation analysis, the study quantifies the impact of each parameter and the primary correlation parameters across different operational scenarios, establishing a comprehensive multi-parameter synergistic change model for various working conditions. Focusing on the main correlation parameters of typical operational states, temporal characteristics are extracted from time, frequency, and time-frequency domains to serve as input data for a Long Short-Term Memory (LSTM) neural network model. This intelligent diagnostic approach for ESPCP wells, based on multi-parameter working condition analysis, has been successfully implemented in 50 oilfield wells. The diagnostic accuracy has significantly increased from less than 80% to over 92%, demonstrating the potential for precise control of ESPCP wells and extending pump detection period.
A Novel Approach for the Prediction of Real-Time Rate of Penetration in Drilling for Petroleum by Combining the Attention-Based Bidirectional-Long Short-Term Memory and Long Short-Term Memory
Authors: Lyu Z. , Wei F. , Pan Y. , Li L. , Song C. , Song G. , Zhu Z. , Song X. 
Published: February 2025

Abstract
Rate of penetration has been considered as an important factor in the entire drilling industry, which can largely determine the overall costs of drilling a well. This paper proposed a novel real-time prediction of rate of penetration by combining the Attention-based Bidirectional-Long Short-Term Memory and Long Short-Term Memory (Att-Bi-LSTM-LSTM). Eight parameters, which are total vertical depth, weight on bit, revolutions per minute, mud flow rate, density, viscosity, drill-bit outer-diameter, lithology, and rate of penetration, are adopted as datasets. The drilling speed of the well is trained and validated through the drilling data while a sliding window is introduced for the real-time update. In addition, the presented prediction model is compared with other traditional prediction methods. Finally, the prospect of field application and further study is discussed and suggested. The results indicate that the proposed model shows good accuracy and robustness. Moreover, compared with the traditional methods, the model exhibits good superiority with smaller absolute and relative errors. For field applications, the model proposed in this paper attempts to provide a solution to the prediction of real-time rate of penetration. The results are expected to provide guidance for the further study on the increase of drilling speed and reduction of well costs.
Unlocking Hidden Potential: Conventional Log Analysis of Low Resistivity Pay in Gulf of Thailand
Authors: Chokthanyawat S. , Wanwises J. , Chaiwan P. , Junput N. , Thamvittayapoom W. , Thurachen S. , Jiwalai T. 
Published: February 2025

Abstract
Characterizing and evaluating low resistivity pays using conventional log acquisition and the Thomas-Stieber shale distribution method leads to improved hydrocarbon discovery, production, and economic feasibility. This study focuses primarily in the Gulf of Thailand, where results are limited despite the presence of over a hundred wells.
The Thomas-Stieber shale distribution method is a sophisticated approach used in the evaluation of low resistivity pay zones, particularly in fluvial depositional environments like the Gulf of Thailand. This method provides additional information to support the interpretation of conventional logs by accounting for the effects of shale distribution within reservoirs. By applying this technique, geologists, petrophysicists, and petroleum engineers can distinguish between hydrocarbon-bearing formations and those with conductive minerals or shales that may lead to low resistivity readings
From the single sand perforation on low resistivity pay, the effectiveness of this method in the Gulf of Thailand is proven, highlighting its potential to improve the volume of hydrocarbon discovery. This helps operators revisit their idle wells to redevelop existing wells, gain additional production, and potentially reduce the number of new drilled wells, thereby reducing CAPEX/OPEX.
This paper is supported by actual production results from more than three low resistivity pays and confirms the existence of low resistivity pay in the Gulf of Thailand. Operators can better distinguish between hydrocarbon-bearing sands and non-productive zones, leading to more effective production strategies. Accurate characterization of these zones is essential for maximizing hydrocarbon production from both idle wells (non-producing) and newly drilled wells, thereby improving overall field development plans.
Hybrid Velocity Model Building Approach (Wells and Seismic) in Unconventional
Authors: Ghosal Sambit , Nayak Soumya , Cheng Liwei , Pavlov Dmitriy , Wu Xianyun , Johnston Graham , Cruz-konen Heather 
Published: February 2025

Summary
In this paper we demonstrate the methodology to build the velocity model for domain conversion of seismic image data with an aim to maximize value of seismic in unconventional assets. A velocity model is necessary to map depth and thickness of subsurface layers, interpreted from seismic reflection images. Where a seismic reflection image is produced by time or depth imaging, ensures the proper focusing and lateral positioning of the subsurface reflectors. Although a good seismic image is not enough for an exploration or field development. Good well ties and reliable depth conversion are also required (Etris et al, 2002). Time to depth conversion using vertical propagation velocities addresses vertical positioning of the reflectors to true depth. Also, depth conversion is a way to remove the structural ambiguity inherent in time and verify subsurface structure. A depth conversion consists of imaging first, to obtain the best seismic image, then depthing, to tie wells and predict depth away from the wells.
PTTEP Online Ergonomics Checkup
Authors: Amornrat T. , Waraphan N. , Athitaya J. , Jina K. 
Published: February 2025

