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Geosciences, Volume 8, Issue 4 (April 2018)

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Cover Story (view full-size image) Geomorphic parameters, derived from seabed terrain models can be used to classify seabed types. [...] Read more.
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Open AccessArticle Characteristic and Mixing Mechanisms of Thermal Fluid at the Tampomas Volcano, West Java, Using Hydrogeochemistry, Stable Isotope and 222Rn Analyses
Geosciences 2018, 8(4), 103; https://doi.org/10.3390/geosciences8040103
Received: 12 December 2017 / Revised: 10 February 2018 / Accepted: 6 March 2018 / Published: 21 March 2018
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Abstract
The Tampomas Volcano is a Quaternary volcano located on Java Island and controlled by a west-northwest–east-southeast (WNW-ESE) regional fault trend. This regional structure acts as conduits for the hydrothermal fluids to ascend from a deeper system toward the surface and, in the end,
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The Tampomas Volcano is a Quaternary volcano located on Java Island and controlled by a west-northwest–east-southeast (WNW-ESE) regional fault trend. This regional structure acts as conduits for the hydrothermal fluids to ascend from a deeper system toward the surface and, in the end, mix with groundwater. In this research, water geochemistry, gas chemistry and isotopes 2H, 18O and 13C were used to explore the subsurface fluid characteristics and mixing mechanisms of the hydrothermal fluids with groundwater. In addition to those geochemical methods, soil-gas and dissolved 222Rn observations were performed to understand the geological control of fluid chemistry. Based on the analytical results, the hydrothermal system of Tampomas is only developed at the northeastern flank of the volcano, which is mainly controlled by NE-SW structures as deep fluid conduits, while the Cimalaka Caldera Rim around Sekarwangi act as the boundary flow of the system. This system is also categorized as an “intermediate temperature system” wherein fluid is derived from the interaction between the volcanic host-rock at 170 ± 10 °C mixed with trace organic gas input from sedimentary formation; afterwards, the fluid flows laterally and is diluted with groundwater near the surface. Soil-gas and dissolved 222Rn confirm that these permeable zones are effective conduits for the ascending thermal fluids. It is found that NE faults carry higher trace elements from the deeper system, while the circular feature of the Caldera Rim acts as the boundary of the hydrothermal system. Full article
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Open AccessArticle Drought Prediction System for Central Europe and Its Validation
Geosciences 2018, 8(4), 104; https://doi.org/10.3390/geosciences8040104
Received: 16 January 2018 / Revised: 15 February 2018 / Accepted: 15 March 2018 / Published: 21 March 2018
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Abstract
In recent years, two drought monitoring systems have been developed in the Czech Republic based on the SoilClim and AVISO soil moisture models. The former is run by Mendel University and Global Change Research Institute (CAS), while the latter, by the Czech Hydrometeorological
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In recent years, two drought monitoring systems have been developed in the Czech Republic based on the SoilClim and AVISO soil moisture models. The former is run by Mendel University and Global Change Research Institute (CAS), while the latter, by the Czech Hydrometeorological Institute. SoilClim is based more on real soil properties and aimed primarily at agriculture, while AVISO complements the system with more theoretical presumptions about soil, showing, rather, climatological potential. Both soil moisture models were complemented by forecasts on a daily basis, taking meteorological inputs from NWP (Numerical Weather Prediction) models and thus giving short- to mid-range outlooks up to 9 days ahead. Validation of the soil moisture and drought intensity prediction was performed and is presented in this article showing its prediction reliability and potential. In the analysis, we focus mainly on the past year, 2017. The tool has strong predictive power for soil moisture and drought intensity so it is suitable for farmers who need to make decisions about irrigation and production activities. The presented system is fully functional and can be applied in the coming years. Full article
(This article belongs to the Special Issue Drought Monitoring and Prediction)
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Open AccessArticle Integrated Reservoir Characterization Study of the McKee Formation, Onshore Taranaki Basin, New Zealand
Geosciences 2018, 8(4), 105; https://doi.org/10.3390/geosciences8040105
Received: 10 January 2018 / Revised: 26 February 2018 / Accepted: 13 March 2018 / Published: 21 March 2018
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Abstract
The Late Eocene onshore McKee Formation is a producing reservoir rock in Taranaki Basin, New Zealand. An integrated petrophysical, sedimentological, and petrographical study was conducted to evaluate the reservoir characteristics of the McKee sandstone. A petrographic study of the McKee Formation classified the
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The Late Eocene onshore McKee Formation is a producing reservoir rock in Taranaki Basin, New Zealand. An integrated petrophysical, sedimentological, and petrographical study was conducted to evaluate the reservoir characteristics of the McKee sandstone. A petrographic study of the McKee Formation classified the sandstone as arkose based on the Pettijohn classification. Porosity analysis showed predominantly intergranular porosity, as elucidated by the thin section photomicrographs. The good reservoir quality of McKee sandstone was suggested to be the result of the presence of secondary dissolution pores interconnected with the primary intergranular network. Mineral dissolution was found to be the main process that enhanced porosity in all the studied wells. On the other hand, the presence of clay minerals, cementation, and compaction were identified as the main porosity-reducing agents. These features, however, were observed to occur only locally, thus having no major impact on the overall reservoir quality of the McKee Formation. For a more detailed reservoir characterization, well log analysis was also applied in the evaluation of the McKee Formation. The result of the well log analysis showed that the average porosity ranged from 11.8% to 15.9%, with high hydrocarbon saturation ranging from 61.8% to 89.9% and clay volume content ranging from 14.9 to its highest value of 34.5%. Based on the well log analysis, the derived petrophysical and reservoir parameters exhibited good porosity, low clay content, and high hydrocarbon saturation, which indicates that the McKee Formation is a promising reservoir. Full article
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Open AccessArticle Primary Producers and Anthropic Signs Related to the Flood Plain Soils of the Tablas de Daimiel Wetland
Geosciences 2018, 8(4), 106; https://doi.org/10.3390/geosciences8040106
Received: 26 January 2018 / Revised: 14 March 2018 / Accepted: 14 March 2018 / Published: 22 March 2018
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Abstract
In the Tablas de Daimiel National Park (TDNP) wetlands, a semi-arid wetland system in Spain that is of international importance, it is believed that pollutants from a variety of sources accumulate. In the study reported here, we evaluated soils from the flooded part
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In the Tablas de Daimiel National Park (TDNP) wetlands, a semi-arid wetland system in Spain that is of international importance, it is believed that pollutants from a variety of sources accumulate. In the study reported here, we evaluated soils from the flooded part of this wetland in an effort to establish relationships between the abundance/structure of microbial communities (mainly cyanobacteria) and certain soil properties (redox potential, dissolved oxygen, organic matter, soil reaction, electrical conductivity, calcium carbonate, total nitrogen, soluble phosphorus and total phosphorus). This objective was achieved by establishing one transect from the entrance to exit of the flood plain, including sampling from potentially polluted sites. Substantial variations between sampling sites were found in soil in terms of salinity, dissolved oxygen (DO), organic matter (OM), total phosphorus (TP) and nitrogen (TN). The presence of primary producers was more evident in contaminated samples. In addition to calcium, high levels of oxidizable organic matter, traces of dissolved oxygen, and considerable amounts of nitrate and phosphates probably stimulated the growth of cyanobacteria, these latter characteristics can be explained as being due to the influence of wastewaters from urban, industrial and agricultural activities that run off directly into this unique wetland. In the future it will be necessary to understand the synergic effects of other soil properties. Full article
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Open AccessArticle A Transient ElectroMagnetic (TEM) Method Survey in North-Central Coast of Crete, Greece: Evidence of Seawater Intrusion
Geosciences 2018, 8(4), 107; https://doi.org/10.3390/geosciences8040107
Received: 18 January 2018 / Revised: 14 March 2018 / Accepted: 19 March 2018 / Published: 22 March 2018
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Abstract
Seawater intrusion into near-shore aquifers is one of the main environmental problems that affect Mediterranean islands. Crete is the biggest and most populated island of Greece, characterized by limited surface waters and strong dependence on groundwater sources as the primary source of natural
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Seawater intrusion into near-shore aquifers is one of the main environmental problems that affect Mediterranean islands. Crete is the biggest and most populated island of Greece, characterized by limited surface waters and strong dependence on groundwater sources as the primary source of natural water supply for extensive agricultural activity and human use. Freshwater demand in Crete has increased notably the last decades. The Geropotamos aquifer is located on the north-central coast of Crete and freshwater management is in a delicate balance with saltwater at coastal areas of the aquifer due to the scarce precipitation and high evaporation as well as the intense over exploitation of the groundwater resources. The geological setting of the study area is considered complex and the local tectonic regime is characterized by two sets of faults orientated NW-SE and NE-SW. Investigation of the aquifer using a survey grid of 1179 Transient ElectroMagnetic soundings (TEM) in 372 sites, has resulted in 1D models, and 2D/3D visualization of geoelectric structures, depicting the zones of salination of groundwater in the aquifer. Geological mapping, hydro-lithological data and geochemical analysis of 24 water samples (22 boreholes and 2 springs) are in agreement with results obtained from TEM soundings, supporting our interpretation that the aquifer is degraded by saline intrusion which likely occurs along fractures in a fault zone, emphasising the critical role of fracture pathways in salination problems of coastal aquifers. Full article
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Open AccessArticle Interpretation of the Factors Defining Groundwater Quality of the Site Subjected to the Wildfire of 2007 in Ilia Prefecture, South-Western Greece
Geosciences 2018, 8(4), 108; https://doi.org/10.3390/geosciences8040108
Received: 18 February 2018 / Revised: 17 March 2018 / Accepted: 19 March 2018 / Published: 23 March 2018
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Abstract
The present study examines the factors that define groundwater quality of a site subjected to the wildfire of 2007 in Ilia Prefecture, Peloponnese. This wildfire was the most severe in Greece in the last decade. An extensive sampling was carried out three months
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The present study examines the factors that define groundwater quality of a site subjected to the wildfire of 2007 in Ilia Prefecture, Peloponnese. This wildfire was the most severe in Greece in the last decade. An extensive sampling was carried out three months after the fire. Ninety-nine samples were analyzed in the Hydrogeology Laboratory of University of Patras for major and trace elements. The groundwater samples were classified into three hydrochemical types: Ca-HCO3, Ca-HCO3-SO4 and Ca-Na-HCO3. The hydrochemical results, processed using R-type factor analysis, resulted in a three-factor model that did not indicate any wildfire impact. The values of pH and electrical conductivity ranged between the expected levels for the area. The most abundant cations (Ca, Mg, Na, K) and trace elements (Mn, Zn, Cu, Cd, Pb, V) in the ash, occurred in the majority of the groundwater samples at concentrations below the potable limits set by the European Council. The concentrations of NO3, NO2, NH4+, phosphates, and sulphates, where present, were attributed to agricultural land uses of the area. No hydrochemical disturbances were found that could indicate a fire-retardant effect. It is likely that the prominent thickness of the unsaturated zone, of the granular aquifers that prevail in the area, limited the infiltration of the elements and trace elements usually found in abundance in fire ash. Full article
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Open AccessArticle The Impact of Acoustic Imaging Geometry on the Fidelity of Seabed Bathymetric Models
Geosciences 2018, 8(4), 109; https://doi.org/10.3390/geosciences8040109
Received: 4 March 2018 / Revised: 20 March 2018 / Accepted: 22 March 2018 / Published: 24 March 2018
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Abstract
Attributes derived from digital bathymetric models (DBM) are a powerful means of analyzing seabed characteristics. Those models however are inherently constrained by the method of seabed sampling. Most bathymetric models are derived by collating a number of discrete corridors of multibeam sonar data.
