Continuous snowfall caused natural disasters, called snow disasters here, frequently occur on the Qinghai-Tibetan Plateau of China in recent decades, and cause a large number of losses of animal husbandry and human property. However, their long-term changes are poorly known. Here we use historical records to place recent variations of snow disasters under the background of the past 200 years. There are 366 snow disasters events for the 1820–2009 period, of which 230 happen during 1980–2009. In particular, the count of each decadal events since 1980 is larger than any other time during the past two centuries.
{"title":"Unprecedented occurrence of snow disasters over the Qinghai-Tibetan Plateau since 1980","authors":"Qi Liu, Leilei He, Jing Zeng, Yetang Wang","doi":"10.3934/geosci.2021033","DOIUrl":"https://doi.org/10.3934/geosci.2021033","url":null,"abstract":"Continuous snowfall caused natural disasters, called snow disasters here, frequently occur on the Qinghai-Tibetan Plateau of China in recent decades, and cause a large number of losses of animal husbandry and human property. However, their long-term changes are poorly known. Here we use historical records to place recent variations of snow disasters under the background of the past 200 years. There are 366 snow disasters events for the 1820–2009 period, of which 230 happen during 1980–2009. In particular, the count of each decadal events since 1980 is larger than any other time during the past two centuries.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249170","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}
This article is part of the Economic Geography studies and deals with aspects related to intermodal logistics with particular reference to maritime transport of containers. Ports are historically one of the key infrastructures for the Italian economy. In recent decades, along with many industrial sectors that were once driving forces for the national economy, due to the lack of adequate strategic planning, it has failed to keep pace with the rapid changes imposed on all sectors involved in the process of globalization of the economic world, losing ground and competitiveness with respect to many competing realities, both in Northern Europe and in the Mediterranean basin itself [1]. Most of the other states of Mediterranean Europe are in similar conditions, but Italy is probably the one that has lost the most ground. In this situation of strong economic and social imbalance, the covid-19 epidemic has hit Italy before and dramatically and if it had not turned into a pandemic, hitting the rest of Europe and the planet and forcing the European institutions to launch, for the first time, concrete support measures for all, would probably have represented a fatal shock for the Italian economy. By elaborating the information on statistical data and projections available in numerous international publications on the transport economy and more specifically on logistics, taking into account the reasons for the successes and failures of similar realities to the Italian one, the study offers food for thought on what to do immediately and in the future, taking advantage of the unique and unrepeatable opportunity constituted by the economic initiatives for the post-pandemic recovery, to remedy the lost ground by returning an adequate role to our world of maritime and port transport which can also be a driving force for the territory behind, avoiding ending up on the edge of the evolved world.
{"title":"Ports and logistics: resilience, sustainability and new centrality in the post-pandemic perspective for Italy and EU Med ports","authors":"Stefania Palmentieri","doi":"10.3934/geosci.2021018","DOIUrl":"https://doi.org/10.3934/geosci.2021018","url":null,"abstract":"This article is part of the Economic Geography studies and deals with aspects related to intermodal logistics with particular reference to maritime transport of containers. Ports are historically one of the key infrastructures for the Italian economy. In recent decades, along with many industrial sectors that were once driving forces for the national economy, due to the lack of adequate strategic planning, it has failed to keep pace with the rapid changes imposed on all sectors involved in the process of globalization of the economic world, losing ground and competitiveness with respect to many competing realities, both in Northern Europe and in the Mediterranean basin itself [1]. Most of the other states of Mediterranean Europe are in similar conditions, but Italy is probably the one that has lost the most ground. In this situation of strong economic and social imbalance, the covid-19 epidemic has hit Italy before and dramatically and if it had not turned into a pandemic, hitting the rest of Europe and the planet and forcing the European institutions to launch, for the first time, concrete support measures for all, would probably have represented a fatal shock for the Italian economy. By elaborating the information on statistical data and projections available in numerous international publications on the transport economy and more specifically on logistics, taking into account the reasons for the successes and failures of similar realities to the Italian one, the study offers food for thought on what to do immediately and in the future, taking advantage of the unique and unrepeatable opportunity constituted by the economic initiatives for the post-pandemic recovery, to remedy the lost ground by returning an adequate role to our world of maritime and port transport which can also be a driving force for the territory behind, avoiding ending up on the edge of the evolved world.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249187","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}
Effective water resources management and water availability are under threat from multiple sources, including population growth, continuing urbanisation, and climate change. In this context, current water resources management requires a conceptual rethink, which is lacking in the urban water resources management literature. This paper addresses this gap by rethinking urban water resources management from a water-centric perspective. The paper discusses a conceptual rethinking of water resources management towards a water-centric water resources management system underpinned through combining nature-based solutions (NBS), green infrastructure, and water soft path approaches. It is concluded that through adopting a blend of NBS, green infrastructure, and water soft paths, a water-centric water resources management approach focused on achieving sustainable water availability can be developed. It is further concluded that in transitioning to a water-centric focused water resources management approach, water needs to be acknowledged as a key stakeholder in relation to guiding a transition to an effective holistic catchment-wide water-centric water resources management system focused on achieving sustainable water availability.