Work-related musculoskeletal disorders (WMSDs) are a common problem among office workers. WMSDs are caused by excessive work over a period of time. They initially localize and progress over time with aggravating factors including awkward posture, and static or prolonged posture.
The prevalence and incidence of WMSDs was found to be associated with an increase of computer use as most occupations involve compute use. The body structure disorders related to this WMSD include back, neck, and those extremities.
Therefore, PTTEP in conjunction with Medical and Occupational Health Team and The Faculty of Physical Therapy, Mahidol University have established the "Office Ergonomics Checkup and Consultation Project" to identify, assess and give advice for ergonomics in computer users in PTTEP Domestic Assets since 2013. From 2013 to 2019, the project conducted quarterly onsite checkups and consultations at PTTEP Headquarters. Additionally, annual sessions were held at one of the remote operation sites on a rotational basis. Most participants in the project experienced relief from their WMSDs after regularly performing exercises recommended by physical therapists.
Technologies and Achievements for Drilling and Completion of Onshore Deep and Ultra-Deep Wells in China
Authors: Zhang Jiawei , Wang Haige , Ji Guodong , Cui Meng , Chen Lili , Li Wenzhe , Liu Li 
Published: February 2025

Abstract
In the last decade, newly discovered oil and gas reservoirs have gradually shifted from shallow-medium to deep and ultra-deep layers globally. China also has great potential in deep and ultra-deep oil and gas resources, which is identified as the main frontiers due to the increasing difficulty in maintaining economic and sustainable hydrocarbon production from shallow-medium fields after long-term continuous exploitation. The cost-effective E&P of deep and ultra-deep oil and gas resources are crucial for achieving China's energy transition and succession strategy.
This paper reviews numerous challenges encountered during the drilling and completion of deep and ultra-deep wells, including down-hole tool failure due to ultra-high temperature, well control risks from ultra-high pressure, well control or leakage risks due to the narrow pressure window, low ROP due to high strength and abrasive formations, and pipe stuck or wellbore stability problems in salt or mudstone layers. The paper also presents the breakthroughs and applications of high-end equipment, cutting-edge tools and core downhole fluids developed to overcome these challenges, ensuring safe and efficient drilling and completion operations of deep and ultra-deep wells.
With successful breakthroughs and applications of technologies including the 12000m drill rig, wellbore structure optimization, managed-pressure drilling, efficient drill bits, drilling speed-up, ultra-high temperature resistant and high-density drilling fluids, leakage prevention, cementing, ultra-high temperature and pressure resistant oil testing and completion, and ultra-deep coiled tubing equipment, the number of onshore deep and ultra-deep wells in China has been increasing in recent years. Continuous improvements have been achieved in technical performance indicators such as the drilling cycle, ROP and other metrics. Over 200 wells successfully drilled with MD exceeding 8000m have enabled China to normalize 8000m ultra-deep onshore drilling, with drilling capacity reaching 9000m. Moreover, the well depth of TK-1 has successfully exceeded 10000m, making China the second country in the world to successfully drill onshore vertical well with the depth over 10000m. These achievements have well supported the E&P of deep and ultra-deep oil and gas resources in key areas such as the Tarim, Sichuan, Junggar and Qaidam Basins of China.
Additionally, helpful case histories are also provided to illustrate the current status and future directions for research and development of engineering technologies, aiming to achieve a secure and sustainable energy transition while reducing carbon emission through cost-effective E&P of deep and ultra-deep oil and gas resources.
An Accurate Connectivity Identification Method for Complex Shallow Fluvial Offshore Reservoir in Low-Amplitude Structure and its Application in C Oilfield, Bohai Bay Basin
Authors: Li Wenbin , Wang Yichuan , Sun Xijia , Liu Gongli 
Published: February 2025

Abstract
Connectivity is crucial for reserve scale, reservoir understanding and well deployment, which determines reserves and production significantly. However, traditional identification methods always fail in complex shallow fluvial offshore reservoir in low-amplitude structure due to complex wavefield, poor data and fast lateral phase transitions cause by a huge amount of channels cutting and overlapping with each other. Aiming at this problem, we present an accurate identification technology to indicate complex connectivity in these areas more exactly. Firstly, suppress marine noise in several domains. Secondly, establish typical contact modes of channels, whose connectivity are determined based on real data and production performance. Thirdly, seismic response characteristics of typical modes are analyzed based on different series of channel models with changing cutting depth, channel width and sand thickness through forward modeling. Finally, different techniques are used to identify internal single channels and dissect whole areas based on response characteristics respectively, achieving connectivity and remaining-oil areas ultimately better. Results of real data show that our result brings a very good application in promoting efficient development of Oilfield C, which achieves connectivity as well as remaining-oil enrichment areas, ensures successful optimization and implementation of 51 horizontal wells with a 93% oil-layer drilling rate, and provides a powerful tool for characterization of heterogeneity of complex shallow fluvial offshore reservoir in low-amplitude structure.
Geosteering in Laminated Porcellanitic Barmer Hill Formation: a Case Study from Tight Oil Development Reservoir, India
Authors: Walia Neha , Vardhan Harsh , Mokhtar Roslan , Bhuyan Abhinav , Singh Ranjeet , Upadhyay Akriti 
Published: February 2025

