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Geosciences, Volume 9, Issue 10 (October 2019) – 50 articles

Cover Story (view full-size image): The term “multihazard” indicates the individual or combined occurrence of several hazard phenomena in a specific area. The island of Santorini (Greece) was adopted to study slope stability due to possible multiple cascading effects caused by a sub-Plinian eruption, which represents the worst-case scenario for the island. The resulting map accounts for slope stability in a static and seismic condition and after ashfall deposition. The areas most likely to be affected by these different landslides were identified together with the hot spots (structure and infrastructures), where vulnerability analysis as well as risk mitigation strategies are required. View this paper.
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19 pages, 6069 KiB  
Article
Impact of Sparse Benthic Life on Seafloor Roughness and High-Frequency Acoustic Scatter
by Mischa Schönke, Lars Wiesenberg, Inken Schulze, Dennis Wilken, Alexander Darr, Svenja Papenmeier and Peter Feldens
Geosciences 2019, 9(10), 454; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100454 - 22 Oct 2019
Cited by 4 | Viewed by 2911
Abstract
Quantitative acoustic marine habitat mapping needs to consider the impact of macrobenthic organisms on backscatter data. However, the sensitivity of hydroacoustic systems to epibenthic life is poorly constrained. This study explores the impact of a benthic community with sparse abundance on seafloor microroughness [...] Read more.
Quantitative acoustic marine habitat mapping needs to consider the impact of macrobenthic organisms on backscatter data. However, the sensitivity of hydroacoustic systems to epibenthic life is poorly constrained. This study explores the impact of a benthic community with sparse abundance on seafloor microroughness and acoustic backscatter at a sandy seafloor in the German North Sea. A multibeam echo sounder survey was ground-truthed by lander measurements combining a laser line scanner with sub-mm resolution and broad-band acoustic transducers. Biotic and abiotic features and spatial roughness parameters were determined by the laser line scanner. At the same locations, acoustic backscatter was measured and compared with an acoustic scatter model utilizing the small-roughness perturbation approximation. Results of the lander experiments show that a coverage with epibenthic features of 1.6% increases seafloor roughness at spatial wavelengths between 0.005–0.03 m, increasing both spectral slope and intercept. Despite the fact that a strong impact on backscatter was predicted by the acoustic model based on measured roughness parameters, only a minor (1.1 dB) change of backscatter was actually observed during both the lander experiments and the ship-based acoustic survey. The results of this study indicate that benthic coverage of less than 1.6% is insufficient to be detected by current acoustic remote sensing. Full article
(This article belongs to the Special Issue Geological Seafloor Mapping)
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21 pages, 12005 KiB  
Article
Atmospheric Dynamics from Synoptic to Local Scale During an Intense Frontal Dust Storm over the Sistan Basin in Winter 2019
by Dimitris G. Kaskaoutis, Diana Francis, Alireza Rashki, Jean-Pierre Chaboureau and Umesh C. Dumka
Geosciences 2019, 9(10), 453; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100453 - 22 Oct 2019
Cited by 29 | Viewed by 4255
Abstract
The Sistan Basin has been recognized as one of the most active dust sources and windiest desert environments in the world. Although the dust activity in Sistan maximizes during the summer, rare but intense dust storms may also occur in the winter. This [...] Read more.
The Sistan Basin has been recognized as one of the most active dust sources and windiest desert environments in the world. Although the dust activity in Sistan maximizes during the summer, rare but intense dust storms may also occur in the winter. This study aims to elucidate the atmospheric dynamics related to dust emission and transport, dust-plume characteristics, and impacts on aerosol properties and air quality during an intense dust storm over Sistan in February 2019. The dust storm was initiated by strong northerly winds (~20 ms−1) associated with the intrusion of a cold front from high latitudes. The upper-level potential vorticity (PV)-trough evolved into a cut-off low in the mid and upper troposphere and initiated unstable weather over Afghanistan and northern Pakistan. At the surface, density currents emanating from deep convective clouds and further strengthened by downslope winds from the mountains, caused massive soil erosion. The passage of the cold front reduced the temperature by ~10 °C and increased the atmospheric pressure by ~10 hPa, while the visibility was limited to less than 200 m. The rough topography played a major role in modulating the atmospheric dynamics, wind field, dust emissions, and transport pathways. Meso-NH model simulates large amounts of columnar mass dust loading (> 20 g m−2) over Sistan, while the intense dust plume was mainly traveling below 2 km and increased the particulate matter (PM10) concentrations up to 1800 µg m−3 at Zabol. The dust storm was initially moving in an arc-shaped pathway over the Sistan Basin and then it spread away. Plumes of dust covered a large area in southwest Asia, reaching the northern Arabian Sea, and the Thar desert one to two days later, while they strongly affected the aerosol properties at Karachi, Pakistan, by increasing the aerosol optical depth (AOD > 1.2) and the coarse-mode fraction at ~0.7. Full article
(This article belongs to the Special Issue Observing Atmospheric Dynamics and Dust Activity)
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18 pages, 7900 KiB  
Article
The College Park, Maryland, Tornado of 24 September 2001
by Kenneth L. Pryor, Tyler Wawrzyniak and Da-Lin Zhang
Geosciences 2019, 9(10), 452; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100452 - 22 Oct 2019
Viewed by 3087
Abstract
The 24 September 2001 College Park, Maryland, tornado was a long-track and strong tornado that passed within a close range of two Doppler radars. It was the third in a series of three tornadoes associated with a supercell storm that developed in Stafford [...] Read more.
The 24 September 2001 College Park, Maryland, tornado was a long-track and strong tornado that passed within a close range of two Doppler radars. It was the third in a series of three tornadoes associated with a supercell storm that developed in Stafford County, Virginia, and initiated 3–4 km southwest of College Park and dissipated near Columbia, Howard County. The supercell tracked approximately 120 km and lasted for about 126 min. This study presents a synoptic and mesoscale overview of favorable conditions and forcing mechanisms that resulted in the severe convective outbreak associated with the College Park tornado. The results show many critical elements of the tornadic event, including a negative-tilted upper-level trough over the Ohio Valley, a jet stream with moderate vertical shear, a low-level warm, moist tongue of the air associated with strong southerly flow over south-central Maryland and Virginia, and significantly increased convective available potential energy (CAPE) during the late afternoon hours. A possible role of the urban heat island effects from Washington, DC, in increasing CAPE for the development of the supercell is discussed. Satellite imagery reveals the banded convective morphology with high cloud tops associated with the supercell that produced the College Park tornado. Operational WSR-88D data exhibit a high reflectivity “debris ball” or tornadic debris signature (TDS) within the hook echo, the evolution of the parent storm from a supercell structure to a bow echo, and a tornado cyclone signature (TCS). Many of the mesoscale features could be captured by contemporary numerical model analyses. This study concludes with a discussion of the effectiveness of the coordinated use of satellite and radar observations in the operational environment of nowcasting severe convection. Full article
(This article belongs to the Special Issue Meteorology, Climate and Severe Storms in the Mid Atlantic)
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17 pages, 33694 KiB  
Article
Development of a Landslide Early Warning System in Indonesia
by Rokhmat Hidayat, Samuel Jonson Sutanto, Alidina Hidayah, Banata Ridwan and Arif Mulyana
Geosciences 2019, 9(10), 451; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100451 - 22 Oct 2019
Cited by 28 | Viewed by 9372
Abstract
Landslides are one of the most disastrous natural hazards in Indonesia, in terms of number of fatalities and economic losses. Therefore, Balai Litbang Sabo (BLS) has developed a Landslide Early Warning System (LEWS) for Indonesia, based on a Delft–FEWS (Flood Early Warning System) [...] Read more.
