Earth Sciences Research Journal最新文献

{"title":"Mineralogy and Fluid Inclusions of the Cunas Emerald Mine, Maripí, Boyacá, Colombia","authors":"Fernando Helí Romero Ordóñez, A. González-Durán, Javier García-Toloza, Jimmy Rotlewicz Cohen, Carlos Julio Cedeño Ochoa, Holman Rolando Alvarado González, Luis Gabriel Angarita Sarmiento","doi":"10.15446/ESRJ.V25N2.90210","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N2.90210","url":null,"abstract":"The Cunas mine is currently one of the major producers of fine emeralds in Colombia; its emeralds typically display a magnificent green hue, which is highly appreciated in the world market. The mineralization is found in vanadium-rich black shales of the Muzo formation; emeralds occur in pockets within hydrothermal veins and breccias, consisting mostly of calcite, dolomite, albite, quartz, and minor pyrite, parisite-(Ce), and fluorite; hydrothermal alteration is pervasive and dominated by albitization and carbonatization. Emerald-hosted fluid inclusions are highly abundant and remarkably large and complex. Poly-phase inclusions are ubiquitous, occur both in emeralds and gangue minerals, and consist of two daughter crystals (typically halite and calcite or siderite; exceptionally parisite-(Ce)), a liquid brine, a CO2-N2-CH4-rich gas bubble, and occasionally minor liquid CO2. Vapor-rich inclusions were observed in quartz, and two-phase inclusions were identified in calcite and dolomite, thus suggesting a complex fluid evolution. Microthermometry analysis indicates the emerald-forming fluids were trapped at relatively low temperature ≈ 260-340°C and pressure ≈ 875-2400 kbar, with relatively high density —1.03 g/cm³—, and elevated salinity 39% NaCl eq. Wt.; other aqueous components detected include CaCl2, KCl, and FeCl2. Based on these data, we propose the emerald mineralization at the Cunas mine was originated by the mixing of two hydrothermal fluids of different sources; one fluid with high salinity derived from evaporite dissolution, responsible for the albitization of the host rocks; the second is a calcium-rich fluid evolved from connate waters, which was equilibrated by the interaction with calcareous and organic-rich wall rocks. As a result, emerald mineralization took place at structurally favorable sites where fluid mixing was promoted. The described geological and physicochemical features for the Cunas mine, are in agreement with an epigenetic sediment-hosted mineralization —Colombian-type— formed by the circulation and mixing of relatively low-temperature non-magmatic fluids.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44088077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A prediction method of regional water resources carrying capacity based on artificial neural network","authors":"Shi Chaoyang, Zhen Zhang","doi":"10.15446/ESRJ.V25N2.81615","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N2.81615","url":null,"abstract":"To better predict the water resources carrying capacity and guide the social and economic activities, a prediction method of regional water resources carrying capacity is proposed based on an artificial neural network. Zhaozhou County is selected as the research area of water resources carrying capacity prediction, and its natural geographical characteristics, social economy, and water resources situation are explored. According to the regional water resources quantity and utilization characteristics and evaluation emphasis, the evaluation index system of water resources carrying capacity is constructed to evaluate the importance and correlation of water resource carrying capacity. The pressure degree of water resources carrying capacity is divided into five grades. According to the evaluation standard of bearing capacity, the artificial intelligence BP neural network model is constructed. Based on the main impact factors of water resources carrying capacity in this area, the water resources carrying capacity grade is obtained by weight calculation and convergence iteration by using neural network model and influence factor data to realize the prediction of water resources carrying capacity. The research results show that the network model can meet the demand for precision. The prediction results have a high degree of fit with the actual data, indicating that human intelligence can obtain accurate prediction results in water resources carrying capacity prediction.