[...] Read more.
Attributes derived from digital bathymetric models (DBM) are a powerful means of analyzing seabed characteristics. Those models however are inherently constrained by the method of seabed sampling. Most bathymetric models are derived by collating a number of discrete corridors of multibeam sonar data. Within each corridor the data are collected over a wide range of distances, azimuths and elevation angles and thus the quality varies significantly. That variability therefore becomes imprinted into the DBM. Subsequent users of the DBM, unfamiliar with the original acquisition geometry, may potentially misinterpret such variability as attributes of the seabed. This paper examines the impact on accuracy and resolution of the resultant derived model as a function of the imaging geometry. This can be broken down into the range, angle, azimuth, density and overlap attributes. These attributes in turn are impacted by the sonar configuration including beam widths, beam spacing, bottom detection algorithms, stabilization strategies, platform speed and stability. Superimposed over the imaging geometry are residual effects due to imperfect integration of ancillary sensors. As the platform (normally a surface vessel), is moving with characteristic motions resulting from the ocean wave spectrum, periodic residuals in the seafloor can become imprinted that may again be misinterpreted as geomorphological information. Full article
(This article belongs to the Special Issue Marine Geomorphometry)
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Open AccessArticle Three-Dimensional Growth of Flexural Slip Fault-Bend and Fault-Propagation Folds and Their Geomorphic Expression
Geosciences 2018, 8(4), 110; https://doi.org/10.3390/geosciences8040110
Received: 6 February 2018 / Revised: 13 March 2018 / Accepted: 16 March 2018 / Published: 24 March 2018
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Abstract
The three-dimensional growth of fault-related folds is known to be an important process during the development of compressive mountain belts. However, comparatively little is known concerning the manner in which fold growth is expressed in topographic relief and local drainage networks. Here we
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The three-dimensional growth of fault-related folds is known to be an important process during the development of compressive mountain belts. However, comparatively little is known concerning the manner in which fold growth is expressed in topographic relief and local drainage networks. Here we report results from a coupled kinematic and surface process model of fault-related folding. We consider flexural slip fault-bend and fault-propagation folds that grow in both the transport and strike directions, linked to a surface process model that includes bedrock channel development and hillslope diffusion. We investigate various modes of fold growth under identical surface process conditions and critically analyse their geomorphic expression. Fold growth results in the development of steep forelimbs and gentler, wider backlimbs resulting in asymmetric drainage basin development (smaller basins on forelimbs, larger basins on backlimbs). However, topographies developed above fault-propagation folds are more symmetric than those developed above fault-bend folds as a result of their different forelimb kinematics. In addition, the surface expression of fault-bend and fault-propagation folds depends both on the slip distribution along the fault and on the style of fold growth. When along-strike plunge is a result of slip events with gently decreasing slip towards the fault tips (with or without lateral propagation), large plunge-panel drainage networks are developed at the expense of backpanel (transport-opposing) and forepanel (transport-facing) drainage basins. In contrast, if the fold grows as a result of slip events with similar displacements along strike, plunge-panel drainage networks are poorly developed (or are transient features of early fold growth) and restricted to lateral fold terminations, particularly when the number of propagation events is small. The absence of large-scale plunge-panel drainage networks in natural examples suggests that the latter mode of fold growth may be more common. The advective component of deformation (implicit in kink-band migration models of fault-bend and fault-propagation folding) exerts a strong control on drainage basin development. In particular, as drainage lengthens with fold growth, more linear, parallel drainage networks are developed as compared to the dendritic patterns developed above simple uplifting structures. Over the 1 Ma of their development the folds modelled here only attain partial topographic equilibrium, as new material is continually being advected through active axial surfaces on both fold limbs and faults are propagating in both the transport and strike directions. We also find that the position of drainage divides at the Earth’s surface has a complex relationship to the underlying fold axial surface locations. Full article
(This article belongs to the Special Issue Tectonics and Morphodynamics)
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Open AccessArticle Geochemistry and Structure of Krakatoa Volcano in the Sunda Strait, Indonesia
Geosciences 2018, 8(4), 111; https://doi.org/10.3390/geosciences8040111
Received: 12 February 2018 / Revised: 23 March 2018 / Accepted: 23 March 2018 / Published: 26 March 2018
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Abstract
The violent eruption of Krakatoa Volcano located in the Sunda Strait, Indonesia, in 1883 represents one of the deadliest eruptions in human civilization. Although lots of data have been reported, the trajectory of the subducted slab and the upper mantle structure beneath this
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The violent eruption of Krakatoa Volcano located in the Sunda Strait, Indonesia, in 1883 represents one of the deadliest eruptions in human civilization. Although lots of data have been reported, the trajectory of the subducted slab and the upper mantle structure beneath this volcano are still rather poorly known. We combined geochemical data, major, trace and rare earth elements with seismic tomograms to characterize the deep structure of Krakatoa Volcano at the junction of Sumatra and Java subduction systems. Geochemical data are in agreement with the partial melting of mantle wedge in these subduction systems, based on previous studies, and this conclusion is also supported by inferences from P-wave tomographic model. Whereas, the tomographic image of S-wave suggests that subducted slab has been intruded by hot material of mantle upwelling. The presence of both partial melting of mantle wedge and mantle upwelling in the upper mantle might be caused by the thinning of subducted slab beneath Krakatoa Volcano. Full article
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Open AccessArticle Economic Risk Evaluation in Urban Flooding and Instability-Prone Areas: The Case Study of San Giovanni Rotondo (Southern Italy)
Geosciences 2018, 8(4), 112; https://doi.org/10.3390/geosciences8040112
Received: 20 December 2017 / Revised: 19 March 2018 / Accepted: 28 March 2018 / Published: 30 March 2018
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Abstract
Estimating economic losses caused on buildings and other civil engineering works due to flooding events is often a difficult task. The accuracy of the estimate is affected by the availability of detailed data regarding the return period of the flooding event, vulnerability of
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Estimating economic losses caused on buildings and other civil engineering works due to flooding events is often a difficult task. The accuracy of the estimate is affected by the availability of detailed data regarding the return period of the flooding event, vulnerability of exposed assets, and type of economy run in the affected area. This paper aims to provide a quantitative methodology for the assessment of economic losses associated with flood scenarios. The proposed methodology was performed for an urban area in Southern Italy prone to hydrogeological instabilities. At first, the main physical characteristics of the area such as rainfall, land use, permeability, roughness, and slopes of the area under investigation were estimated in order to obtain input for flooding simulations. Afterwards, the analysis focused on the spatial variability incidence of the rainfall parameters in flood events. The hydraulic modeling provided different flood hazard scenarios. The risk curve obtained by plotting economic consequences vs. the return period for each hazard scenario can be a useful tool for local authorities to identify adequate risk mitigation measures and therefore prioritize the economic resources necessary for the implementation of such mitigation measures. Full article
(This article belongs to the Special Issue Hydrological and Hydrogeological Risks)
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Open AccessArticle Magnetic Properties of Iron Sand from the Tor River Estuary, Sarmi, Papua
Geosciences 2018, 8(4), 113; https://doi.org/10.3390/geosciences8040113
Received: 25 February 2018 / Revised: 27 March 2018 / Accepted: 27 March 2018 / Published: 30 March 2018
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Abstract
Information about the strategic mineral balance, published in 2013, presumed a significant amount of iron sand deposited in Sarmi, Papua, Indonesia. However, the magnetic properties of these iron sands have never been studied. Our preliminary study on the distribution of magnetic susceptibility of
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Information about the strategic mineral balance, published in 2013, presumed a significant amount of iron sand deposited in Sarmi, Papua, Indonesia. However, the magnetic properties of these iron sands have never been studied. Our preliminary study on the distribution of magnetic susceptibility of iron sand from the Sarmi Coast area has revealed that the iron sand from the Tor River estuary had the highest mass-specific magnetic susceptibility values with an χLF average of 3.083 ×10−5 m3/kg. We extracted the raw sand from the Tor River estuary using a mechanical magnetic extraction method and analyzed the magnetic properties and mineral composition. The magnetic susceptibility values increased significantly with an χLF average of 27.496 ×10−5 m3/kg. The chemical composition acquired from both the X-ray fluorescence and energy dispersive spectroscopy confirmed that the magnetic properties of the extracted sample originated from the high percentage of iron oxide. The hysteresis curve showed high saturation magnetization about 24.7 (emu/g), remanent magnetization of about 6.1 (emu/g) and a low coercive field of about 20 (Oe). The X-ray diffraction patterns identified a magnesioferrite (MgFe2O4) mineral structure. This result showed the novelty of iron sand from Sarmi, Papua when compared with that from Java Island. Full article
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Open AccessArticle Impact of Climate Change on Flood Frequency and Intensity in the Kabul River Basin
Geosciences 2018, 8(4), 114; https://doi.org/10.3390/geosciences8040114
Received: 12 February 2018 / Revised: 15 March 2018 / Accepted: 15 March 2018 / Published: 30 March 2018
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Abstract
Devastating floods adversely affect human life and infrastructure. Various regions of the Hindukush-Karakoram-Himalayas receive intense monsoon rainfall, which, together with snow and glacier melt, produce intense floods. The Kabul river basin originates from the Hindukush Mountains and is frequently hit by such floods.
