Ghaleh-khargushi rhyodacite and Gorid andesite from Iran: characterization,uses, and durability     

Ahmad Zalooli  David Martín Freire-Lista  Mashalah Khamehchiyan  Mohammad Reza Nikudel  Rafael Fort  Shahram Ghasemi 《Environmental Earth Sciences》2018,77(8):315

Durability of building stones is an important issue in sustainable development. Crystallization of soluble salts is recognized as one of the most destructive weathering agents of building stones. For this reason, durability of Ghaleh-khargushi rhyodacite and Gorid andesite from Iran was investigated against sodium sulfate crystallization aging test. Petrographic and physico-mechanical properties and pore size distribution of these stones were examined before and after the aging test. The characteristics of the microcracks were quantified with fluorescence-impregnated thin sections. Durability and physico-mechanical characteristics of Ghaleh-khargushi rhyodacite are mainly influenced by preferentially oriented preexisting microcracks. Stress induced by salt crystallization led to the widening of preexisting microcracks in Ghaleh-khargushi rhyodacite, as confirmed by the pore size distributions before and after the aging test. The preexisting microcracks of Gorid andesite were attributed to the mechanical stress induced by contraction of lava during cooling. The number of transcrystalline microcracks was significantly increased after the aging test. The degree of plagioclase microcracking was proportional to its size. Durability of the studied stones depends on initial physico-mechanical properties, pore size distribution, and orientation of microcracks. Initial effective porosity is found to be a good indicator of the stones’ durability. Salt crystallization resulted in an increase in the effective porosity with a parallel decrease in the wave velocities. Surface microroughness parameters increased with the development of salt crystallization-induced microcracking. Gorid andesite showed higher quality and durability than Ghaleh-khargushi rhyodacite.  相似文献   

Assessing shallow landslide hazards using the TRIGRS and SHALSTAB models,Serra do Mar,Brazil     

Bianca Carvalho Vieira  Nelson Ferreira Fernandes  Oswaldo Augusto Filho  Tiago Damas Martins  David R. Montgomery 《Environmental Earth Sciences》2018,77(6):260

The hillslopes of the Serra do Mar, a system of escarpments and mountains that extend more than 1500 km along the southern and southeastern Brazilian coast, are regularly affected by heavy rainfall that generates widespread mass movements, causing large numbers of casualties and economic losses. This paper evaluates the efficiency of susceptibility mapping for shallow translational landslides in one basin in the Serra do Mar, using the physically based landslide susceptibility models SHALSTAB and TRIGRS. Two groups of scenarios were simulated using different geotechnical and hydrological soil parameters, and for each group of scenarios (A and B), three subgroups were created using soil thickness values of 1, 2, and 3 m. Simulation results were compared to the locations of 356 landslide scars from the 1985 event. The susceptibility maps for scenarios A1, A2, and A3 were similar between the models regarding the spatial distribution of susceptibility classes. Changes in soil cohesion and specific weight parameters caused changes in the area of predicted instability in the B scenarios. Both models were effective in predicting areas susceptible to shallow landslides through comparison of areas predicted to be unstable and locations of mapped landslides. Such models can be used to reduce costs or to define potentially unstable areas in regions like the Serra do Mar where field data are costly and difficult to obtain.  相似文献   

Evaluation of the effect of river style framework on water quality: application of geomorphological factors     

Hadi Nayyeri  Sahar Zandi 《Environmental Earth Sciences》2018,77(9):343

The Tarwal River basin with an area of 6560.20 km² is located in the eastern part of Iranian Kurdistan Province. This river crosses the Qorveh and Dehgolan plains and joins the Ghezel Ozan River in Zanjan Province. The importance of this river as a source for drinking water and agricultural and industrial uses in the region necessitates the need for research in this field. The main purpose of this study is to identify the natural features of the riverbed from the perspective of river geomorphology and to investigate their impact on water quality and river self-purification capacity. To achieve this, the river style framework was employed. To investigate the effects of each style framework on the river, a total of 20 samples from the entrance and outlet of styles were obtained using Impact Assessment method and sampling standards which were later analyzed for their quality parameters including T, pH, EC, TDS, TSS, Na, Ca, Mg, K, Cl, F, NO₂, NO₃, SO₄, PO₄, DO, COD and BOD. The results indicated that the changes in the styles lead to changes in water quality and the impact of each style is greater on the physical parameters than the chemical parameters. The river self-purification capacity varied depending on the style. The maximum and the minimum self-purifications occurred in fine-grained Anabranching and low-sinuosity fine-grained styles, respectively.  相似文献   

Statistical and geochemical assessment of groundwater quality in Teboursouk area (Northwestern Tunisian Atlas)     