{"title":"Water resources management versus the world","authors":"J. Greenway","doi":"10.3934/geosci.2021035","DOIUrl":"https://doi.org/10.3934/geosci.2021035","url":null,"abstract":"Effective water resources management and water availability are under threat from multiple sources, including population growth, continuing urbanisation, and climate change. In this context, current water resources management requires a conceptual rethink, which is lacking in the urban water resources management literature. This paper addresses this gap by rethinking urban water resources management from a water-centric perspective. The paper discusses a conceptual rethinking of water resources management towards a water-centric water resources management system underpinned through combining nature-based solutions (NBS), green infrastructure, and water soft path approaches. It is concluded that through adopting a blend of NBS, green infrastructure, and water soft paths, a water-centric water resources management approach focused on achieving sustainable water availability can be developed. It is further concluded that in transitioning to a water-centric focused water resources management approach, water needs to be acknowledged as a key stakeholder in relation to guiding a transition to an effective holistic catchment-wide water-centric water resources management system focused on achieving sustainable water availability.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249358","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}
This paper examines the new perspectives on geographic education teaching contents through a foreign language. Covid-19 pandemic transformed teaching and learning environments and methods through the activation of distance learning in many schools around the world. In their new role of virtual classroom facilitators, teachers tried to offer an educational service through multiple multimedia resources and visual aids. The effects of the growing use of digital technologies in teaching methodologies show that these tools can be a valuable aid also for understanding the interdisciplinary nature of geography through the use of audiovisual materials and a vehicular language, that is a foreign language used as a medium of transmission of contents through CLIL approach. The research focuses on the advantages offered by the use of multimedia resources and movies to encourage interdisciplinary skills. According to many scholars, authentic materials and films in particular, boost students to acquire linguistic competences and a deeper understanding of geography.
{"title":"Multimedia resources and movies in the new perspectives on teaching geography through CLIL and ICT","authors":"Ester Cristina Lucia Tarricone","doi":"10.3934/geosci.2021036","DOIUrl":"https://doi.org/10.3934/geosci.2021036","url":null,"abstract":"This paper examines the new perspectives on geographic education teaching contents through a foreign language. Covid-19 pandemic transformed teaching and learning environments and methods through the activation of distance learning in many schools around the world. In their new role of virtual classroom facilitators, teachers tried to offer an educational service through multiple multimedia resources and visual aids. The effects of the growing use of digital technologies in teaching methodologies show that these tools can be a valuable aid also for understanding the interdisciplinary nature of geography through the use of audiovisual materials and a vehicular language, that is a foreign language used as a medium of transmission of contents through CLIL approach. The research focuses on the advantages offered by the use of multimedia resources and movies to encourage interdisciplinary skills. According to many scholars, authentic materials and films in particular, boost students to acquire linguistic competences and a deeper understanding of geography.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249363","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}
Cities are playing an increasingly important role in the development and growth of countries. A country's growth and prosperity is largely dependent on the efficient functioning of its cities. The reliance of countries on the ability of their cities to perform crucial central functions, for national growth, continues to rise. South Africa has a long-standing network of cities, towns and localities. These have developed and become hierarchised over the course of history during which population settlements and their distribution have been influenced by colonisation, segregation, industrialisation and globalisation. Since 1911, South Africa has undergone an extended phase of intense urban growth, with areas such as Johannesburg, Cape Town and eThekwini (Durban) agglomerating into dominating economic spaces. There are, however, no universally accepted, distinct criteria that constitute the general characteristics of secondary cities. The common assumption is that secondary cities are those cities that find themselves below the apex of what are considered primary cities. Furthermore, internationally, secondary cities appear to be considered as important catalysts for balanced and dispersed economic growth. In the South African context, the notion of what constitutes secondary cities is to a large extent underdeveloped. The aim of the paper is to appraise interconnected regional networks as a differentiated and novel outlook when determining secondary cities in South Africa. What is evident from the paper is that there are different potential alternatives with which to portray secondary cities.
