JOURNAL OF GEOTECHNICAL GEOLOGY (APPLIED GEOLOGY)
Year:2012 | Volume:8 | Issue:2|Papers Count:9

The clay minerals are a group of fine-grained minerals that are of major significance from an engineering point of view. Clay minerals comprise an essential portion of the soils and therefore have a strong influence on soil's behavior. The clay minerals consist of fine major groups (kaolinite, halloysite, illite, vermiculite and smectite). In this research, engineering properties of clay soils of Hamedan province, Western Iran have been considered for using as brick production. From an engineering point of view, the clay minerals as building materials are very important with numerous applications. It should be noted that Lalejin is a famous center for tiles production in Iran that whose productions are exported to other countries. In this research, 36 soil samples from different parts of Hamedan province were selected and physical, chemical and mechanical tests have been carried out on the samples. Based on the results, 13 soil samples have passed the standard tests successfully. These soils were selected as suitable soils for brick and tiles production.

Tepal Folding is located west of Shahrood and in the southern boundary of the Eastern Alborz range. The observed formations in the studied area have been ranged from Paleozoic to late Jurassic age. We surveyed the geological structures to have a better realization of the evolutionary history of the Alborz in this period. After geometric review of macroscopic folds and mesoscopic folds, it's revealed that macroscopic folds which have a trend tend to south and south west, are consistent with Flower Structure of Alborz. These folds were made due to the shortening of Eastern Alborz with a north-south compression, and also due to the major faults of Shahrood Fault System. Mesoscopic folds have two trends simultaneously, namely with northeast-southwest and east-west direction. Measured data from folds revealed that the first group is of the secondary order of macroscopic folds like Tepal syncline & anticline, whereas folds with east-west directions are fault related folds. Based on dip and strike of axial plane from thrust faults in the region, it could be suggested that these folds were made by north-south compression in the region.

Planning a road path requires an extensive evaluation process in order to identify the best possible path that road can follow. In planning a suitable road network, one must consider factors like gradients of the area, possible land use and soil type that cause landslide along the road path between two points especially in a forest area. The studied area in this research is situated east of Mazandaran province, southeast of Neka city, in Bandebon-Laie area. In this paper we studied the landslide that caused many problems in the studied area. Because of the large number of landslides along the old road path between Bandebon-Laie, we started to identify a new path with a high safety factor.In order to do so, some effective factors in slope instabilities were studied and investigated in this region. In addition, the geographical positions of the active landslides along this path were recorded by GPS. Finally, by using geographic information system (GIS), we have found that the digital and raster layers of the effective factors caused landslides in this region. The expected final result to be obtained in this research is a map showing the most suitable and shortest road path between two points in the studied area.

Doz-Kord irrigation canal project is of great socioeconomic significance and is one of the important projects currently running in the northwestern part of Fars Province. Considering the site location plan and the negative effect of slip phenomenon on life and the stability of hydraulic structures, a landslide risk zoning study is very important for this project. Project location consists of loose material with a relatively sharp slope and several active faults. The potential occurrence of landslides in the studied area because of rainfall climate is very high. According to parameters such as rock and soil types, distance from faults, slope of domain, distance from road axes and drainage pattern the factors in slope instability were recognized. Using digital maps, information layers of effective parameters in the slope instability were prepared in the GIS environment. Data layers were categorized and integrated in the GIS Software. Finally a landslide risk zonation map was prepared. In this map the potential landslide regions are shown separately in five categories.