Landslides are one of the most disastrous natural hazards in Indonesia, in terms of number of fatalities and economic losses. Therefore, Balai Litbang Sabo (BLS) has developed a Landslide Early Warning System (LEWS) for Indonesia, based on a Delft–FEWS (Flood Early Warning System) platform. This system utilizes daily precipitation data, a rainfall threshold method, and a Transient Rainfall Infiltration and Grid-based Regional Slope-stability model (TRIGRS) to predict landslide occurrences. For precipitation data, we use a combination of 1-day and 3-day cumulative observed and forecasted precipitation data, obtained from the Tropical Rainfall Measuring Mission (TRMM) and the Indonesian Meteorological Climatological and Geophysical Agency (BMKG). The TRIGRS model is used to simulate the slope stability in regions that are predicted to have a high probability of landslide occurrence. Our results show that the landslides, which occurred in Pacitan (28 November 2017) and Brebes regions (22 February 2018), could be detected by the LEWS from one to three days in advance. The TRIGRS model supports the warning signals issued by the LEWS, with a simulated factor of safety values lower than 1 in these locations. The ability of the Indonesian LEWS to detect landslide occurrences in Pacitan and Brebes indicates that the LEWS shows good potential to detect landslide occurrences a few days in advance. However, this system is still undergoing further developments for better landslide prediction. Full article
(This article belongs to the Section Natural Hazards)
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15 pages, 2535 KiB  
Article
Validation of Stratification-Driven Phytoplankton Biomass and Nutrient Concentrations in the Northeast Atlantic Ocean as Simulated by EC-Earth
by Nomikos Skyllas, Richard Bintanja, Anita G. J. Buma, Corina P. D. Brussaard, Matthias Gröger, Jenny Hieronymus and Willem H. van de Poll
Geosciences 2019, 9(10), 450; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100450 - 21 Oct 2019
Cited by 2 | Viewed by 7753
Abstract
We validated simulations of the Earth system model (ESM) EC-Earth-NEMO of present-day temperature, salinity, nutrient, and chlorophyll a profiles with in situ observations in the Northeast Atlantic Ocean (29–63º N). Simulations with standard parametrization (run 1) and improved parametrization of vertical mixing (run [...] Read more.
We validated simulations of the Earth system model (ESM) EC-Earth-NEMO of present-day temperature, salinity, nutrient, and chlorophyll a profiles with in situ observations in the Northeast Atlantic Ocean (29–63º N). Simulations with standard parametrization (run 1) and improved parametrization of vertical mixing (run 2) were compared. Run 1 showed shallower mixed layer depths (MLDs) in spring as compared to observations owing to lower salinities in the upper 200 m of the subpolar North Atlantic (>55º N). This coincided with a mismatch with observed timing and magnitude of the phytoplankton spring bloom. In contrast, the model performed well south of 55º N. Run 2 showed improved springtime MLD, phytoplankton dynamics, and nutrient distributions in the subpolar North Atlantic. Our study underlines the sensitivity of subpolar North Atlantic phytoplankton blooms to surface freshening, suggesting that future fresh-water inflow from Arctic and Greenland Ice sheet melting could significantly affect phytoplankton productivity. These findings contribute to the generic validation of the EC-Earth ESM and underline the need for rigorous validation of physics-biology links, in particular the sub polar North Atlantic where complex seasonal stratification/vertical mixing processes govern upper ocean phytoplankton productivity. Full article
(This article belongs to the Special Issue Ocean-Atmosphere Interaction)
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23 pages, 4628 KiB  
Article
Quantitative Hazard Assessment of Landslides Using the Levenburg–Marquardt Back Propagation Neural Network Method in a Pipeline Area
by Junnan Xiong, Jin Li, Hao Zhang, Ming Sun and Weiming Cheng
Geosciences 2019, 9(10), 449; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100449 - 21 Oct 2019
Cited by 1 | Viewed by 2847
Abstract
Pipelines are exposed to the severe threat of natural disasters, where the damage caused by landslides are particularly bad. Hence, in the route arrangement and maintenance management of pipeline projects, it is particularly important to evaluate the regional landslide hazards in advance. However, [...] Read more.
Pipelines are exposed to the severe threat of natural disasters, where the damage caused by landslides are particularly bad. Hence, in the route arrangement and maintenance management of pipeline projects, it is particularly important to evaluate the regional landslide hazards in advance. However, most models are based on the subjective determination of evaluation factors and index weights; this study establishes a quantitative hazard assessment model based on the location of historical landslides and the Levenberg–Marquardt Back Propagation (LM-BP) Neural Network model was applied to the pipeline area. We established an evaluation index system by analyzing the spatial patterns of single assessment factors and the mechanism of landslides. Then, different from previous studies, we built the standard sample matrix of the LM-BP neural network by using interpolation theory to avoid the serious influence of human factors on the hazard assessment. Finally, we used the standard sample matrix and the historical data to learn, train, test, and simulate future results. Our results showed 33 slopes with low hazard (accounting for 10.48% of the total number of slopes and corresponding to approximately 32.63 km2), 62 slopes with moderate hazard (accounting for 19.68% of the total number of slopes and corresponding to approximately 65.53 km2), 112 slopes with high hazard (accounting for 35.56% of the total number of slopes and corresponding to approximately 123.55 km2), and 108 slopes with extremely high hazard (accounting for 34.29% of the total number of slopes and corresponding to approximately 150.65 km2). Local spatial autocorrelation analysis indicated that there are significant “high–high” and “low–low” aggregation of landslide hazards in the pipeline area. By comparing the model results with the past landslides, new landslides and landslide potential points, its prediction capability and accuracy were confirmed. On the basis of the results, our study has developed effective risk prevention and mitigation strategies in mountain areas to promote pipeline safety. Full article
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17 pages, 12673 KiB  
Article
Application of EPS Geofoam to a Soil–Steel Bridge to Reduce Seismic Excitations
by Tomasz Maleska, Joanna Nowacka and Damian Beben
Geosciences 2019, 9(10), 448; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100448 - 21 Oct 2019
Cited by 30 | Viewed by 3546
Abstract
There have only been a limited number of analyses of soil–steel bridges under seismic and anthropogenic (rockburst) excitations. Rockbursts are phenomena similar to low-intensity natural earthquakes. They can be observed in Poland (Upper and Lower Silesia) as well as in many parts of [...] Read more.
