bluuebunny/crossref_metadata_2025 huggingface dataset:
Real-time operating decision support system for reservoir operation using weather forecast and a hydrological model
Authors: Ha Thuy Van , Ha Tuan Ngoc , Nguyen Khoat Duc ,   Hanoi University of Mining and Geology, Hanoi, Vietnam  Kyushu Electric Power Co., Inc., Fukuoka, Japan
Published: May 2024

This paper presents the application of a real-time decision support system (DSS) for power generation and flood control at the Thac Xang hydropower plant in Lang Son province, Vietnam. The DSS consists of three key components: real-time operation and visualization, forecast, and optimized decision modules. The real-time operation and visualization module provides operators with a graphical interface that displays real-time data on the plant's status, such as water levels, reservoir levels, and power output. The weather forecasting module provides information about future precipitation. This information is used as input data for the inflow forecasting model. The real-time computing module takes into account current conditions, such as the water level in the reservoir to compute relevant variables such as current inflow rate or outflow rates from the reservoir. The simulation module is used to test different operating scenarios taking current and future inflow rates into account. This helps the plant operators to understand the impact of their decisions on the plant's performance. The simulation module can also be used to identify potential problems and develop contingency plans. Therefore, a mathematical model is developed. Particularly, this model uses real-time information of dams. The main objective is to maximize economic value over the time horizon by producing electricity when it is most valuable. An approach of a simulated annealing algorithm is used to solve this model. We also present a decision support software tool for small hydropower systems that provide hydropower equipment operators with the information required to optimize the dam's performance in terms of power efficiency and effectiveness.
Evaluation of soil surface moisture in Dak Nong province, Vietnam by Sentinel-1 radar image
Authors: Vu Thao Phuong Thi , Nguyen Phi Quoc , Do Cuong Cao ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

This study focuses on monitoring the variation of surface soil moisture (0-1 cm) and ground soil moisture (0÷1 m) in the soil in Dak Nong province using Sentinel-1 radar images received in December 2017. Active radar signals utilized in this method were sent and received using short wave pulses. The intensity of the received signal is compared to determine the scattering coefficient of the surface. The most common imaging constructs of active shortwave are Synthetic Aperture Radar (SAR), which transmits a series of pulses that pass through a radar antenna. Soil moisture is calculated by measuring electromagnetic radiation in the wavelength range from 0,5÷100 cm based on the contrast between the dielectric properties of water (~80) and soil particles (<4). With increasing humidity, the dielectric constant of the water mixture increases, this change can be detected by radar sensors. The results of moisture estimation by satellite images are checked by the results of field sampling and laboratory analysis. Radar remote sensing technique has demonstrated the ability to estimate soil moisture on the principle of correlating with actual measured data. The return scattering value of the soil consists of two components: the former is the feedback scattering value of the raw soil; while the latter is the feedback scattering value of the vegetation cover. It is recommended that this technology should be applied to territories with complex, difficult-to-access terrains and few meteorological monitoring stations.
Determining the size and shape of a dimension stone block under consideration on the spatial relationship of joint sets
Authors: . Viet Van Pham , . Tuan Anh Nguyen , . Bao Dinh Tran , . Hoa Thu Thi Le , . Thao Qui Le , Nguyen Thanh Tuan , Phan Viet Hong ,   Hanoi University of Mining and Geology, Hanoi, Vietnam  Binh Duong Department of Industry and Trade, Binh Duong, Vietnam  Innovations for Sustainable and Responsible Mining (ISRM) Research Group, HUMG, Hanoi, Vietnam
Published: May 2024

Dimension stone not only represents the quality, including strength, color, and polish indexes but also shows the size and shape to obtain standard requirements for the processing plant. One of the issues affecting the size and block recovery ratio is discontinuities inside the stone, dividing into specific sizes and shapes. Therefore, the paper shows a relationship among three main joint sets, existing in the quarries, influencing the size and shape of a stone block generated by intersections of these joint sets. Each joint set is characterized by dip, dip direction, and spacings. Modelling discontinuities from three main joint sets generated a stone block with a specific size and shape. The paper carried out at stone quarries in Phu Yen, Binh Dinh, and Khanh Hoa Provinces. The results showed that when changing one of the geometry parameters of these joint sets, the size, and shape will be correspondingly changed. These sizes and shapes depend on the spatial intersection of these joint sets. In addition, the recovery ratio of each block for processing was calculated regarding its shape to assess which quarries have a good relationship with joint sets. From the minimum size for the processing plant is a rectangular parallelepiped of 0.4 m3, the minimum spacing of joints in a set was defined to satisfy such requirements. This contributes to showing which quarries have a favorable condition on stone size and shape the plant requires. From this, the spacings are equal or more than the minimum spacing in each joint set for quarries determined to calculate the reverse of the rectangular parallelepiped of equal or more than 0.4 m3.
Study of the urban heat island intensity using Landsat 8 in Da Nang in 2020
Authors: Trinh Thu Hoai Thi , Bui Tham Hong Thi ,   Hanoi University of Natural Resources and Environment, Hanoi, Vietnam
Published: May 2024

