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Articles 1231 - 1260 of 2600
Full-Text Articles in Sustainability
Application Of Pneumatic Dth Hammer In Drilling Rescue Of Mine Accidents, Zhao Jiangpeng, Hao Shijun
Application Of Pneumatic Dth Hammer In Drilling Rescue Of Mine Accidents, Zhao Jiangpeng, Hao Shijun
Coal Geology & Exploration
As an efficient percussive rock breaking tool, pneumatic down-the-hole (DTH) hammer has played an important role in drilling rescue of mine accidents at home and abroad. Herein, the technical characteristics of pneumatic DTH hammer were described from the points of rock breaking mechanism, structure type, drilling method and specification, and the reverse circulation type and its characteristics of pneumatic DTH hammer were emphatically analyzed. Besides, the application of forward circulation drilling of pneumatic DTH hammer and the combined deviation correction drilling of pneumatic DTH hammer and mud screw in small diameter drilling, as well as the research progress of pneumatic …
Formation Mechanism Of Coalbed Methane In Dafosi Mine Field, Huanglong Coalfield, Liu Kaide, Yao Kaiwen, Chen Nengyuan, Fan Zhangqun, Li Shujia, Zheng Han, Yue Wenping, Li Xiaolong
Formation Mechanism Of Coalbed Methane In Dafosi Mine Field, Huanglong Coalfield, Liu Kaide, Yao Kaiwen, Chen Nengyuan, Fan Zhangqun, Li Shujia, Zheng Han, Yue Wenping, Li Xiaolong
Coal Geology & Exploration
Dafosi mine field is a typical low-rank coalbed methane (CBM) field in Binchang mining area of Huanglong Jurassic. There are many coalbed methane wells in the field, but few researches are performed on the formation mechanism of coalbed methane. Thus, it is of great guiding significance to clarify the geochemical characteristics and formation mechanism of coalbed methane (CBM) in the mine field, which could provide important basis for the analysis on productivity difference of high- and low-yield CBM Wells. For this reason, the samples of drained gas at the wellhead of six CBM wells, 22 coal samples of No.4 coal …
Digital Twin Technology Of Geological Information In Mining And Excavation Working Face, Li Peng, Cheng Jianyuan
Digital Twin Technology Of Geological Information In Mining And Excavation Working Face, Li Peng, Cheng Jianyuan
Coal Geology & Exploration
The mine geology transparency is the basis for the intelligent coal mine construction. 3D geological modeling is an important measure for realizing the mine geology transparency. In the geological modeling of the previous working face, there are problems including the discrepancy between the interpolation algorithm and the geological law, the low fusion level of the multi-source heterogeneous geological data, and the seldom coupling between the coal mine production equipment and the geological information. The concept of the digital twin of the geological information about coal mine working face was proposed, the discrete smooth interpolation (DSI) algorithm was adopted, and the …
Impact Of Voids And Backfill On Seismic Wave Velocity-Preliminary Results, Zarina Mukhamedyarova, Fidelis Suorineni, Temirlan Aldubay, Gylym Sapinov
Impact Of Voids And Backfill On Seismic Wave Velocity-Preliminary Results, Zarina Mukhamedyarova, Fidelis Suorineni, Temirlan Aldubay, Gylym Sapinov
Journal of Sustainable Mining
In this study, laboratory experiments were conducted on discrete physical models that mimic mining effects to better understand the impact of continuous changes in mining environments on seismic wave velocities. The discrete physical models are represented by concrete and granite cubic samples of different sizes with holes of different diameters filled and unfilled with cemented sand backfill of different cement-sand content ratios. The hole diameters range from 0 to 150 mm in block sizes ranging from 150 mm to 450 mm in increments of 75 mm. The increasing hole size mimics increasing extraction in the mine with time. Cemented sand …
Predicting The Stability Of Open Stopes Using Machine Learning, Alicja Szmigiel, Derek B. Apel
Predicting The Stability Of Open Stopes Using Machine Learning, Alicja Szmigiel, Derek B. Apel
Journal of Sustainable Mining
The Mathews stability graph method was presented for the first time in 1980. This method was developed to assess the stability of open stopes in different underground conditions, and it has an impact on evaluating the safety of underground excavations. With the development of technology and growing experience in applying computer sciences in various research disciplines, mining engineering could significantly benefit by using Machine Learning. Applying those ML algorithms to predict the stability of open stopes in underground excavations is a new approach that could replace the original graph method and should be investigated. In this research, a Potvin database …