{"title":"Differentiated outlook to portray secondary cities in South Africa","authors":"Andre DW Brand, J. Drewes, M. Campbell","doi":"10.3934/geosci.2021026","DOIUrl":"https://doi.org/10.3934/geosci.2021026","url":null,"abstract":"Cities are playing an increasingly important role in the development and growth of countries. A country's growth and prosperity is largely dependent on the efficient functioning of its cities. The reliance of countries on the ability of their cities to perform crucial central functions, for national growth, continues to rise. South Africa has a long-standing network of cities, towns and localities. These have developed and become hierarchised over the course of history during which population settlements and their distribution have been influenced by colonisation, segregation, industrialisation and globalisation. Since 1911, South Africa has undergone an extended phase of intense urban growth, with areas such as Johannesburg, Cape Town and eThekwini (Durban) agglomerating into dominating economic spaces. There are, however, no universally accepted, distinct criteria that constitute the general characteristics of secondary cities. The common assumption is that secondary cities are those cities that find themselves below the apex of what are considered primary cities. Furthermore, internationally, secondary cities appear to be considered as important catalysts for balanced and dispersed economic growth. In the South African context, the notion of what constitutes secondary cities is to a large extent underdeveloped. The aim of the paper is to appraise interconnected regional networks as a differentiated and novel outlook when determining secondary cities in South Africa. What is evident from the paper is that there are different potential alternatives with which to portray secondary cities.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249415","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}
The interpretation of dissipation tests from cone penetration tests (CPTU) in silt is often considered challenging due to the occurrence of an unknown degree of partial consolidation during penetration which may influence the results significantly. The main objective of the present study is to investigate the influence of penetration rate and hence partial consolidation in silt deposits on the interpretation of consolidation parameters. Rate dependency studies have been carried out so as to give recommendations on how to establish design consolidation parameters in silts and consider the effect of partial consolidation on the development of design parameters. A comprehensive field and laboratory research program has been conducted on a silt deposit in Halsen-Stj?rdal, Norway. Alongside performing various rate penetration CPTU tests with rates varying between 0.5 mm/s and 200 mm/s, dissipation tests were executed to analyze the consolidation behaviour of the soil deposit. Furthermore, a series of soil samples have been taken at the site to carry out high quality laboratory tests. Correction methods developed for non-standard dissipation tests could be successfully applied to the silt deposit indicating partial consolidation. The results revealed an underestimation of the coefficient of consolidation if partial consolidation is neglected in the analysis, emphasizing the importance of considering the drainage conditions at a silt site thoroughly. To study the drainage conditions of a soil deposit a recently proposed approach has been applied introducing a normalized penetration rate to differentiate between drained and undrained behaviour during penetration. It is suggested that a normalized penetration rate of less than 0.1–0.2 indicate drained behaviour while a normalized penetration rate above 40–50 indicate undrained behaviour. Finally, available dissipation test data from a Norwegian Geo-Test Site (NGTS) in Halden, Norway have been used to successfully verify the recommendations made for silts.