[...] Read more.
Devastating floods adversely affect human life and infrastructure. Various regions of the Hindukush-Karakoram-Himalayas receive intense monsoon rainfall, which, together with snow and glacier melt, produce intense floods. The Kabul river basin originates from the Hindukush Mountains and is frequently hit by such floods. We analyses flood frequency and intensity in Kabul basin for a contemporary period (1981–2015) and two future periods (i.e., 2031–2050 and 2081–2100) using the RCP4.5 and RCP8.5 scenarios based on four bias-corrected downscaled climate models (INM-CM4, IPSL-CM5A, EC-EARTH, and MIROC5). Future floods are modelled with the SWAT hydrological model. The model results suggest an increasing trend due to an increasing precipitation and higher temperatures (based on all climate models except INM-CM4), which accelerates snow and glacier-melt. All of the scenario results show that the current flow with a 1 in 50 year return period is likely to occur more frequently (i.e., 1 in every 9–10 years and 2–3 years, respectively) during the near and far future periods. Such increases in intensity and frequency are likely to adversely affect downstream population and infrastructures. This, therefore, urges for appropriate early precautionary mitigation measures. This study can assist water managers and policy makers in their preparation to adequately plan for and manage flood protection. Its findings are also relevant for other basins in the Hindukush-Karakoram-Himalayas region. Full article
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Open AccessArticle The Influence of Alteration of Aggregates on the Quality of the Concrete: A Case Study from Serpentinites and Andesites from Central Macedonia (North Greece)
Geosciences 2018, 8(4), 115; https://doi.org/10.3390/geosciences8040115
Received: 1 March 2018 / Revised: 28 March 2018 / Accepted: 28 March 2018 / Published: 31 March 2018
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Abstract
This study aims at the interpretation of the adverse effects of the secondary products in two types of rocks during their performance as concrete aggregates. Serpentinised peridotites contain serpentine, as the dominant secondary phase, which creates low microroughness on the particles and therefore
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This study aims at the interpretation of the adverse effects of the secondary products in two types of rocks during their performance as concrete aggregates. Serpentinised peridotites contain serpentine, as the dominant secondary phase, which creates low microroughness on the particles and therefore unfavorable surfaces for cement paste to adequately adhere to. Moreover, its soft and platy nature contributes to the development of platy defects along the contacts of the aggregate particles with the cement paste. Poor adherence of the paste, failures along the contacts of the aggregate particles and potential propagation of the defects into the concrete during curing (and perhaps subsequently in-service) explain the poor performance of highly serpentinised rocks as concrete aggregates. Andesites show a different composition with a variety of secondary products including albite, chlorite, calcite, Fe-oxides and clay minerals. The role of all these products was investigated and it appears that only smectite is important, as even small amounts of it may be detrimental to the quality of the rocks as concrete aggregates. It is likely that abnormal hydration reactions and considerable swelling of the smectite result in the appearance of defects in the concrete, hence contributing to its low performance. Full article
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Open AccessArticle Lithogenic and Anthropogenic Components in Surface Sediments from Lake Limboto as Shown by Magnetic Mineral Characteristics, Trace Metals, and REE Geochemistry
Geosciences 2018, 8(4), 116; https://doi.org/10.3390/geosciences8040116
Received: 24 February 2018 / Revised: 24 March 2018 / Accepted: 27 March 2018 / Published: 31 March 2018
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Abstract
Lake Limboto is one of the major lakes in Sulawesi, Indonesia. It is currently undergoing serious degradation due to population pressure. As more residential areas have been established around the lake, the sedimentation rate has increased because of the contribution of anthropogenic particles.
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Lake Limboto is one of the major lakes in Sulawesi, Indonesia. It is currently undergoing serious degradation due to population pressure. As more residential areas have been established around the lake, the sedimentation rate has increased because of the contribution of anthropogenic particles. In this study, the lithogenic and anthropogenic components in surface sediments from 17 points in the lake were studied and identified using a combination of magnetic and geochemical analyses. The results showed that although the magnetic susceptibility values in R (residential) and NR (non-residential) areas were relatively similar, the values of saturation isothermal remanent magnetization (SIRM) as well as those of SIRM/χLF differed significantly, implying that the magnetic characteristics of the lithogenic component (in the NR area) differ from those of the anthropogenic component (in the R area). The discrepancy between the anthropogenic and lithogenic contributions was further supported by trace metals and rare earth element (REE) contents. Sediment samples in the R area contained higher levels of Mn, La, Pr, and Gd, while in the NR area they contained higher levels of Fe, Sc, Nd, and Ce. The magnetic susceptibility also correlated strongly with Fe, Cu, Zn, and Mn contents in the NR area. A similar correlation was not observed in the R area. The results above imply that a combination of magnetic and geochemical analyses can successfully differentiate lithogenic and anthropogenic components or contributions in lake sediments. Full article
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Open AccessArticle Investigation of the Effect of Debris-Induced Damage for Constructing Tsunami Fragility Curves for Buildings
Geosciences 2018, 8(4), 117; https://doi.org/10.3390/geosciences8040117
Received: 30 September 2017 / Revised: 11 March 2018 / Accepted: 12 March 2018 / Published: 31 March 2018
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Abstract
Catastrophe models quantify potential losses from disasters, and are used in the insurance, disaster-risk management, and engineering industries. Tsunami fragility and vulnerability curves are key components of catastrophe models, providing probabilistic links between Tsunami Intensity Measures (TIMs), damage and loss. Building damage due
[...] Read more.
Catastrophe models quantify potential losses from disasters, and are used in the insurance, disaster-risk management, and engineering industries. Tsunami fragility and vulnerability curves are key components of catastrophe models, providing probabilistic links between Tsunami Intensity Measures (TIMs), damage and loss. Building damage due to tsunamis can occur due to fluid forces or debris impact; two effects which have different implications for building damage levels and failure mechanisms. However, existing fragility functions are generally derived using all available damage data for a location, regardless of whether damage was caused by fluid or debris effects. It is therefore not clear whether the inclusion of debris-induced damage introduces bias in existing functions. Furthermore, when modelling areas likely to be affected by debris (e.g., adjacent to ports), it is not possible to account for this increased likelihood of debris-induced damage using existing functions. This paper proposes a methodology to quantify the effect that debris-induced damage has on fragility and vulnerability function derivation, and subsequent loss estimates. A building-by-building damage dataset from the 2011 Great East Japan Earthquake and Tsunami is used, together with several statistical techniques advanced in the field of fragility analysis. First, buildings are identified which are most likely to have been affected by debris from nearby ‘washed away’ buildings. Fragility functions are then derived incorporating this debris indicator parameter. The debris parameter is shown to be significant for all but the lowest damage state (“minor damage”), and functions which incorporate the debris parameter are shown to have a statistically significant better fit to the observed damage data than models which omit debris information. Finally, for a case study scenario simulated economic loss is compared for estimates from vulnerability functions which do and do not incorporate a debris term. This comparison suggests that biases in loss estimation may be introduced if not explicitly modelling debris. The proposed methodology provides a step towards allowing catastrophe models to more reliably predict the expected damage and losses in areas with increased likelihood of debris, which is of relevance for the engineering, disaster risk-reduction and insurance sectors. Full article
(This article belongs to the Special Issue Interdisciplinary Geosciences Perspectives of Tsunami)
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Open AccessArticle Formation MicroScanner Providing Better Answers for Carbonate Secondary Porosity in Alamein Dolomite Formation, NW Desert, Egypt
Geosciences 2018, 8(4), 118; https://doi.org/10.3390/geosciences8040118
Received: 19 December 2017 / Revised: 6 March 2018 / Accepted: 13 March 2018 / Published: 2 April 2018
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Abstract
The use of borehole imaging tools has become widespread in recent years with more specialized studies of reservoir properties, particularly in highly-porous and fractured carbonate systems. In this study, the Formation MicroScanner (FMS) borehole imaging tool and conventional well log data have been
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The use of borehole imaging tools has become widespread in recent years with more specialized studies of reservoir properties, particularly in highly-porous and fractured carbonate systems. In this study, the Formation MicroScanner (FMS) borehole imaging tool and conventional well log data have been used to study the secondary porosity of the dolomitic Alamein Formation in the Alamein Field, north Western Desert, Egypt. Based on well log analyses of the formation from Tourmaline-1X and N.Alamein-6X wells, we show that secondary porosity occurs across the formation, and is filled mostly with hydrocarbon. We also show that the formation has good average effective porosity and hydrocarbon saturation. FMS images of the Tourmaline-1X well confirms that the formation is intermittently vuggy with solution-filled channels from the top to its base. The vug pores are observed to be well-connected, which supports good effective porosity values interpreted from petrophysical data. An additional set of core photographs of the Alamein Formation from N.Alamein-5X well confirms the presence of secondary pores, which are filled by hydrocarbon, and exhibit intense fluorescence under UV light. Our results show that the abundance of secondary porosity in Alamein Formation would play a key role in evaluating its reservoir quality and reservoir performance. Full article
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Open AccessArticle Multiscale and Hierarchical Classification for Benthic Habitat Mapping
Geosciences 2018, 8(4), 119; https://doi.org/10.3390/geosciences8040119
Received: 28 February 2018 / Revised: 29 March 2018 / Accepted: 30 March 2018 / Published: 2 April 2018
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Abstract
Developing quantitative and objective approaches to integrate multibeam echosounder (MBES) data with ground observations for predictive modelling is essential for ensuring repeatability and providing confidence measures for benthic habitat mapping. The scale of predictors within predictive models directly influences habitat distribution maps, therefore
