Earth Sciences Research Journal最新文献

{"title":"Mineralogy and geochemical signatures as indicators of differential weathering in natural soil profiles from the West Asturian-Leonese Zone (NW Iberia)","authors":"Sara Alcalde-Aparicio, M. Vidal-Bardán, E. Alonso-Herrero","doi":"10.15446/esrj.v26n1.81087","DOIUrl":"https://doi.org/10.15446/esrj.v26n1.81087","url":null,"abstract":"This paper presents detailed mineralogical results together with a geochemical characterization for a sequence of six natural soil profiles. Bedrock samples (R series) and overlying soil samples (S series) were characterized. The soil profiles are distributed in a series of Paleozoic lithological units from lower Ordovician to upper Carboniferous in age (Iberian Massif, NW Iberia). The lithological influence on mineral properties and geochemical composition and, how different weathering may be occurring under very similar temperate and acidic conditions, have been studied. Field observations together with laboratory analyses were indicative of differential weathering. So, a series of selected chemical indices and relations were applied to clarify this assumption. The mineralogy was analysed by Scanning electron microscopy (SEM-EDS), X-ray diffraction (XRD) of rock powder and soil oriented aggregates. X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectroscopy (ICP-MS) were applied to analyse chemical composition. The first results showed how major elements, SiO2, Al2O3 and Fe2O3, slightly enriched in the soil profiles, are consistent with the dominant mineralogy: quartz, chlorite, muscovite and/or illite, together with kaolinite and albite. The bases K2O, Na2O, CaO and MgO are also coherent with mineral composition and experience little variation, but are gradually removed in the profiles. The mobility of major elements leads to a general loss of bases and, in general, a slight enrichment in silica and sesquioxides. SiO2 is enriched, firstly accumulated in soils and partially depleted by dissolution as colloidal form. Al2O3 in some soils is slightly less than in former rocks, so other physical processes are expected to take place, involving clay removal with consequent aluminium depletion too. A special emphasis has been given to albite coexisting with kaolinite, firstly supposed to be directly inherited from parent substrates when present, but finally the chemical index PIA shows it was mainly due to mineral alteration of plagioclases. The best correlations to explain the albite alteration and kaolinitization progress were obtained with chemical indices PIA, CIW, CIA and Al2O3/Na2O ratio. This together with mineralogical signatures, suggest that kaolinite is the result of gradual dissolution due to the acid hydrolysis of albite in such acidic environments, which may also be attributed to the organic matter influence.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46253450","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":"Modeling of the large Miocene epithermal and porphyry gold deposits of Colombia using Monte Carlo simulations","authors":"Felipe Velásquez Ruiz, J. Martínez, Alejandra Tobón Acevedo, Alejandra Yepes Metaute, A. Zapata, Diana Paulina Cataño Salas","doi":"10.15446/esrj.v25n4.95289","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.95289","url":null,"abstract":"The Cauca metallogenic belt is an inter-Andean area located along the Cauca-Romeral fault zone, which is made up of a group of twelve Miocene magmatic-hydrothermal Au-Ag-Cu mineral deposits positioned between the Western and Central Cordillera of Colombia. In addition to being a widely developed region in exploration and exploitation with known Au endowments of over 1,700 tons, this area represents an exceptional metallogenetic laboratory for modeling a typical Andean-type mineralization from a calc-alkaline source with high Sr/Y ratios. Efficiency processes such as ion and halogen transport, oxygen fugacity and sulfur content have been extensively studied with a geochemical approach; however, the quantification and modeling of these efficiency processes currently debated. Through multiple iterations using Monte Carlo simulations (N > 2 million), the modeled reservoirs corresponding to the upper crust, using a high flux of dacitic magma of 0.007 km3/year and efficiencies of 1 – 2 %, showed that gold endowments bear heavily with magmatic and hydrothermal Au deposits in the Cauca Metallogenic Belt. Outcomes including Au endowments up to 1,000 tons can be obtained for reservoirs below 400 km3 of hydrous melt in brief mineralization intervals between 40 to 120 ka and for volumes of 400 to 800 km3 in a 120 to 200 ka window. In contrast, the hypothetical reservoirs for the lower and middle crust, through a basaltic calc-alkaline magma flux between 0.0007 and 0.0011 km3/year, an efficiency of ~0.7%, and pressures below 5 kbar, showed sufficient available content of exsolvable H2O and gold to feed the reservoirs in the upper