{"title":"Consolidation parameters in silts from varied rate CPTU tests","authors":"A. Bihs, M. Long, S. Nordal, P. Paniagua","doi":"10.3934/geosci.2021039","DOIUrl":"https://doi.org/10.3934/geosci.2021039","url":null,"abstract":"The interpretation of dissipation tests from cone penetration tests (CPTU) in silt is often considered challenging due to the occurrence of an unknown degree of partial consolidation during penetration which may influence the results significantly. The main objective of the present study is to investigate the influence of penetration rate and hence partial consolidation in silt deposits on the interpretation of consolidation parameters. Rate dependency studies have been carried out so as to give recommendations on how to establish design consolidation parameters in silts and consider the effect of partial consolidation on the development of design parameters. A comprehensive field and laboratory research program has been conducted on a silt deposit in Halsen-Stj?rdal, Norway. Alongside performing various rate penetration CPTU tests with rates varying between 0.5 mm/s and 200 mm/s, dissipation tests were executed to analyze the consolidation behaviour of the soil deposit. Furthermore, a series of soil samples have been taken at the site to carry out high quality laboratory tests. Correction methods developed for non-standard dissipation tests could be successfully applied to the silt deposit indicating partial consolidation. The results revealed an underestimation of the coefficient of consolidation if partial consolidation is neglected in the analysis, emphasizing the importance of considering the drainage conditions at a silt site thoroughly. To study the drainage conditions of a soil deposit a recently proposed approach has been applied introducing a normalized penetration rate to differentiate between drained and undrained behaviour during penetration. It is suggested that a normalized penetration rate of less than 0.1–0.2 indicate drained behaviour while a normalized penetration rate above 40–50 indicate undrained behaviour. Finally, available dissipation test data from a Norwegian Geo-Test Site (NGTS) in Halden, Norway have been used to successfully verify the recommendations made for silts.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249440","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}
The need for groundwater exploration in India has been increasing enormously, due to the non-judicial use of available water resources. The present study area is located between longitudes from 81°52′20.293′′ to 82°29′32.058′′ E and latitudes from 17°01′6.71′′ to 17°38′ 12.906′′ N in the Eastern Ghats mobile belt region of East Godavari district. The study area is characterized by a wide range of geological settings and high and irregular topographic features. The area is identified by Government as highly backward and Tribal people dwell here. For exploring good aquifer in the study area, the information of ten parameters together with geoelectrical resistivity data has been collected. Analytical Hierarchy Process (AHP) is used as the decision-making technique which uses the weights of different thematic layers (parameters) favorable for groundwater recharge, storage and location. Various thematic layers (parameters) of geology, geomorphology, soil, slope, lineament density, drainage density, groundwater level, Land use/Land cover, rainfall and coefficient of electrical anisotropy were considered in this analysis. A comprehensive groundwater prospect map has been prepared and validated with aquifer thickness map derived from the analysis of geoelectrical data. The entire study area has been classified into different potential zones of good, moderate and poor for groundwater exploration. The good groundwater potential zone is covering an area of 750.91 sqkm (28.4%) with aquifer thickness varying in the range 40–140 m, moderate potential zone encompasses 46.1% of the study area with an areal extent of 1220.33 sqkm and aquifer thickness is about 20–40 m. The remaining area of 24.5% is poor aquifer zone with thickness less than 20 m.
{"title":"Groundwater exploration in hard rock terrains of East Godavari district, Andhra Pradesh, India using AHP and WIO analyses together with geoelectrical surveys","authors":"P. V. Rao, M. Subrahmanyam, B. A. Raju","doi":"10.3934/geosci.2021015","DOIUrl":"https://doi.org/10.3934/geosci.2021015","url":null,"abstract":"The need for groundwater exploration in India has been increasing enormously, due to the non-judicial use of available water resources. The present study area is located between longitudes from 81°52′20.293′′ to 82°29′32.058′′ E and latitudes from 17°01′6.71′′ to 17°38′ 12.906′′ N in the Eastern Ghats mobile belt region of East Godavari district. The study area is characterized by a wide range of geological settings and high and irregular topographic features. The area is identified by Government as highly backward and Tribal people dwell here. For exploring good aquifer in the study area, the information of ten parameters together with geoelectrical resistivity data has been collected. Analytical Hierarchy Process (AHP) is used as the decision-making technique which uses the weights of different thematic layers (parameters) favorable for groundwater recharge, storage and location. Various thematic layers (parameters) of geology, geomorphology, soil, slope, lineament density, drainage density, groundwater level, Land use/Land cover, rainfall and coefficient of electrical anisotropy were considered in this analysis. A comprehensive groundwater prospect map has been prepared and validated with aquifer thickness map derived from the analysis of geoelectrical data. The entire study area has been classified into different potential zones of good, moderate and poor for groundwater exploration. The good groundwater potential zone is covering an area of 750.91 sqkm (28.4%) with aquifer thickness varying in the range 40–140 m, moderate potential zone encompasses 46.1% of the study area with an areal extent of 1220.33 sqkm and aquifer thickness is about 20–40 m. The remaining area of 24.5% is poor aquifer zone with thickness less than 20 m.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249114","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}
