The granitoids of Guera Massif are composed of biotite-granite, amphibole-biotite granite and gabbro-diorite and commonly contain micro granular mafic enclaves which vary from monzogabbro to syenite composition. They are metaluminous, high-K calc-alkaline to shoshonitic series. Gabbro-diorite rocks are magnesian while amphibole-biotite granites are magnesian to ferroan, and biotite granites are ferroan. They are enriched in LREEs relative to HREE and display negative anomalies in Nb, Ta and Ti. Fields relationships, petrology and geochemistry indicate that mixing and mingling processes could be more relevant for the genesis of granitoids associated to fractional crystallization. Thus, the presence of mafic enclaves of gabbro-diorite composition in the granites, the resumption of alkaline feldspar xenocrystals in the gabbro-diorites, as well as the linear correlation between the granites and the gabbro-diorites and the intermediate position of the mafic enclaves between the two formations, enable us to propose magmatic mixing as the major process that presided over the evolution of the Guera granitoids. The delamination of the continental lithosphere during the post-collisional phase of the Pan-African orogeny would have caused the partial melting of the subduction-modofied mantle and lower continental crust and thus produced the magmas of the Guera granitoids.
{"title":"Petrology and Geochemical Characteristic of Granitoids From Guéra Massif in the Central Part of Chad: An Example of Mixing Magmas","authors":"Diontar Mbaihoudou, Kwékam Maurice, Fozing Eric Martial, Kagou Dongmo Armand, Tcheumenak Kouémo Jules","doi":"10.5539/esr.v9n2p66","DOIUrl":"https://doi.org/10.5539/esr.v9n2p66","url":null,"abstract":"The granitoids of Guera Massif are composed of biotite-granite, amphibole-biotite granite and gabbro-diorite and commonly contain micro granular mafic enclaves which vary from monzogabbro to syenite composition. They are metaluminous, high-K calc-alkaline to shoshonitic series. Gabbro-diorite rocks are magnesian while amphibole-biotite granites are magnesian to ferroan, and biotite granites are ferroan. They are enriched in LREEs relative to HREE and display negative anomalies in Nb, Ta and Ti. Fields relationships, petrology and geochemistry indicate that mixing and mingling processes could be more relevant for the genesis of granitoids associated to fractional crystallization. Thus, the presence of mafic enclaves of gabbro-diorite composition in the granites, the resumption of alkaline feldspar xenocrystals in the gabbro-diorites, as well as the linear correlation between the granites and the gabbro-diorites and the intermediate position of the mafic enclaves between the two formations, enable us to propose magmatic mixing as the major process that presided over the evolution of the Guera granitoids. The delamination of the continental lithosphere during the post-collisional phase of the Pan-African orogeny would have caused the partial melting of the subduction-modofied mantle and lower continental crust and thus produced the magmas of the Guera granitoids.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76331321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Olivier Ulrich Igor Owono Amougou, T. N. Mbarga, A. Meying, Jean Marcel Abate Essi, J. Mono, Didier Pepogo Manvele, Christian Gislain Leonel Ngah
The collision between the Congo Craton and the Pan African fold belt of Central Africa had great impacts on the geological and tectonic points of view, notably the installation of several tectonic accidents such as faults, fractures, dikes, folds, domes. This aeromagnetic study is based on Paterson's aeromagnetic data interpretations through the use of multiple operators. These data were processed by Oasis Montaj software. The total magnetic intensity map reduced to the equator (RTE-TMI) shows important anomalies features the major important regional anomalies. Maps of the vertical gradient, analytical signal and tilt angle maps have meanwhile highlighted several short wavelength anomalies assimilated to folding, dykes, fractures or faults. The map of maxima upward to 2 km allowed to establish the structural map of the study area. It turns out that the different types of geological accidents follow ENE-WSW, ESE-WNW, NE-SW, NW-SE and even E-W and N-S directions. All these directions are very similar to the geological history of the area. Anything that seems to confirm that the study area was the scene of intense tectonic movements resulting from the collision between the Congo Craton and the Central Africa Fold Belt.
