bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the Optimization of the Integrated Process Parameters of Fracturing and Flooding in Beach Bar Sand Reservoir
Authors: Ma L. , Lu C. , Guo J. C. , Wang Y. C. , Jiang Z. X. , Chen B. G. , Zhou Y. L. , Yuan H. R. , Tang Z. B. , Sun P. X. , Wen X. L. , Qi D. , Huang W. H. , Ding H. X. , Diao D. X. , Wang M. , Xu J. B. 
Published: September 2023

ABSTRACT
The beach bar sand reservoir has the characteristics of low porosity and permeability, multiple thin layers and strong vertical heterogeneity. In recent years, the integrated technology of fracturing and flooding has been put forward. Based on the geological model of injection-production well group, optimization of water injection parameters of fracturing-flooding and the optimization of production well fracture parameters under the condition of fracturing and flooding are carried out in the stimulation of beach bar sand reservoirs. The research results show that optimizing the water injection volume of fracturing-flooding based on numerical simulation is 50000∼100000 m3, and the water injection rate of fracturing-flooding is 0.7∼0.9 m3/min, which can reduce the risk of production well water channeling and achieve the goal of balanced water injection. Then, the front edge of water injection in fracturing-flooding is determined by analyzing the sweep area of fracturing water injection. Based on the well spacing and ultimate flow distance of low permeability reservoirs, the half length of fractures in different types of production wells was optimized. The research results can effectively guide the economic and efficient development of beach bar sand reservoirs under the condition of fracturing-flooding and water injection.

INTRODUCTION
Bin435 block of Shengli Oilfield is located in Binzhou City, Shandong Province. It is structurally located in the west slope of Lijin depression. Oil layers are drilled in the upper S4 sub-member of Shahejie Formation. The area of the work area is 1.23 km2 and the crude oil reserves are 208 × 104 t. The upper sub-member of the target layer of Shahejie Formation consists of 1∼4 sand formations, with a buried depth of about 2700∼2900 m. It is a beach bar sand deposit with sand and mud interbedding. The sandstone is mostly gray or light gray siltstone, argillaceous siltstone and calcareous siltstone. The mudstone is gray or sandy and mainly gray. The overall structural feature is a monoclinic structure complicated by the fault layer. The average porosity of the reservoir in this block is 14.6%, and the average permeability is 6.2 × 10−3 D. There are many small oil-bearing layers with a longitudinal span of 150 m, the average thickness of the sand body is small, the single-layer protrusion coefficient is large, and the vertical and horizontal heterogeneity is strong. It belongs to the typical low porosity and low permeability beach bar sand reservoir (Shao, 2012).
Digitalization in Mining Geomechanics – Looking to the Future
Authors: Mitra R. 
Published: September 2023

ABSTRACT
According to Deloitte (2014), the term "Industry 4.0" refers to the next development stage in the organization of the entire value chain process in the manufacturing industry. The mining industry, just as any other industry, is also in the process of moving into this new stage. The challenges facing the mining industry are increasing, with environmental concerns becoming broadly understood, emergent technology changing the nature of work and society and resource nationalism fueling the expectations of a better life. New and emergent technology and working practices, increased stakeholder expectations around competitive economic returns and rents, and community expectations for an inclusive and sociably acceptable industry is leading to changes in the roles and attributes of the mining engineer of the future (Smith 2017). Similar to other areas within the mining industry, there is a lot of digitalization being implemented in the field of mining geomechanics. This paper will review some of those technologies that have been developed in the field of mining geomechanics along with looking into some future opportunities.