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Developing quantitative and objective approaches to integrate multibeam echosounder (MBES) data with ground observations for predictive modelling is essential for ensuring repeatability and providing confidence measures for benthic habitat mapping. The scale of predictors within predictive models directly influences habitat distribution maps, therefore matching the scale of predictors to the scale of environmental drivers is key to improving model accuracy. This study uses a multi-scalar and hierarchical classification approach to improve the accuracy of benthic habitat maps. We used a 700-km2 region surrounding Cape Otway in Southeast Australia with full MBES data coverage to conduct this study. Additionally, over 180 linear kilometers of towed video data collected in this area were classified using a hierarchical classification approach. Using a machine learning approach, Random Forests, we combined MBES bathymetry, backscatter, towed video and wave exposure to model the distribution of biotic classes at three hierarchical levels. Confusion matrix results indicated that greater numbers of classes within the hierarchy led to lower model accuracy. Broader scale predictors were generally favored across all three hierarchical levels. This study demonstrates the benefits of testing predictor scales across multiple hierarchies for benthic habitat characterization. Full article
(This article belongs to the Special Issue Marine Geomorphometry)
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Open AccessArticle Geology and Isotope Systematics of the Jianchaling Au Deposit, Shaanxi Province, China: Implications for Mineral Genesis
Geosciences 2018, 8(4), 120; https://doi.org/10.3390/geosciences8040120
Received: 9 March 2018 / Revised: 26 March 2018 / Accepted: 29 March 2018 / Published: 3 April 2018
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Abstract
The giant Jianchaling Au (52 t Au) deposit is located in the Mian-Lue-Yang Terrane in the southern part of the Qinling Orogen of central China and is hosted by metamorphosed carbonate rocks of the Late Neoproterozoic Duantouya Formation. The deposit consists of multiple
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The giant Jianchaling Au (52 t Au) deposit is located in the Mian-Lue-Yang Terrane in the southern part of the Qinling Orogen of central China and is hosted by metamorphosed carbonate rocks of the Late Neoproterozoic Duantouya Formation. The deposit consists of multiple generations of mineralised quartz(-carbonate) veins in WNW-trending extensional ductile-brittle shear zones. Based on the mineral assemblages and cross-cutting relationships between the quartz(-carbonate) veins, the paragenesis is characterised by an early coarse-grained pyrite-pyrrhotite-pentlandite-dolomite-quartz assemblage (I), followed by pyrite-sphalerite-galena-carbonate-arsenopyrite-fuchsite-carbonate-quartz containing gold (II), and fine-grained pyrite-dolomite-calcite-quartz-realgar (As2S2)-orpiment (As2S3) (III). The H-O-C isotope systematics for the three vein sets indicate that the mineralising fluid is probably sourced from the metamorphic dehydration of carbonate rocks in the Duantouya Formation, and gradually mixed with meteoric water during the emplacement of the third vein set. The δ34S values for sulfides (6.3–16.6‰) from the second auriferous vein set are greater than zero, indicating sulfates reduction from the Neoproterozoic metamorphic rocks (Duantouya Fm). The (206Pb/204Pb)i ratios from pyrite (17.521–18.477) from each of the vein sets overlap those of the ultramafic rocks (18.324–18.717) and the Bikou Group (17.399–18.417), indicating that the units are possible sources for the sulfides in the mineralisation. Both εNd(t) and Isr(t) of sulfide overlap with the meta-ultramafic field and Duantouya formation and dominated with mature Sr-Nd character, which indicated that the Duantouya may play an important role during the ore formation and there may exist a minor ultramafic source that is involved in the ore fluid. The S-Pb-Sr-Nd isotopic ratios are closely related to those of the Bikou Group and Duantouya Formation, which indicates that the mineralised fluid has interacted with both units. Combining the previously published data with data from this study on the mineralised area, we surmise that Jianchaling is characteristic of an orogenic-type gold deposit related to the Triassic Qinling Orogeny associated with continental collision. Full article
(This article belongs to the Special Issue Magmatic-Hydrothermal Ore Deposits)
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Open AccessArticle Coastal Evolution, Hydrothermal Migration Pathways and Soft Deformation along the Campania Continental Shelf (Southern Tyrrhenian Sea): Insights from High-Resolution Seismic Profiles
Geosciences 2018, 8(4), 121; https://doi.org/10.3390/geosciences8040121
Received: 17 October 2017 / Revised: 21 March 2018 / Accepted: 21 March 2018 / Published: 4 April 2018
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Abstract
A closely spaced set of high-resolution Chirp-Sonar and Sparker profiles and swath bathymetric data was acquired in 2013 for the I-AMICA Project off the Volturno River mouth (Southern Tyrrhenian Sea) by the Istituto per l’Ambiente Marino Costiero (IAMC), National Research Council of Italy
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A closely spaced set of high-resolution Chirp-Sonar and Sparker profiles and swath bathymetric data was acquired in 2013 for the I-AMICA Project off the Volturno River mouth (Southern Tyrrhenian Sea) by the Istituto per l’Ambiente Marino Costiero (IAMC), National Research Council of Italy (CNR). The palaeo-topography of three key surfaces, represented by the bounding surfaces of the post-glacial lithosomes, was mapped by the interpolation of seismically detected reflectors. The morphology of the surface related to the Last Glacial Maximum (LGM) regression revealed the presence of fault linkages which defined a small-scale accommodation zone with an E–W trending interbasinal relative high. The observed set of oppositely dipping faults, NNW- and ENE-directed, locally controlled the deposition of the paralic/deltaic bodies during the post-glacial rise in sea level, as testified by their wedge-shaped geometries and shifting depocentres. The deformation may be linked to the Campi Flegrei caldera collapse following the Neapolitan Yellow Tuff (NYT) eruption and aged 15 ka BP. The relevant thickness of the Transgressive System Tract (TST) testifies to an increased sediment yield and intense reworking in coastal areas, probably driven by the high volcanoclastic supply during volcanic paroxysm, almost coeval with the post-glacial transgression. Fluid escape features linked to an E–W striking fluid front at the outer shelf suggest the presence of an hydrothermal system controlled by the predominant direction of normal to oblique Quaternary-active faults and by lithologic discontinuities across the sedimentary pile. Full article
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Open AccessArticle Comparison of SCS and Green-Ampt Distributed Models for Flood Modelling in a Small Cultivated Catchment in Senegal
Geosciences 2018, 8(4), 122; https://doi.org/10.3390/geosciences8040122
Received: 29 January 2018 / Revised: 27 March 2018 / Accepted: 29 March 2018 / Published: 4 April 2018
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Abstract
The vulnerability to floods in Africa has increased over the last decades, together with a modification of land cover as urbanized areas are increasing, agricultural practices are changing, and deforestation is increasing. Rainfall-runoff models that properly represent land use change and hydrologic response
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The vulnerability to floods in Africa has increased over the last decades, together with a modification of land cover as urbanized areas are increasing, agricultural practices are changing, and deforestation is increasing. Rainfall-runoff models that properly represent land use change and hydrologic response should be useful for the development of water management and mitigation plans. Although some studies have applied rainfall-runoff models in West Africa for flood modelling, there is still a need to develop such models, while many data are available and have not still been used for modelling improvement. The Ndiba catchment (16.2 km2), which is located in an agricultural area in south Senegal, is such catchment, where a lot of hydro-climatic data has been collected between 1983 and 1992. Twenty-eight flood events have been extracted and modelled by two event-based rainfall-runoff models that are based on the Soil Conservation Service (SCS) or the Green-Ampt (GA) models for runoff, both coupled with the distributed Lag and Route (LR) for routing. Both models were able to reproduce the flood events after calibration, but they had to account for that the infiltration processes are highly dependent on the tillage of the soils and the growing of the crops during the rainy season, which made the initialization of the event-based models difficult. The most influent parameters for both models (the maximal water storage capacity for SCS, the hydraulic conductivity at saturation for Green-Ampt) were mostly related to the development stage of the vegetation, described by a Normalized Difference Vegetation Index (NDVI) anomaly. The SCS model performed finally better than the Green-Ampt model, because Green-Ampt was very sensitive to the variability of the hydraulic conductivity at saturation. The variability of the parameters of the models highlights the complexity of this kind of cultivated catchment, with highly non stationary conditions. The models could be improved by a better knowledge of the tillage practices, and a better integration of these practices in the parameters predictors. Full article
(This article belongs to the Special Issue Hydrological Hazard: Analysis and Prevention)
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Open AccessArticle Membrane Separation of Ammonium Bisulfate from Ammonium Sulfate in Aqueous Solutions for CO2 Mineralisation
Geosciences 2018, 8(4), 123; https://doi.org/10.3390/geosciences8040123
Received: 24 February 2018 / Revised: 29 March 2018 / Accepted: 2 April 2018 / Published: 4 April 2018
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Abstract
The separation of ammonium bisulfate (ABS) from ammonium sulfate (AS) in aqueous solutions by monovalent ion selective membranes was studied. Optimised usage of these chemicals is both an important and challenging step towards a more efficient CO2 mineralisation process route developed at
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The separation of ammonium bisulfate (ABS) from ammonium sulfate (AS) in aqueous solutions by monovalent ion selective membranes was studied. Optimised usage of these chemicals is both an important and challenging step towards a more efficient CO2 mineralisation process route developed at Åbo Akademi University (ÅA). The membranes were placed in a three or five-compartment electrodialysis stack. Silver, stainless steel and platinum electrodes were tested, of which a combination of Pt (anode) and stainless steel (cathode) electrodes were found to be most suitable. Separation efficiencies close to 100% were reached based on ABS concentrations in the feed solution. The tests were performed with an initial voltage of either 10 V–20 V, but limitations in the electrical power supply equipment eventually resulted in a voltage drop as separation proceeded. Exergy calculations for energy efficiency assessment show that the input exergy (electrical power) is many times higher than the reversible mixing exergy, which indicates that design modifications must be made. Further work will focus on the possibilities to make the separation even more efficient and to develop the analysis methods, besides the use of another anode material. Full article