{"title":"Interpretation of Aeromagnetic Data to Investigate Crustal Structures of the Contact Congo Craton - Pan-African Belt at the Eastern Cameroon","authors":"Olivier Ulrich Igor Owono Amougou, T. N. Mbarga, A. Meying, Jean Marcel Abate Essi, J. Mono, Didier Pepogo Manvele, Christian Gislain Leonel Ngah","doi":"10.5539/esr.v9n2p48","DOIUrl":"https://doi.org/10.5539/esr.v9n2p48","url":null,"abstract":"The collision between the Congo Craton and the Pan African fold belt of Central Africa had great impacts on the geological and tectonic points of view, notably the installation of several tectonic accidents such as faults, fractures, dikes, folds, domes. This aeromagnetic study is based on Paterson's aeromagnetic data interpretations through the use of multiple operators. These data were processed by Oasis Montaj software. The total magnetic intensity map reduced to the equator (RTE-TMI) shows important anomalies features the major important regional anomalies. Maps of the vertical gradient, analytical signal and tilt angle maps have meanwhile highlighted several short wavelength anomalies assimilated to folding, dykes, fractures or faults. The map of maxima upward to 2 km allowed to establish the structural map of the study area. It turns out that the different types of geological accidents follow ENE-WSW, ESE-WNW, NE-SW, NW-SE and even E-W and N-S directions. All these directions are very similar to the geological history of the area. Anything that seems to confirm that the study area was the scene of intense tectonic movements resulting from the collision between the Congo Craton and the Central Africa Fold Belt.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83883539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Srivastava, A. Krishna, S. Jawed, Pallavi Sarkhel
Crystalline minerals in granite rocks has been quantatively analysed by powder X-ray diffraction (XRD) and Scanning Electron Microscope supported with Energy Dispersed Spectroscopy (SEM-EDS). SEM microphotograph reveals that rock is dominated by brightly illuminated quartz imbedded in the matrix with mica and other minor minerals. The X-ray mineral composition data have been plotted with SEM-EDS mineral composition, data shows that the composition obtained by two technique are in consistent within the experimental limit and in good agreement. Further plot of chemical composition of constituent oxides of granite sample by XRD and SEM-EDS confirm the consistency of two technique and similarity with Jharkhand mean granite composition. Silica composition have been plotted with trace element Pb, Ba, Zr, Rb, and Alumina composition with Pb , Ba, Zr and Rb shows that these elements are randomly imbedded in the matrix with almost uniform composition. Al2O 3 composition have been plotted with Ba, Pb, and Zr shows almost constant composition in all the five samples. Based on XRD and SEM-EDS results, it was reveals that granite sample from the study areas are peraluminius rocks composed of mainly quartz, muscovite, kaolinite, chlorite and albite.
