ALBERT

Description:    El Shalal-Kema area is located east of Aswan town and Nile River. The Quaternary sediments (unconsolidated material of sands, gravels, and clays intercalation) represent the main aquifer in the studied area. Its water is under unconfined condition, and the water table is shallow (vary from 7.5 to 16.3 m). The concerned aquifer is recharged mainly from Aswan Dam Lake, from the excess irrigation water and from septic tanks, where the area is not served by sewage system. The direction of the groundwater movement is generally from south to north. The transmissivity values of the Quaternary aquifer (from three pumping tests) are relatively high (vary from 1,996 to 3,029 m 2 /day). The exploitation of groundwater is carried out where there is continuous withdrawal for industrial and domestic uses with a total average quantity of groundwater of 71,304 m 3 per day (25.67 million m 3 per year). The hydrochemical characteristics of the Quaternary aquifer is studied based on the chemical analysis of 29 groundwater and four surface water samples collected from different sites. The chemical composition of the groundwater is dominated by calcium Ca 2+ from the cations and bicarbonate (HCO 3 − ) from the anions, and the order of cation abundance is Ca 2+ 〉 Na + 〉 Mg 2+ 〉 K + and HCO 3 − 〉 SO 4 2− 〉 Cl − among the anions. The groundwater types are normal chloride water, normal sulfate water, and normal carbonate water. The hypothetical salt combination revealed the presence of different salts arranged in terms of their predominant as Ca(HCO 3 ) 2 , Mg(HCO 3 ) 2 , NaCl, Na 2 SO 4 , MgSO 4 , KCL, NaHCO 3 , MgCl 2 , CaSO 4 , and K 2 SO 4 . The analytical measurements to the NO 2 and NH 3 reveal that their values decrease in summer and increase in winter due to the stoppage of pumping which leads to the increase of the wastewater quantities that reach the groundwater. The chemical and microbiological analyses show that the aquifer in this area is contaminated with fecal and disease-causing bacteria. The main cause of this contamination is the outflow from the septic tanks; therefore, the construction of sewage network is a vital solution. Chlorination is important to disinfect the groundwater at the tanks before its distribution to the houses. Content Type Journal Article Pages 1-22 DOI 10.1007/s12517-011-0363-y Authors Ali Mohamed Ali Hamdan, Geology Department, Faculty of Science in Aswan, South Valley University, Aswan, Egypt Ahmed Ragab Abdel Rady, Chemistry Department, Aswan Water and Sanitation Company, Aswan, Egypt Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    Paleozoic successions in Saudi Arabia are exposed around and bordering the south, north, and northeastern edge of the Arabian shield. They are represented by the Wajid group in the south and by the Taymah, Tabuk, Qalibah, Huj, and Buraydah groups in the north and northeast. The Wajid group includes Dibsiyah, Sanamah, Khusayyan, and Juwayl formations. The Taymah group includes Siq, Amai’er, Quweira, Saq, and Qasim formations. The Tabuk group includes Zarqa, Sara, and Hawban formations. The Qalibah group includes Baq’a, Qusaiba, and Sharawra formations. The Huj group includes Tawil, Jauf, and Jubah formations. The Buraydah group includes Berwath, Unayzah, and Khuff formations. The Wajid group form one block in the south and the other groups form another block in the north, and they can be correlated. There are similarities between the northern belt which consists of the Cambro-Ordovician formations of the Tayma and Tabuk groups and the southern belt which consists of the Dibsiyah and Sanama formations of the Wajid group. Similarities include sandstone composition, sedimentary environment, paleocurrent directions, unconformities, tectonic events, and influence of Gondwana glaciations. These formations and probably some or all the rest of the Paleozoic formations used to form one block but later separated after erosion caused by gradual tectonic growth, uplift, and prominence of the Arabian shield. During early Paleozoic time, the process started by poststabilization then sedimentation and at a later stage the growth and uplift of the shield occurred gradually. Growth of shields is a fact and it is the only way to explain the exposure of the Wajid sandstone on top of the highest mountain of the shield which exceeds 3,000 m in As Sawdah in Asir area in southwestern Saudi Arabia. The sandstone sediments of these outcrops were deposited on a low lying basin before been raised to this elevation. Content Type Journal Article Pages 1-9 DOI 10.1007/s12517-011-0368-6 Authors Mohammad Eesa Al-Dabbagh, Department