bluuebunny/crossref_metadata_2025_split huggingface dataset:
The invention relates to a method for simulating phase permeability curve based on conventional logging data
Authors: Fu Yan , Xia Lian-jing , Shuo HU , Dong Li-jun , Ying DU , Cao Teng-fei , Zhang Li-li , Dai Ming-duo , Li Yi-xiao 
Published: November 2024

Abstract
Phase permeability curve is the curve of relative permeability (effective permeability/oil phase permeability in bound water) and water saturation change obtained through core phase permeability experiment. It is an indispensable data in oilfield development calculation, dynamic analysis, determination of oil-water saturation distribution in reservoirs and other water-driven oil related calculations, and an important index for reservoir evaluation. The study of effective permeability and relative permeability is of great significance for controlling the uniform advance of oil-water or oil-gas boundary and rationally developing oil and gas fields. The only effective way to study the phase infiltration is the core phase infiltration experiment, but the number of lithology samples is very limited, so the phase infiltration in oilfield development and application is still in the estimation stage, the accuracy is low, and the practical application is not strong. In order to improve the applicability of the phase permeability curve, it is necessary to establish a set of electrical interpretation methods associated with logging curves to realize electrical simulation instead of core measurement. In this paper, an electrical interpretation model of oil-water phase permeability is established based on flowable porosity and pore radius, and the effective seepage dynamic prediction and inversion of oil-water phase in each development stage of each reservoir is realized, which lays a solid foundation for the fine development of the reservoir.
Discussion on the Technology of Leak Prevention and Sealing in Drilling Engineering
Authors: Pengwei Li , Dajun Ru , Jianning Wang , Longfei Yin , Zhang Bo , Yongsheng Ye , Ligong Yang , Kang Yang 
Published: November 2024

Abstract
Lost circulation is one of the most serious and complex situations that affect the safety of drilling operations. The occurrence of lost circulation not only causes losses to drilling engineering, but also poses great difficulties for the exploration and development of oil and gas resources. Only by solving the problem of well leakage can drilling operations be carried out effectively and economically. Lost circulation can have a significant impact on exploration and development work. However, everything has two aspects. In the case of the same reservoir and leakage, once a well leakage is found, it indicates the appearance of an oil and gas reservoir, which is more common in fractured reservoirs. Therefore, in the expected drilling of reservoir sections, it is necessary to analyze and judge leaks well to avoid human error. Leakage can occur in shallow, medium, and deep layers, as well as in different geological epochs, such as from the Quaternary to the Paleozoic, and can occur in various rock formations. From the perspective of drilling, with long open holes, multiple pressure layers, and complex formations, especially when drilling adjustment wells, the problem of well leakage appears to be common and more serious, and the occurrence of well leakage will cause significant economic losses. So, we should prioritize prevention and try to avoid the occurrence of well leakage. If drilling is carried out in formations with well leakage, but appropriate drilling techniques and measures are taken, it is possible that well leakage will not occur, and at least the degree of leakage can be greatly reduced. In case of a well leakage, effective measures should be taken in a timely manner to block it and ensure the smooth progress of drilling. Therefore, the significance of researching leak prevention and plugging technology is significant.
Optimization of Rock Breaking Parameters by Combing Mechanical Specific Energy Theory and Random Forest Algorithm
Authors: Mu Hua-yan , Jiang Guan-cheng , Sun Jin-sheng , Dong Teng-fei , He Yin-bo 
Published: November 2024

Abstract
As the key indicators to evaluate drilling efficiency, mechanical rate of penetration (ROP) and mechanical specific energy (MSE) are affected by many uncertain factors. In the actual drilling process, it is often necessary to adjust the parameters to achieve speed and efficiency. A dual-objective model is established considering the maximization of ROP and the minimization of MSE. Which combined with the theory of mechanical specific energy and the principle of multi-objective optimization, the model parameter weights are determined by the feature importance in the random forest regression model, and the value range of rock breaking parameter is optimized, realize the fusion of physical model and data model. The results show that, in the four strata of well X, the average ROP of T2k1 stratum is increased by 48.6% and the average MSE is decreased by 26.6%, the average ROP of T1b3 stratum is increased by 89.9% and the average MSE is decreased by 33.8%, the average ROP of the T1b2 stratum was increased by 41.3% and the average MSE was decreased by 39.0%, the average ROP of the T1b1 stratum was increased by 29.2% and the average MSE was decreased by 37.3%, which met the dual objectives of maximizing the ROP and minimizing the MSE. Compared with the traditional single-objective optimization method, the established dual-objective model is more in line with the needs of complex drilling engineering, and the fusion of physical model and data model can reduce certain human error.
Research and Application of Plugging Drilling and Completion Technology for Difficult Old Well in Changchun Gas Storage
Authors: Qing Chuan , Zhang Xiaohui , Liu Changdong , Liu Qiang , Gong Hongzhe 
Published: November 2024

