Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(1).09
T. Pham, J. Parnell
Diagenesis in the Permo-Triassic New Red Sandstone, Isle of Arran is characterized by early cementation of hematite, clay, and calcite minerals, followed by burial compaction, quartz, feldspar, and pyrite cementation. Cataclasis post-dated the quartz and feldspar cementation and reduced the grain and pore aperture size in deformed samples. Samples with cataclastic bands typically have 18% porosity and 8.81 mD permeability on average. Whereas, undeformed samples have an average porosity of 22% and an average permeability of 381 mD. Cataclasis was not as important as diagenesis in controlling sandstone porosity and permeability. However, cataclasis resulted in lower porosity and very poor to medium permeability in deformed samples. Cataclastic bands compartmentalize reservoir sands and cause a high heterogeneity in undeformed porous sandstones. Poikilotopic and blocky calcite cement postdates early clay and hematite cement. In addition, burial quartz and feldspar overgrowths also postdate the early clay and hematite. However, the poikilotopic calcite fills in framework grains that have larger void volumes than the grain/grain contacts where quartz overgrowths are present. Cataclasis resulted in fracturing of quartz and feldspar overgrowths. Therefore, the cataclasis occurred after the development of quartz and feldspar cementation. Dissolution postdated the formation of authigenic feldspar and pyrite formation resulted from hematite reduction. The distributions of grain and pore sizes against cumulative mercury volumes in studied samples shows a high level of reduction of grain and pore aperture sizes for deformed samples from single-cataclastic and multi-cataclastic bands. The distribution of apex volumes illustrates that the effective mercury porosity of the multi-cataclastic band sample may be reduced up to > 2 times in comparison to undeformed samples. However, the sample of a thin single cataclastic band has only a slightly lower apex volume in comparison to the host sample.
{"title":"Diagenesis and the effects of cataclastic deformation on the Permo-Triassic New Red Sandstone, Isle of Arran, Scotland","authors":"T. Pham, J. Parnell","doi":"10.46326/jmes.2023.64(1).09","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(1).09","url":null,"abstract":"Diagenesis in the Permo-Triassic New Red Sandstone, Isle of Arran is characterized by early cementation of hematite, clay, and calcite minerals, followed by burial compaction, quartz, feldspar, and pyrite cementation. Cataclasis post-dated the quartz and feldspar cementation and reduced the grain and pore aperture size in deformed samples. Samples with cataclastic bands typically have 18% porosity and 8.81 mD permeability on average. Whereas, undeformed samples have an average porosity of 22% and an average permeability of 381 mD. Cataclasis was not as important as diagenesis in controlling sandstone porosity and permeability. However, cataclasis resulted in lower porosity and very poor to medium permeability in deformed samples. Cataclastic bands compartmentalize reservoir sands and cause a high heterogeneity in undeformed porous sandstones. Poikilotopic and blocky calcite cement postdates early clay and hematite cement. In addition, burial quartz and feldspar overgrowths also postdate the early clay and hematite. However, the poikilotopic calcite fills in framework grains that have larger void volumes than the grain/grain contacts where quartz overgrowths are present. Cataclasis resulted in fracturing of quartz and feldspar overgrowths. Therefore, the cataclasis occurred after the development of quartz and feldspar cementation. Dissolution postdated the formation of authigenic feldspar and pyrite formation resulted from hematite reduction. The distributions of grain and pore sizes against cumulative mercury volumes in studied samples shows a high level of reduction of grain and pore aperture sizes for deformed samples from single-cataclastic and multi-cataclastic bands. The distribution of apex volumes illustrates that the effective mercury porosity of the multi-cataclastic band sample may be reduced up to > 2 times in comparison to undeformed samples. However, the sample of a thin single cataclastic band has only a slightly lower apex volume in comparison to the host sample.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123399974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).02
Liem D. Nguyen, Luc Manh Nguyen, Thanh Van Duong, A. Tran, Anh-Tuyet Thi Phung
This study demonstrates an integrated approach of remote sensing, geographic information system (GIS), and Analytical Hierarchy Process (AHP) method to create a landslide susceptibility map for Muong Lay town and its vicinity in Northern midland and mountainous of Vietnam. Nine landslide-related factors, including petrological composition, active fault density, slope, drainage density, the difference in height per unit area, land cover, soil texture, maximum daily rainfall, and earthquake density were created using ground or remotely sensed data in a GIS environment. Weight for each factor was assigned using AHP depending on its relative importance in landslide occurrence in the study area through literature review. The landslide susceptibility map was generated using a weighted linear combination method in GIS and categorized into five susceptible classes namely, very low, low, moderate, high, and very high using quantile classification. The results revealed that 29% of the study area is at very low susceptibility, 24% at low susceptibility, 21% of moderate susceptibility, 15% of high susceptibility, and 11% of very high susceptibility area coverage. The effectiveness of these results was checked by computing the area under Receiver Operating Characteristic curve (AUC) which showed a satisfactory result of 63.3%. Most of the recorded landslide events were located in high and very high susceptibility areas. These findings could be useful to planners and decision-makers in land use planning and slope management to prevent or reduce future landslides.