Quantifying The Influence Of Variations In Rock Mass Properties On Stope Stability, Shahé Shnorhokian, Hani Mitri
Quantifying The Influence Of Variations In Rock Mass Properties On Stope Stability, Shahé Shnorhokian, Hani Mitri
Journal of Sustainable Mining
Variations in rock mass properties are well-established in rock mechanics and underground mining. The literature is replete with methods of assessing them and determining values that are used in design or numerical analysis. In this paper, a simplified 3D model is constructed for a tabular orebody in the Canadian Shield and instability is quantified using the ”brittle shear ratio” criterion to calculate the volume at risk. A 1-4-7 stope pillar sequence is implemented on four active levels, and three variations in the properties of the host formation are assessed. It is observed that the locations of ore at risk follow …
Prospects For Thiourea As A Leaching Agent In Colombian Gold Small-Scale Mining: A Comprehensive Review, Johana Borda, Robinson Torres
Prospects For Thiourea As A Leaching Agent In Colombian Gold Small-Scale Mining: A Comprehensive Review, Johana Borda, Robinson Torres
Journal of Sustainable Mining
Thiourea, as an alternative medium, is one of the most promising leaching agents for gold recovery by its commercial benefits and research challenges associated with performance and environmental impacts. This review article describes the operational conditions for the use of Thiourea vs cyanide, its chemistry, limitations, toxicity factors, environment, and recovery processes. Although thiourea gold extraction processes have not been applied on a large scale due to the instability of the reagent, its potential to overcome the limitations of cyanide is attractive to the process; with pH, potential, oxidant dosage, and temperature control, solubilized gold thiourea species are achieved. These …
Panel Destressing Strategies For Remnant Pillar Extraction, Isaac Vennes, Hani Mitri
Panel Destressing Strategies For Remnant Pillar Extraction, Isaac Vennes, Hani Mitri
Journal of Sustainable Mining
Large-scale panel destressing is a rockburst mitigation technique employed in deep hard rock mines during remnant pillar extraction. Panels are choke blasted in the pillar footwall to cutoff the far-field major stress in the mining area and deviate them around the pillar. In this study, the effects of panel geometry and far-field stress magnitude are investigated. Destress blast performance is assessed by measuring change to the energy release rate (ERR) of all mining steps during the extraction of a simplified remnant pillar due to destressing. It is demonstrated that the energy release rate (ERR) of critical stopes is reduced by …
Seismic Activity And Flooding Of Hard Coal Mines In The Ostrava-Karvina Coalfield, Petr Konicek, Eva Jirankova, Vlastimil Kajzar, Jan Schreiber, Pavel Malucha, Kristyna Schuchova
Seismic Activity And Flooding Of Hard Coal Mines In The Ostrava-Karvina Coalfield, Petr Konicek, Eva Jirankova, Vlastimil Kajzar, Jan Schreiber, Pavel Malucha, Kristyna Schuchova
Journal of Sustainable Mining
The termination of mining activities often results in post-mining problems and risks. One of these issues is the flooding of mines. Long-term mining in the Ostrava and Petrvald sub-basins in the Upper Silesian Coal Basin finished in 1994. Tens of coal seams were mined here, and the depth of mining reached more than 1000 m below the surface. Flooding of the Ostrava sub-basin started in 1994. The Ostrava and Petrvald sub-basins were flooded from one half only to prevent water from flooding into the Karvina sub-basin, where mining continued. The continual pumping of water has been carried out ever since. …
Numerical Modelling Of Destress Blasting – A State-Of-The-Art Review, Shuting Miao, Petr Konicek, Peng-Zhi Pan, Hani Mitri
Numerical Modelling Of Destress Blasting – A State-Of-The-Art Review, Shuting Miao, Petr Konicek, Peng-Zhi Pan, Hani Mitri
Journal of Sustainable Mining
As a proactive mine safety measure against the occurrence of rockburst, destress blasting has been applied to numerous mining conditions to precondition highly stressed rock mass to mitigate the risk of rockburst occurrence in deep mines as well as in deep underground constructions. However, the application of destress blasting mostly depends on engineering experience, while its mechanism and efficiency have not been well understood. Rapid advances in computer technology have made numerical simulation an economical and effective method to study the rock blasting effect. Enormous research efforts have been made to numerically investigate the blasting fracture mechanism, optimize blasting design, …