The Grand Ethiopian Renaissance Dam (GERD) in Ethiopia and High Aswan Dam (HAD) in Egypt both operate on the Nile River, independent of a governing international treaty or agreement. As a result, the construction of the GERD, the Earth's eighth largest dam, ignited a furious debate among Ethiopia, Sudan, and Egypt on its filling policies and long-term operation. Ethiopia and Egypt's stance on the Nile River's water resources, combined with a nationalistic policy debate on the GERD's filling policies and long-term operation, has severely affected progress toward reaching agreeable terms before the first round of GERD filling was completed. These three countries continue to debate on the terms of agreement for the second round of GERD filling, scheduled to start by July 2021. We examined the GERD filling strategy for five- and six-year terms using time series data for the periods 1979–1987 and 1987–1992 to combine analyses for dry and wet seasons and investigate the potential impacts of filling the GERD above the downstream HAD using four HAD starting water levels. A model calibrated using MIKE Hydro results shows that during both five- and six-year terms of future GERD filling, Egypt would not need to invoke the HAD's minimum operating level. We pursued a narrative approach that appeals to both a technical and non-technical readership, and our results show the urgent need for cooperation at both policy and technical levels to mitigate and adapt to future climate change through the development of climate-proof agreements. Moreover, the results call for the riparian countries to move away from the current nationalistic policy debate approach and pursue a more cooperative, economically beneficial, and climate adaptive approach.
{"title":"Beyond the implications of Grand Ethiopian Renaissance Dam filling policies","authors":"A. Yimere, E. Assefa","doi":"10.3934/geosci.2021019","DOIUrl":"https://doi.org/10.3934/geosci.2021019","url":null,"abstract":"The Grand Ethiopian Renaissance Dam (GERD) in Ethiopia and High Aswan Dam (HAD) in Egypt both operate on the Nile River, independent of a governing international treaty or agreement. As a result, the construction of the GERD, the Earth's eighth largest dam, ignited a furious debate among Ethiopia, Sudan, and Egypt on its filling policies and long-term operation. Ethiopia and Egypt's stance on the Nile River's water resources, combined with a nationalistic policy debate on the GERD's filling policies and long-term operation, has severely affected progress toward reaching agreeable terms before the first round of GERD filling was completed. These three countries continue to debate on the terms of agreement for the second round of GERD filling, scheduled to start by July 2021. We examined the GERD filling strategy for five- and six-year terms using time series data for the periods 1979–1987 and 1987–1992 to combine analyses for dry and wet seasons and investigate the potential impacts of filling the GERD above the downstream HAD using four HAD starting water levels. A model calibrated using MIKE Hydro results shows that during both five- and six-year terms of future GERD filling, Egypt would not need to invoke the HAD's minimum operating level. We pursued a narrative approach that appeals to both a technical and non-technical readership, and our results show the urgent need for cooperation at both policy and technical levels to mitigate and adapt to future climate change through the development of climate-proof agreements. Moreover, the results call for the riparian countries to move away from the current nationalistic policy debate approach and pursue a more cooperative, economically beneficial, and climate adaptive approach.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249226","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}
The Carboniferous Joggins Formation is known for its complete succession of fossil-rich, coal-bearing strata, deposited in a fluvial meanderbelt depositional setting. Hence, the Joggins Formation outcrop is an excellent analogue for studying the 2D geological complexities associated with meanderbelt systems. In this research, a conventional ground-penetrating radar system was tested with the intent of imaging near-surface, dipping, strata of the Joggins Formation (potentially with subsequent repeats as annual erosion provides new visual calibrations). The survey was unsuccessful in its primary goal, and for future reference we document the reasons here. However, the overlying near-surface angular unconformity was successfully imaged enabling mapping of the approximately 8 m of overlying glacial till. A successful outcome would have allowed observations from the 2D outcrop to be extended into 3D space and perhaps lead to an increased understanding of the small (e.g., bedform baffles and barriers) and large (e.g., channel bodies) scale architectural elements, meanderbelt geometry, and aspect ratios. The study comprises a 42-line, 3.46 km ground-penetrating radar survey using a Sensors and Software pulseEKKO Pro SmartCart system. It was combined with a real-time kinematic differential global positioning system for the georeferencing of survey lines. The 50 MHz antenna frequency, with a 1 m separation, was chosen to maximize the depth of penetration, while still maintaining a reasonable resolution. The results show that many of the lines are contaminated with diffraction hyperbolae, possibly caused from buried objects near or under the survey lines or surface objects near the survey lines. A total of thirteen unique radar reflectors are described and interpreted from this work. The thick clay-rich soil overlying the Joggins Formation probably contributed to significant signal attenuation and the nature of the Carboniferous strata (dip of the beds, pinching and swelling of the beds, bed thickness, etc.) also contributed to imaging difficulties.
