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One of the world's most pressing needs today is access to groundwater. Although hydrological parameters can generally be estimated using underground studies, these methods are time-consuming and expensive. By taking the direct relationship of these parameters with electrical resistivity and measuring it with a cheaper and faster geoelectric method, a qualitative estimate of these parameters will be obtained. The electrical resistivity method is one of the most widely used methods to probe aquifers. The main objective of this paper is to show how, by interpreting and modeling the data of this exploratory method along with other geological information, the hydrogeological modeling of groundwater reservoirs can be done, and then, with an informed vision, the wells can be drilled for exploitation. For this purpose, the electrical resistivity data at 189 points and 9 profiles in the Shahroud region with Schlumberger array, after reviewing and making some modifications, were subjected to one-dimensional inverse modeling. According to the peripheral vision, the electrode distance was considered to be 50 meters and the length of the profiles is different. The longest profile was 1000 meter and related to profile 3. Then, using the results of modeling along with other available information, the hydrogeological models of the area were prepared in the form of iso-resistivity contour map and interpreted in terms of resistivity and thickness of subsurface layer using computer software Geographic Information System (GIS). Similarly, the thickness map of the aquifer unit (s) was also prepared to classify the good and poor zones. Using the prepared models and also considering the direction and piezometric of the groundwater flow inside the aquifer, suitable places were identified and suggested for future exploitation. [ABSTRACT FROM AUTHOR]

Mining activities are liable to injuries and different types of diseases. The occurrence of an accident threatens safety in dimension stone mines. Therefore, the safety risk assessment in such mines is an important issue that needs special consideration. In this paper, the safety risk of incidents in dimension stone mines in Iran is evaluated using the fuzzy inference system. The fuzzy analytical hierarchy process is used to identify the importance degree of each incidence and then, the overall risk priority number is calculated based on the fuzzy inference process. The results of this study show that vehicle traffic and wire rupture are the most hazardous incidents. [ABSTRACT FROM AUTHOR]

The morphotectonic analysis is a useful time-saving and cost-effective method to assess tectonic activity, especially in large regions. In this paper, the morphotectonic study was carried out in Kerman city which is in the southeast of Iran and is a part of the Central Iran structural zone. Despite the occurrence of numerous historical and instrumental earthquakes around Kerman city, there is a gap in earthquake records of this city that has obscured its seismicity status. The aim of this study is to identify active faults and the associated seismic hazard to Kerman city. For this purpose, seven geomorphic indices namely stream length-gradient index (SL), drainage basin asymmetry (Af), hypsometric integral (Hi), ratio of valley-floor width to valley height (Vf), index of drainage basin shape (Bs), index of mountain front sinuosity (Smf) and Transverse Topographic Symmetry Factor (T) were examined for 51 basins of the study area, using digital elevation model (DEM) and geological maps in a GIS environment. Then, two kinds of relative tectonic activity indices were calculated for each basin, i.e., Iat and Iat_T, from the combination of these indices. The Iat_T was chosen because its results show better agreement with the structural geology and seismic records of this region. Finally, the study area was divided into three regions according to the Iat_T values. The morphotectonic analyses indicate that the Kuhbanan fault system, especially its southern splays, has the potential to produce serious seismic hazards to Kerman city in the future; the Mahan-Jupar fault-related folds, the southern tip of the Jorjafk fault, the probable fault of Zangi-Abad, the Rafsanjan-Zarand fault system, and Gowk fault are considered as other threats to Kerman city. Furthermore, this study reveals that morphotectonic analysis is a reliable tool to evaluate fault capability and to determine the fault types, and therefore to estimate seismotectonic hazard. [ABSTRACT FROM AUTHOR]

In this study, we tried to estimate the optimum linear equations among the parameters associated with different earthquake fault mechanisms for Iranian earthquakes. For this purpose, we tested different curve fitting methods in order to present the most proper empirical relationships between several seismic parameters for different fault systems. In the present paper, 46 large and destructive Iranian earthquakes whose magnitudes change between 5.8 and 7.8 from 1900 to 2014 were used for the analyses. A comparison was made by using four types of curve fitting techniques. The estimation procedures are considered as (1) L2 or Least Squares Regression, (2) L1 or Least Sum of Absolute Deviations Regression, (3) Robust Regression and, (4) Orthogonal Regression. Confidence intervals were selected as 95% for all types of regression relationships. In the selection of the best probability distribution, we considered the correlation coefficients of the linear regressions as a powerful and conceptually simple method. Correlation coefficients of all relationships change between 0.299 and 0.986 with Orthogonal regression, between 0.168 and 0.792 with L1 regression, between 0.059 and 0.829 with Robust regression. For Iranian earthquakes, the most suitable and reliable empirical relationships between moment magnitude (Mw) and surface wave magnitude (Ms), Mw and surface rupture length (SRL), Mw and maximum displacement (MD), and SRL and MD were obtained by Orthogonal regression since it supplies stronger correlation coefficients than those of the other regression techniques in most estimates. The results show that estimated empirical relationships among the different fault parameters by using the Orthogonal regression method can be accepted as more up-to-date and more appropriate in comparison with the other regression norms. Consequently, these equations were suggested as more reliable in the estimation of the maximum surface displacement, maximum surface rupture length and associated with the maximum credible earthquakes for different areas of Iran. Furthermore, obtained relationships can be statistically significant for the assessment of seismic, tectonic and geologic activities, and they can be used to evaluate the rupture hazard of the Iranian Plateau. [ABSTRACT FROM AUTHOR]

This paper describes the results of engineering geological investigations and rock mechanics studies carried out at the proposed Chamshir dam site. It is proposed that a 155 m high solid concrete gravity-arc dam be built across the Zuhreh River to the southeast of the city of Gachsaran in south-western Iran. The dam and its associated structures are mainly located on the Mishan formation. Analysis consisted of rock mass classification and a kinematic analysis of the dam foundation's rock masses. The studies were carried out in the field and the laboratory. The field studies included geological mapping, intensive discontinuity surveying, core drilling and sampling for laboratory testing. Rock mass classifications were made in line with RMR and DMR classification for the dam foundation. Dam foundation analysis regarding stability using DMR classification and kinematic analysis indicated that the left abutment's rock foundation (area 2) was unstable for planar, wedge and toppling failure modes. [ABSTRACT FROM AUTHOR]