{"title":"Quantitative Minerological Analysis of Some Granite Rocks of Deoghar Jharkhand","authors":"P. Srivastava, A. Krishna, S. Jawed, Pallavi Sarkhel","doi":"10.5539/esr.v9n2p30","DOIUrl":"https://doi.org/10.5539/esr.v9n2p30","url":null,"abstract":"Crystalline minerals in granite rocks has been quantatively analysed by powder X-ray diffraction (XRD) and Scanning Electron Microscope supported with Energy Dispersed Spectroscopy (SEM-EDS). SEM microphotograph reveals that rock is dominated by brightly illuminated quartz imbedded in the matrix with mica and other minor minerals. The X-ray mineral composition data have been plotted with SEM-EDS mineral composition, data shows that the composition obtained by two technique are in consistent within the experimental limit and in good agreement. Further plot of chemical composition of constituent oxides of granite sample by XRD and SEM-EDS confirm the consistency of two technique and similarity with Jharkhand mean granite composition. Silica composition have been plotted with trace element Pb, Ba, Zr, Rb, and Alumina composition with Pb , Ba, Zr and Rb shows that these elements are randomly imbedded in the matrix with almost uniform composition. Al2O 3 composition have been plotted with Ba, Pb, and Zr shows almost constant composition in all the five samples. Based on XRD and SEM-EDS results, it was reveals that granite sample from the study areas are peraluminius rocks composed of mainly quartz, muscovite, kaolinite, chlorite and albite.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80067235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tchouankam Klorane Junie, Mbog Michel Bertrand, Bayiga ElieConstant, Tassongwa Bernard, NgonNgon Gilbert François, Apouamoun Yiagnigni Roland, Kenfack JeanVictor, E. Jacques
The aim of this work is the valorization of the economic potential of gold in the Batouri region. The study is undertaken on five sites of which two alluvials (Djengo and Mongonam localities) made up of flat and river gold, two eluvials (Kambele and Bote) containing gold of veins in quarries, and one semi mechanized exploitation (METALICON) working on the two previous types. Laboratory works consist of traditional melting, determination of the various grades of gold through densimetry and spectrometry analysis and refining using the Miller Chloration method. The main results from these analyses are- i) recovery concentration is low, (about 0.5 g/t) for the traditional mining and higher with the semi mechanization (1.5-2 g/t). Densimetry and spectrometry analyses show that gold of semi mechanized sites has an average grade of about 24 carats, 22 carats and 20 for alluvial and eluvial gold respectively. ii) For 26 kg of gold refined, a weight of 16.681 kg is obtained at a cost of 4 051 946 (four million fifty one thousand and nine hundred forty six) CFA F. Spectrometry analyses reveal the presence of silver and copper impurities, elements that can still be valorized through the presence of a gold refining unit. Hence, the absence of a gold refining unit in our country leads to poor transformation of its ores and loss of devices.
{"title":"Economic Potential of Gold in Batouri (Eastern Cameroon)","authors":"Tchouankam Klorane Junie, Mbog Michel Bertrand, Bayiga ElieConstant, Tassongwa Bernard, NgonNgon Gilbert François, Apouamoun Yiagnigni Roland, Kenfack JeanVictor, E. Jacques","doi":"10.5539/esr.v9n2p21","DOIUrl":"https://doi.org/10.5539/esr.v9n2p21","url":null,"abstract":"The aim of this work is the valorization of the economic potential of gold in the Batouri region. The study is undertaken on five sites of which two alluvials (Djengo and Mongonam localities) made up of flat and river gold, two eluvials (Kambele and Bote) containing gold of veins in quarries, and one semi mechanized exploitation (METALICON) working on the two previous types. Laboratory works consist of traditional melting, determination of the various grades of gold through densimetry and spectrometry analysis and refining using the Miller Chloration method. The main results from these analyses are- i) recovery concentration is low, (about 0.5 g/t) for the traditional mining and higher with the semi mechanization (1.5-2 g/t). Densimetry and spectrometry analyses show that gold of semi mechanized sites has an average grade of about 24 carats, 22 carats and 20 for alluvial and eluvial gold respectively. ii) For 26 kg of gold refined, a weight of 16.681 kg is obtained at a cost of 4 051 946 (four million fifty one thousand and nine hundred forty six) CFA F. Spectrometry analyses reveal the presence of silver and copper impurities, elements that can still be valorized through the presence of a gold refining unit. Hence, the absence of a gold refining unit in our country leads to poor transformation of its ores and loss of devices.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81322088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Abdulsamad, Saleh A. Emhanna, Muayid B. Asmaeil, Ahmed A. Alwddani, F. M. Rasheed, Abdulsalam M. AlhaddadI, Emad A. Alashhab, Ali K. Khalifa, Mohammed F. El Hassi
The Upper Cretaceous to Upper Palaeocene rocks of the Zimam Formation along the southwestern escarpment of the Hun Graben of NW Libya have been stratigraphically investigated from two stratigraphical sections in wadi Tar al Kabir. The field investigations led to the recognition of three members, from the oldest to the youngest, the Lower Tar Member, the Upper Tar Member and the Had Member. Eight sedimentary facies were distinguished at outcrop-scale and several microfacies were recognized and the outcome indicates that the depositions of the Zimam Formation are corresponding to two transgressive-regressive sedimentary cycles. The first cycle is attributed to the Lower Tar Member in which small planktonic foraminifera is quite common in the Campanian whereas the larger benthic foraminifera, namely, Omphalocyclus macroporus and Siderolites calcitrapoides are abundant in the Maastrichtian. The last occurrence of the latter two taxa, however, was used to delineate the contact between the Maastrichtian and Danian stages in the studied sequence. Up-sequence the sediments of the Upper Tar Member along with the overlying Had Member correspond to the second transgressive-regressive sedimentary cycle. Herein, the Upper Tar Member is enriched by small benthic foraminifera; Neoeponides duwi and Cibicides cf. libycus, and has been ascribed to the Danian (Lower Palaeocene). The reaming sediments of Zimam Formation, however, are belonging to the overlying Had Member and is tentatively ascribed to the Selandian (Upper Palaeocene) based on the last occurrence of the Danian fauna and the total range of the codiacean algae Ovulites morelleti.