of Geology and Geophysics, College of Science, King Saud University, Riyadh, Saudi Arabia Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    Several studies demonstrate that North Atlantic Oscillation (NAO) has dominant influence on the variability of climate over Southwest Asia. We deconstruct the NAO into its two components, the Azores High and the Icelandic Low. Regional circulations are influenced by changes not only in the pressure but also the positions of the Azores High and the Icelandic Low. The results presented in this paper exhibit that significantly great portions of interannual variance of winter precipitation over Indo-Pak Region (consists of Northeast Pakistan and Northwest India) can be explained by including the contributions of the Icelandic Low pressure in addition to ENSO and AO. This contribution also explains the physical mechanisms to establish the relationships between the COA and regional climate by examining composite maps of large-scale circulation fields using NCEP/NCAR reanalysis data. Content Type Journal Article Pages 1-6 DOI 10.1007/s12517-011-0355-y Authors Muhammad Jawed Iqbal, Department of Mathematics, University of Karachi, Karachi, 75270 Pakistan Kashif Ilyas, Institute of Space and Planetary Astrophysics, University of Karachi, Karachi, 75270 Pakistan Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    The new global gravity models represented by global spherical harmonics like EGM2008 require a high degree and order in their coefficients to resolve the gravity field in local areas; therefore, there are interests to represent the regional or local field by less parameters and to develop a parameter transformation from the global model to a local kind of spherical harmonic model. The authors use local spherical cap harmonics for the regional gravity potential representation related to a local pole and a local spherical coordinate system. This allows to model regional gravity potential with less parameters and less memory requirements in computation and storage. From different kinds of representations of spherical cap harmonics, we have selected the so-called adjusted spherical cap harmonics (ASCH). This is the most appropriate for the presented mathematical model of deriving its coefficients from global gravity models. In that way, the global gravity models can fully be exploited and mapped to regional ASCH, in particular with respect to the computation of regional geoid models with improved solution. Content Type Journal Article Pages 1-7 DOI 10.1007/s12517-011-0352-1 Authors Ghadi K. A. Younis, Institute of Applied Research (IAF), Hochschule Karlsruhe, Karlsruhe, Germany Reiner Jäger, Research Group Geomatics (FFG), Institute of Applied Research (IAF), Hochschule Karlsruhe, Karlsruhe, Germany Matthias Becker, Institute of Physical Geodesy (IPGD), Technical University of Darmstadt, Darmstadt, Germany Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    A hydrogeochemical investigation was conducted in a coastal region of Cuddalore district to identify the influence of saltwater intrusion and suitability of groundwater for domestic and agricultural purposes. The geology of the study area comprises of sandstone, clay, alluvium, and laterite soils of Tertiary and Quaternary age. A total of 18 groundwater samples were analyzed for 14 different water quality parameters and the result indicates higher concentrations of ions like Cl (3,509 mg/l), Na (3,123 mg/l), and HCO 3 (998 mg/l) when compared with WHO, BIS, and ISI standards. A positive correlation ( r 2  = 0.82) was observed between Na and Cl, indicating its sources from salt water intrusion. Three factors were extracted with a total variance of 64% which indicates the sources of salinization, cation exchange, and anthropogenic impact to the groundwater. The Piper trilinear diagram indicates both Na–Cl and mixed Na–HCO 3 –Cl-type, indicating that groundwater was strongly affected by anthropogenic activities. The plot of (Ca + Mg)/(K + Na) indicates evidences of cation exchange and salt water intrusion. The (Ca–0.33*HCO 3 )/ SO 4 plot indicates salt water intrusion for elevated SO 4 levels rather than gypsum dissolution. The spatial distribution of total dissolved solid indicates the saline water encroachment along the SW part of the study area. As per sodium adsorption ratio (SAR), 50% of the samples with 〈10 SAR are suitable for irrigation and 〉10 SAR indicates that water is unsuitable for irrigation purposes. The residual sodium carbonate classification indicates that 50% of the samples fall in safe and 50% of the samples fall in bad zones and prolonged