INTRODUCTION
According to Deloitte (2014), "Industry 4.0" refers to the next development stage in the organization of the entire value chain process in the manufacturing industry. The first industrial revolution was observed in the late 18th century with the arrival of steam power and the invention of the power loom. This led to mechanization and radically changed how goods were manufactured. The late 19th century saw the second industrial revolution when electricity and assembly lines made mass production possible. In the beginning of the 1970s, the third industrial revolution was observed. During this time, advances in computing enabled the programming of machines and networks, powering automation (Deloitte 2018). An overview of the evolution of these industrial revolutions can be seen in Figure 1.
According to Marr (2016), Industry 4.0 introduces what has been called the "smart factory". In this system, the cyber-physical systems monitor the physical processes in the factory and make decentralized decisions. The physical systems become an Internet of Things (IoT), communicating and cooperating both with each other and with humans in real time via the wireless web. The development of Industry 4.0 will be accompanied by changing tasks and demands for the people in the factory (Gorecky et al., 2014).
Effect of Binding Material on the Acoustic, Elastic and Strength Properties of Artificial Granular Rocks
Authors: Pothana Prasad , Gokapai Vasanth , Ifrene Ghoulem , Ling Kegang 
Published: September 2023

ABSTRACT
Artificial sandstone-like rocks fabricated in the laboratory offer great advantages in controlling their grain size distribution, grain morphology, porosity, and cement content. Synthetic granular rocks offer an efficient way to validate existing analytical models, calibrate numerical models, and perform sensitivity analyses on specific physical parameters. Synthetic sand-stone rocks are manufactured by gluing grains together with a binding material. In this study, we investigated the effect of the three binding materials typically used in synthetic granular rock preparation on mechanical properties and acoustic wave velocities. We used ceramic spherical particles with sizes of 250 μm − 425 μm as grains bonded together by three binding materials, namely i) Epoxy resin, ii) Sodium Silicate with Kaolinite, and iii) Portland cement. While fabricating the core plugs, in each case we kept the relative volume proportion of the binding material with respect to the grains constant. These manufactured sandstone-like dry core plugs were then tested using Autolab-1500 triaxial testing equipment to measure the static mechanical properties and elastic wave velocities at a fixed confining pressure and temperature. Although grain size and distribution, confining pressure, etc., affect the mechanical behavior of rocks, our study focuses on the influence of the binding material alone. Despite the volume fraction of each binding material being the same, they influence the mechanical properties of the rock differently. The sample prepared with epoxy resin exhibited the highest values for Young's modulus, Poisson's ratio, and unconfined compressive strength (UCS) among the three samples. Our findings demonstrate that the selection of binding material plays an important role in controlling the mechanical properties of the rock. Two main reasons account for this behavior: i) the heterogeneous distribution of the binding material within the rock specimen and ii) the effect of the binding material itself on the contact behavior between the grains.

INTRODUCTION
Thermal-Hydro-Mechanical (THM) coupling processes are essential to various engineering and geoscience problems, such as geothermal energy extraction, geological storage of CO2, and nuclear waste disposal. Understanding the interplay between these processes is crucial for predicting the behavior of the Earth's subsurface systems. However, the natural heterogeneity, inhomogeneity, and non-uniformity of geological materials make these processes inherently complex and difficult to model accurately (Tsang, 1991; Rutqvist and Tsang, 2005). To address this challenge, numerical modeling has become a popular tool for simulating THM processes. Nevertheless, robust calibration of numerical models remains a significant obstacle due to the natural variability of rocks (Yoon, 2007).
Optimization and Evaluation of a Novel Stabilizer Applied to the Strong Water-Sensitive Conglomerate Reservoir
Authors: Zhang Kun , Yao Er-dong 
Published: September 2023

