Hydrothermal Alteration Mapping Using ASTER Data for Reconnaissance Porphyry Copper Mineralization in the Ahar Area, NW Iran

The Ahar area is located in East Azarbaijan province, and covers an area of about 2,500 km². Spectral mapping techniques were applied on VNIR and SWIR of ASTER data for discriminating between hydrothermal alteration zones and the identification of high potential mineralized lithological unit associated with hydrothermal porphyry copper mineralization in the Ahar. In this research to remove atmospheric and topographic effects from ASTER data, the log-residual method (LRM) was used. Four methods, Relative Band Depth Ratios (RBD), Principal Component Analysis (PCA), Minimum Noise Fraction (MNF) and matched filtering (MF), were used to processing and interpretation of remote sensing data in the study area. Results show that ASTER images provide preliminary mineralogy information and geo-referenced alteration maps at low cost and with high accuracy for reconnaissance porphyry copper mineralizations.     

Evaluation of earthquake activity along the Serghaya fault, Syria, from instrumental seismic data

This is a tentative study in order to characterize and identify the Serghaya fault in Syria through an analysis of its instrumentally observed earthquake activity for the period of 1995–2009. Different approaches are used to evaluate a- and b-values of the Gutenberg-Richter relation. It has been found that the computed b-values (around 1.5) are bigger than usually expected, which could be related either to incompleteness of earthquake catalogue or to invalidity of the Gutenberg-Richter model in the case of Serghaya fault. Based on several explanations of high b-values, existing in the literature, it can be inferred that the events recorded on the Serghaya fault occurred at small depths in the heterogeneous milieus under low stresses. A relative seismic quiescence from 1900 up to now is observed, whereas the biggest earthquake recorded during the study period does not exceed magnitude 3.9. Such quiescence does not reflect accurately an earthquake potential of the Serghaya fault and can probably indicate a large-magnitude earthquake occurrence in near future. The established earthquake catalogue must be necessarily completed in order to deeper characterize the real behavior of the Serghaya fault. Such a characterization, accompanied with seismic activity evaluation, could be used in the assessment of seismic hazard.     

Groundwater potential estimation using vertical electrical sounding measurements in the semi-arid Khanasser Valley region,Syria

Abstract

Traditional and polar vertical electrical sounding (VES) techniques were used for computing and characterizing the transmissivity of the Quaternary and Palaeogene aquifers in the Khanasser Valley, northern Syria. The VES technique with its different applied approaches is inexpensive, easy and gives rapid results with high spatial resolution. The Dar-Zarrouk parameters were determined to estimate the groundwater potential of the aquifers. The results show the mean transmissivity of the Quaternary aquifer to be 49 m²/d (minimum: 10 m²/d; maximum: 131 m²/d; standard deviation: 32 m²/d), and that of the Palaeogene aquifer is 0.94 m²/d (minimum: 0.31 m²/d; maximum: 1.54 m²/d; standard deviation: 0.33 m²/d).

Editor D. Koutsoyiannis

Citation Asfahani, J., 2013. Groundwater potential estimation using vertical electrical sounding measurements in the semi-arid Khanasser Valley region, Syria. Hydrological Sciences Journal, 58 (2), 468--482.     

Quaternary aquifer transmissivity derived from vertical electrical sounding measurements in the semi-arid Khanasser Valley Region,Syria

Vertical electrical sounding technique (VES) is used as an alternative approach to pumping test for computing the Quaternary aquifer transmissivity in the Khanasser Valley, Northern Syria. The method is inexpensive, easy and gives faster results with higher special resolution than the traditional pumping technique. The hydraulic conductivity values obtained using VES agree with the pumping test results, which in the Khanasser Valley vary between the order of 0.864 and 8.64 m/day (10⁻⁵ and 10⁻⁴ m/s). The probable location of the Quaternary aquifer in the Khanasser Valley is obtained through the transmissivity map derived from VES. The knowledge of transmissivity is fundamental for modeling and management processes in the Khanasser Valley. Other similar semiarid regions can benefit from the approach successfully applied in the study area.     

High-throughput production of peroxidase and its biodegradation potential toward polymeric material

Plastics are polymeric materials, and their disposal is a great problem in today’s society. Large quantities of single-use plastics are used every minute throughout the world. Peroxidase enzymes play a significant role in the biodegradation of polymeric materials due to oxidoreductase capability. The objective is to determine which set of conditions optimize the production of peroxidase enzymes by Phanerochaete chrysosporium so as to degrade polymeric materials. The sequential order of parameters in terms of their relevant performance in the bioprocess was determined as urea > polyvinyl chloride > incubation time > polyethylene > veratryl alcohol > sucrose > ammonium sulfate > glucose > ferrous sulfate and polystyrene. Statistical analysis was performed by using analysis of variance which indicated the significance of model Plackett–Burman and components on the basis of F value and P value of 0.012678 < 0.05. The Fourier transform infrared spectroscopy of enzyme-treated polymer revealed structural changes at 1091, 1638 cm^?1. A new peak appeared at wave number 1029 and represented the aromatic ether and phenolic group as compared to control. Biosynthesis of lignin peroxidase at optimized conditions has the potential for biodegradation of recalcitrant polymeric waste, due to its oxidoreductase capability for chemically inert material in nature like lignin and can be used for waste treatment on a large scale.     