usage of this water will affect the crop yield. The Chloro Alkaline Index of water indicates disequilibrium due to a higher ratio of Cl 〉 Na–K, indicating the influence of salt water intrusion. The Permeability Index of the groundwater indicates that the groundwater from the study area is moderate to good for irrigation purposes. Content Type Journal Article Pages 1-14 DOI 10.1007/s12517-011-0351-2 Authors K. Srinivasamoorthy, Department of Earth Sciences, Pondicherry University, Pondicherry, 605 104 India M. Vasanthavigar, Department of Earth Sciences, Annamalai University, Annamalai Nagar, 608 002 Tamilnadu, India K. Vijayaraghavan, Department of Earth Sciences, Annamalai University, Annamalai Nagar, 608 002 Tamilnadu, India R. Sarathidasan, Department of Earth Sciences, Annamalai University, Annamalai Nagar, 608 002 Tamilnadu, India S. Gopinath, Department of Earth Sciences, Annamalai University, Annamalai Nagar, 608 002 Tamilnadu, India Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    The crucial and difficult task in landslide susceptibility analysis is estimating the probability of occurrence of future landslides in a study area under a specific set of geomorphic and topographic conditions. This task is addressed with a data-driven probabilistic model using likelihood ratio or frequency ratio and is applied to assess the occurrence of landslides in the Tevankarai Ar sub-watershed, Kodaikkanal, South India. The landslides in the study area are triggered by heavy rainfall. Landslide-related factors—relief, slope, aspect, plan curvature, profile curvature, land use, soil, and topographic wetness index proximity to roads and proximity to lineaments—are considered for the study. A geospatial database of the related landslide factors is constructed using Arcmap in GIS environment. Landslide inventory of the area is produced by detailed field investigation and analysis of the topographical maps. The results are validated using temporal data of known landslide locations. The area under the curve shows that the accuracy of the model is 85.83%. In the reclassified final landslide susceptibility map, 14.48% of the area is critical in nature, falling under the very high hazard zone, and 67.86% of the total validation dataset landslides fall in this zone. This landslide susceptibility map is a vital tool for town planning, land use, and land cover planning and to reduce risks caused by landslides. Content Type Journal Article Pages 1-12 DOI 10.1007/s12517-011-0356-x Authors E. Ramani Sujatha, SASTRA University, Thanjavur, Tamil Nadu, India Victor Rajamanickam, SASTRA University, Thanjavur, Tamil Nadu, India P. Kumaravel, SASTRA University, Thanjavur, Tamil Nadu, India E. Saranathan, SASTRA University, Thanjavur, Tamil Nadu, India Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    This experimental study deals with the effect of the overconsolidation ratio on the monotonic undrained shear behavior of silty sand. The study is based on the undrained monotonic triaxial tests for the overconsolidation ratios (OCR = 1, 2, 4, and 8), with different silt contents ranging from 0% to 40%. The laboratory tests were carried out at an initial relative density of Dr = 50%. The paper is composed of two parts. The first one presents the tested soils; the second one gives an analysis of the test results and discusses the influence of the overconsolidation ratio on the shear strength of the soil. The test results indicate that the shear strength of the soil increases with the increase of the overconsolidation ratio resulting in an increase of soil dilatancy. The increase in the amount of fines from 0% to 40% increases the phase of the contractancy and consequently reducing the phase of dilatancy of the tested material Content Type Journal Article Pages 1-11 DOI 10.1007/s12517-011-0365-9 Authors Ahmed Djafar Henni, Civil Engineering Department, University of Chlef, Route de Sendjas, BP 151, 02000 Chlef, Algeria Ahmed Arab, Civil Engineering Department, University of Chlef, Route de Sendjas, BP 151, 02000 Chlef, Algeria Mostefa Belkhatir, Civil Engineering Department, University of Chlef, Route de Sendjas, BP 151, 02000 Chlef, Algeria A. Saaed Hamoudi, Civil Engineering Department, University of Chlef, Route de Sendjas, BP 151, 02000 Chlef, Algeria Hamid Khelafi, Civil Engineering Department, University of Sciences and Technology, BP 1505, El-Menouar Oran, Algeria Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    To properly understand seismic wave propagation in unconsolidated sand layers, it is important to estimate the parameters of their continuous velocity–depth functions. This