ABSTRACT
Mahu Oilfield is the world's largest conglomerate oil field with 1.24 billion tons of petroleum reserves discovered so far. It is mainly a tight conglomerate reservoir with low porosity and low permeability. In the early stage of field development, it usually has characteristics of high flowback rate and low oil production rate. This may be attributed to strong water-rock interactions during hydraulic fracture operation. When water-sensitive minerals in rocks encounter water, clay expansion and particle migration occur, resulting in reduction of rock strength and fracture collapse. In order to choose a suitable anti-swelling agent for Mahu Oilfield, XRD, zeta potential, anti-swelling rate, immersion, Brazil splitting and other test means are used. Then, we evaluated the performances of inorganic salts and inorganic cationic polymers on clay swelling control and rock stability, and their combination and optimal ratio were also studied. The experimental results show that the clay content of the rock is up to 37.3%, of which 88% is the expandable montmorillonite mineral. The mixture of inorganic salt and inorganic cationic polymer can effectively inhibit the water-rock reaction by reducing the clay expansion and compressing the double electric layer on the rock surface. Through the test of swelling rate, it is found that the swelling rate of optimal reagent for montmorillonite can reach 92%, and the swelling rate of the reservoir rock powder can reach over 70%. The results of the rock immersion experiments show that the optimal stabilizer can ensure the strong water-sensitive conglomerate remains stable after soaking for 24h without dispersion. Compared with the KCl solution commonly used in oilfields, it can increase rock strength by more than 10% without increasing cost. The results of this study provide a solution for hydraulic fracturing in highly water-sensitive reservoirs.

INTRODUCTION
Mahu Oilfield is the world's largest conglomerate oil field with 1.24 billion tons of petroleum reserves discovered so far (Li et al., 2020). However, the reservoir is rich in water-sensitive minerals such as montmorillonite (Uddin, 2008). To effectively develop such tight reservoirs, hydraulic fracturing is commonly used (Li et al., 2015). Water injected during hydraulic fracturing interacts with reservoir rock, resulting in a decrease in fracture conductivity and well productivity (Ferguson et al., 2013).
Observation of Brazilian Tensile Failure of Rock Simulant by Digital Image Correlation Method
Authors: Tanaka S. , Nakashima S. 
Published: September 2023

ABSTRACT
The purpose of this study was to investigate the applicability of the digital image correlation method, which uses image processing to obtain areal strain distributions, for the observation of rock fractures. In the results of the Brazilian tensile test, the strain increase process just prior to crack initiation was captured when the images were taken at 8,000 fps. The tensile testing of a rubber sheet coated with irregular spots confirmed that the accuracy of the analysis was sufficient, indicating that digital image correlation can be applied for the observation of crack propagation in rocks. By simulating the Brazilian tensile test with a manual mechanical jack, the experiment was conducted on gypsum specimens, and high-resolution images of the experiment were taken. The results of the analysis showed that the cracks started at the points of increased strain by comparing the normal strain distribution in the X direction and the shear strain distribution with the actual crack locations.

INTRODUCTION
It is important to evaluate the initiation and propagation of cracks in a rock mass during the cavity excavation. In the case of hard rock, the fracture initiation occurs in a short time, making it difficult to observe the process. However, recent advances in digital imaging devices have made it possible to capture high-speed, high-resolution images of rock fracture experiments. If the strain distribution in an area can be measured by image processing, it will be possible to track the initiation and progress of the fracture.
Strain gauges have usually been used to measure the strain generated in structures. However, the strain value obtained from a strain gauge is the average strain at one point in one direction; and thus, many strain gauges need to be installed for multipoint measuring. This involves complicated wiring to the measurement device, which causes problems in terms of labor and cost. In addition, as cracks develop or crack widths increase, the strain gauges may break off, making measurement impossible. On the other hand, digital image correlation can obtain the strain distribution over a wider range than strain gauges. It is a simple method requiring only the image of the object to be captured. Digital image correlation (DIC) can measure complex cracks and large deformations. DIC uses a camera to capture the speckle pattern (irregular dots) on a sample surface and measures the displacement and strain distribution from the correlation of images before and after deformation.
Mechanics of Tunnel Intersections: Closed-Form Approximations for Deformation Modeling and Failure Prediction
Authors: Michael Andreas , Gutierrez Marte 
Published: September 2023

