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111.
Omer Iqbal Mirza Shahid Baig Shahab Pervez Muhammad Iqbal Siddiqi 《Journal of the Geological Society of India》2018,91(1):57-66
The project area lies in the southern part of the Hazara Kashmir syntaxis. The Hazara Kashmir syntaxis is an antiformal structure. The project area includes Rumbli, Namb, Chatrora, Chachan, Panjar, Barathian and Utrinna areas of Rawalpindi and Sudhnoti districts. The southeastern limb of the Hazara Kashmir syntaxis is imbricated along Punjal thrust, Main Boundary thrust and Riasi fault. The Jhelum fault truncates the western limb of Hazara Kashmir syntaxis. The core of syntaxis comprises of Himalayan molasse deposits. These molasse deposits represent the part of cover sequence of Indian plate. These Himalayan molasse deposits include the Early to Middle Miocene Kamlial Formation, Middle to Late Miocene Chinji Formation, Late Miocene Nagri Formation and Late Miocene Dhok Pathan Formation. The area is highly deformed resulting folds and faults. The major folds in the project area are the Panjar anticline, Barathian syncline, Barathian anticline, Rumbli anticline, Chatrora antiformal syncline and Namb syncline. The folds are either northwest-southeast trending or southwestnortheast trending. The folds are asymmetric, open, and gentle and close in nature. The folds are southwest, northeast or southeast vergent. The Jhelum fault truncates the northeast and northwest trending structures. The folds and faults are the result of northeastsouthwest or northwest-southeast Himalayan compression. 相似文献
112.
Mohamed El Kashouty 《Arabian Journal of Geosciences》2013,6(1):55-76
A robust classification scheme for partitioning groundwater chemistry into homogeneous groups was an important tool for the characterization of Eocene limestone aquifer. The aquifer locally is composed of chalky limestone with thin clay intercalated (Samalut Fm.), the fissures, the joints, and the fractures are represented the conduits of the aquifer system. The flow patterns are conditioned by karstification processes which develop a conduit network and preserve low permeability microfractured blocks. The aquifer is mainly recharged by surrounding aquifers and agricultural wastewaters. The groundwater flows in the eastern part (due the Bahr Yossef and River Nile), which is a discharge area rather than a recharge. Twenty-eight groundwater samples was collected from the Eocene limestone aquifer and analyzed for isotopes, major, and trace elements. δD and δ18O concentrations ranged widely due to geology, infiltration of different surface waters, evaporation, and hydrogeology. The concentration of δD and δ18O isotopes is depleted in the northern zone of the northern part and western zone of the central and southern part of the study area. They are enriched due the eastern area of the central and southern part of the study area. δD vs. δ18O delineate the Pleistocene aquifer and has a strong influence than other waters on aquifer hydrogeochemistry. It is confirmed by the AquaChem outputs of the mixing proportions of different water types included in the aquifer system. Cl-δD and Cl-δ18O relationships indicate the role of evaporation especially due the eastern area of the central and southern part of the study area. This research tests the performance of the many available graphical and statistical methodologies used to classify water samples. R-mode clustering, correlation analysis, and principal component analysis were investigated. All the methods were discussed and compared as to their ability to cluster, ease of use, and ease of interpretation. Nearly most low-salinity waters are in equilibrium to supersaturate with respect to both carbonate minerals, while it is shifted to undersaturate with salinity. The inverse modeling findings clarify that the calcite, gypsum, and anhydrite dissolution increased due the northeastern area, middle zone, and southern corner of the northern, central, and southern part of the study area, respectively. The latter areas also were characterized by the lowest precipitation of the dolomite. Such areas are distinguished by much more enhancement for aquifer permeability and therefore transmissivity. The latter areas can be use as injection zone by fresh water. It can be a triple function; firstly, it recharges the saline Eocene limestone aquifer through the enhancement hydraulic conductivity and dilutes it. Secondly, it enhances much more the aquifer permeability and therefore the transmissivity. The Eocene limestone aquifer can be improved in quality and quantity by using such a model and exploits it as an alternative water resource with Quaternary aquifer and Nile water. Thirdly, it irrigates more areas to increase the income/capita. The dedolomitization represents the main hydrogeochemical process in the aquifer system. The geomedia (limestone, clay, marl, shale, and sand deposits) are in contact with water, therefore, the rock/water interaction, mixing, and ion exchange were estimated by the geochemical evolution of the groundwater systems. 相似文献
113.