Monitoring spatiotemporal changes in land surface temperature in metropolitan areas is important to obtain the necessary information about environmental conditions and promote sustainable cities. Da Nang is a big city and is considered one of the tourist centers of Vietnam. Economic development and population growth lead to the expansion of urban land there. That affects the environment, especially resulting in the increase in surface temperature of the core city compared to the surrounding areas. The application of remote sensing data and techniques using thermal sensors for the estimation of land surface temperature and the formation of urban heat islands. This research aims to determine land surface temperature (LST) values and urban heat island (UHI) intensity distribution using Landsat 8 images. UHI is calculated in two steps: first, LST is calculated, and then the temperature threshold for UHI and none UHI is determined by the mean and standard deviation statistics of LST in the study area. To compute the LST, two levels of data must be processed: the NIR and RED bands from level 1 and the thermal band from level 2. The results showed the temperature in Da Nang varies from 15.7÷46.8 0C, with a significant regional temperature variance. The areas with high vegetation index had low temperatures while areas with low vegetation index had high temperatures. Non-UHI areas are present in areas with dense vegetation, dominated by Hoa Vang district and Son Tra peninsula. UHI is found in areas with temperatures more than or equal to 34.2 0C. The urban heat island has been taken play in the core of Da Nang, where the densely populated areas, industrial zones, airports, and landfill are located.
Building a program to automatically classify point cloud data
Authors: . Quy Ngoc Bui , Le Hien Dinh , . Hiep Van Pham , Vu Tung Son , . Quan Anh Duong , Tran Trang Thu Thi ,   Hanoi University of Mining and Geology, Vietnam
  Research and Development of Geospatial Data Management and Analysis Techniques
 (GMA), Hanoi University of Mining and Geology, Vietnam
  Natural Resources and Environment One Member Co., Ltd, Hanoi, Vietnam
  GeoPro Ltd, Hanoi, Vietnam
Published: May 2024

Along with cartography science and technology development, data acquisition through aeronautical laser scanning systems has been developing. This is an essential and detailed data source for database construction, mapping, and city 3D modeling,... City 3D modeling requires processing many types of data, at which point cloud data processing and classification play an essential role in creating input data sources for the model. However, the processing and classification of point cloud data mainly depend on commercial software with very high costs; moreover, the algorithms and parameters of commercial software are locked. That makes it impossible for the user to intervene to improve product accuracy. Therefore, building a program to automatically classify point cloud data into different geographical objects helps us master data processing technology for creating 3D models. It makes an important contribution to building and developing smart cities. The article introduces the step-by-step classification of LiDAR point cloud data and the process of automatically building a program to classify point cloud data based on Visual Studio.Net language. The result is a bilingual program automatically classifying point cloud data (Vietnamese - English). The program can read and fully deploy algorithms to process LiDAR point cloud data containing information with four color bands (red, green, blue, and near-infrared). The primary processing is based on proposed classification steps and thresholds for point cloud data classification into eight feature classes, including hydrology, solar land, traffic, low plants, medium plants, high plants, houses, and other objects, to establish 3D city models.
Detecting outliers in GNSS position time series using machine learning techniques
Authors: Nguyen Huy Dinh , Tran Trong Dinh ,   Hanoi University of Civil Engineering, Hanoi, Vietnam
Published: May 2024

The Global Navigation Satellite System (GNSS) position time series is applied in studies that require high-precision positioning, such as monitoring tectonic movements and Earth deformation. Outliers in GNSS position time series can significantly impact the accuracy of station positioning and movement parameters, leading to distorted data analysis outcomes. This study investigates the effectiveness of three machine learning techniques, including-Isolation Forest, One-Class Support Vector Machines (O-C SVM), and Local Outlier Factor (LOF) for outlier detection in GNSS position time series, with a specific focus on the SYNT model where outliers account for a substantial proportion (15%). Through comprehensive analysis, our results highlight the exceptional performance of the Isolation Forest method. It demonstrates remarkable accuracy in identifying outliers, effectively detecting the majority of them, and achieving an area under the ROC curve close to 1. In contrast, the LOF method performs less effectively in outlier detection, while the O-C SVM method displays relatively higher accuracy in identifying normal data points. These findings emphasize the significant advantages of leveraging machine learning approaches in processing continuous GNSS measurement data. By effectively identifying and handling outliers, these techniques enhance the accuracy and reliability of data analysis in GNSS position time series, ultimately establishing their superiority in the field of data analysis.
Research solutions and completion of unloading operations with Nitrogen lifting method in the oil production wells with dual string at Pearl oil field,
Authors: Le Duyen Quang , Pham Trung Van , Nguyen Chinh Duc , Le Hoa Dac , Nguyen Thanh Van , Ngo Nam Tuan ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
  Project Block 0<0, PVEP, PVN, Vietnam
  Petrovietnam, Camau Fertilizer Joint Stock Company, Camau, Vietnam
Published: May 2024