Analysis Of The Application Of Methane-Bearing Capacity Test Methods In The Conditions Of Polish Mining, Marcin Karbownik
Analysis Of The Application Of Methane-Bearing Capacity Test Methods In The Conditions Of Polish Mining, Marcin Karbownik
Journal of Sustainable Mining
The methane hazard is one of the natural hazards occurring in hard coal mining. The content of natural methane in hard coal seams, the so-called methane-bearing capacity, is one of the key parameters that allow for proper assessment of the methane hazard and the state of the threat of gas and rock outbursts. For safety purposes, there is a constant need to improve the methods for the determination of this parameter. In the conditions of Polish mining, the method used for methane-bearing capacity determination is the direct drill cuttings method. This paper contains a comparative study presenting three different methods …
Proposed Design Fire Scenarios For Underground Hard Rock Mines, Rickard Hansen
Proposed Design Fire Scenarios For Underground Hard Rock Mines, Rickard Hansen
Journal of Sustainable Mining
Given the complexity and uniqueness of underground hard rock mines, the application of the design fire scenario approach is recommended when evaluating fire safety in mines. Providing a full set of design fire scenarios – ensuring that several important life safety aspects are covered – for a mine can be challenging. The question is whether a catalogue of potential clusters of design fire scenarios could be developed, covering important aspects found underground? Given the general lack of research into design fires in the mining industry, this paper provides a unique analysis of design fire scenarios in underground hard rock mines. …
Effect Of Mining And Geology On Mining-Induced Seismicity – A Case Study, Heba Khalil, Tuo Chen, Yu-Hang Xu, Hani Mitri
Effect Of Mining And Geology On Mining-Induced Seismicity – A Case Study, Heba Khalil, Tuo Chen, Yu-Hang Xu, Hani Mitri
Journal of Sustainable Mining
Mining-induced seismicity is a commonly occurring phenomenon in underground mines. This poses a greater challenge to the safety of the mining operation. This paper presents a case study of the Young-Davidson mine in northern Ontario, Canada, where seismic events of magnitude Mn 2.0+ have been observed at mining depths of 600 to 800 m below the surface. The occurrence of large seismic events at such shallow depths is the key issue of this study. A comprehensive study of the microseismic database has been conducted to discern the root causes for the unusually strong seismic activities recorded at shallow depths. The …
Shaft Liquidation Method Adjusted For High Precipitation Associated With Climate Change Impact, Jan Szymała, Joanna Całus Moszko, Ewa Janson, Dagmara Sobczak, Stanisław Konsek
Shaft Liquidation Method Adjusted For High Precipitation Associated With Climate Change Impact, Jan Szymała, Joanna Całus Moszko, Ewa Janson, Dagmara Sobczak, Stanisław Konsek
Journal of Sustainable Mining
In connection with the implementation of the international project TEXMIN within the framework of the RFCS fund, a project for the liquidation of the Głowacki Shaft in Rybnik (Poland) was undertaken, which takes into account the effects of climate change, i.e. evaluation of the increase of precipitation in the region. In addition to the standard research undertaken before liquidation activities, precipitation data recorded by the Institute of Meteorology and Water Management from 1995 to 2019 was collected and the precipitation variability was analysed. As a result, a method for liquidation of the shaft was selected consisting of constructing a permeable …
Uncertainty Analysis Of Operational Conditions In Selective Artificial Ground Freezing Applications, Ahmad Zueter, Saad Akhtar, Agus Sasmito
Uncertainty Analysis Of Operational Conditions In Selective Artificial Ground Freezing Applications, Ahmad Zueter, Saad Akhtar, Agus Sasmito
Journal of Sustainable Mining
Artificial ground freezing (AGF) systems are susceptible to uncertain parameters highly affecting their performance. Particularly, selective artificial ground freezing (S-AGF) systems involve several uncertain operational conditions. In this study, uncertainty analysis is conducted to investigate four operational parameters: 1) coolant inlet temperature, 2) coolant flow rate, 3) pipes emissivity, and 4) pipes eccentricity. A reduced-order model developed and validated in our previous work for field-scale applications is exploited to simulate a total of 5,000 cases. The uncertain operational parameters are set according to Monte Carlo analysis based on field observations of a field-scale freeze-pipe in the mining industry extending to …