The area studied in this research is a part of the River Kor in Fars province and the area is located Southern Marvdasht and 50 Km north of Shiraz city.  Since the Shiraz petrochemical plant, factories and industrial centers of Marvdasht City are based around the Kor River, environmentally destructive effects of heavy metals on the Kor River are very important. To investigate the distribution and mobility of potentially toxic elements and the origin of these in the Kor River, samples were collected at 9 stations along the river from the fine grain sediment (particles smaller than 63 microns) and were analyzed by ICP-OES method. Comparison of samples analysis with background and world standards indicated high concentration of As, Pb, Zn, Ni and Cr in some sampling stations. To estimate the intensity of pollution in the area, index of geoaccumulation (Igeo), enrichment factor (EF), pollution index (PI) and anthropogenic factor (An) are used. Correlation coefficients obtained between pollutant elements show that the elements arsenic, lead and zinc have high correlation with each other due to the same origin, release and deposition of these elements under the surface conditions along the river. This study shows that the highest concentrations of pollutants in the river of Kor are around the Shiraz petrochemical plant, Marvdasht industrial factories and urban waste water effluent entering to the river.

Karaj-Chalus road is an important connection between Tehran-Alborz provinces and west of Mazandaran County. Considering tourist attractions in the north, this road is one the most crowded roads in the country. Recently a new highway is being constructed adjacent to the previous road, therefore a large portion of the traffic will be converted to the highway. Since the highway passes the high mountainous lands the roads are enormously affected and in high risk by landslides. In this study, both mentioned ways are classified according to hazard risk. This project has been performed in two steps. First, a landslide hazard zoning map has been provided for the region around the roads to detect the high risk and low risk zones, then the roads have been divided  into segments that each of which has 2 kilometers length. The main parameters in landslide hazard zoning are considered such as topography, hydrology, geology, tectonics and green coverage. The landslide hazard map clearly represents the high risk and low risk areas but it is important to realize how it influences the roads. With purpose of classifying the road segments, the azimuth of the maximum slope of each side of the road has been considered. An aspect layer has been provided using the DEM of the region. In order to estimating the direction of the maximum grade of the ground, the mentioned aspect layer is applied. In order to determine the effectivity of the direction of the slope to the roads, the angle between the road segments and the maximum grade has have been calculated and is used as an important factor to determine the amount of risk for the road segments. The distance between the road axes to the trench of mountain also has been taken into account. According to the mentioned factors and the landslide hazard map, the road segments have been categorized into four zones based on the degree of accepted risk. In accordance with the results obtained from this research, 58 percent of the road has the potential of high and very high risk respectively. 45 percent of the highway has the potential of high and very high risk.

Calcareous nanofossils in the Abderaz Formation at Sheikh Section have been studied. This section is situated in the western part of the Kopet-Dagh Basin. In this study 34 nanoplankton species of 21 genera were identified. According to the first occurrence of index species and fossil assemblages calcareous nanofossil biozones (CC18-CC21) of Sissingh (1997) have been recognized. Based on these biozones, the age of this formation is Early Campanian-Early Late Campanian. The investigation of mentioned nanofossils shows that Abderaz basin at Sheikh Section was deposited in relatively low latitude, relatively high temperature and low productivity so that the depth of the basin to the Kalat Formation increased.

Qhalaylan intrusive body in southwest of Ghorveh with east-west trend is a small part of intrusive bodies of Sanandaj-Sirjan zone. Based on field observation as well as mineralogical characteristics, this suite consists of main unit's diorites, granites and porphyritic granite. Mineralogical and geochemical studies show that the rocks of this suite are I-type, sub-alkaline and from the point of view of saturation degree of aluminum (ASI) are metaluminous. The low amount of elements ratio (Al2O3/FeO+MgO+TiO2) and (Na2O+K2O/(FeO+MgO+TiO2) and concentration of low Rb/Sr (less than 0.6) in the dioritic rocks suggest diorites origin from the partial melting of lower crust sources without water due to melting of amphibolite. High volume of felsic rocks (granites and porphyritic granite) is inconsistent with this subject that unites an origin via differentiation of mantle-derived basaltic parent magma and assimilation. The low amount of transition elements (Ni, Cr, Co and V), and the low amount of elements ratio Nb/La and Ti/Zr show that the source of felsic magma, is presumably due to partial melting of crust protholites (metagrywakes). Discrimination diagrams for tectonic setting, the low Nb/U and Nb/Y and the high Ba/Nb show the intrusion of Qelaylan into the volcanic arc setting related to an active continental margin.