{"title":"Landslide susceptibility zonation using geospatial techniques and Analytical Hierarchy Process: A case study in Muong Lay town and its vicinity","authors":"Liem D. Nguyen, Luc Manh Nguyen, Thanh Van Duong, A. Tran, Anh-Tuyet Thi Phung","doi":"10.46326/jmes.2023.64(2).02","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).02","url":null,"abstract":"This study demonstrates an integrated approach of remote sensing, geographic information system (GIS), and Analytical Hierarchy Process (AHP) method to create a landslide susceptibility map for Muong Lay town and its vicinity in Northern midland and mountainous of Vietnam. Nine landslide-related factors, including petrological composition, active fault density, slope, drainage density, the difference in height per unit area, land cover, soil texture, maximum daily rainfall, and earthquake density were created using ground or remotely sensed data in a GIS environment. Weight for each factor was assigned using AHP depending on its relative importance in landslide occurrence in the study area through literature review. The landslide susceptibility map was generated using a weighted linear combination method in GIS and categorized into five susceptible classes namely, very low, low, moderate, high, and very high using quantile classification. The results revealed that 29% of the study area is at very low susceptibility, 24% at low susceptibility, 21% of moderate susceptibility, 15% of high susceptibility, and 11% of very high susceptibility area coverage. The effectiveness of these results was checked by computing the area under Receiver Operating Characteristic curve (AUC) which showed a satisfactory result of 63.3%. Most of the recorded landslide events were located in high and very high susceptibility areas. These findings could be useful to planners and decision-makers in land use planning and slope management to prevent or reduce future landslides.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132800261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(1).03
Hong-Minh Thi Nguyen, H. T. Pham
Probe permeameter (also known as Mini-permeameter) has been widely used in many field and laboratory applications where in-situ measurements and spatial distributions of permeability are needed. Mini-permeameter measurements have become popular techniques for collecting localized permeability measurements in both laboratory and field applications. It is designed to obtain fast, cheap, intensive and non-destructive permeability measurements and to describe the spatial arrangement of permeability. Currently the probe permeability meter is designed and manufactured as a portable air permeability for field applications and to be used in outcrop and core samples. In this instrument, the permeability is measured by air that flows from the samples to be measured into an air chamber through the vacuum created by increasing the volume of the chamber. In carbonate reservoirs, permeability predicted from pure porosity-permeability empirical relationship is often difficult due to complex rock pore systems leading to poor porosity-permeability relations. Once the relationships between permeability and textural rock properties are clearly established in carbonates, they can provide better permeability predictions from porosity data. Rock texture is an important parameter for the understanding of the porosity and permeability characteristics of carbonate reservoirs. In addition to predicting carbonate rock facies from routine core plug porosity and permeability measurements, there is an approach to determine carbonate reservoir facies based on core-plug probe permeability. The results of the probe permeability measurements, in this paper, can be used in combination with the porosity values derived from the well logs to classify and predict rock facies in carbonate cored or uncored reservoirs in Phu Khanh basin.