Rehabilitation for multistage production wells is relatively complicated, especially for wells because the design is not really suitable in the well development stage after a long time of prodution. The production wells at the Pearl rig are currently having problems recovering the permeability of the reservoir. For the purpose of increasing the exploitation flow of the well and restoring the output for wells with long service life, the process of calling the product flow after the end of well drilling and well repair campaigns is extremely difficult. Plays a key role in the exploitation of oil and gas wells. However, some current calling methods are not suitable, costly and have low efficiency due to a number of reasons such as technical errors when completing wells, as well as the initial time when investors had different methods. The application method is not suitable, causing the exploitation well to bring low efficiency. Therefore, the research team investigated the production modes and then proposed production recovery scenarios for the wells using liquid nitrogen combined with the existing techniques at the rig that are suitable for the circumstances in Vietnam. Mining rigs have a tight workspace design. In addition, the solution helps to reduce the cost as well as the complexity of the working process at the marine works, bringing both economic and technical efficiency to the restoration of degraded wells. About the catch, without using other stream calling methods.
Fault seal analysis for VS area, block 16 -1/15, Cuu Long Basin, Viet Nam
Authors: Nguyen Hung Viet , Pham Son Xuan , Nguyen Tam Minh , Doan Quang Dinh , Nguyen Thanh Van , Lai Lap Quoc ,   PVEP-ITC, Hanoi, Vietnam
  Vietsopetro, Baria - Vungtau, Vietnam
  East Sea Stars, Hochiminh City, Vietnam
Published: May 2024

Fault-bound traps represent an important class of hydrocarbon-bearing structure. Whether a fault can seal hydrocarbons on a geological timescale may be controlled by one or more of three conditions: (1) sealing due to lithological juxtaposition, where reservoir rock is juxtaposed against sealing rock across the fault; (2) sealing by the fault damage zone, which forms a barrier composed of low-permeability clay within the fault zone and (3) the tectonic activity of the fault, as during faulting, hydrocarbon accumulations can be destroyed and leakage along the fault zone. This research employs an indirect method to establish a correlation between pressure and the sealing properties on fault surfaces, such as the SGR (Shale Gouge Ratio), across various formations under the same geological conditions from all fields within the region and around the world. This aids in assessing the sealing potential of the faults. Evaluate the fault seal capacity according to 3D model for the structures in Oligocene D, Oligocene C and Lower Miocene sediments to serve the assessment hydrocarbon potential in VS area and reduce the risk for further exploration - appraisal work in block 16-1/15, Cuu Long basin. Geology, seismic and petrophysical data were used to construct 3D structural frameworks, lithology model and Vclay model. Parameters such as fault throw, Vshale, lithology, bed thickness, burial depth history, fluid density and pressures, ect. are incorporated into fault seal analysis and also estimate the maximum hydrocarbon column height can be held by each fault in study area, therefore helping to assess the hydrocarbon potential in undrilled structures in VS area.
Selecting a suitable model for the closure of building material stone mines for sustainable development in Binh Duong, Vietnam
Authors: Phan Viet Hong , . Nam Xuan Bui , . Tuoc Ngoc Do , . Hoan Ngoc Do ,   Binh Duong Department of Industry and Trade, Vietnam  Hanoi University of Mining and Geology, Hanoi, Vietnam  Innovations for Sustainable and Responsible Mining (ISRM) Group, Hanoi, Vietnam  Institute of Mining Science and Technology (IMSAT), Hanoi, Vietnam
Published: May 2024

The closure and environmental restoration of quarry sites for construction material extraction in Vietnam in general and in Binh Duong province in particular still face various challenges that have not brought significant and sustainable development opportunities. The study aims to select a suitable model for the closure of building material stone mines to contribute to sustainable development in Binh Duong. Based on the survey of economic-social characteristics, environmental safety, and development policies of the construction material quarrying area in Binh Duong province, this study applied SMART methods to determine specific objectives as a basis for constructing measurable, achievable, relevant, and time-bound criteria for evaluating quarry closure options. The simple additive weighting method was employed to calculate the value of each option, which was optimized through the analytic hierarchy process for clear criteria or the fuzzy analytic hierarchy process method for dealing with uncertain or ambiguous criteria, to determine the reasonable option for mine closure. For criteria that was ambiguous or unclear, the fuzzy analytic hierarchy process was employed to establish reasonable options for quarry closure. Synthesizing the research results for two closure options after extraction for a typical quarrying area in Binh Duong, the study selected a viable option that effectively utilized land resources, created new residential areas for the local population, and utilized the quarry pit for solar energy extraction, which is a clean energy source that brings economic and social benefits to the region. This approach could serve as a valuable reference for mine closure decision-making processes in Vietnam and other countries facing similar challenges in sustainable development.
Improving the efficiency of the coal-cutting process by combining cutting teeth on the drum of the coal-cutting machine used in underground coal mining
Authors: Nguyen Linh Khac , Pham Tien Van ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