Modelling of moving bed biofilm reactor (MBBR) efficiency on hospital wastewater (HW) treatment: a comprehensive analysis on BOD and COD removal

Performance of moving bed biofilm reactor system for a real hospital wastewater (HW) was experimented, modelled, and optimized using response surface methodology. Prior to conducting laboratory tests, design of the experiments was evaluated to minimize any prediction error. Statistical analyses demonstrated the models’ validity and adequacy for anticipation of the removal of BOD and COD by the process. The models predictions (with desirability of 0.98) were found to be in very good agreement with confirmative experiments results. The results indicated that under convenient operating conditions of the studied variables (packing rate 70%, HRT 24 h, and MLSS 3000 mg/L), the removal efficiencies for BOD and COD were 97.8 and 95.6%, respectively. Moreover, kinetics of the biological process showed that removal of organic matters for the tested wastewater adheres to modified Stover–Kincannon model with a correlation coefficient of 0.998. Ratio of BOD to COD of 0.6 (optimal range for biological treatment normally is >0.5) suggests acceptable efficiency of the reactor for decomposing organic load. A high overall efficiency of the process and fulfilling the related standards make this system an appropriate option for treating HDW.     

Estimating maximum magnitude earthquakes in Iraq using extreme value statistics

Summary. Extreme value theory is used to estimate maximum magnitude earthquakes in Iraq (29–38°N, 39–48°E). The seismicity file for the period 1905–1982 is used to determine the recurrence relationship as well as the parameters of Gumbel types I and III asymptotic distributions.
The statistical parameters are estimated by both least squares and maximum likelihood techniques. Results show that although the least squares upper magnitude is closer in value to actual earthquake magnitude, the maximum likelihood approximation to the third distribution appears to show a better overall fit to the data sample. This result is reflected in the calculated probability of occurrence of earthquake risk over various design periods.     

The effect of orthorhombic anisotropy and its implication for oil recovery and reservoir exploitation

Results of an experimental study of shear‐ and compressional‐wave propagation in an orthorhombically anisotropic medium are presented. The experiments were performed on a physical model consisting of two sets of fractures. The first set consisted of orientated rubber inclusions simulating weak material‐filled cracks. The second set consisted of a system of closely spaced parallel fractures simulated by thin plates of epoxy resin, superimposed orthogonally on the first set. Three cases of fracture orientations within the model were identified and studied. Case 1 is analogous to a jointed fracture reservoir with one vertical set of fluid‐filled cracks or fractures and one non‐filled horizontal set. This case is referred to as JFV. Case 2 is analogous to a double fracture reservoir with one horizontal set of fluid‐filled fractures or cracks and one non‐filled vertical set. This is referred to as DFH. Case 3 is analogous to a double fracture reservoir with two vertical sets of fractures or cracks, with only one fluid‐filled. Case 3 is referred to as DFV. A pulse transmission method was performed on all three modelled cases along the three principal axes. A directional variation in the compressional‐ and shear‐wave velocities, as well as distinct shear‐wave splitting, was observed. The elastic constants for each case were determined and differences between them were noted and compared with the controlled results of both layered (transverse isotropy, TI) and vertically fractured (azimuthally anisotropic models, VF) media. The differences in elastic moduli and velocities indicate the potential of recognizing the different fracture orientations and suggest an approach to designing a method of drilling to further enhance oil recovery and reservoir exploitation.     

Seismic intensity zoning and earthquake risk mapping in Iraq

The recently published Iraqi earthquake data file over the period 1905–1984 is used to derive a local I _o -M _s formula. This is then combined with a local intensity attenuation relationship to compile the observed I _o (MM) zoning map for Iraq. Earthquake risk is calculated using the log N (M _s )relation for selected design magnitudes and periods and is mapped as the (%) probability of occurrence using a 0.5 deg latitude/longitude grid system. It is observed that the intensity zones and contour distributions are highly influenced by the presence of large magnitude shocks while risk maps reveal the Tauros seismogenic zone as having a greater risk of occurrence than the Zagros zone. The compiled zoning maps are intended for the use of local practising engineers for earthquake-resistant design procedures that are currently being adopted in the country.     

Biostratigraphy,Microfacies and Depositional Environment of the Sarvak Formation at the Pyun Anticline (Zagros Basin,Southwest of Iran)

The Sarvak Formation is a carbonate sequence of Late Albian–Early Turonian age in Zagros Basin in Iran. In this investigation, the Sarvak Formation at the Pyun Anticline section (Izeh Zone) has been studied. It consists of 797 m thick limestone which overlies the Kazhdumi Formation conformably and underlies the Gurpi Formation unconformably at the Pyun Anticline. A very rich fossil association (85 genera and 132 species) characterizes the Pyun section. Based on the stratigraphic distribution of diagnosed foraminifera, five biozones are established: 1, Muricohedbergella-Globigerinelloides sp. assemblage zone (Late Albian); 2, Praealveolina iberica-Chrysalidina gradata interval zone (Early Cenomanian); 3, Chrysalidina gradata-Cisalveolina fraasi (fallax) and C. lehneri interval zone (Middle Cenomanian); 4, C. fraasi (fallax) and C. lehneri-Praetaberina bingistani assemblage zone (Late Cenomanian); 5, Nezzazatinella picardi-Mangashtia- Dicyclina assemblage zone (Early Turonian). Based on the petrographic and sedimentological analyses, some 13 carbonate microfacies were identified. The investigated microfacies confirm a ramp-type paleoenvironment. These microfacies, from distal to proximal environments, consist of: MF1: planktonic foraminifera wackestone-packstone; MF2: Oligostegina planktonic foraminifera wackestone to packstone; MF3: planktonic-benthic foraminifers sponge spicules wackestone-packstone; MF4: rudist floatstone; MF5: rudist rudstone; MF6: bioclast intraclast grainstone; MF7: peloid intraclast grainstone; MF8: benthic foraminifers rudist grainstone-packstone; MF9: peloid bioclast grainstone-packstone; MF10: bioclast (benthic foraminifers) wackestone-packstone; MF11: peloid bioclast packstone; MF12: dacycladacea benthic foraminifera packstone-wackestone; MF13: miliolids wackestone-packstone.