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121.
The raw material soil of Al-Sowera factory quarry (quarry soil and mixture) used for building brick industry was tested mineralogically, geochemically and geotechnically. Mineral components of soil are characterized by Clay minerals (Palygoriskite and chlorite) and non-clay minerals like calcite, quratz, feldspar, gypsum and halite. The raw material is deficient in SiO2, Al2O3, K2O, Fe2O3 and MgO, while enriched in CaO. Loss on ignition and Na2O are in suitable level and appear to be concordant with the standard. Grain size analyses show that the decreasing sand and clay, and increasing silt ratio in both quarry soil and mixture caused decreasing in strength of brick during molding and after firing. The quarry soil is characterized by high plasticity clayey soil of 30.49 plastic index (P.I), whereas the mixture considered a clayey soil has a low plasticity of 7.7 plastic index (P.I). To improve the chemical and physical properties of the raw material, alumina-silicate minerals rich in K2O, Fe2O3 and MgO are recommended as additive materials to the main mixture. 相似文献
122.
Journal of Seismology - 相似文献
123.
Phosphorus (P) desorption characteristics may be altered due to the biosolids decomposition during the incubation period. In our previous work we studied the phosphorus release kinetics in biosolids-amended calcareous soils with no prior incubation. The objectives of this work were (1) to assess the phosphorus desorption behavior in soils as influenced by biosolids after 5 months of incubation and (2) to evaluate the influences of six levels of the biosolids on phosphorus availability and salinity of soil. The results showed that the biosolids addition significantly increased the soil available P and salinity. The P availability and salinity of the soils increased as level of the biosolids application increased. However, there was no significant difference between some application rates for some soils. The results indicated that the incubation can affect the factors controlling the P release rate. Also, the results showed that the soil organic matter negatively affected the P desorption rate in the biosolids-treated soils. 相似文献
124.
Abdel-Monem S. Mohamed M. Saleh S. Mahmoud A. Teleab A. A. Othman Diaa Hamed 《Arabian Journal of Geosciences》2013,6(4):1283-1293
The Abu-Dabbab area is characterized by high seismicity and complex tectonic setting; for these facts, a local geodetic network consisting of 11 geodetic benchmarks has been established. The crustal deformation data in this area are collected using the GPS techniques. Five campaigns of GPS measurements have been collected, processed, and adjusted to get the more accurate positions of the GPS stations. The horizontal velocity vectors, the dilatational, the maximum shear strains, and the principal strain rates were estimated. The horizontal velocity varies in average between 3 and 6 mm per year across the network. The results of the deformation analysis indicate a significant contraction and extension across the southern central part of the study area which is characterized by high seismic activity represented by the clustering shape of the microearthquakes that trending ENE. The north and northeastern parts are characterized by small strain rates. This study is an attempt to provide valuable information about the present state of the crustal deformation and its relationship to seismic activity and tectonic setting at the Abu-Dabbab area. The present study is the first work demonstrating crustal deformation monitoring at the Abu-Dabbab area. The time interval is relatively short. Actually, these results are preliminary results. So, the continuity of GPS measurements is needed for providing more information about the recent crustal deformation in that area. 相似文献
125.
In arid and semi-arid countries worldwide, conflicts between human development activities and conservation of groundwater resources are widespread and attract many public debates. This research aims to propose groundwater management alternatives for a coastal aquifer by studying its vulnerability and in particularly the risk of seawater intrusion. An additional objective is to propose some agricultural policies aimed to conserve groundwater resources in Mahdia and Ksour Essaf. Intensive groundwater mining, for irrigation and for water drinking, has caused an overexploitation of the water resources. In addition, the degradation of water quality, caused by septic tanks and intensive agricultural activities, has given rise to notable crucial state of the groundwater resources. With the aim of tackling the groundwater degradation problem, integration into a common platform of vulnerability assessment, seawater intrusion modelling and hydrochemical analysis is proposed. This platform can considerably reflect the water resources state in order to propose some solutions reducing the contamination of the Mahdia–Ksour Essaf aquifer. The groundwater management alternatives, proposed in this study, were prepared within a geographical information system. 相似文献
126.
127.