Nowadays, coal mining is primarily carried out by underground method. The shearer is the main equipment used in underground coal mining in developed mining countries and it is gradually applied in underground coal mines in Viet Nam. With coal-cutting machines, using the cutting drum is applied mainly because of its simple structure, high productivity, and reliability. However, during the coal-cutting process, the fine coal content of about 40÷50% of the total mining output causes dust generation as well as energy consumption because the coal is cut too small. According to previous studies, this problem is solved by increasing the thickness of the slices, which is achieved by using larger drums with large cutting teeth, and in combination with increased speed movement of the stage machine. This increases machine size, large investment costs and reduces machine flexibility due to the tight space of mining areas. Through the research of previous authors, it is possible to increase the cross-sectional area of the slices by forming slices in pairs and groups, and at the same time enhance the failure by tensile stress instead of mostly compressive stress. In addition, the overlap of stresses around the slice, when using the coal-cutting teeth group, also reduces the cutting force on the cutting teeth. In this study, a new solution is proposed to increase the height of the cutting teeth and the width of the cutting step without increasing the local load acting on the cutting teeth by combining the cutting teeth in groups thereby reducing dust, increasing the particle size of the cutting teeth coal, reducing specific energy and increasing cutting capacity of the coal cutting machine.
Build land price WebGIS with ArcGIS online and ArcGIS API
Authors: . Cong The Nguyen , . Mien Xuan Tran , . Thoa Kim Thi Pham ,   Faculty of Geomatics and Land Administration, Hanoi University of Mining and Geology, Hanoi, Vietnam  Land Management and Cadastral Technology for Sustainable Development (MTS), Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

Building and completing the land price database contributes to completing the land database, promoting digital transformation, improving the effectiveness and efficiency of the state management of land, while increasing transparency in deciding land prices, increasing interconnectivity and modernizing public land services. However, nationwide land price data has not yet been formed, studied. Reserach projects of the Ministry of Natural Resources and Environment are still mainly focusing on solving land valuation problems and building a land database. In the world, the construction of an online land price information system has been implemented on the basis of WebGIS technology and achieved many good results. This article introduces the process and experimental results of building a land price database in Dong Cuong commune, Yen Lac district, Vinh Phuc province. Tools used in this study include ArcGIS Online, ArcGIS API, Microsoft SQL SERVER; Spatial land price data is built from cadastral spatial data after standardization according to Circular No. 05/2017/TT-BTNMT of the Ministry of Natural Resources and Environment. The experimental results of building a Land Information System identify 4 groups of users: Guests, Members, Data Management and System Administrator. The land price information system is designed in the form of a Web-app, installed on the website with the address: https://giadat.gis-humg.com.
Evaluation of landslides, accretion circumstance and riverbank slope stability analyses in the Mekong Delta
Authors: Bui Hau Vinh , Tran Tuan Quang ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

This study presents the current situation of landslides and accretion on the Tien and Hau riverbanks in the Mekong Delta over time. Simultaneously, the riverbank slope stability was assessed and showed some related effects. Statistical methods, combined with field surveys and GEOSlope analysis, were used to assess the circumstances of landslides and accretion. Results show that the most landslides have occurred in the An Giang and Dong Thap areas. In the prior 2015 period, 23 and 7 riverbank sections with frequent landslides were excavated and inventoried on the Tien and Hau rivers, respectively. Meanwhile, 28 and 9 sections where accretion occurred during this period were inventoried on the Tien and Hau riverbanks, respectively. Since 2015, 248 locations of landslides and accretion occurring in the area have been investigated. The study also indicates that the displacement of active tectonic faults and instability of riverbank slopes have been demonstrated and complemented the landslide causes in the area. These results are intended to warn and help local authorities to promptly take positive measures to prevent and orient appropriate socio-economic development for the region.
Assessment of Geoheritage of Geosites in Trang An –Ninh Binh area
Authors: . Binh Van Phan , Tran Thanh Duc , . Thanh Xuan Ngo , . Dao Anh Vu , . Hiep Huu Nguyen , . Hau Vinh Bui , . Hung Quoc Nguyen , Ngo. Chi Kim Thi , Bui Hien Thu Thi ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
  Key research group "Tectonics and Geodynamics for Geo-resources, Environment and Sustainable Development", Hanoi University of Mining and Geology, Hanoi, Vietnam
  University of Social Sciences and Humanities, Hanoi, Vietnam
Published: May 2024