crust or to generate gold deposits from them, but in longer time intervals (>1 Ma).","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49592184","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":"Anomalous geoelectric potential variations observed along a gas pipeline section in Argentine, possible intensification with variations of the Earth’s magnetic field","authors":"P. Larocca, M. A. Arecco, A. C. Macrino","doi":"10.15446/esrj.v25n4.91059","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.91059","url":null,"abstract":"Significant anomalous geoelectric potential variations have been observed in a section of the NEUBA II gas pipeline along its route in the district of Saavedra, near the area of Goyena, province of Buenos Aires (Argentine), where it goes through major lithological, edaphological and hydrological variations. Detailed research was conducted, showing that these disturbances may be intensified with variations of the Earth’s magnetic field, during a magnetic storm, as the pipe-to-soil potential (PSP) values remained constant for weeks and then fluctuations from 0.1 V to 0.15 V were recorded in various parts of the pipeline. On the other hand, to provide another analysis of these variations, models based on the distributed source transmission line (DSTL) theory were used, proposing a uniform geoelectric field along the pipeline route. A design was proposed that would allow modeling the response of the pipeline to variations of induced geoelectric fields, taking into account their intensification based on points of discontinuity due to subsoil characteristics or differences in its structure. Good consistency was achieved between the observed and modeled PSPs. The analysis and monitoring of these PSPs is a useful tool to identify the potential risks caused by geomagnetically induced currents in the pipes that would increase the effects due to the structure or the environment in which it is buried.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41863708","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":"Runoff Curve Number (CN model) Evaluation Under Tropical Conditions","authors":"Daniela Calero Mosquera, Fanny Hoyos Villada, Enrique A. Torres Prieto","doi":"10.15446/esrj.v25n4.95321","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.95321","url":null,"abstract":"In tropical countries the Curve Number method (CN) of the Soil Conservation Service (SCS) is widely used in civil engineering (to calculate drainage infrastructure) as well as in agricultural and environmental studies. However, little is known about the accuracy of CN method in tropical watersheds. To reveal the CN method accuracy, this study compares the CN method results with field data measured in an Andean micro watershed. For this, CN values for the tropical micro watershed \"La Vega\" were identified using the tables proposed by the SCS and its respective moisture and slope corrections (CNAMC2S); subsequently CN values were derived from 55 events (CNQ) in which runoff and rainfall were measured. It was observed a different of 27% between CNQ and CNAMC2S (CNQ = 80, CNAMC2S 58.1). According to that, the data shows that in the tropical micro watershed evaluated in this study, the SCS method overestimated runoff. The CN model of the SCS is strongly influenced by the antecedent humidity and its impact becomes stronger after high rainfalls records; however, the antecedent humidity influence was not observed in measured runoff data. Despite the CN – SCS model did not present a relationship between CN and precipitation, this relationship was observed in measure data. This study shows that CN method has some inaccuracies and it requires further studies to know its applicability in tropical conditions. \u0000 ","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46163738","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":"Factors affecting topographic thresholds in gully erosion occurrence and its management using predictive machine learning models","authors":"M. Valipour, N. Mohseni, S. Hosseinzadeh","doi":"10.15446/esrj.v25n4.95748","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.95748","url":null,"abstract":"Soil degradation induced by gully erosion represents a worldwide problem in the many arid and semi-arid countries, such as Iran. This study assessed: (1) the importance of variables that control gully erosion using the Boruta algorithm, (2) the relationship among causative variables and gullied locations using the evidential belief function model (EBF), and (3) gully erosion development using the algorithms of boosted regression tree (BRT) and support vector machine (SVM). Based on the results of the Boruta algorithm, slope, land use, lithology, plan curvature, and elevation were the most important factors controlling gully erosion. The results of the EBF model showed the predominance of gully erosion on rangeland and loess-marl deposition. The predominance of