Yosra Ayadi  Naziha Mokadem  Houda Besser  Belgacem Redhaounia  Faten Khelifi  Samia Harabi  Talel Nasri  Younes Hamed 《Environmental Earth Sciences》2018,77(9):349

Teboursouk region, Northwestern Tunisia, is characterized by the diversity of its natural resources (petroleum, groundwater and minerals). It constitutes a particular site widely studied, especially from a tectonic stand point as it exhibits a complex architecture dominated by multi-scale synclinals and Triassic extrusions. It has typical karst landform that constitutes important water resources devoted for human consumption and agriculture activities, besides to the exploitation of the Mio-Plio-Quaternary aquifer (MPQ). Thus, hydrogeological investigations play a significant role in the assessment of groundwater mineralization and the evaluation of the used water quality for different purposes. Hence, the current study based on a combined geochemical–statistical investigation of 50 groundwater samples from the multilayered aquifer system in the study area give crucial information about the principal factors and processes influencing groundwater chemistry. The chemical analysis of the water samples showed that Teboursouk groundwater is dominantly of Ca–Mg–Cl–SO₄ water type with little contribution of Ca–Mg–HCO₃, Na–K–Cl–SO₄ and Na–K–HCO₃. The total dissolved solids (TDS) values range from 0.37 to 3.58 g/l. The highest values are located near the Triassic outcrops. Furthermore, the hydrogeochemistry of the studied system was linked with various processes such as carbonates weathering, evaporites dissolution of Triassic outcrops and anthropogenic activities (nitrate contamination). Additionally, the main processes controlling Teboursouk water system were examined by means of multivariate statistical analysis (PCA and HCA) applied in this study based on 10 physicochemical parameters (TDS, pH, SO₄, HCO₃, pCO₂, Ca, Mg, Na, K, Cl and NO₃). Two principal components were extracted from PCA accounting 61% of total variance and revealing that the chemical characteristics of groundwater in the region were acquired through carbonates and evaporite dissolution besides to nitrate contamination. Similarly, according to Cluster analysis using Ward’s method and squared Euclidean distance, groundwater from the studied basin belongs to five different groups suggesting that the geochemical evolution of Teboursouk groundwater is controlled by dissolution of carbonates minerals, chemical weathering of Triassic evaporite outcrops, cation exchange and anthropogenic activities (nitrate contamination).  相似文献   

Effects of tilling methods on soil penetration resistance,organic carbon and water stable aggregates in a vineyard of semiarid Mediterranean environment   总被引：3，自引：0，他引：3  

Pietro Catania  Luigi Badalucco  Vito Armando Laudicina  Mariangela Vallone 《Environmental Earth Sciences》2018,77(9):348

Tillage, especially in semiarid Mediterranean environment, enhances the mineralization process of soil organic matter (SOM) and, in turn, decreases aggregate stability. Furthermore, continuous tillage leads to the formation of plough pan beneath the tilled layer. In the present study, we investigated the effect of an innovative self-propelled machine (spading machine, SM) for shallow tillage on SOM, water stable aggregates (WSA) and soil penetration resistance (PR). Such effects were compared to those of chisel plough (CP), rotary tiller (RT) and no tillage (NT). Each tilling method was applied up to a depth of 15 cm, whereas in NT only a brush cutter was used for weed control. Soil analyses were performed at the start of the experiment (March 2009, T0), in April 2010 (T1), May 2012 (T3), and June 2014 (T5) at both 0–15 and 15–30 cm. Compared to T0, soil PR increased with time in all the treatments and generally followed the order SM?<?RT?<?CP?<?NT. In soil tilled with the SM, soil PR never exceeded 2.5 MPa that was demonstrated to be a critical value for root elongation, and no evidence of the formation of plough pan beneath the tilled layer was observed. SOC as well as water content and WSA were higher in SM compared with CP and RT. In conclusion, the spading machine was proved to be more efficient in lowering the soil PR and in avoiding the formation of the plough pan. Furthermore, SM increased SOC and WSA.  相似文献   

Assessment of the acid drainage neutralization capacity and the toxic metals lixiviation of tailing from Guanajuato mining district,Mexico   总被引：1，自引：0，他引：1  

María Elena García-Arreola  Luisa María Flores-Vélez  Marcos Loredo-Tovías  Alfredo Aguillón-Robles  Rubén Alfonso López-Doncel  Irene Cano-Rodríguez  Sonia Hortensia Soriano-Pérez 《Environmental Earth Sciences》2018,77(9):355