ABSTRACT
This study aims at improving our understanding on the stress field dominating the intersection between two tunnels of different diameter and hence provide insights on the stability against shear failures in this vicinity. Theoretical modeling of the deformation of rocks at the intersection point of two tunnels leads to prediction of possible localized shear instabilities. The general state of stress underground is that in which three principal compressive stresses acting in mutually-orthogonal directions. Subsurface stress analysis methods established in geomechanics have been applied to underground tunnels. Modifications have been necessary for the vicinity around the tunnel intersection because of stress interferences coming from each tunnel, accomplished using an analytical-approximation technique established in petroleum engineering for modeling the intersections of a well with its perforation tunnels. The orthogonal intersection between a "Tunnel A" and a smaller "Tunnel B" is considered and closed-form expressions are derived for evaluating the deformation in the vicinity as a function of the in-situ stresses and assess occurrence of shear failure induced by the application of these compressive stress loads using the Mohr-Coulomb failure criterion. Non-orthogonal intersections are also discussed. The validity of the derived closed-form approximations can be further investigated through numerical modeling, and laboratory or field-scale experimentation.

INTRODUCTION
The thrust of this paper is the improvement of our understanding on the stress field dominating the intersection between two underground tunnels, along with insights on the stability against shear failures (induced by compression), in this vicinity. This objective is achieved by analytically-approximating the behavior (stress-displacement relations) of the rock in the intersection plane between two cylindrical or elliptical excavations of different sizes ("Tunnel A" intersected orthogonally in its side by a smaller "Tunnel B"). Subsequently, closed-form approximations can be derived for deformation modeling and shear failure prediction considering the Mohr-Coulomb failure criterion.
Investigating the Impacts of Porosity on the Rock Mechanical Properties of Sandstone
Authors: Emad M. Z. , Waqas M. , Khan M. U. 
Published: September 2023

ABSTRACT
Laboratory testing of rocks and developing their interrelationships is a good way for assessment of rock behavior for mining and construction industries. A detailed testing program was envisaged to establish possible correlations between porosity and mechanical properties of sedimentary rocks from Salt range Punjab, Pakistan. Sandstone samples were collected from different formations of the salt range area. Sample preparation was carried out at the rock mechanics laboratory at UET Lahore as per suggested methods of ISRM. Samples with partings or defects were removed from the testing program. Acceptable samples were tested for porosity, density, UCS, BTS, and other properties. The test results obtained were used for statistical analysis to find possible correlations using MS Excel. The analysis showed that the rocks can be divided into two groups. The predictive relationships were determined between porosity and static mechanical properties of rocks, and between porosity and dynamic mechanical properties.

INTRODUCTION
Determination of geotechnical data for any engineering project is a key aspect of design and research. Laboratory investigation of rock involves carefully testing of rock samples after preparation in accordance with the ISRM or ASTM standards. Some examples of useful rock properties include but are not limited to uniaxial compressive strength (UCS), Young's modulus, Poisson's ratio, tensile strength, and sonic wave velocities through rocks. Some non-destructive tests like sonic velocity (P and S waves), porosity (η), and density (ρ) can be performed on same sample before the destructive tests like Youngs modulus (E), Poisson's ratio (υ), compressive and tensile strength (σt). Non-destructive tests are very popular in rock engineering as these are cheaper than the destructive tests and require almost no sample preparation. Rock mechanical tests are also used for geotechnical investigation for a project in rocky areas. The most important factors that affect the sonic velocity in rocks are type of rock, mineral arrangement, density, porosity, anisotropy, pore-water, confining pressure, temperature, weathering, texture, structure, grain size, and grain shape. Generally, the rock behavior under stress is governed by the factors like interlocking between grains, grain size, texture, composition, pores, arrangement of minerals and pores, and external factors like weathering, groundwater, nature of applied stress, etc. Rock mechanic professionals and researchers have produced good literature to determine and explain rock behavior through correlations (D’Andrea. 1965; Chang et al. 2006; Chary et al., 2006; Hashemi et al., 2010; Kahraman and Yeken, 2008; Khandelwal and Singh, 2011; Norouzi et al., 2013; Sabatakakis et al., 2008; Shalabi et al., 2007).
Rock Salt Block Extraction Using Conventional Rock Mining Methods
Authors: Emad M. Z. , Majeed Y. , Waqas M. , Rehman G. 
Published: September 2023