(This article belongs to the Special Issue Carbon Sequestration)
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Open AccessArticle The Influence of Pre-Existing Deformation and Alteration Textures on Rock Strength, Failure Modes and Shear Strength Parameters
Geosciences 2018, 8(4), 124; https://doi.org/10.3390/geosciences8040124
Received: 7 December 2017 / Revised: 21 March 2018 / Accepted: 27 March 2018 / Published: 5 April 2018
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Abstract
This study uses the uniaxial compressive strength (UCS), the indirect tensile strength (ITS) and the point load tests (PLT) to determine the strength and deformation behavior of previously deformed and altered tonalite and anorthosite. In general, veined samples show higher strength because the
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This study uses the uniaxial compressive strength (UCS), the indirect tensile strength (ITS) and the point load tests (PLT) to determine the strength and deformation behavior of previously deformed and altered tonalite and anorthosite. In general, veined samples show higher strength because the vein material has both cohesive and adhesive properties while fractures have no cohesion, only frictional resistance. This implies that each rock category has to be treated independently and absolute strength predictions are inaccurate. Thus, the conversion factor k is a sample specific parameter and does not have a universal value. The ratio of UCS/ITS appears to be related to the rock strength and can be used to classify rocks based on their strength. The shear strength parameters, the friction angle and the cohesion, cannot be calculated for rocks with pre-existing planes of weakness. Reactivation is favoured only for planes oriented less than 20° to the maximum stress. For planes oriented between 20° and 50° to the maximum stress, failure occurs by a combination of reactivation and newly formed fractures, while for orientations above 50°, new shear fractures are favoured. This suggest that the Byerlee’s law of reactivation operates exclusively for planes oriented ≤10° to the maximum stress. Full article
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Open AccessArticle Groundwater Vulnerability to Pollution Map for Karst Aquifer Protection (Ziria Karst System, Southern Greece)
Geosciences 2018, 8(4), 125; https://doi.org/10.3390/geosciences8040125
Received: 8 March 2018 / Revised: 29 March 2018 / Accepted: 3 April 2018 / Published: 5 April 2018
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Abstract
In recent years vulnerability maps have been used as a tool to highlight the areas with the greatest potential for groundwater pollution based on the hydrogeological conditions and their respective human impacts. Several regions of Greece depend completely or partially on drinking water
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In recent years vulnerability maps have been used as a tool to highlight the areas with the greatest potential for groundwater pollution based on the hydrogeological conditions and their respective human impacts. Several regions of Greece depend completely or partially on drinking water from karst aquifers; thus, the production of vulnerability maps for such karstic areas is considered essential. In the present study, an assessment of aquifer intrinsic vulnerability has been conducted applying the COP method in the Ziria karst system. The latter is located at the Northeast part of Peloponnese in South Greece and is used as a public resource for drinking water. This method, which has been developed for carbonate (karst) aquifers, uses the properties of the overlying layers above the water table (O factor), the concentration of flow (C factor) and the precipitation regime (P factor) over the aquifer. The COP method considers karstic landforms as factors that decrease the natural protection provided by the overlying layers of a karst aquifer. With the use of GIS tools, vulnerability maps were produced highlighting the different degrees of intrinsic vulnerability in the karst system of Ziria. Full article
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Open AccessArticle Probabilistic Estimates of Ground Motion in the Los Angeles Basin from Scenario Earthquakes on the San Andreas Fault
Geosciences 2018, 8(4), 126; https://doi.org/10.3390/geosciences8040126
Received: 28 December 2017 / Revised: 4 March 2018 / Accepted: 28 March 2018 / Published: 6 April 2018
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Abstract
Kinematic source inversions of past earthquakes in the magnitude range of 6–8 are used to simulate 60 scenario earthquakes on the San Andreas fault. The unilateral rupture scenario earthquakes are hypothetically located at 6 locations spread out uniformly along the southern section of
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Kinematic source inversions of past earthquakes in the magnitude range of 6–8 are used to simulate 60 scenario earthquakes on the San Andreas fault. The unilateral rupture scenario earthquakes are hypothetically located at 6 locations spread out uniformly along the southern section of the fault, each associated with two hypocenters and rupture directions. Probabilities of occurrence over the next 30 years are assigned to each of these earthquakes by mapping the probabilities of 10,445 plausible earthquakes postulated for this section of the fault by the Uniform California Earthquake Rupture Forecast. Three-component broadband ground motion histories are computed at 636 sites in the greater Los Angeles metropolitan area by superposing short-period (0.2–2.0 s) empirical Green’s function synthetics on top of long-period (>2.0 s) spectral element synthetics. The earthquake probabilities and the computed ground motions are combined to develop probabilistic estimates of ground shaking in the region from San Andreas fault earthquakes over the next 30 years. The results could be useful in city planning, emergency management, and building code enhancement. Full article
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Open AccessArticle Estimating Regional Scale Hydroclimatic Risk Conditions from the Soil Moisture Active-Passive (SMAP) Satellite
Geosciences 2018, 8(4), 127; https://doi.org/10.3390/geosciences8040127
Received: 5 February 2018 / Revised: 20 March 2018 / Accepted: 3 April 2018 / Published: 7 April 2018
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Abstract
Satellite soil moisture is a critical variable for identifying susceptibility to hydroclimatic risks such as drought, dryness, and excess moisture. Satellite soil moisture data from the Soil Moisture Active/Passive (SMAP) mission was used to evaluate the sensitivity to hydroclimatic risk events in Canada.
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Satellite soil moisture is a critical variable for identifying susceptibility to hydroclimatic risks such as drought, dryness, and excess moisture. Satellite soil moisture data from the Soil Moisture Active/Passive (SMAP) mission was used to evaluate the sensitivity to hydroclimatic risk events in Canada. The SMAP soil moisture data sets in general capture relative moisture trends with the best estimates from the passive-only derived soil moisture and little difference between the data at different spatial resolutions. In general, SMAP data sets overestimated the magnitude of moisture at the wet extremes of wetting events. A soil moisture difference from average (SMDA) was calculated from SMAP and historical Soil Moisture and Ocean Salinity (SMOS) data showed a relatively good delineation of hydroclimatic risk events, although caution must be taken due to the large variability in the data within risk categories. Satellite soil moisture data sets are more sensitive to short term water shortages than longer term water deficits. This was not improved by adding “memory” to satellite soil moisture indices to improve the sensitivity of the data to drought, and there is a large variability in satellite soil moisture values with the same drought severity rating. Full article
(This article belongs to the Special Issue Drought Monitoring and Prediction)
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Open AccessArticle Basin Resonance and Seismic Hazard in Jakarta, Indonesia
Geosciences 2018, 8(4), 128; https://doi.org/10.3390/geosciences8040128
Received: 2 January 2018 / Revised: 22 March 2018 / Accepted: 4 April 2018 / Published: 7 April 2018
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Abstract
We use earthquake ground motion modelling via Ground Motion Prediction Equations (GMPEs) and numerical simulation of seismic waves to consider the effects of site amplification and basin resonance in Jakarta, the capital city of Indonesia. While spectral accelerations at short periods are sensitive
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We use earthquake ground motion modelling via Ground Motion Prediction Equations (GMPEs) and numerical simulation of seismic waves to consider the effects of site amplification and basin resonance in Jakarta, the capital city of Indonesia. While spectral accelerations at short periods are sensitive to near-surface conditions (i.e., V S 30 , average shear-wave velocity at topmost 30 m of soil), our results suggest that, for basins as deep as Jakarta’s, available GMPEs cannot be relied on to accurately estimate the effect of basin depth on ground motions at long periods (>3 s). Amplitudes at such long periods are influenced by trapping of seismic waves in the basin, resulting in longer duration of strong ground motion, and interference between incoming and reflected waves as well as focusing at basin edges may amplify seismic waves. In order to simulate such phenomena in detail, a basin model derived from a previous study is used as a computational domain for deterministic earthquake scenario modeling in a 2-dimensional cross-section. A M w 9.0 megathrust, a M w 6.5 crustal thrust and a M w 7.0 intraslab earthquake are chosen as scenario events that pose credible threats to Jakarta, and the interactions with the basin of seismic waves generated by these events were simulated. The highest long-period PGVs amplifications are recorded at sites near the middle of the basin and near its southern edge, with maximum amplifications of PGV in the horizontal component of 726% for the crustal, 1500% for the megathrust and 1125% for the deep intraslab earthquake scenario, respectively. We find that the levels of response spectral acceleration fall below those of the 2012 Indonesian building Codes’s design response spectra for short periods (<1 s), but closely approach or may even exceed these levels for longer periods. Full article
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Open AccessArticle Preventing Groundwater Pollution Using Vulnerability and Risk Mapping: The Case of the Florina Basin, NW Greece
Geosciences 2018, 8(4), 129; https://doi.org/10.3390/geosciences8040129
Received: 20 March 2018 / Revised: 3 April 2018 / Accepted: 4 April 2018 / Published: 8 April 2018
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Abstract
The alluvial aquifer system of the Florina basin (320 km2) in North Greece is a representative area where irrigated agriculture is applied. Groundwater is the main source of water. The highest and mean nitrate concentrations in groundwater are 67.9 mg/L and