Trang An - Ninh Binh is a captivating tourist destination, both for domestic and international travelers, renowned for its abundant geological, geomorphological, and ecological features, as well as its rich cultural and historical significance. It was designated as a UNESCO World Cultural and Natural Heritage site in 2014. With the objective of fostering tourism development by harnessing the geological heritage and formulating conservation strategies for geological heritage sites, the present endeavor focuses on assessing the geoheritage values and potential of seven distinct geosites within the Trang An area. These geosites include Sang Cave, Dark Cave, Nau Ruou Cave, Dia Linh Cave, Tran Cave, Dot Cave, and Ba Giot Cave. In accordance with the global framework for geological world heritage, the findings reveal that these seven geosites can be classified into three categories of geological sites: Type B - Geomorphology, Type D - Stone, and Type I - Tectonic. Employing a set of criteria to evaluate the value of geological heritage, encompassing scientific, educational, and touristic significance, it becomes evident that Trang An - Ninh Binh possesses considerable scientific and educational value, and its potential for geotourism development is highly promising. Additionally, the tourism potential of these heritage sites is vividly expressed through their symbolic and highly representative features, which characterize the landscape of Trang An - Ninh Binh. The research results provide an invaluable scientific foundation for local management in the pursuit of sustainable conservation and economic development of tourism in the region.
Solutions to increase the C-2P well production performance at X oil field, Block 09-2
Authors: Do Khoan Duy , Nguyen Thinh Van ,   PetroVietnam Exploration Production Corporation, Hanoi, Vietnam
  Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

The well C-2P had its first oil production in July 2008, the initial production rate is 3,000 barrels/day. Due to the reservoir pressure depletion in 2017-2018, the well faced difficulties in kicking off to open the well for production. In November 2018, when the C-5PST2 well was put into production, the C-2P well was not produced by natural flowing. The kicking off has been attempted many times but the well still won't flow. The main reason the well couldn’t flow is due to low reservoir pressure which has not enough energy to push all the fluid in the well to the surface after each well shutdown. The flow assurance study shows, at the reservoir pressure of 3,000 Psi, and tubing head pressure of 950 Psi, the well can’t flow naturally. In addition, with the reservoir pressure of 3,000 psia and applying the gaslift injection rate of 1.0 MMscf/d, injection point at 3,030 mTVD, the well flowed. The continuous gaslift pump helps maintain the well's production in case the reservoir pressure drops even lower to 2,000 psi, and at the same time, optimizing the gaslift pump flow helps to increase the well production by 100-300 barrels of oil/day. When the reservoir pressure drops lower, it is necessary to lower the gaslift valve deeper to continue kicking off the well and maintain the well production performance. On the other hand, due to the lack of a gaslift valve for the original design of C-2P well so it's necessary to have gaslift tubing pack off in order to bring the well back to production, maintain stability and improve production. This paper, therefore, presents the results of the research on the solution to increase the production output of the C-2P well located in X oil field used gaslift valve combining with the tubing pack off. Results of the research on the application of solution show that the well's production output has increased significantly (0.354 million barrels) in the first year of applying the solution.
Developing a Saturation Height Function (SHF) for the classified Hydraulic Flow Unit, a case study from the Middle Miocene Carbonate reservoir in the Song Hong Basin, Vietnam
Authors: Nguyen Dung Trung , Ha Man Quang , Nguyen Viet Hong , Phan Huong Thien , Hoang Cu Minh , Truong Hoa Khac ,   Petrovietnam Exploration Production Corporation, Hanoi, Vietnam
  Schlumberger Vietnam, Hochiminh, Vietnam
  Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

The Middle Miocene carbonate is the main gas bearing reservoir in the southern part of the Song Hong basin. Carbonate reservoirs present challenges for engineers and geologists to characterize because of their complexity due to depositional and diagenetic processes. The log based calculated water saturation Sw for this complex carbonate reservoir bears a lot of uncertainties due to its heterogeneity that strongly affects to m and n values in the water saturation equation. As the calculated Sw strongly affects the Hydrocarbon Initially In Place (HIIP) estimation, the production performance prediction, etc., the alternative method using the Saturation Height Function (SHF) based on the capillary pressure was introduced. The SHF building process uses the combination of the result of HFU classification and permeability prediction given by machine learning methods, which have become a very useful tool for complex reservoir characterization such as carbonate reservoir for decades. Our obtained results allowed us to subdivide the carbonate reservoir into 5 Hydraulic Flow Unit (HFU) by using unsupervised machine learning methods, and then the capillary pressure (Pc) curves were classified and a proper saturation-height function using Skelt Harrison equation was assigned to individual HFU after testing with common SHF equations. The HFU number for each individual point was predicted based on the log data measured along the borehole using the supervised machine learning techniques while the Sw was calculated using the chosen SHF model and the FWL defined on log curves and pressure data from RCI measurement. The Sw computed from the SHF model is reliable and can be used for water saturation estimation for the whole field for known FWL and predicted HFU numbers.
Researching and applying open-source WebGIS technology to build national-standard vector geographic database management software
Authors: Phan Yen Quoc ,   Le Quy Don Technical University, Hanoi, Vietnam
Published: May 2024