利用wadi Tar al Kabir的两个地层剖面，对利比亚西北部洪地陷西南断崖上白垩统至上古新统Zimam组岩石进行了地层学研究。通过实地考察，确定了由最老到最年轻的三段:下焦油段、上焦油段和哈德段。在露头尺度上划分出8个沉积相，识别出若干微相，表明子马组沉积对应于2个海侵-退旋回。第一个旋回属于下Tar段，在Campanian中小型浮游有孔虫相当普遍，而在Maastrichtian中则有大量的大型底栖有孔虫，即Omphalocyclus macroporus和Siderolites calcitrapoides。然而，后两个分类群的最后一次出现被用来划定所研究序列中马斯特里赫特期和达尼安期之间的接触。上焦油段与上覆的哈德段的上序沉积对应于第二次海侵-海退沉积旋回。在此，上焦油段富含小型底栖有孔虫;Neoeponides duwi和Cibicides cf. libycus，并被归属于Danian(下古新世)。而Zimam组的孔洞沉积物则属于上覆Had段，根据最后出现的Danian动物群和codiaceae藻类Ovulites morelleti的总范围，初步将其归属于Selandian(上古新世)。
{"title":"Stratigraphy and Sedimentology of Upper Cretaceous to Upper Palaeocene Succession in Zimam Formation Along Wadi Tar al Kabir, NW Libya","authors":"E. Abdulsamad, Saleh A. Emhanna, Muayid B. Asmaeil, Ahmed A. Alwddani, F. M. Rasheed, Abdulsalam M. AlhaddadI, Emad A. Alashhab, Ali K. Khalifa, Mohammed F. El Hassi","doi":"10.5539/esr.v9n2p1","DOIUrl":"https://doi.org/10.5539/esr.v9n2p1","url":null,"abstract":"The Upper Cretaceous to Upper Palaeocene rocks of the Zimam Formation along the southwestern escarpment of the Hun Graben of NW Libya have been stratigraphically investigated from two stratigraphical sections in wadi Tar al Kabir. The field investigations led to the recognition of three members, from the oldest to the youngest, the Lower Tar Member, the Upper Tar Member and the Had Member. Eight sedimentary facies were distinguished at outcrop-scale and several microfacies were recognized and the outcome indicates that the depositions of the Zimam Formation are corresponding to two transgressive-regressive sedimentary cycles. The first cycle is attributed to the Lower Tar Member in which small planktonic foraminifera is quite common in the Campanian whereas the larger benthic foraminifera, namely, Omphalocyclus macroporus and Siderolites calcitrapoides are abundant in the Maastrichtian. The last occurrence of the latter two taxa, however, was used to delineate the contact between the Maastrichtian and Danian stages in the studied sequence. Up-sequence the sediments of the Upper Tar Member along with the overlying Had Member correspond to the second transgressive-regressive sedimentary cycle. Herein, the Upper Tar Member is enriched by small benthic foraminifera; Neoeponides duwi and Cibicides cf. libycus, and has been ascribed to the Danian (Lower Palaeocene). The reaming sediments of Zimam Formation, however, are belonging to the overlying Had Member and is tentatively ascribed to the Selandian (Upper Palaeocene) based on the last occurrence of the Danian fauna and the total range of the codiacean algae Ovulites morelleti.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79239978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pisith Mao, H. Shimada, A. Hamanaka, Sugeng Wahyudi, Jiro Oya, Naung Naung
A study of multiple seams longwall mining is proposed to investigate its applicability in Indonesia coal mine. The study area of this research is PT Gerbang Daya Mandiri (GDM) coal mine located in East Kalimantan Island. The study of seam interaction is crucial for developing multiple seams longwall mining especially when it comes to weak rock conditions which are usually found in most of the coal reserves in Indonesia. This paper will use numerical simulation to investigate the effect of the first mined-out seam on the development of the second coal seam gate-entry by considering a couple of key parameters including depth of the coal seam and interburden length. The simulation model consists of two main indicators for instability which include failure zone, the contour of safety factor. The results show that the effect of seam interaction on gate-entry has different intensity based on the thickness of the interburden and coal seam depth. This work also provided appropriate support configuration for maintaining the stability of gate-entry.