{"title":"Prediction of carbonate rock facies from core probe permeability measurements and well log data: a case study from carbonate reservoirs, Phu Khanh basin","authors":"Hong-Minh Thi Nguyen, H. T. Pham","doi":"10.46326/jmes.2023.64(1).03","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(1).03","url":null,"abstract":"Probe permeameter (also known as Mini-permeameter) has been widely used in many field and laboratory applications where in-situ measurements and spatial distributions of permeability are needed. Mini-permeameter measurements have become popular techniques for collecting localized permeability measurements in both laboratory and field applications. It is designed to obtain fast, cheap, intensive and non-destructive permeability measurements and to describe the spatial arrangement of permeability. Currently the probe permeability meter is designed and manufactured as a portable air permeability for field applications and to be used in outcrop and core samples. In this instrument, the permeability is measured by air that flows from the samples to be measured into an air chamber through the vacuum created by increasing the volume of the chamber. In carbonate reservoirs, permeability predicted from pure porosity-permeability empirical relationship is often difficult due to complex rock pore systems leading to poor porosity-permeability relations. Once the relationships between permeability and textural rock properties are clearly established in carbonates, they can provide better permeability predictions from porosity data. Rock texture is an important parameter for the understanding of the porosity and permeability characteristics of carbonate reservoirs. In addition to predicting carbonate rock facies from routine core plug porosity and permeability measurements, there is an approach to determine carbonate reservoir facies based on core-plug probe permeability. The results of the probe permeability measurements, in this paper, can be used in combination with the porosity values derived from the well logs to classify and predict rock facies in carbonate cored or uncored reservoirs in Phu Khanh basin.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122911634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(1).06
H. Vu, Do Duc Nguyen, G.P. Phan, V. Le, Hai Hoang Ninh
Fault transmissibility multipliers are a simple way of accounting for the effects of faults on fluid flow across fault plans in history matching of production simulation models. Fault transmissibility multipliers can be calculated using parameters such as fault clay, fault smear, thickness, and permeability. In this study, three emperical methods given by Manzocchi et al. (1999), Jolley et al. (2007), and Sperrevik et al. (2002) have been applied to the Oligocene sandstone reservoir, Tay Ho Field. The Oligocene reservoir is a complicated sandstone that was deposited in alluvial-fluvial and lacustrine environments, trapped by both stratigraphic and structural types, sandbody isolated by multi-activated faults. Fault sealing is one of the key factors controlling hydrocarbon accumulations and trap volume and can have a significant influence on reservoir performance during production. Furthermore, the prospective of structural or combination traps in stacked clastic reservoir settings that are typically found in many of the known hydrocarbon provinces in the Cuu Long basin, often critically hinges on the presence of a working fault side seal. Based on a thorough understanding of the key controls on fault seal risk and retention capacity, a consistent methodology to access these factors across a prospect portfolio is essential to achieve a balanced prospect ranking and an accurate assessment of prospect success volumes. In the process workflow built by PVEP Blocks 01/97 & 02/97, the assessment of fault seal capacity and compartmentalization in the Oligocene reservoir have been incorperated by using fault deformation, displacement, juxtaposition, fault zone thickness, shale gouge ratio (SGR), shale smear factor (SSF), clay smear potential (CSP), fault thickness and permeability. In our research, the Sperrevik et al. (2002) method provides the best historical match and most logical geological evidence; thus, it shall be used for dynamic models and further studies.