Geographical database management is a crucial component of spatial data infrastructures (SDIs) and is used by government organizations in provinces, regions, and countries. It plays an important role, especially during the 4.0 technology revolution and digital transformation to build e-government and digital government. A complete and scientific management of geographical databases is the most crucial core foundation of a system. The article applies open-source WebGIS technologies such as Geoserver map server, PostGIS data management software, Python programming language, Vue, and Openlayers map library to build spatial data management software. Spatial data is mainly in vector form, built according to national geographic database standards (QCVN 42: 2020/BTNMT). The system has main functional groups such as user account authorization and user groups; and geographic database management, including seven groups: borders, geodesy, population, topography, traffic, surface cover, and hydrology. In addition, the administration of some thematic classes such as drafting plans, managing equipment and units, etc., are performed. The software system is built in a service-oriented manner, serving as the core foundation to facilitate the development of many geo-portal applications.
Foraminifera in the Holocene sediments at the shallow sea from Phu Loc (Thua Thien Hue) to Hoi An (Quang Nam) (0÷60 m of water depth)
Authors: Ngo Chi Kim Thi , Mai Lac Van , Nguyen Hieu Huu , Nguyen Quyen Minh , Phan Binh Van , Bui Hien Thu Thi ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
  Vietnam Union of Geological Sciences, Hanoi, Vietnam
  Center for Planning - Investigation of Northern Marine Resources and Environment, Hanoi, Vietnam
  Geological Division for Radioactive and Rare Elements, Hanoi, Vietnam
Published: May 2024

The shallow sea (0÷60 m of water depth) from Phu Loc (Thua Thien Hue) to Hoi An (Quang Nam) belongs to the internal shelf in Central Vietnam. This is quite a good geological structure for the land-sea interaction study, especially during the Holocene. Therefore, it is necessary to study the geological history of the area during the Holocene period. Foraminifera is the subject of geological studies to solve the environmental problems of sedimentary, stratigraphic, and paleogeography. However, at present, the research documents on Foraminifera in the sediments in Vietnam in general as well as in the research area in particular are still very modest. This paper presents research results of Foraminifera fauna in Holocene sediments from Phu Loc (Thua Thien Hue) to Hoi An (Quang Nam) (0÷60 m of water depth). 93 species, belonging to 48 genera, 28 families and 5 suborders Foraminifera have been identified based on the analysis of 59 available samples. Miliolina Delage et Hérouard, 1896 has 06 families, 18 genera and 40 species; Rotaliina Delage et Hérouard, 1896 has 12 families, 15 genera and 29 species; Textulariina Delage et Hérouard, 1896 has 03 families, 05 genera and 07 species; Lagenina Delage et Hérouard, 1896 has 03 families, 04 genera and 07 species; Globigerinina Delage et Hérouard, 1896 has 04 families, 06 genera and 10 species. The quality of the benthonic Foraminifers is dominant, clearly showing the geological environment of the shallow sea near shore, where the hydrodynamic regime is high and the salt concentration is not stable.
Cobalt in the regolith upon Nui Nua ultramafic Massif
Authors: Nguyen Thanh Trung , Nguyen Giang Khac , Nguyen Trong Huu , Vo Chinh Cong Thi , Nguyen Hai Manh ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
  Vang Tat Mineral Exploitation Company Limited, Vietnam
Published: May 2024

Cobalt (Co) Metal plays an increasingly important role in the battery and engine manufacturing industry for electric cars. Previously most of Co was mined as by-product in copper ore deposits in Central Africa. Recently, the proportion of Co extracted from other sources such as weathering-derived mines on ultramafic rocks is increasing. In Vietnam, Cobalt has been discovered in Cu-Ni ore deposits in the Northeast and Northwest Regions. The literature shows that cobalt is found in small amounts in ultramafic rocks. During the weathering process of ultramafic rocks, Co ions will be priority adsorbed in the hydroxide colloids of Mn and Fe (goethite and asbolan). In the regolith upon Nui Nua Masif, Ni content increased dramatically (several times) from 0.19% in bedrocks up to 1% in some locations, while cobalt content just increased only slightly (from 0.02% in bedrock to 0.05 regolith, rarely up to 0.1%). The results of the previous analysis of weathered crust samples of ultramafic rocks of Nui Nua massif by several authors show that, unlike Ni which is presented in both silicate minerals and Fe-Mn oxide/hydroxide, cobalt ions tend to be concentrated in Fe-Mn oxides/hydroxides. Our SEM analyses combined with EDS show some remarkable results: the Co content in some specific minerals is quite high from 1.12÷4.67% (denominator). This is only a preliminary result and it is necessary to conduct more work to further detailed studies defining the Co potential in weathering products of ultramafic rocks of Nui Nua massif as well as in the areas where other ultramafic rocks are developed. Recently, research confirmed that there is a significant Co-Ni occurrence discovered in Mau Lam Valley (Southwest of Nui Nua Massif).
Unconfined compressive strength assessment of soil-cement mixtures in Hai Duong city
Authors: Do Thang Hong , Nguyen Phong Van , Nguyen Hung Van ,   DAVICO.JSC, Hai Duong, Vietnam
  Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