提出了多煤层长壁开采的研究方案，以探讨其在印尼煤矿的适用性。本研究的研究区域是位于东加里曼丹岛的PT Gerbang Daya Mandiri (GDM)煤矿。煤层相互作用的研究对于开展多煤层长壁开采至关重要，特别是在印度尼西亚大部分煤炭储量普遍存在的弱岩条件下。本文将采用数值模拟的方法，考虑煤层深度和夹层长度等关键参数，研究第一次采空区对第二次煤层巷道发育的影响。该仿真模型由两个主要失稳指标组成，即失效区域和安全系数轮廓。结果表明:煤层相互作用对巷道进煤的影响程度随夹层厚度和煤层深度的不同而不同;这项工作也为维持入口的稳定性提供了适当的支撑配置。
{"title":"Three-Dimensional Analysis of Gate-Entry Stability in Multiple Seams Longwall Coal Mine Under Weak Rock Conditions","authors":"Pisith Mao, H. Shimada, A. Hamanaka, Sugeng Wahyudi, Jiro Oya, Naung Naung","doi":"10.5539/esr.v9n1p72","DOIUrl":"https://doi.org/10.5539/esr.v9n1p72","url":null,"abstract":"A study of multiple seams longwall mining is proposed to investigate its applicability in Indonesia coal mine. The study area of this research is PT Gerbang Daya Mandiri (GDM) coal mine located in East Kalimantan Island. The study of seam interaction is crucial for developing multiple seams longwall mining especially when it comes to weak rock conditions which are usually found in most of the coal reserves in Indonesia. This paper will use numerical simulation to investigate the effect of the first mined-out seam on the development of the second coal seam gate-entry by considering a couple of key parameters including depth of the coal seam and interburden length. The simulation model consists of two main indicators for instability which include failure zone, the contour of safety factor. The results show that the effect of seam interaction on gate-entry has different intensity based on the thickness of the interburden and coal seam depth. This work also provided appropriate support configuration for maintaining the stability of gate-entry.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84919347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Beatriz M. Dias, V. Velázquez, R. F. Lucena, J. M. A. Sobrinho
The technique of description and characterization of rocks with the aid of a polarized light microscope is a well-established practice in the fields of mineralogy and petrology. However, because geological materials are inherently highly variable on a small scale, capturing good-quality images, particularly of the fine details present in the mineral grains that compose the rock, is the main difficulty encountered when a thin section is examined under a petrographic microscope. Combining petrographic concepts and digital image processing methods, the principal aim of this paper is to provide a practical approach to digital image treatment with specific software, and its immediate application in the micromorphological characterization of minerals. In addition to the basic calibration of color, brightness, and contrast, three different methods of digital image processing in the spatial domain, following the principles of embossed surface, negative image, and edge detection techniques, were applied to the images. The use of these primary filters was found to be efficient for detailed characterization of the mineralogical phases involved in the different types of microstructures. However, special care must be taken regarding the sensitivity and accuracy parameters to avoid the exclusion of information or the addition of noise to the image. Although research has focused on the distinction of several types of textural features in rock-forming minerals, these techniques can be employed in other areas of investigation, in both academic and industrial settings, to diagnose textures of microtectonic deformation, soil micromorphological features, the proportions of the original ingredients in concretes, and the mineralogical modal determination of ceramics of archeological origin and to characterize mineral raw materials for the manufacture of technological products.