gullied locations on the concave positions, with the slope of 5°–20° in the vicinity of drainage lines, illustrates a preferential topographic zone and, therefore, a terrain threshold for gullying. The correlation of gullied locations with rangelands and weak soils in concave positions demonstrates that the interactions among soil characteristics, topography, and land use stimulate a low topographic threshold for gullies development. These relationships are consistent with the threshold concept that a given soil, land use, and climate within a given landscape encourage a given drainage area and a critical soil surface slope that are necessary for gully incision. Furthermore, the BRF-SVM had the highest efficiency and the lowest root mean square error, followed by BRT for predicting gully development, compared with LN-SVM algorithm. The application of two machine learning methods for predicting the gully head cut susceptibility in northern Iran showed that the maps generated by these algorithms could provide an appropriate strategy for geo-conservation and restoration efforts in gullying-prone areas.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47924826","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 Modelling Study by Factorial Design on GNSS Positioning","authors":"V. Ilçi, Yasemin Şişman","doi":"10.15446/esrj.v25n4.95060","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.95060","url":null,"abstract":"Although researchers have widely studied the analysis and modelling of error sources on Global Navigation Satellite Systems positioning, some of these errors have not been eliminated significantly and only some of the Global Navigation Satellite System’s data are modelled. The present work was undertaken to determine the effect of different variables, namely: season, the number of visible satellites, and dilution of precision on the efficiency of horizontal and vertical CORS (Continuously Operating Reference Stations) positioning. For this aim, the CORS data was collected at 14 different test points during 600 epochs with 1-second intervals. Factorial designs supply an efficient solution to understand the impact of several factors on a response variable. A full factorial design with three factors at two levels was applied for these purposes. According to the results of the full factorial design, all factors significantly affected the response variable. Also, the interaction effects of factors were analysed on the CORS horizontal and vertical positioning. The regression equations were obtained for all situations.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47317057","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":"Geoid undulation prediction using ANNs (RBFNN and GRNN), multiple linear regression (MLR), and interpolation methods: A comparative study","authors":"B. Konakoglu, Alper Akar","doi":"10.15446/esrj.v25n4.91195","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.91195","url":null,"abstract":"The present work aimed to develop a prediction model to estimate geoid undulation and to compare its efficiency with other methods including radial basis function neural network (RBFNN), generalized regression neural network (GRNN), multiple linear regression (MLR) and, ten different interpolation methods. In this study, the k-fold cross-validation method was used to evaluate the model and its behavior on the independent dataset. With this validation method, each of a k number of groups has the chance to be divided into training and testing data. The performances of the methods were evaluated in terms of the root mean square error (RMSE) mean absolute error (MAE), Nash–Sutcliffe efficiency coefficient (NSE), and correlation coefficient (R2) and using graphical indicators. The evaluation of the performance of the datasets obtained using cross-validation was done in two ways. If we accept the method having the minimum error result as the most appropriate method, the natural neighbor (NN) method in the DS#5 dataset gave better results than the other methods (RMSE=0.14173  m, MAE=0.09729 m, NSE=0.98986, and R2=0.99011. On the other hand, it has been observed that, the GRNN method exhibited the best performance, on average, with RMSE=0.18539 m, MAE=0.13676 m, NSE=0.98229, and R2=0.98249.