Abstract
Changchun Gas Storage has been included in the 14th Five-Year Plan for the development of petroleum and natural gas in Jilin Province. Its smooth construction and safe operation are crucial to ensure the stable supply of natural gas in Changchun. Well X106F located in the construction area was abandoned in 1988 due to drilling tool falling and multiple salvage failures. In order to ensure the sealing and integrity of the gas storage, it is necessary to effectively plug the drilling cover. In view of the problems of low well history accuracy, poor well wall stability and difficulty in cementing large boreholes, open hole drilling, trajectory design and control, film-forming and wall-fixing drilling fluid and prestressed cementing technologies are applied. By optimizing drilling tools, optimizing drilling parameters, designing the three-opening well structure and “five-section” profile, the plugging well construction requirements are met. The first and second open drilling along the old well borehole, 1313m deep on the first try to find top of the fish, after cementing plug, side tracking to 50m below the top of the fish and then cementing;for third spud control trajectory to accompanied the old well, according to the results of passive magnetic guidance, real-time adjustment of the trajectory scheme and construction plan, finally successfully collided with the old well at 1893m deep, after cementing the drilling plug, perforating and extruding cement, the cement job quality is good. The whole well construction period of 100 days, creating the fastest record of the old well plugging without trajectory of the fish type, providing technical support for the construction of Changchun gas storage, and providing experience for the same type of old well plugging and complex well treatment in China.
Application of Reservoir Blockage-relieving in Low Permeability Carbonate of Jingbian Gas-field
Authors: Hou Yi , Li Hao , Liu Ruchao , Zhang Peng , Zhang Anna Rui 
Published: November 2024

Abstract
Jingbian gas-field is a low-permeability and lithological gas reservoir with strong reservoir heterogeneity and poorly physical properties. As the gas-field is getting older and older, its gas wells start to produce less, and have growing difficulties to lift water and finally fail to work normally and steadily. One inborn factor lies in the unstable liquid composition of Jingbian gas-field: salty formation water with easy-fouling ions and acidic gas such as CO2 and H2S. Living in the underground for a long time these active materials prone to make the forming of water blocking and the solid deposition, which will weaken gas flow ability and threaten the production. After a detailed study on the plugging, there are three kinds of blocking divided: abruptly impurity blocking, slowly water locking, and energy deficiency. To relieve these blocking, methods have been put forth and carried out in field with achievement. The successful application has brought blockage gas wells solutions in Jingbian gas-field.
Study on Variability Production Characteristics of Fracturing Fluid Imbibition Displacement for Typical Shale
Authors: Zhu Xiu-Lan , Li Teng , Peng Xiang , Yang Zhen , Wang Qi-Xuan , Zhang Qing-Jiu 
Published: November 2024

Abstract
CO2 injection is a prominent measurement to enhance the recovery of shale reservoirs. The imbibition of fracturing fluid + CO2 additive is considered important for promoting the enhancement and stabilization of shale oil production to ensure energy supply. The imbibition experiments of fracturing fluid + CO2 additive were carried out in shale reservoirs with a nuclear magnetic resonance (NMR) test. The imbibition displacement characteristics at different pore scales of shale were quantitatively evaluated. The variability of the imbibition effects in shale reservoirs was clarified in terms of shale type, fracturing fluid type, and CO2 additive (pressure). This finding indicates that the effectiveness of the fracturing fluid + CO2 additive imbibition on shale reservoirs is stronger, and the imbibition displacement efficiency ranges from 33.38 % to 41.56 %. The imbibition contribution rate is considerably higher for small pores than for large pores, and the difference between them is more than 10%. Therefore, the imbibition of fracturing fluid + CO2 additive mainly extracted crude oil from the small pores of shale reservoirs. CNI nano variable-viscous slippery water is more effective for imbibition displacement in laminar type shale. For laminated type shale, EM30+ + guanidine gum mixed water has a better imbibition effect than CNI nano variable-viscous slippery water. Under 16 MPa CO2 + fracturing fluid (miscible states), the imbibition displacement efficiency of the shale is significantly enhanced. The imbibition displacement degree at different pore scales is also increased. For different types of shale reservoirs, the imbibition displacement degree at different pore scales would be improved by methods, including the optimization of the fracturing fluid or the change of imbibition conditions. This study presents a theoretical underpinning for the high-efficiency exploitation in shale reservoirs.
Feasibility Study on Infiltration of Sidetracking Horizontal Wells in Fuyu Tight Oil Field
Authors: Zheng Siqi 
Published: November 2024