G. Suresh S. H. Wankhade Mohamed Shareef Vivek P. Malviya Binod Kumar M. Mohan 《Journal of the Geological Society of India》2013,81(2):151-157
A meteorite shower occurred in Katol (21° 15′ 30″ N; 78° 35′ 00″ E; at an elevation of 415 m above msl), Nagpur district of Maharashtra state, India on May 22, 2012 between 14:00 to 14:30 hrs (Indian Standard Time) with a presently observed strewn field of ~5.0 sq km area. The event was experienced by the hundreds of inhabitants with a loud noise and fire ball between Akola in the west to Nagpur in the east. The Geological Survey of India has so far collected 27 meteorite pieces with a total weight of 3500 gm. The locations, size, shape and surface features of the individual meteorite pieces have been recorded. Based on their physical properties, mineralogy, mineral chemical mapping and REE chemistry, the Katol meteorites have been classified as olivine-rich H5 type differentiated stony meteorite with reconstituted chondrules. The preliminary evidence suggests the presence of pre-solar grains in Katol meteorite. 相似文献
114.
Serpentinites are widespread in the Arabian-Nubian Shield (ANS) of the Eastern Desert of Egypt and usually enclose a tremendous carbonate alteration. Combined investigation of the stable isotope compositions of both O-H in serpentines and O-C in the whole-rock and the chemistry of the fluid-mobile elements (FMEs) in whole-rock serpentinites from Wadi (W.) Alam, Gabal (G.) El-Maiyit, and W. Atalla (Eastern Desert of Egypt) allowed to better understand the subsequent fluid sources of serpentinization and carbonation, as well as impact of these processes on the geochemistry of protolith ultramafic rocks. δ 18O values of W. Alam and W. Atalla serpentine minerals are close to the unaltered mantle and propose a lower temperature serpentinization if compared with those of G. El-Maiyit rocks. Moreover, δD values of W. Alam and W. Atalla serpentines (? 94 to ? 65‰) correspond to an igneous source that might be hydrothermal solutions mixed with the seawater in the mid-ocean ridge-arc transition setting. On the other hand, G. El-Maiyit serpentine is more depleted in 18O (with lower δ 18O values = 4.08–4.85‰), and its δD values (? 73 to 56 ‰) are most probably caused by an interaction with metamorphic fluids, acquired during on-land emplacement of oceanic peridotites or during burial in fore-arc setting. In addition, the oceanic oxygen isotope composition of most studied ophiolitic serpentinites points to the preservation of the pre-obduction δ 18O signatures and thus local-scale fluid flow at low water/rock ratios. Serpentinization fluids were CO2-poor and the carbonation of the serpentinites resulted from infiltration of externally derived fluids. δ 18OVSMOW values of carbonates in the studied serpentinites vary between heavier oxygen isotope composition in G. El-Maiyit samples (av. = 25.32‰) to lighter composition in W. Alam samples (av. = 19.43‰). However, δ 13C values of all serpentinites point mantle source of carbon. This source might have been evolved in mid-ocean ridge (W. Atalla) and subduction zone (W. Alam and G. El-Maiyit) settings. The studied serpentinites are usually enriched in FMEs, particularly Pb, Sr, Cs, and U. These enrichments were most probably the result of serpentinization and/or carbonation. 相似文献
115.
Mohamed Salah Sedek Omar Mohamed Mohamed Al Mahdy 《Arabian Journal of Geosciences》2013,6(7):2261-2283
This paper deals with a geological modeling based on seismic and well data of the Razzak Oil Field, located in northwestern desert of Egypt aimed mainly at improving the knowledge on inversion tectonics in the sedimentary basin corresponding to the oil field. Contour maps of significant seismic horizons corresponding to the top of Meso-Cenozoic formations which represent the stratigraphic traps of the oil field (top Apollonia, top Abu Roash “G,” top Bahariya, and top Alamein) are presented. The final model consists of geological cross-sections showing the inversion basin in the Razzak Oil Field. From the seismic data interpretation and modeling, we have different results matching with regional tectonic and transcurrent motion model. There are two main fault trends: the first one was northeast–southwest matching the Jurassic rift where the Jurassic is characterized by normal faults that formed in conjunction with the opening of the Neo-Tethys, and the other fault trend is northwest–southeast matching with Cretaceous faults. This is followed by a period of compressive tectonism (Syrian Arc deformation) in which two of the Jurassic normal faulted blocks (one at the northern part and the other at the southern part of the Qattara–Alamein ridge in the Razzak field) are reactivated as reverse faulted by Eocene–Early Oligocene time. 相似文献
116.