Carbonised Fluidised Fly Ash (Cffa); A New Product For Mining Engineering Purposes (Discussion Of Possible Applications), Marian Jacek Łączny, Przemysław Rompalski
Carbonised Fluidised Fly Ash (Cffa); A New Product For Mining Engineering Purposes (Discussion Of Possible Applications), Marian Jacek Łączny, Przemysław Rompalski
Journal of Sustainable Mining
The article presents and summarises the current state of research and laboratory results on the carbonation of fly ash with carbon dioxide in the context of its use in mining engineering. Based on previous publications and patent applications, the possibilities of using carbonated fly ash from fluidised bed boilers for the following applications were discussed: securing excavations particularly susceptible to fire hazards, shotcreting and securing longwalls and supports, constructing cases, securing decommissioned shafts, and others, which means wherever the use of cement is required. It was pointed out that the removal of excess free calcium oxide makes it possible to …
Addressing Specific Safety And Occupational Health Challenges For The Canadian Mines Located In Remote Areas Where Extreme Weather Conditions Dominate, Rachid Halabi, Mustafa Kumral
Addressing Specific Safety And Occupational Health Challenges For The Canadian Mines Located In Remote Areas Where Extreme Weather Conditions Dominate, Rachid Halabi, Mustafa Kumral
Journal of Sustainable Mining
The number of mining operations is increasing in the Canadian North, where extreme weather conditions govern. Currently, many mine development projects are also in progress in this region. These mines’ working atmosphere and employment circumstances are highly different from regular mines. One of the main differences is the special safety issues of the Canadian North. The primary sources of these special issues are: the difficulty of finding skilled employees; high employee turnover rate; insufficient training and certification requirements; delicate employment circumstances affecting the psychological well-being of employees; permafrost; mine inspection challenges; inventory and logistic hardship; and the legislative and regulative …
Table Of Contents, The Editors
Study On Mechanical Mechanism Of Roof Fracture Evolution In Deep Stope With Variable Face Length, Wang Xinfeng, Lu Mingyuan
Study On Mechanical Mechanism Of Roof Fracture Evolution In Deep Stope With Variable Face Length, Wang Xinfeng, Lu Mingyuan
Coal Geology & Exploration
Irregular coal seam mining is easy to cause the problems such as roof stress concentration and abnormal ground pressure behavior. In order to explore the roof fracture law and the structural evolution characteristics of stope with variable length, the roof structure models with four types of boundary conditions were established and analyzed using the small-deflection thin plate bending theory in view of the geometric characteristics and mechanical causes of the abrupt stope with the inclined length of working face changing from small to large in various mining stages. Meanwhile, the roof fracture law and macro-mechanical response were analyzed by MATLAB …
Occurrence Law Of Coal Seam Gas Under Influence Of Normal Fault Zone In Coal Measures, Xiao Peng, Wu Mingchuan, Shuang Haiqing, Han Kai, Gao Zhen, Cheng Yueying
Occurrence Law Of Coal Seam Gas Under Influence Of Normal Fault Zone In Coal Measures, Xiao Peng, Wu Mingchuan, Shuang Haiqing, Han Kai, Gao Zhen, Cheng Yueying
Coal Geology & Exploration
The coal measure fault zone generated by the superimposition of the polytropic movement and multiple structure has important effects on the coal seam gas occurrence. The method of combining the geologic analysis, COMSOL Multiphysics numerical simulation and field data monitoring was adopted to analyze the interaction relations between the stress distribution characteristics and faults of the normal fault zone in the coal measure, study the coal seam permeability variation characteristics influenced by the normal fault zone in the coal measure, and simulate the gas migration status and concentration distribution condition after the formation of the normal fault zone. The coal …
Research On Permeability Model Of Coal Reservoir Along Producing Wellbores, Jia Lidan, Zhang Lin, Li Bobo, Wu Xuehai, Gao Zheng, Wang Zhonghui, Fu Jiale
Research On Permeability Model Of Coal Reservoir Along Producing Wellbores, Jia Lidan, Zhang Lin, Li Bobo, Wu Xuehai, Gao Zheng, Wang Zhonghui, Fu Jiale
Coal Geology & Exploration