There have only been a limited number of analyses of soil–steel bridges under seismic and anthropogenic (rockburst) excitations. Rockbursts are phenomena similar to low-intensity natural earthquakes. They can be observed in Poland (Upper and Lower Silesia) as well as in many parts of the world where coal and gas are mined. The influence of rockbursts and natural earthquakes on soil–steel bridges should be investigated because the ground motions caused by these two kinds of excitations differ. In the present paper, a non-linear analysis of a soil–steel bridge was carried out. Expanded polystyrene (EPS) geofoam blocks were used in a numerical model of the soil–steel bridge to buffer the seismic wave induced by a rockburst (coming from a coal mine) as well as a natural earthquake (El Centro record). The analyzed soil–steel bridge had two closed pipe arches in its cross-section. The span of the shells was 4.40 m and the height of the shells was 2.80 m. The numerical analysis was conducted using the DIANA program based on the finite element method (FEM). The paper presents the FEM results of a 3D numerical study of a soil–steel bridge both with and without the application of the EPS geofoam under seismic excitations. The obtained results can be interesting to bridge engineers and scientists dealing with the design and analysis of bridges situated in seismic and mining areas. Full article
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13 pages, 4445 KiB  
Article
Seismic Imaging of the Mesozoic Bedrock Relief and Geological Structure under Quaternary Sediment Cover: The Bolmin Syncline (SW Holy Cross Mountains, Poland)
by Bartosz Owoc, Artur Marciniak, Jan Dzierżek, Sebastian Kowalczyk and Mariusz Majdański
Geosciences 2019, 9(10), 447; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100447 - 18 Oct 2019
Cited by 6 | Viewed by 3844
Abstract
The clear and detailed images of geological structures that can be obtained by seismic methods are one of the main drivers of their popularity in geological research. The quality of final geophysical images and models relies strongly on the amount of data that [...] Read more.
The clear and detailed images of geological structures that can be obtained by seismic methods are one of the main drivers of their popularity in geological research. The quality of final geophysical images and models relies strongly on the amount of data that goes into them. Analysing several complementary seismic datasets allow an improved interpretation. Responding to this challenge, this article proposed an optimal combination of geophysical methods for near-surface applications. Multi-channel analysis of surface waves, first-arrival travel-time tomography, and ground-penetrating radar were the key supports for standard reflection seismic imaging. Ease of use and fast and cheap acquisition are some of the advantages of the mentioned methods. Considering that all recorded wave fields required minimal additional processing while offering a significant improvement in the final stack, it was worth the extra effort. Thanks to that, the better-estimated velocity filed allowed high quality images to be obtained up to 200 m. The Mesozoic bedrock was a distinct and very strong reflector in the resulting reflection seismic imaging. There was also a clearly visible depression of the horizon corresponding to erosion or a structure (syncline). Deeper, it was possible to track two or even four detachments of faulting origin. Full article
(This article belongs to the Section Geophysics)
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22 pages, 5367 KiB  
Article
Deformation Modeling of Flexible Pavement in Expansive Subgrade in Texas
by Asif Ahmed, MD Sahadat Hossain, Pratibha Pandey, Anuja Sapkota and Boon Thian
Geosciences 2019, 9(10), 446; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100446 - 18 Oct 2019
Cited by 10 | Viewed by 3414
Abstract
The tendency of expansive subgrade soil to undergo swelling and shrinkage with the change in moisture has a significant impact on the performance of the pavement. The repeated cycles of wet and dry periods throughout a year lead to considerable stress concentration in [...] Read more.
The tendency of expansive subgrade soil to undergo swelling and shrinkage with the change in moisture has a significant impact on the performance of the pavement. The repeated cycles of wet and dry periods throughout a year lead to considerable stress concentration in the pavement subgrade soil. Such stress concentrations leads to the formation of severe pavement cracks. The objective of the research is to develop a prediction model to estimate the deformation of pavement over expansive subgrade. Two pavement sites—one farm to market road and one state highway—were monitored regularly using moisture and temperature sensors along with rain gauges. Additionally, geophysical testing was performed to obtain a continuous profile of the subgrade soil over time. Topographical surveying and horizontal inclinometer readings were taken to determine pavement deformation. The field monitoring data resulted in a maximum movement up to 80 mm in the farm to market road, and almost 38 mm in the state highway. The field data were statistically evaluated to develop a deformation prediction model. The validation of the model indicated that only a fraction of the deformation was reflected by seasonal variation, while inclusion of rainfall events in the equation significantly improved the model. Furthermore, the prediction model also incorporated the effects of change in temperature and resistivity values. The generated model could find its application in predicting pavement deformation with respect to rainfall at any time of the year. Full article
(This article belongs to the Special Issue Behavior of Expansive Soils and its Shrinkage Cracking)
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15 pages, 2051 KiB  
Article
Quantification of Modelling Uncertainties in Bridge Scour Risk Assessment under Multiple Flood Events
by Alonso Pizarro and Enrico Tubaldi
Geosciences 2019, 9(10), 445; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100445 - 18 Oct 2019
Cited by 25 | Viewed by 3107
Abstract
Local scour is a dynamic process evolving during the lifetime of bridges as a result of the changes in hydrologic and hydraulic conditions. Current approaches for scour risk assessment are generally based on the evaluation of the equilibrium scour depth for a flood [...] Read more.
Local scour is a dynamic process evolving during the lifetime of bridges as a result of the changes in hydrologic and hydraulic conditions. Current approaches for scour risk assessment are generally based on the evaluation of the equilibrium scour depth for a flood event with a prefixed return period. The temporal evolution of the bridge-pier scour process is usually disregarded, by assuming that equilibrium conditions are always attained, regardless of the flood properties. However, recent studies have highlighted the importance of accounting for the contribution of multiple flood events and their exact hydrograph shape. This study aims at quantifying the epistemic uncertainty related to the modelling of the temporal evolution of scour under multiple consecutive flood events in clear-water conditions. A simple numerical case study is considered, using a Markovian framework to describe probabilistically the progression of scour. Well-known time-dependent scour models are used to estimate the temporal evolution of the scour-depth under each flood hydrograph, and the scour estimates are compared with those obtained using widely employed equilibrium scour formulas. Results show that the expected scour depth is influenced by the parameters used to describe the flood hydrograph and that the probability distribution of the scour depth is highly sensitive to the choice of the time-dependent scour model. The uncertainty in the scour estimation stemming from the formula adopted in this study for describing the temporal evolution of the scour depth can be higher than those related to the formula adopted for equilibrium scour. Full article
(This article belongs to the Special Issue Impacts of Compound Hydrological Hazards or Extremes)
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19 pages, 8715 KiB  
Article
Effect of Communication Regarding Dam Operation on the Evacuation of Residents: A Case Study of the 2018 Inundation of the Hijikawa River in Japan
by Isao Nakamura and Chiho Morioka
Geosciences 2019, 9(10), 444; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100444 - 18 Oct 2019
Cited by 2 | Viewed by 2860
Abstract
Communication on the operation of a dam is crucial in evacuating residents before downstream flooding occurs. This paper examines the effect of communication regarding dam operation on evacuation, studying the case of the 2018 flooding of the Hijikawa River in Japan. After confirming [...] Read more.