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The alluvial aquifer system of the Florina basin (320 km2) in North Greece is a representative area where irrigated agriculture is applied. Groundwater is the main source of water. The highest and mean nitrate concentrations in groundwater are 67.9 mg/L and 25 mg/L, respectively. High values could be associated with the use of nitrogen fertilizers from agricultural activities. This study deals with the evaluation of the groundwater quality. For this reason, hydrochemical analyses from 29 groundwater samples and water level measurements were performed for the wet and dry periods of 2016. The suitability of groundwater quality for irrigation purposes is examined by using different indices (Chlorinity Index, SAR, Sodium Percentage, Potential Salinity and Kelly’s index). In addition, the DRASTIC method was modified by using statistical methods, land use map and nitrate concentrations and applied in order to assess the groundwater vulnerability to external pollution. Notably, there was no correlation between the standard DRASTIC method and nitrate concentrations. However, the modified version and the obtained risk map showed high correlation with nitrate concentrations (ρ = 0.55) and the Groundwater Quality; hence, it is suggested as the base for a protection plan of the alluvial aquifer. Full article
(This article belongs to the Special Issue Groundwater Pollution)
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Open AccessArticle A Physical Study of the Effect of Groundwater Salinity on the Compressibility of the Semarang-DemakAquitard, Java Island
Geosciences 2018, 8(4), 130; https://doi.org/10.3390/geosciences8040130
Received: 26 January 2018 / Revised: 25 March 2018 / Accepted: 4 April 2018 / Published: 8 April 2018
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Abstract
Semarang-Demak and other cities along the coast of North Java are vulnerable to land subsidence. The presence of saline groundwater in the coastal region is thought to affect the high subsidence rate, in this case the compressibility of the aquitard layer. We aimed
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Semarang-Demak and other cities along the coast of North Java are vulnerable to land subsidence. The presence of saline groundwater in the coastal region is thought to affect the high subsidence rate, in this case the compressibility of the aquitard layer. We aimed to analyze the effects of groundwater salinity on the compression characteristics of the Semarang-Demak clay using physical analysis. Methods included the determination of groundwater salinity, clay mineralogy and fabrics, and consolidation tests under various salinity conditions. The Semarang-Demak clay is dominated by smectite of high activity, and saline clay exists at the depth of 10 to 35 m. Consolidation tests revealed that the increase insalinity increases the average consolidation rate and hydraulic conductivity up to 42% and 37.5%, respectively. Clay fabric analysis showed that the groundwater salinity modified the interconnectivity of pores by changing the fabric into parallel alignments, facilitating faster porewater dissipation, hence the clay is more readily compressed. These findings are useful for explaining the mechanism of the fast-subsiding coastal plains of North Java. Full article
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Open AccessArticle Determining Earthquake Susceptible Areas Southeast of Yogyakarta, Indonesia—Outcrop Analysis from Structure from Motion (SfM) and Geographic Information System (GIS)
Geosciences 2018, 8(4), 132; https://doi.org/10.3390/geosciences8040132
Received: 27 February 2018 / Revised: 27 March 2018 / Accepted: 2 April 2018 / Published: 12 April 2018
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Abstract
Located approximately a hundred kilometres north of Java Subduction Zone, Java Island has a complicated geology and geomorphology. The north zone is dominated by the folded area, the centre is dominated by the active volcanic arc and the south of Java including the
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Located approximately a hundred kilometres north of Java Subduction Zone, Java Island has a complicated geology and geomorphology. The north zone is dominated by the folded area, the centre is dominated by the active volcanic arc and the south of Java including the study area (Southeast part of Yogyakarta City), is dominated by the uplifted southern mountain. In general, the study area is part of the Bantul’s Graben. In the middle part of study area flows the Opak River, which is often associated with normal faults of Opak Fault. The Opak Fault is such a complex fault system which has a complex local fault which can cause worst local site effect when earthquakes occur. However, the geology map of Yogyakarta is the only data that gives the characteristics of Opak Fault roughly. Thus, the effort to identify unchartered fault system needs to be done. The aims of this study are to conduct the outcrop study, to identify the micro faults and to improve the understanding of faults system to support the earthquake hazard and risk assessment. The integrated method of remote sensing, structure from motion (SfM), geographic information system (GIS) and direct outcrop observation was conducted in the study area. Remote sensing was applied to recognize the outcrop location and to extract the nature lineament feature which can be used as fault indicator. The structure from motion was used to support characterising the outcrop in the field, to identify the fault evidence, and to measure the fault displacement on the outcrops. The direct outcrop observation is very useful to reveal the lithofacies characteristics and to reconstruct the lithostratigraphic correlation among the outcrops. Meanwhile, GIS was used to analyse all the data from remote sensing, SfM, and direct outcrop observation. The main findings of this study were as follows: the middle part of study area has the most complicated geologic structure. At least 56 faults evidence with the maximum displacement of 2.39 m was found on the study area. Administratively, the north part of Segoroyoso Village, the middle part of Wonolelo Village, and the middle part of Bawuran village are very unstable and vulnerable to the ground motion amplification due to their faults configuration. The further studies such as geo-electric survey, boreholes survey, and detail geological mapping still need to be conducted in the study area to get better understanding of Opak Fault. Additionally, the carbon testing of charcoal that found in the outcrop and identification of exact location of the ancient eruption source also need to be done. Full article
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Open AccessArticle Multi-Analytical Approach for Identifying Asbestos Minerals In Situ
Geosciences 2018, 8(4), 133; https://doi.org/10.3390/geosciences8040133
Received: 19 March 2018 / Revised: 7 April 2018 / Accepted: 12 April 2018 / Published: 15 April 2018
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Abstract
An innovative and, as yet, untested approach is to analyze serpentinite and metabasite rocks containing asbestos using a portable multi-analytical device, which combines portable digital microscopy (p-DM), portable X-ray Fluorescence (p-XRF) and portable micro-Raman Spectroscopy (p-µR). The analyses were carried out in two
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An innovative and, as yet, untested approach is to analyze serpentinite and metabasite rocks containing asbestos using a portable multi-analytical device, which combines portable digital microscopy (p-DM), portable X-ray Fluorescence (p-XRF) and portable micro-Raman Spectroscopy (p-µR). The analyses were carried out in two inactive quarries of serpentinitic and metabasitic rocks from the Gimigliano-Mount Reventino Unit (Southern Italy) already characterized in previous studies, with the aim of testing the efficiency of these portable tools. In this study, a portable X-ray fluorescence analyzer was used to obtain the in situ rapid chemical discrimination of serpentinite and metabasite rocks. The characterization of outcropping rocks using portable devices enabled us to detect the presence of chrysotile and asbestos tremolite. The results obtained were consistent with the findings from previous research studies and therefore combining p-DM, p-XRF and p-µR could be a useful approach for discriminating asbestos contained in outcropping rocks, especially when sampling is prohibited or for field-based sampling. Full article
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Open AccessArticle Effects of pH-Induced Changes in Soil Physical Characteristics on the Development of Soil Water Erosion
Geosciences 2018, 8(4), 134; https://doi.org/10.3390/geosciences8040134
Received: 30 January 2018 / Revised: 14 March 2018 / Accepted: 19 March 2018 / Published: 16 April 2018
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Soil water erosion is frequently reported as serious problem in soils in Southeast Asia with tropical climates, and the variations in pH affect the development of the erosion. This study investigated the effects of changes in pH on soil water erosion based on
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Soil water erosion is frequently reported as serious problem in soils in Southeast Asia with tropical climates, and the variations in pH affect the development of the erosion. This study investigated the effects of changes in pH on soil water erosion based on changes in the physical properties of the simulated soils with pH adjusted from 2.0 to 10.0 through artificial rainfall tests. The zeta potential was entirely shifted to positive direction at each pH condition due to Al, Ca, and Mg. In the pH range of 6.0 to 2.0, the aggregation of soil particles resulting from the release of Al3+ from clay minerals and/or molecular attraction between soil particles caused the plastic index (IP) of the soil to decrease. The decrease in IP led to the development of soil water erosion at the pH range. When the pH exceeded 6.0, the repulsive force generated by the negative charges on soil particles decreased IP, resulting in accelerated erosion by water. The results suggest that changes in pH causes physical properties of the soil to change through changes of the zeta potential in the clayey soil rich in Al, Ca, and Mg, leading to the development of soil water erosion. Full article
(This article belongs to the Special Issue Hydrology and Soil Erosion Modeling)
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Open AccessArticle Downscaling Africa’s Drought Forecasts through Integration of Indigenous and Scientific Drought Forecasts Using Fuzzy Cognitive Maps
Geosciences 2018, 8(4), 135; https://doi.org/10.3390/geosciences8040135
Received: 25 November 2017 / Revised: 25 March 2018 / Accepted: 9 April 2018 / Published: 16 April 2018
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Abstract
In the wake of increased drought occurrences being witnessed in Sub-Saharan Africa, more localized and contextualized drought mitigation strategies are on the agendas of many researchers and policy makers in the region. The integration of indigenous knowledge on droughts with seasonal climate forecasts
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In the wake of increased drought occurrences being witnessed in Sub-Saharan Africa, more localized and contextualized drought mitigation strategies are on the agendas of many researchers and policy makers in the region. The integration of indigenous knowledge on droughts with seasonal climate forecasts is one such strategy. The main challenge facing this integration, however, is the formal representation of highly-structured and holistic indigenous knowledge. In this paper, we demonstrate how the use of fuzzy cognitive mapping can address this challenge. Indigenous knowledge on droughts from five communities was modeled and represented using fuzzy cognitive maps. Maps from one of these case communities were then used in the implementation of the integration framework, called ĩtiki. Full article
(This article belongs to the Special Issue Drought Monitoring and Prediction)