在生产模拟模型的历史拟合中，断层传递率乘数是考虑断层对断层平面流体流动影响的一种简便方法。断层透射率乘数可以通过断层粘土、断层涂抹、断层厚度和渗透率等参数来计算。本研究将Manzocchi等人(1999)、Jolley等人(2007)和Sperrevik等人(2002)给出的三种经验方法应用于Tay Ho油田渐新统砂岩储层。渐新统储层是一种沉积于冲积-河流-湖泊环境的复杂砂岩，受地层和构造类型的双重束缚，砂体被多活化断裂隔离。断层封闭性是控制油气成藏和圈闭体积的关键因素之一，对油藏生产过程中的动态具有重要影响。此外，叠置碎屑岩储层中构造圈闭或组合圈闭的前景(通常在Cuu Long盆地的许多已知油气省中发现)往往关键取决于是否存在有效的断层侧密封。基于对断层封闭性风险和保留能力的关键控制因素的全面了解，在整个勘探组合中使用一致的方法来获取这些因素对于实现平衡的勘探排名和准确评估勘探成功量至关重要。在PVEP 01/97区块和02/97区块建立的流程流程中，通过断层变形、位移、并置、断裂带厚度、页岩泥比(SGR)、页岩涂抹因子(SSF)、粘土涂抹势(CSP)、断层厚度和渗透率等指标，对渐新统储层断层封闭性和分区性进行了综合评价。在我们的研究中，Sperrevik et al.(2002)的方法提供了最好的历史匹配和最符合逻辑的地质证据;因此，它应该用于动态模型和进一步的研究。
{"title":"3D dynamic fault sealing capacity modelling to improve history matching: a case study in Oligocene reservoir, Tay Ho Field, Blocks A, Cuu Long basin, Offshore","authors":"H. Vu, Do Duc Nguyen, G.P. Phan, V. Le, Hai Hoang Ninh","doi":"10.46326/jmes.2023.64(1).06","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(1).06","url":null,"abstract":"Fault transmissibility multipliers are a simple way of accounting for the effects of faults on fluid flow across fault plans in history matching of production simulation models. Fault transmissibility multipliers can be calculated using parameters such as fault clay, fault smear, thickness, and permeability. In this study, three emperical methods given by Manzocchi et al. (1999), Jolley et al. (2007), and Sperrevik et al. (2002) have been applied to the Oligocene sandstone reservoir, Tay Ho Field. The Oligocene reservoir is a complicated sandstone that was deposited in alluvial-fluvial and lacustrine environments, trapped by both stratigraphic and structural types, sandbody isolated by multi-activated faults. Fault sealing is one of the key factors controlling hydrocarbon accumulations and trap volume and can have a significant influence on reservoir performance during production. Furthermore, the prospective of structural or combination traps in stacked clastic reservoir settings that are typically found in many of the known hydrocarbon provinces in the Cuu Long basin, often critically hinges on the presence of a working fault side seal. Based on a thorough understanding of the key controls on fault seal risk and retention capacity, a consistent methodology to access these factors across a prospect portfolio is essential to achieve a balanced prospect ranking and an accurate assessment of prospect success volumes. In the process workflow built by PVEP Blocks 01/97 & 02/97, the assessment of fault seal capacity and compartmentalization in the Oligocene reservoir have been incorperated by using fault deformation, displacement, juxtaposition, fault zone thickness, shale gouge ratio (SGR), shale smear factor (SSF), clay smear potential (CSP), fault thickness and permeability. In our research, the Sperrevik et al. (2002) method provides the best historical match and most logical geological evidence; thus, it shall be used for dynamic models and further studies.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128155018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).03
Hung V. Nguyen, S. Bui, Nu Thi Nguyen, Luan Nhat Vo, C. Vo, Dat Tuan Nguyen
Liquefaction of sand is not a rare geological phenomenon. When it happens, it causes great damage to people. However, 1 District, Ho Chi Minh city where despite being a leading economic and political zone of Ho Chi Minh city, where many buildings with different loads and metro lines have been and will be rebuilt, but liquefaction potential has not been assessed. This paper presents a study on liquefaction potential of sand belonging to the Pleistocene sand lithological complex of marine origin on amSQ13 in 1 District, Ho Chi Minh based on standard penetration test (SPT) with different peak ground acceleration scenarios. Research results show that, when the peak ground acceleration amax = 0.0848 g, few points in this area occur liquefaction. However, when peak ground acceleration increased, specifically amax = 0.1 g and amax= 0.15 g, there were 8% and 68% of the survey points in the area where liquefaction occurred, respectively. The study also shows that, with a depth of about 20m, liquefaction in 1 District is still possible with amax = 0.1 g and amax = 0.15 g. The research results contribute to additional references for researchers and urban spatial planning in this area.