{"title":"Petrographic Microscope Digital Image Processing Technique for Texture and Microstructure Interpretation of Earth Materials","authors":"Beatriz M. Dias, V. Velázquez, R. F. Lucena, J. M. A. Sobrinho","doi":"10.5539/esr.v9n1p58","DOIUrl":"https://doi.org/10.5539/esr.v9n1p58","url":null,"abstract":"The technique of description and characterization of rocks with the aid of a polarized light microscope is a well-established practice in the fields of mineralogy and petrology. However, because geological materials are inherently highly variable on a small scale, capturing good-quality images, particularly of the fine details present in the mineral grains that compose the rock, is the main difficulty encountered when a thin section is examined under a petrographic microscope. Combining petrographic concepts and digital image processing methods, the principal aim of this paper is to provide a practical approach to digital image treatment with specific software, and its immediate application in the micromorphological characterization of minerals. In addition to the basic calibration of color, brightness, and contrast, three different methods of digital image processing in the spatial domain, following the principles of embossed surface, negative image, and edge detection techniques, were applied to the images. The use of these primary filters was found to be efficient for detailed characterization of the mineralogical phases involved in the different types of microstructures. However, special care must be taken regarding the sensitivity and accuracy parameters to avoid the exclusion of information or the addition of noise to the image. Although research has focused on the distinction of several types of textural features in rock-forming minerals, these techniques can be employed in other areas of investigation, in both academic and industrial settings, to diagnose textures of microtectonic deformation, soil micromorphological features, the proportions of the original ingredients in concretes, and the mineralogical modal determination of ceramics of archeological origin and to characterize mineral raw materials for the manufacture of technological products.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80080090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Divide crossings (or low points or gaps) notched into the North American east-west continental divide segments completely encircling Wyoming’s Great Divide Basin interior drainage region (as observed on detailed topographic maps) are used to compare the commonly accepted regional geomorphology paradigm with a fundamentally different and new regional geomorphology paradigm. Paradigms are sets of rules governing how a scientific discipline conducts its research and are judged on their ability to explain observed evidence. Published literature is used to contrast an accepted paradigm interpretation that east-oriented drainage previously flowed across what is now the Great Divide Basin with the new paradigm basic requirement that mountain range and continental divide uplift occurred while immense south-oriented floods flowed across them. Numerous divide crossings are notched into the continental divide segments now completely encircling the relatively flat-floored Great Divide Basin interior drainage area and divide crossings observed along each of the Great Divide Basin’s north, east, south, and west margins are described and interpreted first from the accepted paradigm perspective (using published literature interpretations to the extent possible) and second from the new paradigm perspective. The published literature does not mention most of the described divide crossings, much less provide explanations for their origins, perhaps because the accepted paradigm cannot satisfactorily explain those origins. In contrast the new paradigm successfully explains most if not all of the described (and observed, but undescribed) divide crossings, although the new paradigm requires a completely different middle and late Cenozoic regional geologic history than what most published regional geology literature describes.