The unconfined compressive strength (qu) of the soil-cement mixture (S-CM) depends on many factors, in which the soil type and the cement content (%CM) are very important factors. The soil type determines the fine particle content and affects the effectiveness of soil-cement mixture. Meanwhile, %CM has a direct influence on the qu of the S-CM. The cost of foundation treatment methods for small and medium-sized constructions depends on the reasonable cement content. This paper presents the unconfined compressive strength of S-CM for five common cohesive soils in Hai Duong city (soft clay, soft clayey sand, soft sandy clay, clayey sand mud, and sandy clay mud) with four cement contents (7%, 10%, 15%, and 20%). The research results show that the clayey sand (mbQ21-2hh) has the highest improvement efficiency compared to other soils, i.e., soft sandy clay (abQ23tb), soft clay (mQ21-2hh), sandy clay mud (mbQ21-2hh), and clayey sand mud (amQ21-2hh). The clay content has a great influence on the qu of S-CM. With the required value of qu28 = (8.0÷10.0) kG/cm2 (at 28 curing days), the reasonable cement content (% CM) is varied from 8% to 13% for soft sandy clay (abQ23tb), soft clay (mQ21-2hh), sandy clay mud (mbQ21-2hh), and clayey sand mud (amQ21-2hh); with the same value of qu28, the reasonable %CM is from 7.5 to 9.0% for clayey sand (mbQ21-2hh). The results are the scientific basis for recommending a reasonable %CM for each type of soil when designing to reinforce the foundation with soil-cement columns in Hai Duong city.
Twin-tunnelling: Case studies in clay
Authors: Divall Sam , Goodey Richard James , . Michael. C. R. Davies , Le Binh Thanh , Nguyen Tra Thu Thi ,   Department of Engineering, School of Science < Technology (SST), University of London, London, United Kingdom.
  A-squared Studio Engineers Ltd, London, United Kingdom.
  School of Engineering and Informatics, University of Sussex, Brighton, United Kingdom.
  Institute of Civil Engineering, Ho Chi Minh City University of Transport, Hochiminh, Vietnam.
Published: May 2024

New developments in the theory and practice of tunnel construction are essential for the industry to progress but it is the relationship between these two areas that is equally as important. Tunnelling practice has greatly benefited from laboratory research; specifically, centrifuge modelling linked with field measurements. The wide body of work on the construction of single tunnels has led to the identification of parameters and techniques that are widely accepted for predicting and assessing the magnitude and extent of tunnelling ground movements. However, the usage of twin tunnels in urban areas for transportation purposes have increased and better understanding on the associated ground displacements are required. This paper firstly provides background to ground displacements due to single tunnel, twin tunnel constructions and common prediction methods used in practice. Then, it introduces recent technological advancements in centrifuge modelling, applied to the complex geotechnical events of twin-tunnelling, that has led to further insight. The tunnelling induced ground displacements obtained from twenty four case studies in clay around the world and eighteen centrifuge tests are presented for further analyses. From that, a comparison between the recent theories of proximity-dependent tunnelling-induced ground movements with case histories has been carried out to establish their validity and limitations. Published field measurements have been reanalysed taking into account newly discovered relationships between the tunnels’ proximity and the magnitude and extent of ground movements, reflected via volume loss and the settlement trough width, respectively. The applicability to field measurements of the additional volume loss prediction method (derived from consideration of the experiment work) for tunnelling in clay is assessed.
Data processing in blast-induced ground vibration measurement issue with Kalman filter
Authors: Dao Hieu , Pham Loan Thanh Thi ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
Published: May 2024

Measurement data processing plays an important role in acquisition systems. Completely eliminating the error caused by noise is a difficult issue because correct data exists in noise. Besides, it is impossible to distinguish them clearly. For this reason, solutions to process and standardize data are always applied in the condition of paying close attention to the peculiarity and specific properties of the measured object and the factors affecting it. Blast-induced Ground Vibration wave data is one of the extremely important information in mining operations. It is used to evaluate the impact of the blasting on construction. Besides, it presents the efficiency of explosives as well as of the blasting and mining operation in general. For many particular cases, the physical and mechanical properties of the object to be broken (geological structure, physical and mechanical properties of the rock in the blasting area) are relatively image by knowing its waves. Furthermore, the parameters of the next blasting are also improved based on this data. Due to its important role, the requirement for automatic and highly accurate recording of blast-induced ground vibration data is an urgent issue in mining operations in Vietnam. In this paper, solutions to apply the Kalman filter to handle ground vibration wave data due to blasting were introduced. The work is done based on considering the properties and factors affecting the amplitude, frequency, and characteristics of ground vibration waves. Data is taken directly from the sensor without any processing. Therefore, it carries a lot of noise from many different causes such as the sensor structure, gravity, rock structure, the other sources of vibration at the same time, etc. The used sensor is a product of Nation Instrument (NI). The content of the article is the result of researching and building an automatic blast-induced ground vibration wave measuring device, which will be applied in the field of mining and quarrying in Vietnam.
Effect of pore water chemistry on the ring shear behavior and the rate dependency of residual strength
Authors: Nguyen Duong Thanh , Suzuki Motoyuki , Nguyen Hai Van , Nguyen Nu Thi ,   Hanoi University of Mining and Geology, Hanoi, Vietnam
  Yamaguchi University, Yamaguchi, Japan
  MienTrung University of Civil Engineering, Phu Yen, Vietnam
Published: May 2024