{"title":"Assessment of liquefaction potential of sand distributed in the 1 District, Ho Chi Minh city","authors":"Hung V. Nguyen, S. Bui, Nu Thi Nguyen, Luan Nhat Vo, C. Vo, Dat Tuan Nguyen","doi":"10.46326/jmes.2023.64(2).03","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).03","url":null,"abstract":"Liquefaction of sand is not a rare geological phenomenon. When it happens, it causes great damage to people. However, 1 District, Ho Chi Minh city where despite being a leading economic and political zone of Ho Chi Minh city, where many buildings with different loads and metro lines have been and will be rebuilt, but liquefaction potential has not been assessed. This paper presents a study on liquefaction potential of sand belonging to the Pleistocene sand lithological complex of marine origin on amSQ13 in 1 District, Ho Chi Minh based on standard penetration test (SPT) with different peak ground acceleration scenarios. Research results show that, when the peak ground acceleration amax = 0.0848 g, few points in this area occur liquefaction. However, when peak ground acceleration increased, specifically amax = 0.1 g and amax= 0.15 g, there were 8% and 68% of the survey points in the area where liquefaction occurred, respectively. The study also shows that, with a depth of about 20m, liquefaction in 1 District is still possible with amax = 0.1 g and amax = 0.15 g. The research results contribute to additional references for researchers and urban spatial planning in this area.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122046616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(1).04
Anh T. Truong, Tam T. Le, N. D. Dang, T. Do, Lap Quoc Lai, Lan Nguyen
Fault-seal analysis has long been applied for predicting potential hydrocarbon column for mitigating risk in exploration and appraisals. Than Nong 1B structure in Block 05-1(a), located nearby Dai Hung field, is a fault-bounding structure; thus, the fault seal capacity plays a major role in trapping hydrocarbon. In this study, the H50 reservoir is taken as an example of how fault-bounded prospects are evaluated in Block 05-1(a). For the case of Than Nong 1B, to meaningfully determine the potential of the structure, the fault geometric analysis is conducted to fully understand the 3D geometry of the structure. Moreover, vertical displacement of the faults is inspected to ensure the quality of input data and to understand how faults and horizons affect each other. After structural description conducted, the study applies all common methods of fault-seal analysis from the 1980s to the newest workflow published in 2016, such as 3D sand-shale juxtaposition analysis, SGR analysis, height-column-prediction algorithms by Yielding et al. (2010). The results of these methods are then combined by using Trap analysis workflow, proposed by Peter Bretan in 2017, to determine a unique location of fault leak point defining the trappable hydrocarbon column of the structure. The results suggest that the faults in Than Nong 1B prospect are able to hold a maximum column of 183 m hydrocarbon in H50 reservoir, significantly higher than the column of 125 m hydrocarbon defined by Fault-leak point. Furthermore, this study also proves that the Trap analysis is an effective method for evaluating structures with high level of fault linkage.