{"title":"Use of Topographic Map Evidence From Drainage Divides Surrounding Wyoming’s Great Divide Basin to Compare Two Fundamentally Different Regional Geomorphology Paradigms","authors":"E. Clausen","doi":"10.5539/ESR.V9N1P45","DOIUrl":"https://doi.org/10.5539/ESR.V9N1P45","url":null,"abstract":"Divide crossings (or low points or gaps) notched into the North American east-west continental divide segments completely encircling Wyoming’s Great Divide Basin interior drainage region (as observed on detailed topographic maps) are used to compare the commonly accepted regional geomorphology paradigm with a fundamentally different and new regional geomorphology paradigm. Paradigms are sets of rules governing how a scientific discipline conducts its research and are judged on their ability to explain observed evidence. Published literature is used to contrast an accepted paradigm interpretation that east-oriented drainage previously flowed across what is now the Great Divide Basin with the new paradigm basic requirement that mountain range and continental divide uplift occurred while immense south-oriented floods flowed across them. Numerous divide crossings are notched into the continental divide segments now completely encircling the relatively flat-floored Great Divide Basin interior drainage area and divide crossings observed along each of the Great Divide Basin’s north, east, south, and west margins are described and interpreted first from the accepted paradigm perspective (using published literature interpretations to the extent possible) and second from the new paradigm perspective. The published literature does not mention most of the described divide crossings, much less provide explanations for their origins, perhaps because the accepted paradigm cannot satisfactorily explain those origins. In contrast the new paradigm successfully explains most if not all of the described (and observed, but undescribed) divide crossings, although the new paradigm requires a completely different middle and late Cenozoic regional geologic history than what most published regional geology literature describes.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84522088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. O. Odika, O. Anike, A. G. Onwuemesi, N. F. Odika, R. Ejeckam
Mining activities have long been recognized as a major source of environmental contamination associated with heavy metals and metalloids. This study evaluated the relationship between the occurrence and mining of lead-zinc sulphide ores at Ishiagu, Nigeria, and heavy metal and metalloid contamination. A comparative study of two zones in the area, with and without mining activities was also made Water, soil, stream sediment and ore samples were analyzed, after acid digestion, using atomic absorption spectrophotometer (AAS). The concentration levels of seven heavy metals and a metalloid namely Pb, Cu, Ni, Zn, Mn, Co, Cd and as were evaluated. While the highest concentration levels of As, Co and Pb (5.20 mg/l, 0.54 mg/l and 3.40 mg/l respectively) were found in water, those of Ni and Mn (2.26 mg/l and 5.48 mg/l respectively) occurred in soil. For Cu and Zn, highest levels of concentration (2.80 mg/l and 0.41 mg/l respectively) occurred in stream sediments. The variations in the concentration levels of these elements in varying geologic media (soil, water and sediment) indicate influence of rock types, human activities and media physiochemical characteristics. Geostatistical analyses using QQPlot, semivariogram and kriging showed normal distribution of these elements. Distribution and dispersion patterns of the heavy metals indicated increase in concentration levels in the local stream flow direction. Pb, Cu, As, Cd, Mn, and Ni concentrations had reached pollutant levels in water based on WHO standards, while Zn level is below. Since the local people use untreated surface water and groundwater for drinking and other domestic purposes, soil for farming and lead for cosmetics, long term exposure poses significant health risk for humans, animals and plants.