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Open AccessArticle Modelling Ephemeral Gully Erosion from Unpaved Urban Roads: Equifinality and Implications for Scenario Analysis
Geosciences 2018, 8(4), 137; https://doi.org/10.3390/geosciences8040137
Received: 26 February 2018 / Revised: 7 April 2018 / Accepted: 7 April 2018 / Published: 17 April 2018
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Abstract
Modelling gully erosion in urban areas is challenging due to difficulties with equifinality and parameter identification, which complicates quantification 0of management impacts on runoff and sediment production. We calibrated a model (AnnAGNPS) of an ephemeral gully network that formed on unpaved roads following
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Modelling gully erosion in urban areas is challenging due to difficulties with equifinality and parameter identification, which complicates quantification 0of management impacts on runoff and sediment production. We calibrated a model (AnnAGNPS) of an ephemeral gully network that formed on unpaved roads following a storm event in an urban watershed (0.2 km2) in Tijuana, Mexico. Latin hypercube sampling was used to create 500 parameter ensembles. Modelled sediment load was most sensitive to the Soil Conservation Service (SCS) curve number, tillage depth (TD), and critical shear stress (τc). Twenty-one parameter ensembles gave acceptable error (behavioural models), though changes in parameters governing runoff generation (SCS curve number, Manning’s n) were compensated by changes in parameters describing soil properties (TD, τc), resulting in uncertainty in the optimal parameter values. The most suitable parameter combinations or “behavioural models” were used to evaluate uncertainty under management scenarios. Paving the roads increased runoff by 146–227%, increased peak discharge by 178–575%, and decreased sediment load by 90–94% depending on the ensemble. The method can be used in other watersheds to simulate runoff and gully erosion, to quantify the uncertainty of model-estimated impacts of management activities on runoff and erosion, and to suggest critical field measurements to reduce uncertainties in complex urban environments. Full article
(This article belongs to the Special Issue Hydrology and Soil Erosion Modeling)
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Open AccessArticle Best-Fit Probability Models for Maximum Monthly Rainfall in Bangladesh Using Gaussian Mixture Distributions
Geosciences 2018, 8(4), 138; https://doi.org/10.3390/geosciences8040138
Received: 26 February 2018 / Revised: 17 April 2018 / Accepted: 17 April 2018 / Published: 19 April 2018
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Abstract
In this study, Gaussian/normal distributions (N) and mixtures of two normal (N2), three normal (N3), four normal (N4), or five normal (N5) distributions were applied to data with extreme values for precipitation for 35 weather stations in Bangladesh. For parameter estimation, maximum likelihood
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In this study, Gaussian/normal distributions (N) and mixtures of two normal (N2), three normal (N3), four normal (N4), or five normal (N5) distributions were applied to data with extreme values for precipitation for 35 weather stations in Bangladesh. For parameter estimation, maximum likelihood estimation was applied by using an expectation-maximization algorithm. For selecting the best-fit model, graphical inspection (probability density function (pdf), cumulative density function (cdf), quantile-quantile (Q-Q) plot) and numerical criteria (Akaike’s information criterion (AIC), Bayesian information criterion (BIC), root mean square percentage error (RMSPE)) were used. In most of the cases, AIC and BIC gave the same best-fit results but their RMSPE results differed. The best-fit result of each station was chosen as the distribution with the lowest sum of the rank scores from each test statistic. The N distribution gave the best-fit result for 51% of the stations. N2 and N3 gave the best-fit for 20% and 14% of stations, respectively. N5 gave 11% of the best-fit results. This study also calculated the rainfall heights corresponding to 10-year, 25-year, 50-year, and 100-year return periods for each location by using the distributions to project more extreme values. Full article
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Open AccessArticle A Javascript GIS Platform Based on Invocable Geospatial Web Services
Geosciences 2018, 8(4), 139; https://doi.org/10.3390/geosciences8040139
Received: 28 January 2018 / Revised: 10 April 2018 / Accepted: 17 April 2018 / Published: 20 April 2018
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Abstract
Semantic Web technologies are being increasingly adopted by the geospatial community during last decade through the utilization of open standards for expressing and serving geospatial data. This was also dramatically assisted by the ever-increasing access and usage of geographic mapping and location-based services
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Semantic Web technologies are being increasingly adopted by the geospatial community during last decade through the utilization of open standards for expressing and serving geospatial data. This was also dramatically assisted by the ever-increasing access and usage of geographic mapping and location-based services via smart devices in people’s daily activities. In this paper, we explore the developmental framework of a pure JavaScript client-side GIS platform exclusively based on invocable geospatial Web services. We also extend JavaScript utilization on the server side by deploying a node server acting as a bridge between open source WPS libraries and popular geoprocessing engines. The vehicle for such an exploration is a cross platform Web browser capable of interpreting JavaScript commands to achieve interaction with geospatial providers. The tool is a generic Web interface providing capabilities of acquiring spatial datasets, composing layouts and applying geospatial processes. In an ideal form the end-user will have to identify those services, which satisfy a geo-related need and put them in the appropriate row. The final output may act as a potential collector of freely available geospatial web services. Its server-side components may exploit geospatial processing suppliers composing that way a light-weight fully transparent open Web GIS platform. Full article
(This article belongs to the Special Issue Geodata Management)
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Open AccessArticle Proximal Monitoring of the 2011–2015 Etna Lava Fountains Using MSG-SEVIRI Data
Geosciences 2018, 8(4), 140; https://doi.org/10.3390/geosciences8040140
Received: 21 December 2017 / Revised: 7 April 2018 / Accepted: 17 April 2018 / Published: 21 April 2018
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Abstract
From 2011 to 2015, 49 lava fountains occurred at Etna volcano. In this work, the measurements carried out from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) instrument, on board the Meteosat Second Generation (MSG) geostationary satellite, are processed to realize a proximal
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From 2011 to 2015, 49 lava fountains occurred at Etna volcano. In this work, the measurements carried out from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) instrument, on board the Meteosat Second Generation (MSG) geostationary satellite, are processed to realize a proximal monitoring of the eruptive activity for each event. The SEVIRI measurements are managed to provide the time series of start and duration of eruption and fountains, Time Averaged Discharge Rate (TADR) and Volcanic Plume Top Height (VPTH). Due to its temperature responsivity, the eruptions start and duration, fountains start and duration and TADR are realized by exploiting the SEVIRI 3.9 μm channel, while the VPTH is carried out by applying a simplified procedure based on the SEVIRI 10.8 μm brightness temperature computation. For each event, the start, duration and TADR have been compared with ground-based observations. The VPTH time series is compared with the results obtained from a procedures-based on the volcanic cloud center of mass tracking in combination with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) back-trajectories. The results indicate that SEVIRI is generally able to detect the start of the lava emission few hours before the ground measurements. A good agreement is found for both the start and the duration of the fountains and the VPTH with mean differences of about 1 h, 50 min and 1 km respectively. Full article
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Open AccessArticle The Monetary Measurement of Flood Damage and the Valuation of the Proactive Policies in Sicily
Geosciences 2018, 8(4), 141; https://doi.org/10.3390/geosciences8040141
Received: 16 March 2018 / Revised: 19 April 2018 / Accepted: 19 April 2018 / Published: 22 April 2018
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Abstract
Although floods, as well as other natural disasters, can be considered as relevant causes of intra-generational inequalities, frequent catastrophes and the resulting damage to the territory can be seen as a consequence of a generalized indifference about future. Land protection is one of
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Although floods, as well as other natural disasters, can be considered as relevant causes of intra-generational inequalities, frequent catastrophes and the resulting damage to the territory can be seen as a consequence of a generalized indifference about future. Land protection is one of the societal issues typically concerning inter-generational solidarity, involving the administrative system in the implementation of proactive policies. In the last three decades, the widespread demand for subsidiarity has made local communities more and more independent, so that attention to the long-term effects—typically concerning the territorial system as a whole at geographical scale—has been dispersed, and the proactive policies that come from the central government have become more ineffective. Regarding the case of the 2009 flood in the Fiumedinisi-Capo Peloro river basin in North Eastern Sicily, we propose an economic valuation of the land protection policy. This valuation, compared to the cost of recovery of the damaged areas, can provide helpful information on the decision-making process concerning the trade-off between reactive and proactive land policy. The economic value of land protection was calculated by means of the method of the imputed preferences, to obtain a real measure of the social territorial value from the point of view of the harmony between social system and environment. This method consists of an estimate based on the attribution of the expenditures according to the importance of the different areas. Since the value of land protection has been calculated by discounting the expenditures stream, some considerations about the economic significance of the proactive policy are referred to the role played by the social discount rate in the inter-temporal economic calculation. Full article
(This article belongs to the Special Issue Integrated Risk Analysis and Management of Floods)
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Open AccessArticle Site Effect Assessment of the Gros-Morne Hill Area in Port-au-Prince, Haiti, Part A: Geophysical-Seismological Survey Results
Geosciences 2018, 8(4), 142; https://doi.org/10.3390/geosciences8040142
Received: 22 January 2018 / Revised: 7 April 2018 / Accepted: 19 April 2018 / Published: 23 April 2018
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Abstract
After the M = 7.0 Haiti earthquake in 2010, many teams completed seismic risk studies in Port-au-Prince to better understand why this not extraordinarily strong event had induced one of the most severe earthquake disasters in history (at least in the Western World).