{"title":"Application of deterministic fault-seal analysis for fault-bounding trap: a case study in Than Nong 1B prospect, Block 05-1(a), Nam Con Son basin, offshore Vietnam","authors":"Anh T. Truong, Tam T. Le, N. D. Dang, T. Do, Lap Quoc Lai, Lan Nguyen","doi":"10.46326/jmes.2023.64(1).04","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(1).04","url":null,"abstract":"Fault-seal analysis has long been applied for predicting potential hydrocarbon column for mitigating risk in exploration and appraisals. Than Nong 1B structure in Block 05-1(a), located nearby Dai Hung field, is a fault-bounding structure; thus, the fault seal capacity plays a major role in trapping hydrocarbon. In this study, the H50 reservoir is taken as an example of how fault-bounded prospects are evaluated in Block 05-1(a). For the case of Than Nong 1B, to meaningfully determine the potential of the structure, the fault geometric analysis is conducted to fully understand the 3D geometry of the structure. Moreover, vertical displacement of the faults is inspected to ensure the quality of input data and to understand how faults and horizons affect each other. After structural description conducted, the study applies all common methods of fault-seal analysis from the 1980s to the newest workflow published in 2016, such as 3D sand-shale juxtaposition analysis, SGR analysis, height-column-prediction algorithms by Yielding et al. (2010). The results of these methods are then combined by using Trap analysis workflow, proposed by Peter Bretan in 2017, to determine a unique location of fault leak point defining the trappable hydrocarbon column of the structure. The results suggest that the faults in Than Nong 1B prospect are able to hold a maximum column of 183 m hydrocarbon in H50 reservoir, significantly higher than the column of 125 m hydrocarbon defined by Fault-leak point. Furthermore, this study also proves that the Trap analysis is an effective method for evaluating structures with high level of fault linkage.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131624429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).09
Chung Van Pham, C. Le, Long Quoc Nguyen, Ha Thi Thu Le, Anh Tuan Nhu Nguyen, Hung Nguyen, H. Nguyen
Tram rail transport is one of the important transport systems in underground coal mines. The stability of the tramway system in a mine is influenced by many factors, such as geological and mining conditions. In order to evaluate the stability of tramway tracks in underground coal mines, monitoring activities are carried out periodically. This activity is to provide accurate data on the current status of the rail system, early detection of displacement and deformation of the system. This paper presents the results of monitoring tram tracks in underground coal mines by the terrestrial laser scanning technology (TLS). The objective of the study are to evaluate the capacity of TLS in monitoring tram tracks in underground coal mines, and to propose a workflow for this activity. The experiment was held at the tramway in the main transport tunnel at the level of -350 m in the Nui Beo underground coal mine. A procedure was proposed, including the planning, collecting data in the field, data processing, and analyzing data. The surveing equipment was used, including: (1) a Topcon GLS 2,000 scanner for the TLS survey, (2) Digital leveling for measuring the elevation of the rails, (3) a tape for measuring the distance between the rails. The measurement of the distance between two railway lines were performed on the TLS point cloud. The comparison between TLS and the tape showed that the maximum difference was less than 3 mm and met the requirements of the monitoring of tram tracks in underground coal mines.
{"title":"Monitoring tram rail transport in underground coal mines using terrestrial laser scanning","authors":"Chung Van Pham, C. Le, Long Quoc Nguyen, Ha Thi Thu Le, Anh Tuan Nhu Nguyen, Hung Nguyen, H. Nguyen","doi":"10.46326/jmes.2023.64(2).09","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).09","url":null,"abstract":"Tram rail transport is one of the important transport systems in underground coal mines. The stability of the tramway system in a mine is influenced by many factors, such as geological and mining conditions. In order to evaluate the stability of tramway tracks in underground coal mines, monitoring activities are carried out periodically. This activity is to provide accurate data on the current status of the rail system, early detection of displacement and deformation of the system. This paper presents the results of monitoring tram tracks in underground coal mines by the terrestrial laser scanning technology (TLS). The objective of the study are to evaluate the capacity of TLS in monitoring tram tracks in underground coal mines, and to propose a workflow for this activity. The experiment was held at the tramway in the main transport tunnel at the level of -350 m in the Nui Beo underground coal mine. A procedure was proposed, including the planning, collecting data in the field, data processing, and analyzing data. The surveing equipment was used, including: (1) a Topcon GLS 2,000 scanner for the TLS survey, (2) Digital leveling for measuring the elevation of the rails, (3) a tape for measuring the distance between the rails. The measurement of the distance between two railway lines were performed on the TLS point cloud. The comparison between TLS and the tape showed that the maximum difference was less than 3 mm and met the requirements of the monitoring of tram tracks in underground coal mines.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130208890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).10