Abstract
Deep Azimuthal Resistivity (DAR) geosteering technology enables wells to be steered based on the resistivity observed around the wellbore and in adjacent layers. These types of logging-while-drilling (LWD) measurements provide both petrophysical data and early warning of approaching bed boundaries using geosignals. The geosignal measurement can only be calculated from an azimuthal resistivity tool and it uses raw phase shift and attenuation data, it will horn in the direction of conductivity. A common objective of these applications is typically to enhance production through more precise wellbore positioning, based on accurate characterization of bed boundaries positions and formation resistivity. A 6-1/8″ lateral section was geosteered within BH-6 unit of Barmer-Hill formation. The Barmer Hill reservoir is characterized by tilted fault block structures, with numerous gravity collapse faults. Negotiating this structural complexity, compounded by the presence of multiple hydraulic fracturing operations, posed significant geosteering challenges. BH-6 unit consists of thick high-porosity diatomite lobes intercalated with 1m-thick lacustrine claystone. The geosteering primary objective was to precisely position the well in "sweet zone" of BH6 and maintain the trajectory within this optimal zone and keeping it away from BH-6 intra shale beds. This case study showcases the capabilities of DAR geosteering tools effective well placement and trajectory management within thinly laminated formations.
Full Borehole Image Data Computation Using GAN Based Model
Authors: Liu Y. , Zhou J. , Zhang J. , Li P. , Zhou Y. 
Published: February 2025

Abstract
In logging interpretation, electrical image data is used to identify important geological features such as fissures and cavities, providing crucial information for evaluating productivity. Therefore, obtaining high-quality, fully restored electrical image data is essential for both manual and AI-based image interpretation methods. However, traditional image processing algorithms often produce restored data with poor correlation between geological features across plates, as well as noise and jagged edges. To address this issue, we propose a reliable method for filling in missing sections of electrical image data that can predict high-quality images using deep learning algorithms. While traditional image inpainting algorithms fail to extract meaningful features from pad data, deep learning networks using the encoder-decoder architecture can automatically learn representations of borehole images. In this work, we propose a Generative Adversarial Network (GAN) based inpainting model that generates high-quality missing pad data with semantically meaningful features as a reference for image logging interpretation. We achieved a U-Net based model as an encoder to aggregate contextual information from various feature maps through borehole image data. Based on the encoder, a simple up-sampling decoder with convolution layers is applied to predict the data in the missing area of borehole image data. The pixel-wise discriminator is used to distinguish between real image data and the corresponding synthesized patch. Our proposed model outperforms traditional inpainting methods, achieving an average accuracy of over 89% when inpainting missing areas of real borehole image data, and further validating the superiority of our method through analyzing the image log data with different azimuths. As a result, the encoder in this work also demonstrates its ability to be an efficient backbone model for extracting significant information from borehole image data.
Extending Saturation Water Calculation in 3D Reservoir Space Using Stochastic Approach
Authors: Manuaba Ida Bagus Gede Hermawan , Santoso Gagok Imam , Wibisono Dermawan , Marhaendrajana Taufan 
Published: February 2025

Abstract
Updating the reservoir model post-production involves integrating new data and describing for changes in resistivity and water saturation over time. This paper explains into extending the calculation beyond the wellbore, using a stochastic approach to navigate these challenges and enhance accuracy in reservoir characterization.
The Archie Equation is frequently used to assess resistivity and saturation. However, due to measurement uncertainties, a single deterministic value isn't sufficient. By adding stochastic methods in Archie Equation, we integrate diverse data inputs from various sources to enhance calculation and tackle uncertainty more effectively. The example was applied in a carbonate reservoir with some water corridors, and the computational approach extended in a radius of 200 feet within a 3D volume using LWD 3D reservoir mapping technology. By extending the analysis beyond traditional boundaries, we aim to provide a more holistic understanding of reservoir dynamics and improve decision-making in oil and gas production operations.
The well was drilled to a depth of approximately 4,000 feet measured depth (MD) within the reservoir section, utilizing comprehensive petrophysical analysis to assess textural properties and reservoir characteristics vital for optimizing completion strategies. Using the 3D Resistivity Volume from UDAR tool, water saturation levels within a 200-foot radius were calculated and correlated with interpretations near the borehole. However, due to the extensive nature of these calculations, the analysis was limited to a 100-foot radius. This example focused solely on the stochastic approach to demonstrate its robustness in accurately delineating fluid distribution within the 3D spatial domain.