In Mexico, many environmental problems are generated by large mining activities taking place in several mining districts. These mining activities produce great quantities of residues; large majorities of these have high sulfur content, which could generate acid drainage due to their interaction with the oxygen in the environment. The study area was located in the Mining District of Guanajuato, Mexico with abandoned tailings generated mainly by the gold and silver production. Two areas, called as Monte de San Nicolás (SN) and Peregrina (P) were selected for this study. The results study shows that there was no risk of production of acid drainage, since these tailings contained high amount of carbonates, which neutralized the generation of acidity and consequently decreased the possibility of leaching of some elements. However, not all elements leach in acid pH, as arsenic bound to oxyhydroxides, which is in a basic environment and its increased release by increasing the pH.  相似文献   

Geomagnetic field residuals from CHAMP satellite: <Emphasis Type="Italic">essential for revealing unmodelled sources</Emphasis>     

Sabrina Tair  Yasmina Yahiat  Mohamed Hamoudi  Vincent Lesur  Mioara Mandea  Ioan Rus 《Arabian Journal of Geosciences》2018,11(1):1

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Mapping groundwater recharge potential using GIS approach in Darwha block     

Nitin Patil  Vishnu Prakash Reddy  Anurag Patangray  Surendra Kumar Singh 《Arabian Journal of Geosciences》2018,11(1):8

Groundwater is the most important source of water in meeting irrigation, drinking, and other needs in India. The assessment of the potential zone for its recharge is critical for sustainable usage, quality management, and food security. This study reports alternative mapping of the groundwater recharge potential of a selected block by including large-scale soil data. Thematic layers of soil, geomorphology, slope, land use land cover, topographical wetness index, and drainage density of Darwha block (District Yavatmal, Maharashtra, India) were generated and integrated in a geographic information system environment. The topographic maps, thematic maps, field data, and satellite image were processed, classified, and weighted using analytical hierarchical process for their contribution to groundwater recharge. The layers were integrated by weighted linear combination method in the GIS environment to generate four groundwater potential zones viz., “poor,” “poor to moderate,” “moderate to high,” and “high.” Based on the generated groundwater potential map, about 9830 ha (12%) of the study area was categorized as high potential for recharge, 25,558 ha (31%) as poor to moderate, 33,398 ha (40%) as moderate to high, and 12,565 ha (15%) as poor potential zone. The zonation corresponds well with the field data on greater well density (0.22/ha) and irrigated crop area (27%) in the high potential zone as against 0.02 wells/ha and only 6% irrigated area in the poor zone. The map is recommended for use in regulating groundwater development decisions and judicious expenditure on drilling new wells by farmers and the state authorities.  相似文献   

Bi-cylindrical conformal map projection     

Hasan M. Bilani 《Arabian Journal of Geosciences》2018,11(1):7

Novel map projections can be derived by solving one of the two primary problems in mathematical cartography: direct and inverse. The combination of the equations of existing projections is a method that belongs to the direct problem category in mathematical cartography. As projections of different types, different classes, and different aspects can be combined, a considerable number of projections can be obtained by using this method. This paper aims to develop a novel projection by combining two conformal cylindrical projections with different aspects, namely normal and transverse, to reduce the distortions in map projection. It is observed that the resulting projection exhibits less distortion than those in normal and transverse cylindrical projections. Furthermore, the developed projection preserves conformality.  相似文献   

Accuracy assessment of noise mapping on the main street     

Bülent Bostanci 《Arabian Journal of Geosciences》2018,11(1):4

Among the sounds constituting a part of our daily lives, the undesired and disturbing ones are named noise. The noises can be defined as the acoustic energy that affects the physiological and psychological welfare of humans due to its direct or indirect effects on the human health. But, the traffic noise, which is one of the disturbing noises having wide dispersion in urban areas, affects the health of a gradually increasing number of people. The number of studies on measurement, dispersion, and mapping of traffic noise in developed and developing countries is gradually increasing. It can be seen that the studies concentrate on mapping based on the city centers and neighborhoods, where the traffic is intense. In this article, unlike the regional noise measurement studies, the transversal cross sections were established with a certain interval according to the land status along the main street, and the noise measurement points were determined using the global navigation satellite system (GNSS). The daily mean noise levels (L_den) were calculated by performing the measurements at daytime, evening, and nighttime. Using ArcGIS 10.4 software, the accuracy of noise maps created via inverse distance weighting (IDW), radial basis function (RBF), and ordinary kriging (OK) geostatistical analysis interpolation methods and the dispersion effect of traffic noise were compared. According to the visual method and error corrections, it was found that the best noise map was obtained using the RBF method. It is believed that the map provides accurate and reliable results because of the flat land surface, higher noise values measured on the road region, decrease in the noise at the points farther from the road region, and soft transitions between the noise values depending on the distance from the road. In order to take measures in order to decrease or eliminate noise on the main street, the local administrators and decision-makers can make use of these maps, the accuracy of which has been confirmed.  相似文献