{"title":"Assessment of Environmental Geochemistry of Lead-Zinc Mining at Ishiagu Area, Lower Benue Trough, Southeastern Nigeria","authors":"P. O. Odika, O. Anike, A. G. Onwuemesi, N. F. Odika, R. Ejeckam","doi":"10.5539/esr.v9n1p31","DOIUrl":"https://doi.org/10.5539/esr.v9n1p31","url":null,"abstract":"Mining activities have long been recognized as a major source of environmental contamination associated with heavy metals and metalloids. This study evaluated the relationship between the occurrence and mining of lead-zinc sulphide ores at Ishiagu, Nigeria, and heavy metal and metalloid contamination. A comparative study of two zones in the area, with and without mining activities was also made Water, soil, stream sediment and ore samples were analyzed, after acid digestion, using atomic absorption spectrophotometer (AAS). The concentration levels of seven heavy metals and a metalloid namely Pb, Cu, Ni, Zn, Mn, Co, Cd and as were evaluated. While the highest concentration levels of As, Co and Pb (5.20 mg/l, 0.54 mg/l and 3.40 mg/l respectively) were found in water, those of Ni and Mn (2.26 mg/l and 5.48 mg/l respectively) occurred in soil. For Cu and Zn, highest levels of concentration (2.80 mg/l and 0.41 mg/l respectively) occurred in stream sediments. The variations in the concentration levels of these elements in varying geologic media (soil, water and sediment) indicate influence of rock types, human activities and media physiochemical characteristics. Geostatistical analyses using QQPlot, semivariogram and kriging showed normal distribution of these elements. Distribution and dispersion patterns of the heavy metals indicated increase in concentration levels in the local stream flow direction. Pb, Cu, As, Cd, Mn, and Ni concentrations had reached pollutant levels in water based on WHO standards, while Zn level is below. Since the local people use untreated surface water and groundwater for drinking and other domestic purposes, soil for farming and lead for cosmetics, long term exposure poses significant health risk for humans, animals and plants.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82416736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Groundwater resources in the floodplain wetlands of the White Volta River basin of Ghana is a major source of water for irrigation activities of communities living around and baseflow to sustain the flow of the river. Hydrology of the floodplain wetlands in the basin is complex, characterized by temporally variable storage volumes with erratic contribution to streamflow. For the continual usage of groundwater resources in the floodplains there is a need to study the form of interaction between the main river and floodplain wetlands. The study, adopted the PM-WIN (MODFLOW) model for simulating the interaction between the wetland and stream. Additionally, the lower boundary discharge output from the HYDRUS-1D model is the estimated recharge. This input quantifies the temporal and spatial variations in sub-surfaces discharges in the floodplain wetland. The simulation of the sub-surface hydraulic head of the wetland indicates a systematic variation relative to the White Volta River response to changes in the rainfall pattern. The interaction conditions vary from season to season with March, April, and May showing the least leakage (estimated values of 0.03 mm/day, 0.06 mm/day, and 0.15 mm/day, respectively) from the river into the floodplain wetland. Notably, the interaction between the wetland and the river as simulated is bidirectional. With most of the flow coming out from the river into the floodplain wetland, this condition persists in the months of August and September.
{"title":"Wetland River Flow Interaction in a Sedimentary Formation of the White Volta Basin of Ghana","authors":"B. Nyarko","doi":"10.5539/esr.v9n1p15","DOIUrl":"https://doi.org/10.5539/esr.v9n1p15","url":null,"abstract":"Groundwater resources in the floodplain wetlands of the White Volta River basin of Ghana is a major source of water for irrigation activities of communities living around and baseflow to sustain the flow of the river. Hydrology of the floodplain wetlands in the basin is complex, characterized by temporally variable storage volumes with erratic contribution to streamflow. For the continual usage of groundwater resources in the floodplains there is a need to study the form of interaction between the main river and floodplain wetlands. The study, adopted the PM-WIN (MODFLOW) model for simulating the interaction between the wetland and stream. Additionally, the lower boundary discharge output from the HYDRUS-1D model is the estimated recharge. This input quantifies the temporal and spatial variations in sub-surfaces discharges in the floodplain wetland. The simulation of the sub-surface hydraulic head of the wetland indicates a systematic variation relative to the White Volta River response to changes in the rainfall pattern. The interaction conditions vary from season to season with March, April, and May showing the least leakage (estimated values of 0.03 mm/day, 0.06 mm/day, and 0.15 mm/day, respectively) from the river into the floodplain wetland. Notably, the interaction between the wetland and the river as simulated is bidirectional. With most of the flow coming out from the river into the floodplain wetland, this condition persists in the months of August and September.","PeriodicalId":11486,"journal":{"name":"Earth Science Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77143773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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