Communication on the operation of a dam is crucial in evacuating residents before downstream flooding occurs. This paper examines the effect of communication regarding dam operation on evacuation, studying the case of the 2018 flooding of the Hijikawa River in Japan. After confirming the communication process and the messages of warning, we conducted a questionnaire survey of affected residents. The findings of the survey are as follows. (1) The discharge warnings issued by dam operators had no effect, because few people heard the warnings and even those who heard them were not inclined to evacuate. (2) Accepting the notifications from dam operators, local governments issued evacuation instructions. These instructions promoted evacuation. The most effective trigger of evacuation was route alerting by the volunteer fire corps. Information from dam operators induced the issuing of evacuation instructions, which activated the route alerting, and the information therefore indirectly promoted evacuation. (3) The Public Warning System operating on mobile phones had a certain effect in disseminating evacuation instructions where the system was used. (4) The messages issued here had insufficient specificity and clarity. A flood simulation considering the discharge flow of a dam needs to be conducted in addressing this issue. Full article
(This article belongs to the Special Issue Flood Frequency and Inundation Modelling)
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7 pages, 207 KiB  
Editorial
Gas Hydrate: Environmental and Climate Impacts
by Umberta Tinivella, Michela Giustiniani, Ivan de la Cruz Vargas Cordero and Atanas Vasilev
Geosciences 2019, 9(10), 443; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100443 - 18 Oct 2019
Cited by 8 | Viewed by 3104
Abstract
This Special Issue reports research spanning from the analysis of indirect data, modelling, laboratory and geological data confirming the intrinsic multidisciplinarity of the gas hydrate studies. The study areas are (1) Arctic, (2) Brazil, (3) Chile and (4) the Mediterranean region. The results [...] Read more.
This Special Issue reports research spanning from the analysis of indirect data, modelling, laboratory and geological data confirming the intrinsic multidisciplinarity of the gas hydrate studies. The study areas are (1) Arctic, (2) Brazil, (3) Chile and (4) the Mediterranean region. The results furnished an important tessera of the knowledge about the relationship of a gas hydrate system with other complex natural phenomena such as climate change, slope stability and earthquakes, and human activities. Full article
(This article belongs to the Special Issue Gas Hydrate: Environmental and Climate Impacts)
21 pages, 5233 KiB  
Article
Assessment of the Carbon Stock in Pine Plantations in Southern Spain through ALS Data and K-Nearest Neighbor Algorithm Based Models
by Miguel A. Navarrete-Poyatos, Rafael M. Navarro-Cerrillo, Miguel A. Lara-Gómez, Joaquín Duque-Lazo, Maria de los Angeles Varo and Guillermo Palacios Rodriguez
Geosciences 2019, 9(10), 442; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100442 - 17 Oct 2019
Cited by 9 | Viewed by 3578
Abstract
Accurate estimation of forest biomass to enable the mapping of forest C stocks over large areas is of considerable interest nowadays. Airborne laser scanning (ALS) systems bring a new perspective to forest inventories and subsequent biomass estimation. The objective of this research was [...] Read more.
Accurate estimation of forest biomass to enable the mapping of forest C stocks over large areas is of considerable interest nowadays. Airborne laser scanning (ALS) systems bring a new perspective to forest inventories and subsequent biomass estimation. The objective of this research was to combine growth models used to update old inventory data to a reference year, low-density ALS data, and k-nearest neighbor (kNN) algorithm Random Forest to conduct biomass inventories aimed at estimating the C sequestration capacity in large Pinus plantations. We obtained a C stock in biomass (Wt-S) of 12.57 Mg·ha−1, ranging significantly from 19.93 Mg·ha−1 for P. halepensis to 49.05 Mg·ha−1 for P. nigra, and a soil organic C stock of the composite soil samples (0–40 cm) ranging from 20.41 Mg·ha−1 in P. sylvestris to 37.32 Mg·ha−1 in P. halepensis. When generalizing these data to the whole area, we obtained an overall C-stock value of 48.01 MgC·ha−1, ranging from 23.96 MgC·ha−1 for P. halepensis to 58.09 MgC·ha−1 for P. nigra. Considering the mean value of the on-site C stock, the study area sustains 1,289,604 Mg per hectare (corresponding to 4,732,869 Mg CO2), with a net increase of 4.79 Mg·ha−1·year−1. Such C cartography can help forest managers to improve forest silviculture with regard to C sequestration and, thus, climate change mitigation. Full article
(This article belongs to the Special Issue Properties, Developments and Processes of Soils as Carbon Sinks)
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26 pages, 6414 KiB  
Article
Managing the Agri-Food System of Watersheds to Combat Coastal Eutrophication: A Land-to-Sea Modelling Approach to the French Coastal English Channel
by Josette Garnier, Philippe Riou, Romain Le Gendre, Antsiva Ramarson, Gilles Billen, Philippe Cugier, Mathilde Schapira, Sylvain Théry, Vincent Thieu and Alain Ménesguen
Geosciences 2019, 9(10), 441; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100441 - 16 Oct 2019
Cited by 18 | Viewed by 3366
Abstract
The continental coastal waters of the Eastern Channel, from Normandy to Hauts-de-France, are subject to the major influence of unbalanced nutrient inputs from inflowing rivers. Several episodes of harmful algal blooms (HABs) compromising fishing and shellfish farming activities have been observed at the [...] Read more.