The Neogene carbonate rocks have relatively small exposure relative to the siliciclastic and evaporite rocks in Rabigh and Ubhur areas, north Jeddah, Red Sea coastal plain of Saudi Arabia. The Miocene carbonates form small hills in both areas, which conformably overlie the siliciclastics, whereas the Pleistocene coral reefs form terraces facing the Red Sea in Rabigh area. The Neogene carbonates are represented by the following microfacies types: (1) dolomitic, oolitic, foraminiferal packstone; (2) sandy, dolomitic, intraclastic, foraminiferal packstone; (3) dolomitic and oolitic wackestone; (4) dolomitic, foraminiferal, intraclastic wackestone; (5) dolomitic mudstone; (6) coral boundstone; and (7) grainstone. The diagenetic processes affecting these carbonates are compaction, dissolution, aggrading neomorphism, and replacement that took place during deposition, shallow burial, and uplift. Pervasive dolomitization by the seepage reflux mechanism is responsible for the mimic replacement of the calcite of the original component of the limestone with dolomite. Sediments, biota, and lithofacies characteristics of the studied carbonate rocks of Rabigh and Ubhur areas indicate the presence of three facies zones; these are (1) FZ 5 platform margin reefs, (2) FZ 6 (platform margin sand shoals), and (3) FZ 7 platform interior-normal marine. The standard microfacies types are represented by (1) SMF 12, limestone with shell concentration; (2) SMF 15, oolitic wackestone and packstone; and (3) SMF 18, bioclastic grainstone and packstone with abundant benthic foraminifera. 相似文献
128.
Sepideh Saeidi Seyed Hamed Mirkarimi Marjan Mohammadzadeh Abdolrassoul Salmanmahiny Colin Arrowsmith 《国际地球制图》2013,28(12):1381-1397
AbstractThis study demonstrates the integration of landscape aesthetic quality and probable urban growth patterns in urban landscape modelling. This was performed using SLEUTH as a scenario-based urban growth model in Gorgan City of Iran. Future urbanization was predicted under developing three different scenarios including historical, managed and aesthetically sound urban growth up to the year 2030. Multi-Layer Perceptron neural network model was conducted for mapping the aesthetic suitability of the study area. The aesthetic suitability layer was used in the third scenario of SLEUTH model as the excluded layer to protect the scenic patches in future. The results showed that by correct implementation of urban growth policies, 323 ha in the second scenario and 650 ha in the third scenario would be saved. This integrated model would help the planners for a better management of urban landscapes as a Spatial Decision Support System. 相似文献
129.
A synthetic approach integrating surface and subsurface data for prospecting deep aquifers: the Southeast Tunisia 总被引:2,自引:0,他引:2
The Southeast Tunisia has remarkable thermal springs that have been used for bathing since many years. Currently, studies
are being carried out to investigate the possible use of the hot water for heating buildings and for greenhouses. Springs
with discharge temperatures between 26.8 and 58°C exist in the area. The flow rates range between 7 and 66 l/s with total
dissolved solids (TDS) varying between 2,020 and 4,030 mg/l. Both geological–hydrogeological setting and the similarity in
chemical characteristics between the Zarat spring and nearby water wells suggest that the hot water from this spring may be
related to the Senonian aquifer. However, the hydrogeothermal approach shows that the depth of the reservoir that supplies
the Zarat spring is greater than that of the Senonian aquifer. In fact, geothermometry approach indicates that fluids emerging
from the Lower Cretaceous sandstones reach temperatures of approximately 78°C at depth, while the fluid temperature from the
nearby water wells is 32°C. Through the integration of various types of data we found that the thermal water of Southeast
Tunisia is of meteoric origin. This water infiltrates deeply into the Lower Cretaceous sandstones and reaches a high temperature
before rising upwards to supply the hot springs and well discharge zones. It appears that the upward movement of hot water
from the deep aquifers to shallow ones is probably due to the abundant fractures in the area. 相似文献
130.
Hamed Ameri 《Arabian Journal of Geosciences》2018,11(3):66
The Jurassic successions represent a wide distribution in North of the Kerman province. These successions include Ab-Haji, Badamu, and Hojedk formations. The Hojedk Formation contains the plant fossils. The Lenjan section is one of the suitable areas for paleontological studies on the Hojedk Formation. The study section is mostly composed of green sandstone and shale with several interbedded coal veins with different thicknesses. The thickness of the Hojedk Formation is about 200 m in the Lenjan section. In this study, seven genera and 13 species of macro plant fossils were identified and described, including Nilssonia undulata, Nilssonia bozorga, Nilssonia berriesi, Nilssonia sp., Klukia cf. exilis, Klukia exilis, Cladophlebis antarctica, Coniopteris lobata, Coniopteris murrayana, Elatocladus confertus, Podozamites sp., Equisetites sp., and Coniopteris sp. The Bajocian–Bathonian can be attributed to the Lenjan section based on the recognized flora. 相似文献