Permeability is an important parameter to characterize gas flow. In order to ensure the safe and efficient gas drainage, it is necessary to explore the evolution characteristics of coal reservoir gas seepage at different positions from the producing wellbores. However, the effective stress, the gas adsorption/desorption capacity of coal matrix and the temperature of coal reservoir are constantly changing with the gas drainage, and even the drainage damage may occur, which makes the gas migration behavior in coal seam extremely complicated. In order to explore the seepage characteristics of coal reservoir gas during gas drainage, the space-time evolution function of …
Occurrence Modes And Stepwise Chemical Extraction Experiment Of Lithium In No.20 Coal Seam In Pu’An Mining Area, Guizhou Province, Cheng Chen, Song Yang, Zang Jingkun, Cheng Wei
Occurrence Modes And Stepwise Chemical Extraction Experiment Of Lithium In No.20 Coal Seam In Pu’An Mining Area, Guizhou Province, Cheng Chen, Song Yang, Zang Jingkun, Cheng Wei
Coal Geology & Exploration
Lithium (Li) is an important energy metal, and the global demand for Li has grown rapidly in recent years. The discovery of coal-associated Li deposits in China proves that coal mines may serve as a potential alternative of Li resources. No.20 coal seam in Pu’an mining area in Guizhou province of China was selected as the study object. The basic properties, mineral composition, elemental composition, and occurrence modes of Li of the raw coal and six density-graded samples (obtained through a float-sink test) were determined by using coal proximate analysis, optical microscope, X-Ray fluorescence spectroscopy (XRF), inductively coupled plasma mass …
Numerical Simulation On Evolution Law Of Overburden Fractures And Surface Cracks In Crossing Ditch Mining Of Shallow Coal Seam, Wei Jiangbo, Wang Shuangming, Song Shijie, Sun Qiang
Numerical Simulation On Evolution Law Of Overburden Fractures And Surface Cracks In Crossing Ditch Mining Of Shallow Coal Seam, Wei Jiangbo, Wang Shuangming, Song Shijie, Sun Qiang
Coal Geology & Exploration
Crossing ditch mining of shallow coal seam is common in northern Shaanxi mining area, which seriously threatens the safe production and the sound ecological development. The mining-induced overburden fractures and surface cracks are developed as a result of the extension and expansion of microcracks in rock mass. In order to more systematically study the evolution law of overburden microcracks in crossing ditch mining of shallow coal seam, a numerical model of particle flow in coal mining was established with the Particle Flow Code (PFC) numerical simulation platform according to the field ditch profile and borehole data under the background of …
Experimental Study On Stress Relaxation Characteristics Of Soft Dredger Fill Under Uu Triaxial Shear, Yang Aiwu, Yang Shaopeng, Qi Jiejie
Experimental Study On Stress Relaxation Characteristics Of Soft Dredger Fill Under Uu Triaxial Shear, Yang Aiwu, Yang Shaopeng, Qi Jiejie
Coal Geology & Exploration
Stress relaxation often occurs in the saturated soft clay with poor water permeability under the actual working condition at fast construction speed (fast loading rate), which brings huge hidden dangers to the safe operation of engineering practice. Herein, the unconsolidated undrained triaxial shear test was performed based on the soft dredger fill in Tianjin Binhai using the WF stress path triaxial instrument, and the influence law of such factors as the different initial strain, confining pressure, shear rate, sampling depth and structural properties of the soft dredger fill on its stress relaxation characteristics was analyzed accordingly. According to the test …
Spatial Variation Characteristics Of Soil Heavy Metal Speciation And Bioavailability In Coal Gangue Accumulation Area—Taking Fengfeng Mining Area As An Example, Sun Tao, Song Shijie, Chang Qing, Wang Chenchen, Zhang Yanjie, Peng Ruisi, Wang Yi
Spatial Variation Characteristics Of Soil Heavy Metal Speciation And Bioavailability In Coal Gangue Accumulation Area—Taking Fengfeng Mining Area As An Example, Sun Tao, Song Shijie, Chang Qing, Wang Chenchen, Zhang Yanjie, Peng Ruisi, Wang Yi
Coal Geology & Exploration
The surface accumulation of coal gangue is a typical form of ecological environment destruction in the eastern coal mining area of China, and the prevention and control of heavy metal pollution in the soil in the accumulation area has become a hot spot in the current research. Taking the shallow soil (with a vertical depth of 40 cm and below) around a coal gangue mountain (within a radius of 300 m) in use in the Fengfeng mining area of Hebei as the research object, the active state, iron manganese oxidation state, organic state and residue state of four kinds of …
Effect Of Initial Adhesion On Shear Strength And Deformation Characteristics Of Interfaces In Heterogeneous Soils, Zhu Yanbo, Yang Fanfan, Miao Shuaisheng, Li Futong, Zhang Yuxuan