The continental coastal waters of the Eastern Channel, from Normandy to Hauts-de-France, are subject to the major influence of unbalanced nutrient inputs from inflowing rivers. Several episodes of harmful algal blooms (HABs) compromising fishing and shellfish farming activities have been observed at the coast. For a better understanding of how the land-to-sea aquatic continuum functions, the GRAFS-RIVERSTRAHLER river biogeochemical model was implemented to cover the watersheds of 11 rivers flowing into this area (including the Seine) and chained with the ecological marine ECO-MARS3D model, applied to the French Northern coastal zone. Human activities strongly impact on the functioning of coastal ecosystems. Specifically, for these fertile soils of Northern France, intensive agricultural nitrogen (N) deliveries in excess over silica (Si) and phosphorus (P), essentially of diffuse origin, are potentially responsible for coastal eutrophication. Phosphorous is today equally supplied by diffuse and point sources, after a drastic reduction of inputs from wastewater treatment plants since the 2000s, and is better balanced regarding Si, as shown by the indicators of coastal eutrophication potential (P-ICEP versus N-ICEP). However, despite this drastic P reduction, HABs still appear repeatedly. Exploration of several scenarios of agro-food chain reorganization shows that (i) further progress in urban wastewater treatment to fully comply with current European regulations will not result in a significant reduction of nutrient fluxes to the sea, hence including HABs, and (ii) radical structural changes in agriculture, based on generalization of long and diversified organic crop rotations, reconnection of crop and livestock farming and changes in the human diet have the capacity to significantly reduce nutrient flows, coastal eutrophication and HABs. Full article
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15 pages, 12111 KiB  
Article
Dipole and Convergent Single-Well Thermal Tracer Tests for Characterizing the Effect of Flow Configuration on Thermal Recovery
by Jérôme de La Bernardie, Olivier Bour, Nicolas Guihéneuf, Eliot Chatton, Laurent Longuevergne and Tanguy Le Borgne
Geosciences 2019, 9(10), 440; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100440 - 15 Oct 2019
Cited by 4 | Viewed by 2441
Abstract
Experimental characterization of thermal transport in fractured media through thermal tracer tests is crucial for environmental and industrial applications such as the prediction of geothermal system efficiency. However, such experiments have been poorly achieved in fractured rock due to the low permeability and [...] Read more.
Experimental characterization of thermal transport in fractured media through thermal tracer tests is crucial for environmental and industrial applications such as the prediction of geothermal system efficiency. However, such experiments have been poorly achieved in fractured rock due to the low permeability and complexity of these media. We have thus little knowledge about the effect of flow configuration on thermal recovery during thermal tracer tests in such systems. We present here the experimental set up and results of several single-well thermal tracer tests for different flow configurations, from fully convergent to perfect dipole, achieved in a fractured crystalline rock aquifer at the experimental site of Plœmeur (H+ observatory network). The monitoring of temperature using Fiber-Optic Distributed Temperature Sensing (FO-DTS) associated with appropriate data processing allowed to properly highlight the heat inflow in the borehole and to estimate temperature breakthroughs for the different tests. Results show that thermal recovery is mainly controlled by advection processes in convergent flow configuration while in perfect dipole flow field, thermal exchanges with the rock matrix are more important, inducing lower thermal recovery. Full article
(This article belongs to the Special Issue Subsurface Thermography and the Use of Temperature in Geosciences)
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4 pages, 179 KiB  
Editorial
A Two-Way Avenue of Knowledge: An Editorial for the Special Issue “Geoscience of the Built Environment 2019 Edition”
by Carlos Alves
Geosciences 2019, 9(10), 439; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100439 - 14 Oct 2019
Viewed by 1611
Abstract
This editorial presents the papers published in the 2019 edition of this series of special issues in the context of the contribution of geological studies to the development of knowledge on the built environment (namely materials) and in the opposite sense, that is [...] Read more.
This editorial presents the papers published in the 2019 edition of this series of special issues in the context of the contribution of geological studies to the development of knowledge on the built environment (namely materials) and in the opposite sense, that is the potential contribution of studies of the Built Environment to geoscientific knowledge. This is discussed considering the major framework of the Anthropocene. Full article
13 pages, 814 KiB  
Article
A New Geodetic Method of Examination of Geometrical Conditions of a Crane Bridge
by Daria Filipiak-Kowszyk, Waldemar Kamiński and Karolina Makowska
Geosciences 2019, 9(10), 438; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100438 - 11 Oct 2019
Cited by 1 | Viewed by 2223
Abstract
Safety is one of the key aspects related to crane-based material transport. In order to ensure safe crane operation and material transport, it is necessary to meet certain geometrical conditions. The authors addressed the geometrical conditions of a crane bridge, a substantial crane [...] Read more.
Safety is one of the key aspects related to crane-based material transport. In order to ensure safe crane operation and material transport, it is necessary to meet certain geometrical conditions. The authors addressed the geometrical conditions of a crane bridge, a substantial crane component. The paper presents the method to compute displacement components of points on the top of a bridge crane relative to their design position. Theoretical considerations presented in the paper have been verified on simulated data. Keeping in mind the proper operation of a crane bridge, the authors proposed in the analyses the use of geometrical relations (perpendicular and parallel character) between end carriages and girders, not previously included in the available literature. The obtained results show that the presented method may be successfully applied to check the geometry of a crane bridge. Full article
(This article belongs to the Special Issue Geosciences and their use in the field of Civil Engineering)
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18 pages, 8537 KiB  
Article
Comparison of Earthquake-Triggered Landslide Inventories: A Case Study of the 2015 Gorkha Earthquake, Nepal
by Sansar Raj Meena and Sepideh Tavakkoli Piralilou
Geosciences 2019, 9(10), 437; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100437 - 10 Oct 2019
Cited by 23 | Viewed by 4503
Abstract
Despite landslide inventories being compiled throughout the world every year at different scales, limited efforts have been made to critically compare them using various techniques or by different investigators. Event-based landslide inventories indicate the location, distribution, and detected boundaries of landslides caused by [...] Read more.
Despite landslide inventories being compiled throughout the world every year at different scales, limited efforts have been made to critically compare them using various techniques or by different investigators. Event-based landslide inventories indicate the location, distribution, and detected boundaries of landslides caused by a single event, such as an earthquake or a rainstorm. Event-based landslide inventories are essential for landslide susceptibility mapping, hazard modeling, and further management of risk mitigation. In Nepal, there were several attempts to map landslides in detail after the Gorkha earthquake. Particularly after the main event on 25 April 2015, researchers around the world mapped the landslides induced by this earthquake. In this research, we compared four of these published inventories qualitatively and quantitatively using different techniques. Two principal methodologies, namely the cartographical degree of matching and frequency area distribution (FAD), were optimized and applied to evaluate inventory maps. We also showed the impact of using satellite imagery with different spatial resolutions on the landslide inventory generation by analyzing matches and mismatches between the inventories. The results of our work give an overview of the impact of methodology selection and outline the limitations and advantages of different remote sensing and mapping techniques for landslide inventorying. Full article
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21 pages, 4618 KiB  
Article
Monitoring Groundwater Change in California’s Central Valley Using Sentinel-1 and GRACE Observations
by Zhen Liu, Pang-Wei Liu, Elias Massoud, Tom G Farr, Paul Lundgren and James S. Famiglietti
Geosciences 2019, 9(10), 436; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100436 - 09 Oct 2019
Cited by 49 | Viewed by 6838
Abstract
The San Joaquin Valley and Tulare basins in California’s Central Valley have intensive agricultural activity and groundwater demand that has caused significant subsidence and depletion of water resources in the past. We measured groundwater pumping-induced land subsidence in the southern Central Valley from [...] Read more.