H. Tran, Truong Hung Trieu, N. Nguyen
In the oil and gas exploitation or geo-thermal energy exploitation industries, wellbores can be drilled at great depths where the formation would be hot and saturated. In such case, a large temperature difference between the rock mass and drilling fluid can occur and cannot be ignored. During drilling the wellbores, thermic, hydraulic and mechanical phenomena appear simultaneously and interact with each other within the rock. This study presents the analysis of stress state around the wellbore located in saturated hot rock based on the fully thermo-hydro-mechanical behavior model of the rock mass by the finite element method. Two scenarios involving thermal conditions at the well wall are taken into account, i.e. the drilling fluid temperature is lower or higher than the formation temperature so-called the cases of “cooling” and “heating”, respectively. In this study, the influence of some thermic, hydraulic and initial stress field parameters of the rock mass on the stress state around the wellbore was also clarified. The obtained results showed that, in the cooling case, the well wall may be destabilized by fracture failure while in the heating case this would be collapse failure. The maximum points of tangential and axial stresses appear at the same locations for the two scenarios. In addition, the thermal expansion coefficient, the initial shear stress in the rock mass greatly affect the stress state around the wellbore whilst the permeability of the formation does not influence on the stresses on the well wall but only on the stresses inside the surrounding formation.
{"title":"Analysis of the stress state around wellbores in saturated porothermoelastic rock","authors":"H. Tran, Truong Hung Trieu, N. Nguyen","doi":"10.46326/jmes.2023.64(2).10","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).10","url":null,"abstract":"In the oil and gas exploitation or geo-thermal energy exploitation industries, wellbores can be drilled at great depths where the formation would be hot and saturated. In such case, a large temperature difference between the rock mass and drilling fluid can occur and cannot be ignored. During drilling the wellbores, thermic, hydraulic and mechanical phenomena appear simultaneously and interact with each other within the rock. This study presents the analysis of stress state around the wellbore located in saturated hot rock based on the fully thermo-hydro-mechanical behavior model of the rock mass by the finite element method. Two scenarios involving thermal conditions at the well wall are taken into account, i.e. the drilling fluid temperature is lower or higher than the formation temperature so-called the cases of “cooling” and “heating”, respectively. In this study, the influence of some thermic, hydraulic and initial stress field parameters of the rock mass on the stress state around the wellbore was also clarified. The obtained results showed that, in the cooling case, the well wall may be destabilized by fracture failure while in the heating case this would be collapse failure. The maximum points of tangential and axial stresses appear at the same locations for the two scenarios. In addition, the thermal expansion coefficient, the initial shear stress in the rock mass greatly affect the stress state around the wellbore whilst the permeability of the formation does not influence on the stresses on the well wall but only on the stresses inside the surrounding formation.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128058121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).08
Dong Thanh Khuc, Hang Ha, Phong Duc Bui, Quang Xuan Truong, A. Tran, H. Q. Pham, Trong Dinh Tran, Cong Chi Nguyen, Huong Thi Tran, Anh Van Truong, Minh Hong Thi Tran
Landslides are a natural disasters that frequently occur in the northern mountainous region of Vietnam. This study aims to compare the efectiveness of the Analytical Hierarchy Process (AHP) and Frequency Ratio (FR) modeling in mapping susceptibility to landslides with the support of a Geographic Information System (GIS). The study area is Van Yen district in Yen Bai province, which experiences a high frequency of landslides annually. Ten factors were used as variables in the model, including the lithology map, slope, aspect, plan curvature, profile curvature, topographic wetness index, fault network, river network, road network, and land cover data. The study used a landslide statistical report that including 211 landslide points to create the frequency ratio model, while the pairwise comparison method based on expert opinion was used to establish the weights for the AHP method. The results produced a spatial distribution of landslide susceptibility with five levels: very low, low, moderate, high, and very high. The study used the Area Under the Curve (AUC) to evaluate the performance of both models. The results indicated that the model using the Frequency Ratio method outperformed the Analytical Hierarchy Process model by 4.7% in addition to the similarity between landslide susceptibility maps and past landslide locations.