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After the M = 7.0 Haiti earthquake in 2010, many teams completed seismic risk studies in Port-au-Prince to better understand why this not extraordinarily strong event had induced one of the most severe earthquake disasters in history (at least in the Western World). Most highlighted the low construction quality as the main cause for the disaster, but some also pointed to possible soil and topographic amplification effects, especially in the lower and central parts of Port-au-Prince (e.g., close to the harbor). However, very detailed local studies of such site effects have not been completed yet. A Belgian-Haitian collaboration project was established in order to develop a detailed local seismic hazard study for Gros-Morne hill located in the district of Pétion-Ville, southeast of Port-au-Prince. In order to have a better understanding of the amplification on the Gros-Morne hill, in the southeastern part of Port-au-Prince, site effects were investigated by using near surface geophysical methods. The horizontal to vertical spectral ratio technique was applied to ambient vibrations and earthquake data, and multichannel analysis of surface waves and P-wave refraction tomography calculation were applied to seismic data. Standard spectral ratios were computed for the S-wave windows of the earthquake data recorded by a small temporary seismic network. Electrical resistivity tomography profiles were also performed in order to image the structure of the subsurface and detect the presence of water, if any. The spectral ratio results generally show low to medium (1.5–6) resonance amplitudes at one or several different resonance frequencies (for the same site), between 0.5 and 25 Hz. At most of the investigated sites, the fundamental resonance frequency varies between 7 and 10 Hz. By using the multichannel surface wave analyses of the seismic data, we were able to determine shear wave velocities ranging between 200 and 850 m/s, up to a depth of about 15–20 m. From the refraction analysis, we were able to delineate P-waves velocities of 500 to 1500–2000 m/s at the studied sites. The outputs were locally compared with the resistivity data from the electrical profiles. Thus, the overall data indicate a moderate site effect at Gros-Morne hill, with a great variability in site amplification distribution. Initial estimates of local site effects were made on the basis of those outputs and the earthquake recordings. Our results are finally discussed with respect to outputs and interpretations that had been published earlier for the same site. Those results only partly confirm the strong seismic amplification effects highlighted by previous papers for this hill site, which had been explained by the effects of the local topographic and soil characteristics. Full article
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Open AccessArticle Topographic Effects in Geoid Determinations
Geosciences 2018, 8(4), 143; https://doi.org/10.3390/geosciences8040143
Received: 1 April 2018 / Revised: 15 April 2018 / Accepted: 17 April 2018 / Published: 23 April 2018
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Abstract
Traditionally, geoid determination is applied by Stokes’ formula with gravity anomalies after removal of the attraction of the topography by a simple or refined Bouguer correction, and restoration of topography by the primary indirect topographic effect (PITE) after integration. This technique leads to
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Traditionally, geoid determination is applied by Stokes’ formula with gravity anomalies after removal of the attraction of the topography by a simple or refined Bouguer correction, and restoration of topography by the primary indirect topographic effect (PITE) after integration. This technique leads to an error of the order of the quasigeoid-to-geoid separation, which is mainly due to an incomplete downward continuation of gravity from the surface to the geoid. Alternatively, one may start from the modern surface gravity anomaly and apply the direct topographic effect on the anomaly, yielding the no-topography gravity anomaly. After downward continuation of this anomaly to sea-level and Stokes integration, a theoretically correct geoid height is obtained after the restoration of the topography by the PITE. The difference between the Bouguer and no-topography gravity anomalies (on the geoid or in space) is the “secondary indirect topographic effect”, which is a necessary correction in removing all topographic signals. In modern applications of an Earth gravitational model (EGM) in geoid determination a topographic correction is also needed in continental regions. Without the correction the error can range to a few metres in the highest mountains. The remove-compute-restore and Royal Institute of Technology (KTH) techniques for geoid determinations usually employ a combination of Stokes’ formula and an EGM. Both techniques require direct and indirect topographic corrections, but in the latter method these corrections are merged as a combined topographic effect on the geoid height. Finally, we consider that any uncertainty in the topographic density distribution leads to the same error in gravimetric and geometric geoid estimates, deteriorating GNSS-levelling as a tool for validating the topographic mass distribution correction in a gravimetric geoid model. Full article
(This article belongs to the Special Issue Gravity Field Determination and Its Temporal Variation)
Open AccessArticle Dynamics of Carbonates in Soils under Different Land Use in Forest-Steppe Area of Russia Using Stable and Radiogenic Carbon Isotope Data
Geosciences 2018, 8(4), 144; https://doi.org/10.3390/geosciences8040144
Received: 5 April 2018 / Revised: 20 April 2018 / Accepted: 21 April 2018 / Published: 23 April 2018
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Abstract
The work is aimed at the analysis of carbonate dynamics in soils under different land use. The studied area is located in the forest steppe - of the Central Russian Upland. Soils were sampled at four sites: a broadleaf forest, an adjacent 50-year
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The work is aimed at the analysis of carbonate dynamics in soils under different land use. The studied area is located in the forest steppe - of the Central Russian Upland. Soils were sampled at four sites: a broadleaf forest, an adjacent 50-year continuously cropped field including plots under a corn monoculture, bare fallow, and a crop rotation area with a clean fallow every fourth year. The carbonates’ morphology, their chemical composition, as well as their stable and radiogenic isotopes of carbon were studied. Clear-cut distinctions were found in the carbonate distribution throughout the profiles in the microstructure of carbonate pedofeatures, carbon isotopic composition, and radiocarbon age of carbonates between the pairs of the plots as follows: the bare fallow and the crop rotation on the one hand, and the corn monoculture and forest on the other. The distinctions are commonly assumed to result from repeating upward water fluxes, which are different in the bare soils and those with plant cover. A clear difference occurred in the hydrothermal regime for soils with and without plant cover, and was found to be the key factor of the observed differences. In addition, in soils under plant cover, the carbonate migration upward occurs due to process of transpiration, whereas in soils devoid of plants, it occurs due to physical evaporation. Full article
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Open AccessArticle Spectral Signature Characterization and Remote Mapping of Oman Exotic Limestones for Industrial Rock Resource Assessment
Geosciences 2018, 8(4), 145; https://doi.org/10.3390/geosciences8040145
Received: 11 December 2017 / Revised: 19 April 2018 / Accepted: 19 April 2018 / Published: 23 April 2018
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Abstract
This study demonstrates the capability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor data to remotely map industrial carbonate rocks known as the ‘Oman exotics’ of the Sultanate of Oman. We measured reflectance spectra of marble using a PIMA™ spectrometer and
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This study demonstrates the capability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor data to remotely map industrial carbonate rocks known as the ‘Oman exotics’ of the Sultanate of Oman. We measured reflectance spectra of marble using a PIMA™ spectrometer and studied their spectral absorptions distinguishing calcite from spectral absorptions of dolomite of the same region. The spectral band 8 of ASTER is processed by simple decorrelation stretch image processing method to map the exotic limestone rock of the Nakhl region, Oman. Results showed that carbonate rocks displayed distinctive tonal variation on the image. A comparative study with the spectral band 7 of Landsat 7 (ETM+) does not discriminate the calcite-bearing marbles and associated carbonate formations in the studied area. ASTER data were also processed by the application of the Maximum Likelihood Classification (MLC), Spectral Angle Mapper (SAM) and Spectral Information Divergence (SID) image classification algorithms. The results were assessed by the production of a confusion matrix. The study shows the capability of visible near infrared (VNIR) and shortwave infrared (SWIR) spectral bands of the ASTER sensor and potential of the image processing methods to remotely identify industrial carbonate rocks and we recommend this technique to similar regions of the world. Full article
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Open AccessReview Geoheritage, Geotourism and the Cultural Landscape: Enhancing the Visitor Experience and Promoting Geoconservation
Geosciences 2018, 8(4), 136; https://doi.org/10.3390/geosciences8040136
Received: 5 March 2018 / Revised: 27 March 2018 / Accepted: 3 April 2018 / Published: 16 April 2018
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Abstract
Geotourism spans a range of visitor interests, from the specialist geotourist to the more general visitor. As well as supporting geoconservation outcomes, it provides economic, cultural, relational and social benefits for both visitors and host communities. The interconnections between geoheritage and the cultural
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Geotourism spans a range of visitor interests, from the specialist geotourist to the more general visitor. As well as supporting geoconservation outcomes, it provides economic, cultural, relational and social benefits for both visitors and host communities. The interconnections between geoheritage and the cultural components of the landscape have antecedents in concepts of landscape aesthetics in different cultures. These interconnections provide a range of opportunities for enhancing the geotourist experience and promoting geoconservation and geoeducation by means of activities that involve aesthetic and emotional experiences and interpretation through different cultural filters that encourage the rediscovery of a sense of wonder both about the geological stories in the landscape and the human interactions. A cultural ecosystem services framework provides a holistic approach for informing conservation policy, management and planning for geotourism, enabling assessment of multiple benefits and trade-offs for visitors and communities based on the values of the geoheritage assets. Geotourism studies could also benefit from integration of existing theory, conceptual analysis and practice from broader heritage and nature-based tourism and closer collaboration with relevant social sciences. Adhering to sound geoethical practice is an essential part of geotourism, which can also play a role in the promotion of geoethics among the public and professionals. Full article
(This article belongs to the Special Issue Geotourism)
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Open AccessShort Note Twinning Strains in Synfolding Calcite, Proterozoic Sinian System, China
Geosciences 2018, 8(4), 131; https://doi.org/10.3390/geosciences8040131
Received: 1 March 2018 / Revised: 2 April 2018 / Accepted: 6 April 2018 / Published: 11 April 2018
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Abstract
Synfolding calcite was precipitated between layers of Neoproterozoic sandy dolomite and striated parallel to the fold axis of an open anticline with a shallow plunge during folding. The fold had limb dips of 45° and plunged 20° to the south. The synfolding calcite
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Synfolding calcite was precipitated between layers of Neoproterozoic sandy dolomite and striated parallel to the fold axis of an open anticline with a shallow plunge during folding. The fold had limb dips of 45° and plunged 20° to the south. The synfolding calcite had sub-horizontal grooves that trended parallel to the fold. Limb-hinge-limb calcite samples (3 samples; n = 100 grains) preserved a layer-parallel shortening strain that trended at an acute (45°) angle to the trend of the fold axis and fold lineations. Extension axes were vertical and there was no strain overprint (low NEVs). Shortening strain magnitudes were −2.9% and the differential stress responsible for twinning was −38 MPa. The commonly observed structures were layer-parallel slip striations normal to the fold axis: sub-horizontal interlayer slip surfaces parallel to a fold axis (parallel to bedding strike) were unreported; as was a sub-horizontal shortening strain at an acute angle to the axis of a plunging fold. Full article
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