The San Joaquin Valley and Tulare basins in California’s Central Valley have intensive agricultural activity and groundwater demand that has caused significant subsidence and depletion of water resources in the past. We measured groundwater pumping-induced land subsidence in the southern Central Valley from March 2015 to May 2017 using Sentinel-1 interferometric synthetic aperture radar (InSAR) data. The InSAR measurements provided fine spatial details of subsidence patterns and displayed a superposition of secular and seasonal variations that were coherent across our study region and correlated with precipitation variability and changes in freshwater demand. Combining InSAR and Global Positioning System (GPS) data, precipitation, and in situ well records showed a broad scale slowdown/cessation of long term subsidence in the wetter winter of 2017, likely reflecting the collective response of the Central Valley aquifer system to heavier-than-usual precipitation. We observed a very good temporal correlation between the Gravity Recovery and Climate Experiment (GRACE) satellite groundwater anomaly (GWA) variation and long-term subsidence records, regardless of local hydrogeology and mechanical properties. This indicates the subsidence from satellite geodesy is a very useful indicator for tracking groundwater storage change. With the continuing acquisition of Sentinel-1 and other satellites, we anticipate decadal-scale subsidence records with a spatial resolution of tens to hundreds of meters will be available in the near future to be combined with basin-averaged GRACE measurements to improve our estimate of time-varying groundwater change. Full article
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22 pages, 3302 KiB  
Article
Leaching Behavior of As, Pb, Ni, Fe, and Mn from Subsurface Marine and Nonmarine Depositional Environment in Central Kanto Plain, Japan
by Sushmita Hossain, Takashi Ishiyama, Shoichi Hachinohe and Chiaki T. Oguchi
Geosciences 2019, 9(10), 435; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100435 - 08 Oct 2019
Cited by 4 | Viewed by 2865
Abstract
The leaching behavior of arsenic (As), lead (Pb), nickel (Ni), iron (Fe), and manganese (Mn) was investigated from subsurface core sediment of marine and nonmarine depositional environments in central Kanto Plain, Japan. A four-step sequential extraction technique was adopted to determine the chemical [...] Read more.
The leaching behavior of arsenic (As), lead (Pb), nickel (Ni), iron (Fe), and manganese (Mn) was investigated from subsurface core sediment of marine and nonmarine depositional environments in central Kanto Plain, Japan. A four-step sequential extraction technique was adopted to determine the chemical speciation, potential mobility, and bioavailability of metals under natural conditions in variable depositional environments. In addition, a correlation of these properties with pore water and total metal content was carried out. The concentration of As in pore water was found to be 2–3 times higher than the permissible limit (10 µg/L) for drinking water and leachate in fluvial, transitional, and marine environments. The trend of potential mobile fractions of As, Pb, and Ni showed Fe–Mn oxide bound > carbonate bound > ion exchangeable bound > water soluble in the fluvial environment. However, in the marine environment, it showed Fe–Mn oxide bound > water soluble > carbonate bound > ion exchangeable bound for As. The leaching of As in this fluvial environment is due to the organic matter-mediated, reductive dissolution of Fe–Mn oxide bound, where Mn is the scavenger. The amount of total content of As and sulfur (S) in transitional sediment reflects an elevated level of leachate in pore water, which is controlled by S reduction. However, the leaching of As in marine sediment is controlled by pH and organic matter content. Full article
(This article belongs to the Special Issue Marine Sediments and Marine Environments)
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20 pages, 1311 KiB  
Article
Cross the Border: Participative Integrated Approach to Sustainable Tourism Planning
by Daniela Angelina Jelinčić, Sanja Tišma, Zoltán Lantos and Iva Tolić
Geosciences 2019, 9(10), 434; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100434 - 08 Oct 2019
Cited by 4 | Viewed by 3425
Abstract
Cross-border areas and cross-border cooperation are one of the priorities of the EU policy. Those areas, often rich in recreational, cultural and natural resources provide a great potential for the development of sustainable tourism. The article analyzes the tourism in the Croatian-Hungarian (HR-HU) [...] Read more.
Cross-border areas and cross-border cooperation are one of the priorities of the EU policy. Those areas, often rich in recreational, cultural and natural resources provide a great potential for the development of sustainable tourism. The article analyzes the tourism in the Croatian-Hungarian (HR-HU) cross-border area under the assumption that different interventions can influence the perception of tourists and contribute to the realization of the full potential of the area. The method applied in the analysis is the gravity model. The results obtained by the model were tested with online in-depth interviews with three experts having backgrounds in entrepreneurship, decision making and the non-governmental sector, and focus groups, consisting of 31 experts in the field, show that altogether 72% of the tourists cross the border during a trip to the HR-HU border regions. Almost half of the respondents plan and organize programs during the trip. The main sources of collecting information about a trip are friends, family members and acquaintances, while 80% of the respondents also use at least one online tool for planning of the trip. In order to improve tourism indicators in the Croatian-Hungarian cross-border area, development of a cross-border online platform is being envisaged that would integrate different services and attractions, collect and utilize data, being the most important new raw material, thus opening a completely new space for virtual tourism. Full article
(This article belongs to the Special Issue Sustainable Tourism,Geography and Spatial Planning)
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13 pages, 2347 KiB  
Article
The Origin of Dissolved Sulphate in the Thermal Waters of Budapest Inferred from Stable S and O Isotopes
by István Fórizs, Viktória Rita Szabó, József Deák, Stanisław Hałas, Andrzej Pelc, Andrzej Trembaczowski and Árpád Lorberer
Geosciences 2019, 9(10), 433; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100433 - 08 Oct 2019
Cited by 3 | Viewed by 2796
Abstract
The thermal waters produced by wells and springs from the Buda Thermal Karst in Budapest and its surroundings are rich in dissolved sulphate. Radiocarbon ages indicate that waters of T >45 ℃ were infiltrated during the Ice Age (more than 11 thousand years [...] Read more.