Wael Ahmed Mohamed Abdel Kawy Islam H. Abou El-Magd 《Arabian Journal of Geosciences》2013,6(7):2299-2311
Overpopulation and food security are the main global problems alert decision makers. In developing countries, such problem put extra pressure for horizontal expansion for agricultural development. The rapid sprawl of urbanized areas on the alluvial land of the River Nile and delta to accommodate the population growth has encouraged governmental and private sector for agricultural expansion in the desert. Unless there are reliable information and accurate studies for land and soil suitability, there will be a collapse of such investment. To evaluate the potential suitability of soil for agriculture development in areas of the western desert, satellite images, geographic information, and field survey including soil profiles and artesian water samples with laboratory analysis were integrated to classify the soils according their suitability for specific crop. The main land qualities of the different mapping units and the crop requirement were rated and matched to obtain the current and potential land suitability using Automated Land Evaluation System “ALES”. The study found that the main physiographic units are plateaus, hilland, mountain, and depression floor. But there are three limiting parameters for land suitability which are the lack of nutrient elements, wind erosion vulnerability, and soil texture. The study concluded that the best crops adapted with the soil conditions and could be feasible for economic use are: (1) native vegetation such as agol, sand trees, sammar, halfaa, bawaal, qordaob, bardi, and qortom; (2) filed crops such as onion, garlic, watermelon and wheat; and (3) fruits such as olive and date palms. 相似文献
117.
Mohamed Dass Amiour Hamid Mezghache Brahim Elouadi 《Arabian Journal of Geosciences》2013,6(2):309-319
The study of the organic matter (OM) associated with the phosphate ore of Kef Essennoun deposit (Djebel Onk mining basin, Algeria) was with a view to determine the decomposition degree of the OM within the pellets and the matrix, and the conditions of diagenesis. The sedimentary phosphates of this deposit are constituted of sub-rounded, phosphate-rich grains (pellets) dispersed in a surrounding, much poorer than pellets in P, matrix (or gangue). The survey of the OM associated with both pellets and matrix used several types of analyses: scanning electron microscopy (SEM), scanning electron microscope with energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The results show the OM, dispersed approximately homogeneously, in the form of large flat particles, within the gangue and within the phosphatic pellets in the form of small particles. The O/C ratio showed that the OM is more oxidised in the matrix than within the pellets. The oxidation increased with the phosphatisation rate of the pellets and more with the carbonation rate of the matrix, but it decreased with the silicification degree in the siliceous carbonated matrix. Two major functional classes were distinguished within pellets: aliphatic and oxygenated ones, the latter being fundamentally present in humic OM. The presence and abundance of these humic compounds in pelletal phosphorites are known from the 1980s and considered as witnessing a formation of apatite in a strictly closed environment, inside the pellet. 相似文献
118.
Wael Ahmed Mohamed Abdel Kawy 《Arabian Journal of Geosciences》2013,6(3):733-747
The evaluation of agricultural sustainability status helps in identifying specific indicators that constrain the achievement of sustainable agriculture. The agricultural sector in Egypt is facing major sustainability constraints such as scarce land and water resources, environmental degradation, and rapid population growth as well as institutional arrangement including land tenure and farm fragmentation, agricultural administration, lack of infrastructure, and credit utilization and high interest rates. This study aims to evaluate the agricultural sustainability in some areas in Kafr El-Sheikh governorate, north of the Nile Delta; the international framework for evaluating sustainable land management was used for realizing this objective. The map of the physiographic soils of the studied area was produced depending upon Landsat ETM+ images analysis; the results indicate that the area includes three main landscapes, i.e., alluvial, lacustrine, and marine plains. The characteristics of productivity, security, protection, economic viability, and social acceptability in the different mapping units were assessed. The obtained results show that the studied area includes two different class types, the first are the lands that are marginally below the requirement of sustainability and the second are those lands that do not meet sustainability requirements. The former class is represented by the physiographic units of alluvial plain, whereas the latter class is represented by the physiographic units of the lacustrine and marine plains. The sustainability constrains in the studied area are related to the soil productivity, economic viability, and social acceptability. 相似文献
119.
Groundwater of the Tafilalet oasis system (TOS) is an important water resource in the lower Ziz and Rheris valleys of arid southeastern Morocco. The unconfined aquifer is exploited for domestic consumption and irrigation. A groundwater flow model was developed to assess the impact of climatic variations and development, including the construction of hydraulic structures, on the hydrodynamic behavior of the aquifer. Numerical simulations were performed by implementing a spatial database within a geographic information system and using the Arc Hydro Groundwater tool with the code MODFLOW-2000. The results of steady-state and transient simulations between 1960 and 2011 show that the water table is at equilibrium between recharge, which is mainly by surface-water infiltration, and discharge by evapotranspiration. After the commissioning of the Hassan Addakhil dam in 1971, hydraulic heads became more sensitive to annual variations than to seasonal variations. Heads are also influenced by recurrent droughts and the highest water-level changes are recorded in irrigated areas. The model provides a way of managing groundwater resources in the TOS. It can be used as a tool to predict the impact of different management plans for the protection of groundwater against overexploitation and deterioration of water quality. 相似文献
120.