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46323759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentation in reservoirs. Case study: the reservoir of the São Bartolomeu stream, Viçosa, Minas Gerais, Brazil","authors":"Youlia Kamei Saito, L. F. Viana, Í. O. Ferreira, E. Marques","doi":"10.15446/ESRJ.V25N2.79584","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N2.79584","url":null,"abstract":"Sedimentation in bodies of water is a worldwide problem that impairs its navigability and utilization, and, in reservoirs, this process reduces their partial or total storage capacity. Using single-beam bathymetric survey techniques, this study evaluates the silting process in a reservoir section at the Federal University of Viçosa (UFV), located in Viçosa, Minas Gerais, in the Southeast region of Brazil. An analysis of the charts showing the DEM (Digital Elevation Models) and the Elevation x Surface Area x Accumulated Volume for three surveys conducted in 2010, 2012, and 2016 provided the sedimentation rates between these years, as well as the accumulated volume of sediments in the area under analysis for each year. The information we collected shows sediments accumulated in the deepest part of the reservoir in the period between 2010 and 2012. From 2012 to 2016, however, the silting effect was concentrated in shallower depths, whereas the desilting was observed in the deepest parts. Moreover, the sedimentation rate in the analyzed area was linked to the total precipitation in the municipality during the concerning time frame, as well as to changes in land use that occurred over the past years throughout the watershed. This data indicates a call for management actions to reduce soil erosion in the watershed, as well as a need for desilting of the reservoirs in order to recover its storage capacity.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46570765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remediation of high concentration chromium contaminated soil by Enhanced Electrodynamic Method","authors":"Guo Lin, L. Jun, Chenxu Yao, Zhang Xiaocun","doi":"10.15446/ESRJ.V25N2.93896","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N2.93896","url":null,"abstract":"How to cite item Guo, L., Zhang, X., Chen, Y., & Liu, J. (2021). Remediation of high concentration chromium contaminated soil by Enhanced Electrodynamic Method. Earth Sciences Research Journal, 25(2), 247-253. DOI: https://doi.org/10.15446/ esrj.v25n2.93896 High concentration of chromium salt has caused serious pollution to the environment since its production. The longstanding chromium residue has polluted the soil, and the total chromium concentration of some polluted soil has reached 30000 mg / kg. For the remediation of chromium contaminated soil, the enhanced electrodynamic method was proposed. In order to improve the efficiency of electrokinetic remediation of chromium contaminated soil, two enhanced electrokinetic remediation technologies were proposed: Electrokinetic oxidation enhanced remediation technology and electrokinetic enhanced remediation technology. Cr (III) in soil was polluted by oxidant chromium oxide to increase the content of dissolved Cr (VI),so as to improve the efficiency of electric repair, in order to find a suitable PRB medium as a breakthrough to improve the repair efficiency. The experimental results show that compared with the traditional electrodynamic technology, the enhanced electrodynamic method can effectively improve the removal rate of total chromium in the soil, and provide technical support for the enhanced electrodynamic remediation of chromium contaminated soil. The pH control system makes the pH of anode and cathode electrolyte always maintain acidic, and the H+ migration speed is faster than that of OH-, and the pH of soil near the anode is lower than that near the cathode. ABSTRACT Remediation of high concentration chromium contaminated soil by Enhanced Electrodynamic Method","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"247-253"},"PeriodicalIF":0.9,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48076128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Historical precipitation patterns in the South-Southeast region of Mexico and future projections","authors":"M. Andrade-Velázquez, Ojilve Ramón Medrano Pérez","doi":"10.15446/ESRJ.V25N1.87255","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.87255","url":null,"abstract":"How to cite item Andrade-Velazquez, M., & Medrano-Perez, R. (2021). Historical precipitation patterns in the South-Southeast region of Mexico and future projections. Earth Sciences Research Journal, 25(1), 69-84. DOI: https://doi.org/10.15446/esrj. v25n1.87255 This study analyzed climate change scenarios and their potential impact on water availability for the South-Southeast region (SSR) of Mexico. Precipitation patterns were examined using the Standardized Precipitation Index for three emissions scenarios, Representative Concentration Pathway (RCP) 4.5, RCP 6.0, and RCP 8.5, during the periods of 1960-2016, 2015-2039 (near future), and 2075-2099 (far future). Historical changes in precipitation in the SSR indicated the presence of dry and wet events driven by El Niño-Southern Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multidecadal Oscillation, which are the regional climate modulators. However, the impact of these phases has not been quantified for the future. The results of our climate change projections show that the Grijalva and Usumacinta rivers and surrounding regions (Chiapas and Tabasco) will have an increase in the percentage of dry and wet events shortly (2015-2039), while there is a medium to a low probability of this occurrence in rest of the SSR. By 2075-2099, Grijalva and Usumacinta will continue to have a high probability of dry events due to