Abstract
The Fuyu oil layer in well area 1 is a tight reservoir. Due to poor reservoir properties, conventional fracturing production wells have low production and rapid decline, with a recovery rate of only 2.22%.. Moreover, the surface of the well area is a wetland protection zone along the river. Under the new safety and environmental protection policies, new drilling is not allowed in the protection zone. In order to improve the development effect of the well area and increase the recovery rate, based on the geological and development characteristics of the oil reservoir, and in response to the problem of fast water breakthrough in east-west oil wells and ineffective water injection in non east-west oil wells in the Fuyu oil layer, the main oil layer with high well control degree, small well network density, and well-developed reservoir is selected. The original development well points are used to sidedrill stepped horizontal wells, combined with volume fracturing of tight oil horizontal wells, to avoid adjacent reserve losses, Exploring a new infill model for sidetracking horizontal wells in tight oil reservoirs in Fuyu, providing reference for effective development of similar reservoirs.
Design Method and Reliability Analysis of Deep Well Casing Strength
Authors: Yaxuan Wang , Jiayu He , Hongzhi Xue , Zhiyong Wei , Wang Lin , Weixing Zhu 
Published: November 2024

Abstract
With the development of the petroleum industry, more and more oil fields are beginning to engage in deep well exploration. Deep well casing is an important drilling equipment in oilfield development, which is a key factor in ensuring wellbore stability, maintaining production safety, and improving production capacity. However, due to the high requirements for equipment in drilling operations, problems in the design, manufacturing, and installation of deep well casing can easily lead to issues such as poor wellbore stability, oil leakage, and drilling accident safety. Therefore, the performance and reliability evaluation of deep well casing has become a key issue. This article summarizes the research progress of deep well casing strength design methods and reliability analysis through extensive research on existing literature. The main content includes the working principle, design standards, and advantages and disadvantages of different methods of deep well casing, aiming to provide reference for the design and use of deep well casing.
Experimental study on acidizing of natural gas hydrate reservoirs
Authors: Liu Pingli , Huang Qisheng , Du Juan , Shu Hui , Wang Ming 
Published: November 2024

Abstract
Natural gas hydrates (NGH) are a promising resource. Due to the weak cementation of hydrate reservoirs, the reservoirs are prone to sand production or destabilization during hydrate dissociation. Samples of hydrate sediments were manually prepared, consolidated using a cementing agent, and then subjected to flow experiments using an acid solution. Comparative experiments were also conducted with unconsolidated samples. The consolidation samples could maintain the skeleton morphology after acidizing, and no sand production was observed; the unconsolidated samples had severe skeleton deformation after acidizing and serious sand production. The permeability of the consolidation samples after acidizing was 2.95mD, and porosity increased by 8.56%; the permeability of the unconsolidated samples after acidizing was 1.26mD, and the porosity decreased by 7.45%. CT scan images and mercury intrusion curves show good pore development after acidizing the consolidation samples, while the unconsolidated samples have poor pore development and sand plugging after acidizing. This result is because the cementing agent can consolidate the sand and gravel so that it will not be dislodged and transported during the acidizing process, thus maintaining reservoir stability. This study demonstrates the feasibility of acid modification technology in hydrate reservoirs, which is informative for the safe development of gas hydrates.
A Deep Learning Structure Correction Method Under the Influence of Special Lithology Body
Authors: Jun Zhu , Yonglei Liu , Ning Yin , Jiawei Ren , Xiaochuan Yang , Wei Luo 
Published: November 2024

Abstract
In the process of precise exploration and development of oil and gas reservoirs, the accurate implementation of the target layer structure plays a vital role in the increase of oil reserves and the success of drilling. However, with the gradual deepening of the research, it is found that in the overlying strata of oil and gas reservoirs, special lithological bodies with strong heterogeneity and abnormal velocity are usually locally developed, which directly affects the construction of seismic data migration velocity, resulting in structural distortion at the local position of the reservoir in the process of data interpretation. Focusing on the structural change caused by the abnormal velocity, the deep learning algorithm is used to accurately predict the velocity of the special lithologic body and realize the accurate correction of the structure. Firstly, based on the combination of seismic and geological understanding, the geological model of the target layer and the overlying special lithologic body is constructed, and the distribution law of the special lithologic body is identified by the forward simulation method. Then use the well-side seismic trace and P-wave velocity curve to train the velocity data through the deep learning method and apply the training results to the post-stack seismic data to obtain the accurate P-wave velocity body. Finally, the real formation velocity over the target layer is restored to achieve reservoir structure correction. Based on this method, the research experiment was carried out in the M block of the Tarim Basin, and the spatial distribution range of the special lithology body was carved. The data error between the migration velocity body and the abnormal high-velocity body was calculated, and the target layer structure in the study area was corrected.
Application of Simul-frac technology in Longdong shale oil field
Authors: Che Haoyang , Bai Mingwei , Chai Long , Zuo Ting , Li Zefeng 
Published: November 2024