{"title":"Comparison analytical hierarchy process (AHP) and frequency ratio (FR) method in assessment of landslide susceptibility. A case study in Van Yen district, Yen Bai province","authors":"Dong Thanh Khuc, Hang Ha, Phong Duc Bui, Quang Xuan Truong, A. Tran, H. Q. Pham, Trong Dinh Tran, Cong Chi Nguyen, Huong Thi Tran, Anh Van Truong, Minh Hong Thi Tran","doi":"10.46326/jmes.2023.64(2).08","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).08","url":null,"abstract":"Landslides are a natural disasters that frequently occur in the northern mountainous region of Vietnam. This study aims to compare the efectiveness of the Analytical Hierarchy Process (AHP) and Frequency Ratio (FR) modeling in mapping susceptibility to landslides with the support of a Geographic Information System (GIS). The study area is Van Yen district in Yen Bai province, which experiences a high frequency of landslides annually. Ten factors were used as variables in the model, including the lithology map, slope, aspect, plan curvature, profile curvature, topographic wetness index, fault network, river network, road network, and land cover data. The study used a landslide statistical report that including 211 landslide points to create the frequency ratio model, while the pairwise comparison method based on expert opinion was used to establish the weights for the AHP method. The results produced a spatial distribution of landslide susceptibility with five levels: very low, low, moderate, high, and very high. The study used the Area Under the Curve (AUC) to evaluate the performance of both models. The results indicated that the model using the Frequency Ratio method outperformed the Analytical Hierarchy Process model by 4.7% in addition to the similarity between landslide susceptibility maps and past landslide locations.","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114170369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-02-01DOI: 10.46326/jmes.2023.64(2).01
T. Nguyen, N. D. Dang, Bang Duc Dao
The situation of saltwater intrusion in coastal aquifers in Da Nang city is greatly affected by urban planning, exploitation and water resources use. This article presents research data on hydrogeochemical characteristics and stable isotope composition, thereby determining the origin of groundwater in aquifers then study on saltwater intrusion. The relationship between δ2H and δ18O during rainy season shows that the water in the Holocene aquifer in Da Nang coastal area has isotopic composition similar to regional meteorological water and does not mix with seawater, the main source recharges to the aquifer is rainwater. During dry season, d18O in groundwater is low but d2H is enriched by recharged rainwater from higher attitude area and also affected by exchange with leakage water from landfills. The saline water in this aquifer tends to be washed by rainwater leading to the phenomenon of paleness and the area of salt water in the aquifer is gradually shrinking. These research results are very important in propose a solution for ground water extraction plan and control saltwater intrusion for groundwater
{"title":"Characteristics of hydrochemical and d2H, d18O stable isotopic composition to study saltwater intrusion in coastal aquifers in Danang city","authors":"T. Nguyen, N. D. Dang, Bang Duc Dao","doi":"10.46326/jmes.2023.64(2).01","DOIUrl":"https://doi.org/10.46326/jmes.2023.64(2).01","url":null,"abstract":"The situation of saltwater intrusion in coastal aquifers in Da Nang city is greatly affected by urban planning, exploitation and water resources use. This article presents research data on hydrogeochemical characteristics and stable isotope composition, thereby determining the origin of groundwater in aquifers then study on saltwater intrusion. The relationship between δ2H and δ18O during rainy season shows that the water in the Holocene aquifer in Da Nang coastal area has isotopic composition similar to regional meteorological water and does not mix with seawater, the main source recharges to the aquifer is rainwater. During dry season, d18O in groundwater is low but d2H is enriched by recharged rainwater from higher attitude area and also affected by exchange with leakage water from landfills. The saline water in this aquifer tends to be washed by rainwater leading to the phenomenon of paleness and the area of salt water in the aquifer is gradually shrinking. These research results are very important in propose a solution for ground water extraction plan and control saltwater intrusion for groundwater","PeriodicalId":170167,"journal":{"name":"Journal of Mining and Earth Sciences","volume":"233 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132469346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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