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44211055","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":"Seismic site classification of the Costa Rican Strong-Motion Network based on VS30 measurements and site fundamental period","authors":"L. Pinzón, D. Hidalgo-Leiva, Aarón Moya-Fernández, Víctor Schmidt-Díaz, L. Pujades","doi":"10.15446/esrj.v25n4.93927","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.93927","url":null,"abstract":"In this paper, a new seismic site classification for the Costa Rican Strong-Motion Network (CRSMN) is proposed. The soil profile classification of the Costa Rican Seismic Code based on the average shear-wave velocity of the top 30 m (VS30) is used as a reference. The site fundamental period (Tf) is included as a parameter to complement the existing characterization. For this, the VS30 measurements from 52 accelerometric stations are related to the site fundamental period obtained through horizontal-to-vertical spectral ratios (HVSR) using ground motion records from the Costa Rican Strong-Motion Database. The H/V ratios are estimated with 5% damped acceleration response spectra and with traditional Fourier amplitude spectra from the S-wave window. From the relation between VS30 and Tf, different ranges of Tf are assigned to the existing soil profile classification and a graph with three-lines and four-areas is proposed to classify the stations of the CRSMN.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44770675","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":"Investigating the effects of groundwater level changes on GNSS observations in the Konya Closed Basin","authors":"H. Erdogan, O. Oktar, Cemil Gezgin, F. Poyraz, N. Arslan, F. Yilmazturk","doi":"10.15446/esrj.v25n4.92490","DOIUrl":"https://doi.org/10.15446/esrj.v25n4.92490","url":null,"abstract":"The Konya Closed Basin (KCB) that inhabited by approximately 4 million people has a semi-arid climate and has been an important agricultural and economic production area with its alluvial fertile soils. In recent years, the use of groundwater as a main source in the intense need for irrigation in the basin due to climate change, drought and wrong agricultural policies triggered land subsidence in the basin by causing the aquifer system compaction. In this study, the effects of groundwater level changes obtained from groundwater monitoring stations on the positions of continuously operating GNSS stations located in KCB were investigated by time series analysis. As a result of trend component analyses of time series processed based on the ITRF08 fixed frame, it was determined that the horizontal positions of stations in this region were moving in the northeast direction (18.88 mm/year). For the up coordinates, while stations ANRK, KLUU, and NIGD had movements (0.56 mm/year) in the up direction, the other stations moved in the down direction. The vertical movement of KNY1 station based on 560-day data was in the down (-) direction, with an annual movement of 70.96 mm, and this was the maximum movement or velocity compared to the other stations in this region. The trend analysis of 19 wells revealed linear groundwater level changes in the down direction with a mean value of -39.22 cm/year. The decrease in the water level of the wells in the Konya Closed Basin was statistically significant for the majority of the wells and at meter level in some wells. It was determined that the linear decrease was generally caused by the reduced level of groundwater in this region. The periodic component analysis showed that the movements of the GNSS stations changed from a day to a year due to several factors, such as atmospheric and hydrological loading and climatic effects.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47090233","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":"Petrographic and geochemical features of Gimo marble, Gole area, Kurdistan Region, Iraq: constraints on its protolith's origin and depositional environment","authors":"Tola A. Mirza, S. Kalaitzidis, Sardar S. Fatah, Sophia Tsiotou","doi":"10.15446/ESRJ.V25N3.88686","DOIUrl":"https://doi.org/10.15446/ESRJ.V25N3.88686","url":null,"abstract":"It is essential to identify marbles' petrographic and geochemical characteristics to determine the palaeo-environmental settings where their carbonate protoliths formed. The petrogenesis of massive Gimo marbles in the Gole area, Kurdistan Region of northeast Iraq, was investigated in this study through a combination of field mapping, petrographic, and geochemical techniques. Petrographic examination of these marbles reveals that mineral compositions are similar in all samples, with both homeoblastic and mosaic textures occurring, in addition to opaque grains that provide evidence of mineralization. Geochemical analyses show that the average calcium carbonate content of the marble is 94.96%; hence, the marble is lithologically characterized as a pure calcite marble. In most samples, the silica content was below 2 wt.%, with high values related to quartz veinlets. A range of geochemical indices and Post-Archean Australian Shale (PAAS–normalized rare earth element (REE) patterns) suggest that the limestone protolith was deposited in a shallow, near-shore marine environment on a continental margin, with very low input of detrital material. The negative Ce anomalies indicate that the protoliths of the Gimo marbles were carbonate rocks of a sedimentary origin.","PeriodicalId":11456,"journal":{"name":"Earth Sciences Research Journal","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42563639","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}