Hydrogeomorphology
najmeh Haj seyed ali khani; hamzeh saeediyan; alijan Abkar
Abstract
Underground dams can be a very suitable alternative to check dams so that in recent decades due to their privileged characteristics, they have attracted the attention of various researchers around the world. Geoelectric samples were carried out at the axle and reservoir of Dehbakri underground dam by ...
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Underground dams can be a very suitable alternative to check dams so that in recent decades due to their privileged characteristics, they have attracted the attention of various researchers around the world. Geoelectric samples were carried out at the axle and reservoir of Dehbakri underground dam by sondage putting method and with using Schlumberge array. These samples were performed during 6 profiles (P1 to P6) and 32 electric sondage. The results of geoelectric studies indicate that there is a two-layer model along the geoelectric sections that the upper layer has alluvial and the underlying layer has bedrock. Alluvial layer is divided into dry parts at the top and wet parts at the bottom. The depth of reaching groundwater level varies in different parts of the study area, but on average it can be considered 5 meters. Alluvial thickness also varies during profiles, but the highest thickness is generally in the middle parts of the geoelectric sections and more close to the right support. The highest alluvial thickness was estimated at the S26 catheter site and 13 meters. Considering the specific electrical resistance scale of the layers and considering the rock outcrops on both sides of the river, it seems that the bedrock in most places has alternating lithology made of shale, marl and sandstone and in some parts of the marl material.
Hydrogeomorphology
Davoud Mokhtari; Amir Heshmati
Abstract
Knowing the subsurface structures is one of the ways to access underground resources, and knowing the characteristics of alluvial sediments is very important for exploitation, management and control of underground water. Shahryar plain located in the west of Tehran city and south of central Alborz, which ...
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Knowing the subsurface structures is one of the ways to access underground resources, and knowing the characteristics of alluvial sediments is very important for exploitation, management and control of underground water. Shahryar plain located in the west of Tehran city and south of central Alborz, which supplies an important part of Tehran city's drinking water, is covered with Quaternary alluvium. The purpose of this article is to determine the thickness of these alluviums. There are different geophysical methods to estimate the thickness of different layers of the earth to determine the characteristics of alluvial deposits, including the type, depth, thickness, etc., of this plain, the data of electric soundings includes: 12 profiles and 186 sections, received from the regional water organization, geological maps, and data DEM used. After checking and validating the data, by choosing the normal kriging interpolation method with exponential variogram, the alluvial thickness and topography maps of the underlying layers include: alluvial thickness map, evaporite sediment surface topography, tuff and igneous rocks topography, The topography of the bedrock of the region, the thickness of evaporite sediments and the topography of the conglomerate surface of the region were preparedin in GIS with the highest accuracy. Then horizontal and vertical characteristics of these deposits were investigated. The results showed the maximum thickness of the alluvium is up to 350 meters in the center And near the edge of the plain, the thickness of alluvium decreases so that it is about 10 meters in the west and southwest.