Effect Of Initial Adhesion On Shear Strength And Deformation Characteristics Of Interfaces In Heterogeneous Soils, Zhu Yanbo, Yang Fanfan, Miao Shuaisheng, Li Futong, Zhang Yuxuan
Coal Geology & Exploration
In the Loess Plateau of China, the interface between the Loess and Hipparion Red Clay is widely distributed. The initial adhesion between this interfaces plays an important role in its shear strength. To investigate the effect of initial adhesion on shear strength and deformation characteristics of the interfaces, we firstly performed a series of direct shear experiments. Then, we discussed the effects of initial adhesion on failure mode, shear deformation and shear strength of interfaces. The results indicate that the failure modes of interfaces with initial adhesion and interfaces without initial adhesion are different. The initial adhesion improves the sliding …
Research And Application Progress Of Energy Underground Structures, Wen Jiwei, Hou Junlong, Liu Xinghong, Zeng Xian’En, Xiang Tian
Research And Application Progress Of Energy Underground Structures, Wen Jiwei, Hou Junlong, Liu Xinghong, Zeng Xian’En, Xiang Tian
Coal Geology & Exploration
Energy geostructure refers to a type of structure equipped with heat exchange pipe in the building foundation element and the underground structure, which has the functions of load bearing and heat exchange. It not only effectively saves the valuable and irreversible underground space resources, but also makes full use of the non-carbon based continuous, stable, safe and clean geothermal energy resources, thus having more advantages than the traditional Ground Source Heat Pump (GSHP). Herein, the concept, advantages, research and application progress of energy geostructure at home and abroad were systematically summarized. Moreover, the current situation of four common energy geostructures, …
Numerical Simulation Of The Influence Of Karst Structure On Heat Transfer Efficiency Of Buried Pipeline Group, Mu Xuan, Pei Peng, Zhou Xin, Tu Hongsheng
Numerical Simulation Of The Influence Of Karst Structure On Heat Transfer Efficiency Of Buried Pipeline Group, Mu Xuan, Pei Peng, Zhou Xin, Tu Hongsheng
Coal Geology & Exploration
The buried pipeline is the part where the rock mass heat pump system performs direct heat transfer with the ground. The water-bearing structure in the karst area is complex and diverse, which has a significant impact on the heat transfer and storage of the buried pipeline group. Herein, the heat transfer process of a group of 27 vertical buried pipelines in four geological structure types was simulated, including the non-karst structure, fractured karst structure, karst conduit structure and mixed karst structure. Meanwhile, comparison was made for the change of parameters, such as the temperature field in the rock mass, the …
Numerical Simulation On Azimuth Gamma Ray Detection Of Coal And Rock Interface, Chen Gang, Chen Long, Li Quanxin, Liu Zhiyi
Numerical Simulation On Azimuth Gamma Ray Detection Of Coal And Rock Interface, Chen Gang, Chen Long, Li Quanxin, Liu Zhiyi
Coal Geology & Exploration
In order to meet the requirements of geosteering drilling with LWD azimuth gamma, the response value of gamma ray intensity under different surrounding rock thicknesses and absorption coefficients was studied by numerical simulation. Meanwhile, the variation of special and physical characteristics reflected by API value measured by gamma detector under the radioactive formation conditions was simulated and analyzed. On this basis, the geological model of the three layers of coal, mudstone and limestone of 8-sectors azimuth gamma ray drilling was established to simulate the identification process of roof and floor of coal bed drilled. The simulation results show that the …
Time-To-Depth Conversion Accuracy Analysis And Improvement Method For Inclined Coal Bed, Wang Huifeng, Fu Chao, Li Guo, Chen Tongjun
Time-To-Depth Conversion Accuracy Analysis And Improvement Method For Inclined Coal Bed, Wang Huifeng, Fu Chao, Li Guo, Chen Tongjun
Coal Geology & Exploration
The average-velocity method is the most commonly-used time-to-depth conversion technology for the seismic survey of coalbed. But for the steeply-inclined coalbed, the average velocity changes rapidly laterally, and the interpretation accuracy varies greatly, so that the intelligent coal mining could not be assured effectively. Herein, the accuracy of various average-velocity-interpolation methods was discussed by analyzing a steeply-inclined coalbed model and a practical 3D seismic mining area and appropriate improvement methods were proposed accordingly. The calculation results of a forward model show that the bottom elevation accuracy of coalbed is greatly affected by the locations of interpolation points in the case …