The rate dependency of residual strength plays an important role in the selection of residual strength parameters to design the remediation works for reactivated landslides. In the literature, it is shown that the rate dependency of residual strength depends on some factors such as types of soil, range of shear rates, range of effective normal stresses, and pore water chemistry. Recently, the effect of pore water chemistry on the rate dependency of residual strength soil has been examined. However, the ring shear behavior and the rate dependency of residual strength of soil having different pore fluids should be more evaluated. In this study, the effect of the pore fluids of distilled water and 1 M NaCl on the rate dependency of residual strength of kaolin clay was investigated in the Bishop ring shear apparatus. The ring shear tests were conducted at different shearing rates from 0.02 mm/min to 20 mm/min under the effective normal stress of 98 kPa. The research results showed that the pore fluid chemistry affected the shear displacement required to reach the peak strength, the vertical displacement, and the peak strength of kaolin clay. These parameters also exhibited rate dependency, especially at the fast shear rates. The research also indicated that the pore fluid chemistry had a significant effect on the rate dependency of residual strength. Accordingly, the rate dependency of residual strength of kaolin mixed with distilled water showed a positive tendency while that of kaolin with 1 M NaCl as the pore fluid was the neutral tendency.
Geological setting of the Phu Khanh Basin based on updated geological-geophysical data
Authors: Hoang Long Van , Bui Hoang Huy , Nguyen Tuan Quang , Ngo Anh Van Thi , Mai Dam Hoang , Nguyen Lan Tuyet Thi , Phung Lan Phuong Thi , Ho Thanh Thi , Tran Huong Thi ,   Vietnam Petroleum Institute, Hanoi, Vietnam
  VPI-Lab, Vietnam Petroleum Institute, Hanoi, Vietnam
Published: May 2024

The Phu Khanh Basin is a Tertiary sedimentary basin located in deep a water area adjacent to the continental shelf of Central Vietnam, which has been begun to form since the Eocene(?)/Oligocene to the Quaternary. This area has previously only been briefly studied based on satellite magnetic, gravity data and some 2D multichannel seismic lines. In this article, the authors present the most recently interpreted and merged gravity data to update the research results on geological structure, tectonics and the history of geological evolution of the Phu Khanh Basin, which are considered significant contributions for hydrocarbon exploration campaigns in the future. Our new results show that mechanism of the the Phu Khanh Basin formation was started by a rifting process with most of it located in the central basin, controlled by four main fault systems, including the NW - NE system, the NE - SW system, sub-meridian system and less active is the sub-latitude system. The evolution of the basin has undergone through four main phases of different tectonic deformation, which are characterized by its typical geodynamic regimes and tectonic activities. These evolutionary phases can be briefly described as follows: (i) Paleocene peneplanation phase, (ii) The active rifting phase in Eocene/Oligocene-Early Miocene, (iii) The Middle Miocene thermal subsidence phase and finally (iv) The Late Miocene-Quaternary shelf building phase. However, the issue of determining the Eocene age at the bottom of the basin has so far remained unclear and elucidated by the lack of deep wells penetrating the deepest region of the basin.
Studying the theoretical basis and advantages and disadvantages of Logistic methods of the total horizontal Gradient
Authors: Nguyen Dat Viet , Kieu Thong Duy , Nguyen Long Ngoc , Vo Quynh Thanh , Nguyen Toan Quoc , Nguyen Hang Thu Thi , Pham Xuan Thanh Thi ,   University of Science, Vietnam National University, Hanoi, Vietnam
  Hanoi University of Mining and Geology, Hanoi, Vietnam
  Union of Geophysics, Hanoi, Vietnam  VNU School of Interdisciplinary Studies, Vietnam National University, Hanoi, Vietnam
Published: May 2024

Edge detection is one of the most important steps in interpretation of magnetic and gravity data. In magnetic and gravity maps, it is difficult to distinguish adjacent sources due to their field superposition. Many different techniques have been used to determine the edges of sources. These techniques are based on vertical or horizontal gradients of magnetic and gravity data or combinations of them, and the edges of the geological structures are determined by maximum, minimum, or zero values in the output maps. One of the most popular techniques is the total horizontal gradient which is based on horizontal gradients of magnetic and gravity data. The capability of the total horizontal gradient technique in mapping the boundaries of deep bodies is very limited when competing with large-amplitude shallow bodies. Some enhanced modifications of the total horizontal gradient technique have been introduced to improve the boundary estimation results. These techniques are based on logistic functions and derivatives of the total horizontal gradient. In this study, we aim to estimate the effectiveness of the logistic filters of the total horizontal gradient. To obtain optimum results, these filters were tested on synthetic gravity and magnetic data and real magnetic data from the Zhurihe region (China). The findings show that the logistic filters can provide more accurate and sharper boundaries without false source edges than the total horizontal gradient. These techniques can determine the edges of shallow and deep structures at the same time. These results demonstrate that the logistic filters are useful tools for the qualitative interpretation of potential field data.