ABSTRACT
Rock salt is produced in large quantities in Pakistan's Salt Range region. Salt tiles, blocks, and lamps are the primary rock salt exports, whilst household usage and the chemical sector are the main local consumers. The size, shape and quality of the block play a role in how profitably salt may be produced for value addition. When the blocks have very few cracks, adding value to the salt is simpler. The current method of extracting salt includes drilling and blasting that causes unintended cracks in the blocks. The extraction of rock salt blocks using traditional cuboid-shaped block mining techniques is the main topic of this research. The methods include blasting with low-yield explosives, expansion agents, and wedges and feathers. The in-situ experiments resulted in wedges and feathers approach being the most effective way to mine rock salt blocks of the correct size and form, while reducing cracking. Using core drilling at the block's edge, the quality of the blocks for the various procedures was evaluated.

INTRODUCTION
Rock salt is mined using traditional drill and blast methods in both underground mining and quarrying operations. In general, automated mining processes make it possible to recover minerals using mechanical excavators, brine pumping, and evaporation techniques. Nonetheless, the room-and-pillar method of conventional underground mining of large deposits is the most time-tested and widely used method for extracting salt. The salt recovery is about 40%, rest is left in the mine to support the roof (Hustrulid, 2001).
With an annual production of roughly 2.16 Mt, Pakistan is a country that produces rock salt (Department of Mines & Minerals, 2015). Just 15% of salt produced is thought to be export quality, with the remaining salt being of low value because of cracks created during mining. Globally, Himalayan rock salt is a very well-liked product. There is high demand for a variety of products, including salt blocks, salt lamps, tiles, salt block slabs, and materials for medical slabs (Naz and Haleem, 2010; Rashleigh et al., 2014).
Numerical Modeling of Deep Borehole Heat Exchanger in Southern California - Feasibility Study
Authors: Chen Haohua , Tomac Ingrid 
Published: September 2023

ABSTRACT
This paper presents an investigation into the feasibility of low thermal-gradient deep Borehole Heat Exchanger (BHE) applications on campus at the University of California San Diego (UCSD). With a review of primary source data for various formations and well logs around the UCSD campus, the stratigraphy and thermo-physical properties of the formation were evaluated. Based on the collected information, a numerical model for the BHE application was developed. Circulation of water through a closed coaxial loop system considers the variation of several parameters in order to develop the feasibility study and obtain guidelines for the future UCSD geothermal resource. For example, multiple layers of the formation and thus the variance of ground thermal conductivities along the vertical direction were considered, and fluid velocity and borehole depth were varied. To do that, a numerical scheme that employs finite element schemes for modeling Navier-Stokes fluid flow and heat flow and transport in the BHE system constructed the numerical model. The numerical model verification was first performed via comparisons with a field test on BHE from the literature. Then the effects of the thermal properties, volumetric flow rate, and other relevant parameters were systematically analyzed by using the developed numerical modeling. The proposed model can be used to evaluate the suitability of BHE applications with low thermal-gradient in southern California.

INTRODUCTION
The utilization of fossil fuels has surged significantly during the last half-century, resulting in enormous carbon dioxide (CO2) emissions and thus significant climate change. To tackle that, the United Nations, the G7 economies and many countries around the world have started or are going to promote the shift to renewable energy (UN DESA 2017; Gielen et al. 2019; G7 2021). Among different renewable energy, geothermal energy has been used for centuries and it is expected to meet 3%-5% of global demand by 2050 (Craig and Gavin 2018). Based on the depth of geothermal energy reservoirs, there are two major types of geothermal systems: shallow geothermal systems (≤400 m) and deep geothermal systems (&gt; 400 m) according to White (1966).