climate change, and the Yucatan will also exhibit this behavior. RCP 4.5 was projected to be the wettest scenario for the study area, while RCP 8.5 projected an increase in dry events during both periods (2015-2039 and 2075-2099). RCP 6.0 projected a drier 2015-2039 and wetter 2075-2099. ABSTRACT Historical precipitation patterns in the South-Southeast region of Mexico and future projections","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"69-84"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43063836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of remote sensing technology in the analysis of periodic precipitation change in China’s Northern semi-arid area","authors":"Yannan Zhang, C. Liang","doi":"10.15446/ESRJ.V25N1.93925","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.93925","url":null,"abstract":"How to cite item Zhang, Y. & Liang, C. (2021). Application of remote sensing technology in the analysis of periodic precipitation change in China’s Northern semi-arid area. Earth Sciences Research Journal, 25(1), 85-91. DOI: https:// doi.org/10.15446/esrj.v25n1.93925 The remote sensing technology is used to analyze the periodic changes of precipitation in the semi-arid areas of northern China and provide a reference basis for precipitation prediction. Authors were based on GPS observation data and corresponding ground meteorological parameters to obtain the study area’s comprehensive water vapor content value and use precipitation and time to establish a linear regression equation based on the content value to express the precipitation trend change. The periodic structure and abnormal changes of the periodic precipitation series on different time scales were obtained through wavelet analysis, combined with anomaly calculations to analyze the increase and decrease precipitation characteristics. The Morlet continuous wavelet transform map was also used to reflect the periodic oscillations of precipitation on different time scales. The wavelet variance map was used to reflect the distribution of regional precipitation with scale years. The authors analyzed the cycle change characteristics of the comprehensive precipitation series in Harbin, Changchun, Shenyang, and Dalian. They concluded that the annual precipitation in the four regions showed a decreasing trend in 50 years. And through the wavelet cycle frequencydomain relationship change law, the change characteristics of precipitation in the northern semi-arid area in the entire time domain were obtained. ABSTRACT Application of remote sensing technology in the analysis of periodic precipitation change in China’s Northern semi-arid area","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"85-91"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42848199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic monitoring algorithm of natural resources in scenic spots based on MODIS Remote Sensing technology","authors":"Maolin Li","doi":"10.15446/ESRJ.V25N1.93869","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.93869","url":null,"abstract":"A dynamic monitoring algorithm of natural resources in scenic spots based on MODIS remote sensing technology is proposed to improve natural resources monitoring accuracy in scenic spots. The remote sensing images of scenic spots obtained by MODIS were preprocessed by TM image processing, atmospheric correction, and other technologies to get high-precision remote sensing images. The remote sensing images of scenic spots were segmented by the multi-scale segmentation method, and then the hierarchical supervision classification method was used. The change points of natural resources were extracted. The resource changes and independent variables of scenic spots were analyzed based on the least square method to realize the dynamic monitoring of natural resources in scenic locations. The experimental results show that the technique can accurately monitor the dynamic changes of forest resources and water resources in scenic spots, and the monitoring results have high accuracy.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"57-64"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48072508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Mechanical Analysis of Support Instability Risk along the Strike of Coalface in Thick Coal Seam with Large Dip Angle: A Case Study","authors":"Wei Zhang, Weisheng Zhang, Dongsheng Zhang, Dahong Qi, Z. He","doi":"10.15446/ESRJ.V25N1.74167","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.74167","url":null,"abstract":"How to cite item Zhang, W., Wang, T., Zhang, D., Zhang, Y., Xu, P., & Duan, X. (2021). A mechanical analysis of support instability risk along the strike of coalface in thick coal seam with large dip angle: a case study. Earth Sciences Research Journal, 25(1), 101-108. DOI: https://doi.org/10.15446/ esrj.v25n1.74167 Studying the support stability of a coalface with a large dip angle (LDA) and large mining height (LMH) under the corresponding conditions is essential to ensure safe and high-efficiency mining. This study is based on the #3up509 coalface of the Gaozhuang Coal Mine (GCM) affiliated with the Zaozhuang Mining Area. The authors analyzed the mechanical characteristics of support in the coalface with LDA and LMH. On this basis, the mechanical models for support tilting and sliding in the coalface were developed. Then, support stability along the coalface’s strike during the normal mining period (NMP) and special mining period (SMP) was analyzed. The results show that the critical support tilting resistance during the NMP is 52.2 kN, and the critical support sliding resistance is 183.75 kN. And for the SMP, the values are 229.7 kN and 4425 kN. The use of two-leg shield support, known as ZY6600-25.5/55 (its rated working resistance is 6600 kN), is investigated, which is proved reasonable for the coalface. Finally, some technical measures, such as installing an interlock set to fasten support and adjustable lifting jack, increasing the setting load of the support, and optimizing the support displacement method, are taken to improve the coalface’s overall support stability. The initial aim for safe and high-efficiency mining of the #3up509 coalface has been achieved through these measures. ABSTRACT A mechanical analysis of support instability risk along the strike of coalface in thick coal seam with large dip angle: a case study","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"101-108"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49488506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tracing method of Rare Earth Elements in surrounding rock of geological formation based on three-dimensional positioning algorithm","authors":"Yan Lv, L. Lu, M. Cao","doi":"10.15446/ESRJ.V25N1.93725","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.93725","url":null,"abstract":"How to cite item Lv, Y., Lu, L., & Cao, M. (2021). Tracing method of Rare Earth Elements in surrounding rock of geological formation based on threedimensional positioning algorithm. Earth Sciences Research Journal, 25(1), pending pages. DOI: https://doi.org/10.15446/esrj. v25n1.93725 Because of the interference of mass spectrum and non-mass spectrum, the tracing accuracy of rare earth elements in the surrounding rock of geological formation is low. Pretreatment of test sample reagent, dissolution of test sample residue, characterization of rare earth element doped materials, analysis of mass spectrometry and non-mass spectrometry interference in rare earth element tracking, using three-dimensional positioning algorithm to track rare earth elements in geological strata surrounding rock. In the experiment, five samples of surrounding rock of geological strata are selected as experimental indexes. The experimental results show that the tracking accuracy of four rare earth elements is high. ABSTRACT Tracing method of Rare Earth Elements in surrounding rock of geological formation based on three-dimensional positioning algorithm","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"21-28"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43221610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation analysis between multifractal characteristics of regional geomorphology and development of geological disasters","authors":"Y. Xiong","doi":"10.15446/ESRJ.V25N1.93700","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N1.93700","url":null,"abstract":"How to cite item Xiong, Y. (2021). Correlation analysis between multifractal characteristics of regional geomorphology and development of geological disasters. Earth Sciences Research Journal, 25(1), 49-55. DOI: https://doi.org/10.15446/ esrj.v25n1.93700 In view of the inaccuracy of the traditional correlation analysis method, this paper proposes a correlation analysis method between the multifractal characteristics of regional landforms and the development of geological disasters. Firstly, the multifractal characteristics of regional landforms are described by using the basic fractal characteristics of self-similarity or scale invariance. Then the corresponding relation table is established according to the width of the fractal spectrum and the number of landslides and hidden dangers, and the spatial relationship of geological disaster development is analyzed. Combined with the above-mentioned spatial relationship of geological disaster development and the multifractal characteristic data of regional landforms, the correlation coefficient between the two is calculated to complete the correlation analysis between the multifractal characteristics of regional geomorphology and the development of geological disasters. The experimental results show that compared with the traditional correlation analysis method, the correlation analysis results of the multifractal characteristics of regional geomorphology and the development of geological disasters are more accurate. ABSTRACT Correlation analysis between multifractal characteristics of regional geomorphology and development of geological disasters","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":"25 1","pages":"49-55"},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43045236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}