study proposes a procedure to estimate the V 0 and k parameters of a specific velocity function, where V 0 is the direct P-wave velocity at the ground surface and k is the velocity gradient. The V 0 and k parameters are generally independent of each other. However, it is possible to relate them numerically because both depend strongly on the porosity (ϕ) and water saturation ( S w ). The proposed procedure starts by tabulating V 0 and k for 0.05 ≤ ϕ ≤ 0.5 sampled at Δϕ = 0.05 and S w  = 0.6, so that only V 0 is needed for fitting. Then, time–distance (T-X) type curves of the direct arrival are calculated for the corresponding values of V 0 and k parameters values. The type curves are fitted then to the observed shot gather through a modification of the classic semblance velocity analysis method. Once the best-fit V 0 value is found, the corresponding k , ϕ, and S w values are picked from a V 0 – k –ϕ lookup table. The procedure is applied on synthetic shot gathers with various amounts of additive Gaussian random noise. Results show that the method is robust and tolerant to low to moderate amounts of noise. Content Type Journal Article Pages 1-8 DOI 10.1007/s12517-011-0296-5 Authors Abdullatif A. Al-Shuhail, Earth Sciences Department, King Fahd University of Petroleum and Minerals, KFUPM Box 5070, Dhahran, 31261 Saudi Arabia Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    Water quality data are required in order to compare chemical water analyses and identify water masses. R-mode factor analysis, a popular multivariate statistical tool, has been effectively used for groundwater quality studies. In this paper, the R-mode factor analysis was applied to 50 groundwater samples collected from pumping wells in the Sangan-Khaf basin which is located in the southeast of Mashhad, northeast Iran. The groundwater samples were analysed for chemical parameters. The factor analysis was then performed on the chemical data set. It can be suggested that four factors in R-mode analysis explain more than 94.31% of the total variance. The contribution of each factor at sample points, factor score, was calculated. The spatial distribution of the factor scores for each factor was mapped separately. Since the Sangan iron mine south of the study area probably affects groundwater aquifer, therefore, such studies can be used to manage the groundwater quality in the study area. Content Type Journal Article Pages 1-8 DOI 10.1007/s12517-011-0367-7 Authors Ahmad Aryafar, Faculty of Engineering, Department of Mining Engineering, Birjand University, P.O. Box 97175-376, Birjand, Iran Faramarz Doulati Ardejani, Faculty of Mining, Petroleum and Geophysics, Shahrood University of Technology, P.O. Box 36155-316, Shahrood, Iran Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511

Description:    Agriculture sector by using 80% of freshwater is the greatest water consumer in Iran. Excessive use of agricultural fertilizers in last decade, caused accumulation of enormous amounts of salts and subsequence declined the physical properties of soil. In desert and dry regions such as Rafsanjan plain, use of the groundwater resources is more than the surface water resources. Therefore, information about the quality of these resources remains a necessary task for optimum management, protection of water resources, and stopping the future damages. In this study, the groundwater quantity and quality of Rafsanjan plain was investigated by MODFLOW and MT3DMS. The presented quantitative model for this aquifer was compared by observed data and calibrated. This model was used to predict a 10-year period. Results show that water elevation decreases approximately 15 m for 10 years to come in this plain. Qualitative model results show that most quality parameters will increase. Electrical conductivity will increase more than other parameters. As values of this parameter will reach 16,000 µs/l for next 5 years. Therefore, we suggest that exploitation of water from these resources should be reduced and discharge from some of agricultural wells stop; also we suggested that recharge to groundwater resources should be increased and agricultural activities should be limited or improved using of modern irrigation systems in this plain. Content Type Journal Article Pages 1-12 DOI 10.1007/s12517-011-0364-x Authors Mohammad Bagher Rahnama, Water Engineering Department, Shahid Bahonar University of Kerman, 22 Bahman Blv., Kerman, Iran Abbas Zamzam, Water Engineering Department, Shahid Bahonar University of Kerman, 22 Bahman Blv., Kerman, Iran Journal Arabian Journal of Geosciences Online ISSN 1866-7538 Print ISSN 1866-7511