The thermal waters produced by wells and springs from the Buda Thermal Karst in Budapest and its surroundings are rich in dissolved sulphate. Radiocarbon ages indicate that waters of T >45 ℃ were infiltrated during the Ice Age (more than 11 thousand years ago), on the higher elevations of the Buda-Pilis Hills, whereas waters of lower temperatures were infiltrated during the Holocene. For the origin of dissolved sulphate, two hypotheses can be set up: (1) the dissolved sulphate originates from the oxidation of the sulphide (pyrite) of Oligocene Clay Formation; (2) it is the dissolution product of the sulphate minerals (gypsum and anhydrite) of older carbonaceous rocks (limestone and dolomite). The isotopically stable sulphur composition of the dissolved sulphate in the thermal water (δ34S = 9.7‰ to 17.7‰) indicates its marine origin, so likely it dissolved from the older Permian evaporites. Full article
(This article belongs to the Special Issue Isotope Geochemistry of Meteoric Waters)
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19 pages, 2385 KiB  
Article
Geochemical Signatures of Paleoclimate Changes in the Sediment Cores from the Gloria and Snorri Drifts (Northwest Atlantic) over the Holocene-Mid Pleistocene
by Liudmila L. Demina, Ekaterina A. Novichkova, Alexander P. Lisitzin and Nina V. Kozina
Geosciences 2019, 9(10), 432; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100432 - 05 Oct 2019
Cited by 10 | Viewed by 5094
Abstract
A multiproxy study of the sediment cores taken from the Snorri Drift, formed under the influence of the Iceland–Scotland bottom contour current, and from the Gloria Drift, located southward Greenland at the boundary of Irminger and Labrador Seas, was performed. This area undergoes [...] Read more.
A multiproxy study of the sediment cores taken from the Snorri Drift, formed under the influence of the Iceland–Scotland bottom contour current, and from the Gloria Drift, located southward Greenland at the boundary of Irminger and Labrador Seas, was performed. This area undergoes a variable mixing of polar waters with the warm North Atlantic current, whose intensity and direction seemed to change dramatically with the alteration of warming and cooling periods during the six marine isotope stages MIS 1-6. The relative age of this core does not exceed 190,000 cal yr BP; the average sedimentation rate was 1.94 and 2.45 cm/kyr in the Gloria and Snorri Drifts core respectively. In both the cores, the sediment records showed the downcore co-variation of ice-rafted debris (IRD); and terrigenous elements, such as Si, Al, Ti, Cr, and Zr, were revealed; their values were clearly higher in the glacial periods (MIS 2, 4, and 6) compared to interglacials (MIS 1, 3, and 5). The downcore rhythmic distributions of these elements, as well as Al/Si, Ti/Al, Fe/Al ratios exhibit an opposite trend with that of δ18O values, biogenic components (CaCO3, BioSiO2), and Si/Fe and Mn/Fe ratios. Full article
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16 pages, 1415 KiB  
Review
Landfill Impacts on the Environment—Review
by Magdalena Daria Vaverková
Geosciences 2019, 9(10), 431; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100431 - 03 Oct 2019
Cited by 149 | Viewed by 56511
Abstract
Waste management (WM) is a demanding undertaking in all countries, with important implications for human health, environmental preservation, sustainability and circular economy. The method of sanitary landfilling for final disposal of waste remains a generally accepted and used method but the available scientific [...] Read more.
Waste management (WM) is a demanding undertaking in all countries, with important implications for human health, environmental preservation, sustainability and circular economy. The method of sanitary landfilling for final disposal of waste remains a generally accepted and used method but the available scientific evidence on the waste-related environmental and health effects is not conclusive. Comparative studies of various WM methods (landfilling, incineration, composting etc.) show that among the municipal solid waste (MSW) treatment and disposal technological options, sanitary landfilling or open dumping is popular in most countries because of the relative low cost and low-technical requirement. The European Union (EU) Directive on waste landfills has introduced specific goals for reducing the volume of disposed waste and very strict requirements for landfilling and landfill sites. Evaluation of the impact of landfills on the environment is a crucial topic in the literature and has received increased attention recently, given growing environmental concerns. The main goal of this survey was to conduct a comprehensive assessment of possible impacts of MSW landfills on the environment. The main conclusion of the overall assessment of the literature is that the disposal of MSW in landfills entails a number of environmental risks but with respect to the current situation and rich style of living adopted in industrially developed countries, the idea of WM systems functioning without landfilling—at least in the foreseeable future within one generation—seems to be somewhat unreal. The results also provided important information of landfills as a source of environmental risk. Results of this research may have an important impact on landfill management and the disposal of waste. From the literature review, it is evident that even if high levels of waste avoidance, reuse and recycling are achieved, some waste materials will always need to be forwarded for disposal. Full article
(This article belongs to the Special Issue Waste Management and Environmental Remediation)
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14 pages, 12836 KiB  
Article
Location Modeling of Final Palaeolithic Sites in Northern Germany
by Wolfgang B. Hamer, Daniel Knitter, Sonja B. Grimm, Benjamin Serbe, Berit Valentin Eriksen, Oliver Nakoinz and Rainer Duttmann
Geosciences 2019, 9(10), 430; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100430 - 03 Oct 2019
Cited by 7 | Viewed by 4174
Abstract
Location modeling, both inductive and deductive, is widely used in archaeology to predict or investigate the spatial distribution of sites. The commonality among these approaches is their consideration of only spatial effects of the first order (i.e., the interaction of the locations with [...] Read more.
Location modeling, both inductive and deductive, is widely used in archaeology to predict or investigate the spatial distribution of sites. The commonality among these approaches is their consideration of only spatial effects of the first order (i.e., the interaction of the locations with the site characteristics). Second-order effects (i.e., the interaction of locations with each other) are rarely considered. We introduce a deductive approach to investigating such second-order effects using linguistic hypotheses about settling behavior in the Final Palaeolithic. A Poisson process was used to simulate a point distribution using expert knowledge of two distinct hunter–gatherer groups, namely, reindeer hunters and elk hunters. The modeled points and point densities were compared with the actual finds. The G-, F-, and K-function, which allow for the identification of second-order effects of varying intensity for different periods, were applied. The results reveal differences between the two investigated groups, with the reindeer hunters showing location-related interaction patterns, indicating a spatial memory of the preferred locations over an extended period of time. Overall, this paper shows that second-order effects occur in the geographical modeling of archaeological finds and should be taken into account by using approaches such as the one presented in this paper. Full article
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10 pages, 2701 KiB  
Article
Comparison of Different Measurement Techniques as Methodology for Surveying and Monitoring Stainless Steel Chimneys
by Karol Daliga and Zygmunt Kurałowicz
Geosciences 2019, 9(10), 429; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100429 - 02 Oct 2019
Cited by 3 | Viewed by 3023
Abstract
The measurement of a chimney axis is an engineering geodesy task. These measurements allow to assess the technical condition of chimneys and are usually carried out for reinforced concrete chimneys. When measuring high chimneys, the main problem may be the need to go [...] Read more.