Abstract
This paper for the transformation of unconventional reservoir large-scale volume fracturing of long operation cycle, equipment occupancy, through the well optimization, fracturing design optimization, supporting equipment, construction organization mode upgrade, in the changqing oilfield longdong shale oil HX platform realized a single set of fracturing vehicle for two well synchronous shunt fracturing, created a single unit 17 hours fracturing 10 shale oil reservoir transformation new record. Compared with the production mode of two sets of fracturing units on the same platform, the efficiency of synchronous shunt fracturing operation of single unit increased by 32.1% and the number of equipment used decreased by 17.3%, which initially reflected the advantages of synchronous shunt fracturing technology in improving quality and efficiency. Through the output tracking analysis of the horizontal Wells of synchronous shunt fracturing transformation for half a year, the four Wells showed good transformation effect. Synchronous shunt fracturing technology in changqing oilfield shale oil platform successful application for the future unconventional oil and gas resources cluster well fracturing transformation speed to provide new ideas, the technology can improve the efficiency of oil service enterprises, reduce the completion cycle and comprehensive operation cost, for oilfield company, can quickly build production effect.
Difference of Sedimentary Characteristics and Main Controlling Factors Between Platform Margin Shoal and Ramp Shoal in M Formation of A Oilfield in The Middle East
Authors: Yu Yi-Chang , Shen Yi , Jing Xi , Xu Ya-Nan , Wang Yi-Fan , Guo Rui , Li Feng-Feng , Wang Jiu-Zhou 
Published: November 2024

Abstract
The bioclastic limestone reservoirs of M Formation in A Oilfield mainly develop in the ramp shoal and platform margin shoal, but the sedimentary characteristics, spatial distribution and main controlling factors of the two types of shoals are significantly different. Based on the data of seismic, well logging, core, casting thin sections and analytical tests, the comparative analyses of lithology, petrophysics and spatial distribution of the two types of shoals are carried out, and the control mechanism of relative sea level rise and fall and paleogeomorphology on their development is clarified. It is showed that the two types of shoals can be subdivided according to hydrodynamic conditions and bioclastic types. The platform margin shoals are dominated by grainstone and gravel limestone, and the bioclastics are mainly rudist and echinoderms. The logging curve is funnel-shaped, and the seismic is patchy distribution. In the vertical direction, the grain size of shoals becomes coarser, and the sedimentary sequence of medium energy shoal—medium-high energy shoal—high energy shoal is developed. In the horizontal direction, the facies belts of different shoals are narrow, and they are distributed quasi-layered semi-continuously around high energy shoals. The ramp shoals are dominated by packstone and grainstone, and the bioclastics are mainly non-fixed bivalves and algae. The logging curve is micro-tooth box-shaped, and the seismic is sheet distribution. In the vertical direction, the grain size change of shoals is not significant, and the sedimentary sequence of medium energy shoal—medium-high energy shoal is developed. In the horizontal direction, the facies belts of different shoals are wide, and they are distributed layered continuously around medium-high energy shoals. Relative sea level change controls the energy of sedimentary environment and the type of shoal facies, and the high position of paleogeomorphology controls the formation and distribution of high energy shoals. When the relative sea level is high and the paleogeomorphology is gentle, the ramp shoal is developed. As the relative sea level drops, the hydrodynamic condition increases, and the difference in the accumulation speed of different shoals enhances the fluctuation of the paleogeomorphology, the ramp shoal gradually transitions to the platform margin shoal. The above research can provide reference for the exploration and development of such reservoirs.
Study on the modularization of project operations under the “oil company” model
Authors: Hu Yue , Dai Cheng , Zhang Hao 
Published: November 2024

Abstract
A rational and efficient business management and operation model is a prerequisite for the smooth operation of an organization. This study aims to build an intensive and efficient business management model with the characteristics of the “oil company” model. Compared with the traditional business management model, the “oil company” model has significant advantages in terms of organizational structure, communication efficiency, work style and work efficiency, etc. Due to the compression of management levels and the shortening of business chains, the communication efficiency and work efficiency are higher, and the composition of personnel and work style are more flexible. Therefore, based on the theory of the “oil company” and on the idea of compressing management levels and shortening management chains, business management departments should be integrated, streamlined and optimized, and business chains should be sorted out.