石炭系约金斯组以其完整的富化石、含煤地层序列而闻名，沉积在河流曲流带沉积环境中。因此，Joggins组露头是研究与蜿蜒带系统相关的二维地质复杂性的极好模拟。在这项研究中，测试了传统的探地雷达系统，目的是对Joggins组近地表倾斜地层进行成像(后续可能会重复进行，因为每年的侵蚀提供了新的视觉校准)。该调查未能实现其主要目标，为了将来参考，我们在这里记录了原因。然而，对上覆的近地表角不整合进行了成功的成像，从而绘制了大约8米的上覆冰碛物。一个成功的结果将使二维露头的观测扩展到三维空间，并可能增加对小型(例如，河床挡板和障碍物)和大型(例如，河道体)规模建筑元素、曲流带几何形状和纵横比的理解。该研究包括42线，3.46公里的探地雷达测量，使用传感器和软件pulseEKKO Pro SmartCart系统。它与实时运动差分全球定位系统相结合，用于测量线的地理参考。选择50 MHz的天线频率，间隔1 m，以最大限度地提高穿透深度，同时仍然保持合理的分辨率。结果表明，许多线被衍射双曲线污染，这可能是由于测量线附近或以下的埋藏物体或测量线附近的表面物体造成的。从这项工作中，共描述和解释了13种独特的雷达反射器。Joggins组上覆较厚的富粘土层可能导致信号明显衰减，石炭系地层的性质(地层的倾角、地层的挤压和膨胀、地层厚度等)也导致成像困难。
{"title":"The technical challenges and outcomes of ground-penetrating radar: A site-specific example from Joggins, Nova Scotia","authors":"T. Kelly, G. Wach, D. O'Connor","doi":"10.3934/GEOSCI.2021002","DOIUrl":"https://doi.org/10.3934/GEOSCI.2021002","url":null,"abstract":"The Carboniferous Joggins Formation is known for its complete succession of fossil-rich, coal-bearing strata, deposited in a fluvial meanderbelt depositional setting. Hence, the Joggins Formation outcrop is an excellent analogue for studying the 2D geological complexities associated with meanderbelt systems. In this research, a conventional ground-penetrating radar system was tested with the intent of imaging near-surface, dipping, strata of the Joggins Formation (potentially with subsequent repeats as annual erosion provides new visual calibrations). The survey was unsuccessful in its primary goal, and for future reference we document the reasons here. However, the overlying near-surface angular unconformity was successfully imaged enabling mapping of the approximately 8 m of overlying glacial till. A successful outcome would have allowed observations from the 2D outcrop to be extended into 3D space and perhaps lead to an increased understanding of the small (e.g., bedform baffles and barriers) and large (e.g., channel bodies) scale architectural elements, meanderbelt geometry, and aspect ratios. The study comprises a 42-line, 3.46 km ground-penetrating radar survey using a Sensors and Software pulseEKKO Pro SmartCart system. It was combined with a real-time kinematic differential global positioning system for the georeferencing of survey lines. The 50 MHz antenna frequency, with a 1 m separation, was chosen to maximize the depth of penetration, while still maintaining a reasonable resolution. The results show that many of the lines are contaminated with diffraction hyperbolae, possibly caused from buried objects near or under the survey lines or surface objects near the survey lines. A total of thirteen unique radar reflectors are described and interpreted from this work. The thick clay-rich soil overlying the Joggins Formation probably contributed to significant signal attenuation and the nature of the Carboniferous strata (dip of the beds, pinching and swelling of the beds, bed thickness, etc.) also contributed to imaging difficulties.","PeriodicalId":43999,"journal":{"name":"AIMS Geosciences","volume":"92 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70249384","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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