The measurement of a chimney axis is an engineering geodesy task. These measurements allow to assess the technical condition of chimneys and are usually carried out for reinforced concrete chimneys. When measuring high chimneys, the main problem may be the need to go a long distance to take a measurement. The surface of the chimney can also be problematic because it can absorb so much light from the range finder that total station reflectorless measurement or laser scanning will not be possible or will be affected by significant error. Chimneys made of stainless steel are also used today. They are not as high as reinforced concrete chimneys, but measuring them using reflectorless total stations or laser scanning can also be problematic. Problems arise from the reflective surface of these chimneys. The article presents a comparison of measurement results of a stainless steel chimney fragment obtained from total station measurement and laser scanning. Similarities and differences in the obtained axis of this chimney fragment are presented. Full article
(This article belongs to the Special Issue Geodesy and Geomatics Engineering)
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17 pages, 7794 KiB  
Article
Coupled Analysis of Desiccation Cracking in Unsaturated Soils through a Non-Local Mathematical Formulation
by Shashank Menon and Xiaoyu Song
Geosciences 2019, 9(10), 428; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100428 - 02 Oct 2019
Cited by 22 | Viewed by 3366
Abstract
The formation of desiccation cracks in unsaturated soils as a discontinuity phenomenon can compromise the integrity of civil infrastructure on unsaturated soils. Because of the singularity at such discontinuities, the mathematical modeling of desiccation cracking is challenging. In this study, we apply a [...] Read more.
The formation of desiccation cracks in unsaturated soils as a discontinuity phenomenon can compromise the integrity of civil infrastructure on unsaturated soils. Because of the singularity at such discontinuities, the mathematical modeling of desiccation cracking is challenging. In this study, we apply a coupled nonlocal peridynamic poroelastic framework to model desiccation cracking in unsaturated soils. The soil skeleton is modeled by a nonlocal peridynamic elastic solid. A peridynamic equivalence of the generalized Darcy’s law is utilized to model unsaturated fluid flow. Cracking is determined by a critical stretch criterion between material points as well as an energy criterion. We present numerical simulations of desiccation cracking in soil bars and thin soil discs for one-dimensional cracking and two-dimensional cracking networks, respectively. The numerical results have demonstrated that the proposed nonlocal mathematical framework is a promising and robust method for modeling desiccation cracking in unsaturated soils. Full article
(This article belongs to the Special Issue Behavior of Expansive Soils and its Shrinkage Cracking)
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19 pages, 3377 KiB  
Article
Seismic Vulnerability and Old Towns. A Cost-Based Programming Model
by Salvatore Giuffrida, Maria Rosa Trovato, Chiara Circo, Vittoria Ventura, Margherita Giuffrè and Valentina Macca
Geosciences 2019, 9(10), 427; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100427 - 02 Oct 2019
Cited by 24 | Viewed by 2745
Abstract
Vulnerability is a big issue for small inland urban centres, which are exposed to the risk of depopulation. In the climate of the centre-northern part of Italy, and in the context of the recent concentration of a high number of earthquakes in that [...] Read more.
Vulnerability is a big issue for small inland urban centres, which are exposed to the risk of depopulation. In the climate of the centre-northern part of Italy, and in the context of the recent concentration of a high number of earthquakes in that area, seismic vulnerability can become the determinant cause of the final abandonment of a small town. In some Italian regions, as well as in Emilia Romagna, municipalities are implementing seismic vulnerability reduction policies based on the Emergency Limit Condition, which has become a basic point of reference for ordinary land planning. This study proposes an approach to seismic vulnerability reduction based on valuation planning for implementation within the general planning framework of the Faentina Union, a group of five small towns located in the southwestern part of the Province of Ravenna, Italy. This approach consists of three main stages: knowledge—the typological, constructive, and technological descriptions of the buildings, specifically concerning their degree of vulnerability; interpretation—analysis with the aim of outlining a range of hypotheses with respect to damage in case of a prospective earthquake; and planning—the identification of the courses of action intended to meaningfully reduce the vulnerability of buildings. This stage includes a cost modelling tool aimed at defining the trade-off between the extension and the intensity of the vulnerability reduction works, given the budget. Full article
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21 pages, 5318 KiB  
Article
Six Years Temperature Monitoring Using Fibre-Optic Sensors in a Bioreactor Landfill
by Sylvain Moreau, Thomas Jouen, Julien Grossin-Debattista, Simon Loisel, Laurent Mazéas and Rémi Clément
Geosciences 2019, 9(10), 426; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100426 - 02 Oct 2019
Cited by 4 | Viewed by 2521
Abstract
Temperature is a relevant physical parameter to monitor the biodegradation phases of waste mass. Irstea and the landfill operator SAS Les Champs Jouault have been collaborating since 2011 to study the temporal evolution and the spatial distribution of temperature in a municipal solid [...] Read more.
Temperature is a relevant physical parameter to monitor the biodegradation phases of waste mass. Irstea and the landfill operator SAS Les Champs Jouault have been collaborating since 2011 to study the temporal evolution and the spatial distribution of temperature in a municipal solid waste cell. Using distributed temperature sensing technology, optical fibres were installed in waste mass composed of household waste and industrial waste at different depths during the landfilling period. Temperature distributions were studied from 2012 until 2018 and the same evolutions are observed everywhere with more or less important amplitude variations depending on the location of the measurement point. When landfilled, the waste is at ambient temperature and a significant increase is observed the following year due to the exothermic impact of the aerobic biodegradation phase before a slower decrease during the anaerobic biodegradation phase over several years. Thermal parameters of the waste mass and the surrounding soil, as well as the heat generation function, are calculated using numerical simulation to reproduce the temperature evolution and its spatial distribution. The study of the long-term temperature evolution makes it possible to evaluate the favourable period during which the deposit cell will be in optimal conditions to promote the biodegradation waste processes. Full article
(This article belongs to the Special Issue Subsurface Thermography and the Use of Temperature in Geosciences)
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21 pages, 5411 KiB  
Article
Estimations of Fracture Surface Area Using Tracer and Temperature Data in Geothermal Fields
by Anna Suzuki, Fuad Ikhwanda, Aoi Yamaguchi and Toshiyuki Hashida
Geosciences 2019, 9(10), 425; https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences9100425 - 01 Oct 2019
Cited by 9 | Viewed by 2925
Abstract
Reinjection is crucial for sustainable geothermal developments. In order to predict thermal performances due to cold-water injection, a method was developed to estimate effective fracture surface areas (i.e., heat transfer areas). Tracer response curves at production wells are analyzed to determine flow rates [...] Read more.
Reinjection is crucial for sustainable geothermal developments. In order to predict thermal performances due to cold-water injection, a method was developed to estimate effective fracture surface areas (i.e., heat transfer areas). Tracer response curves at production wells are analyzed to determine flow rates and pore volumes, and the fracture surface areas are optimized by short-term thermal response curves. Because the method erases fracture apertures from the equation by combining mass and heat transfer equations, the fracture surfaces can be analyzed without assuming that the fracture shape is a parallel plate. The estimation method was applied to two geothermal field datasets: One involved an artificially created reservoir, and the other involved a naturally occurring reservoir. The estimated heat transfer areas are reasonable in the field geometries. Once the fracture surface area is estimated, the future temperature change and power generation can be predicted. This can provide a simple and quick method to design reinjection strategies. Full article
(This article belongs to the Special Issue Subsurface Thermography and the Use of Temperature in Geosciences)
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