Exploration and Mining
Mojtaba mohammadi; Seyed Mahmoud Fatemi Aghda; Mehdi talkhablou; َAkbar Cheshomi
Abstract
Description and Understanding the sedimentary environment helps a lot in the initial estimation of the engineering properties of materials and planning of geotechnical studies. Most of the quaternary sediments (coarse and fine grained) of the Isfahan city were deposited by the Zayandehrood river. Understanding ...
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Description and Understanding the sedimentary environment helps a lot in the initial estimation of the engineering properties of materials and planning of geotechnical studies. Most of the quaternary sediments (coarse and fine grained) of the Isfahan city were deposited by the Zayandehrood river. Understanding the geotechnical characteristics and subsurface development of these sediments are essential in the old sedimentary environment for a couple of reasons. Firstly, it is difficult to determine the geotechnical characteristics of coarse-grained sediments and there is uncertainty in the subsurface development of these sediments at distant locations from the Zayandehrood river. Secondly, it is development of construction and the necessity of digging underground spaces Therefore, in this study, using the geotechnical data of 384 boreholes, maps of the approximate range of coarse-grained sediments of the Zayandehrood River were prepared at depths of 5, 10, 20 and 30 m and their geotechnical characteristics were statistical analyzed by the results of laboratory and in situ tests. The results show that the geotechnical characteristics of coarse-grained sediments do not change significantly with the change of depth and the approximate range of subsurface expansion of this river has been in the past in places other than the present river route.
Exploration and Mining
Mehdi Talkhablou; Mehdi Kianpour; Seyed Mahmoud Fatemi Aghda
Abstract
In this study, the efficiency of the compressive wave velocity (Vp) geophysical method for predicting the quality of limestone mass in areas of Zagros formation, has been investigated. For qualitative classification of limestone rock masses, the Q classification system and its modified classification ...
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In this study, the efficiency of the compressive wave velocity (Vp) geophysical method for predicting the quality of limestone mass in areas of Zagros formation, has been investigated. For qualitative classification of limestone rock masses, the Q classification system and its modified classification system for sedimentary rocks (Qsrm) have been used. For this purpose, the data related to Vp, Q and Qsrm were extracted at the site of Karun 2, Karun 4, Khersan 3 and Tangeh Manshoureh dam sites and by using software interpolation methods in ArcGIS has been transformed into information layers. Using simple and multivariable regression analysis on data extracted from information layers and using Fuzzy Inference System (FIS), models for predicting Q and Qsrm in calcareous rock masses are presented. Also, to evaluate the accuracy of the obtained models, in addition to R2, performance indicators (VAF) and root mean square error (RMSE) were used. The results show that since the Qsrm index considers a wider range of massive properties, the prediction of the Qsrm value is closer to reality using geophysical methods than the Q index.
Petroleum geology
Seyed Mahmoud Fatemi Aghda; Mashaallah Taslimi; Ahmad Fahimifar
Abstract
The main aim of this study is to examine the feasibility of estimation of flow zone indicator in carbonate rocks by integration of hydraulic flow unit concept a nuclear magnetic resonance technology. The two main permeability models Timur-Cotes and mean T2 models, because of worldwide usage of these ...
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The main aim of this study is to examine the feasibility of estimation of flow zone indicator in carbonate rocks by integration of hydraulic flow unit concept a nuclear magnetic resonance technology. The two main permeability models Timur-Cotes and mean T2 models, because of worldwide usage of these models, were used for evaluating the ability of nuclear magnetic resonance to estimate the flow zone indicator. One of the most important points in this study is the use of the experimental results of the nuclear magnetic resonance in laboratory on core that is never done in Iran. In this study, 24 carbonate samples were selected, and porosity, permeability and nuclear magnetic resonance experiments were performed. Then, using the results of the porosity and permeability tests, the flow zone indicator was determined and was considered as an index for evaluating the accuracy of the nuclear magnetic resonance method. Using the parameters obtained from the nuclear magnetic resonance test and nuclear magnetic resonance permeability models, flow zone indicator was estimated and compared with the core flow zone indicator. According to the results, it seems that the nuclear magnetic resonance permeability models, with the routine coefficients, do not have the proper ability to estimate the flow zone indicator, and it is necessary to correct the coefficients according to the lithology of rocks.
Rahimzadeh Bahman; F. Masoudi; S. M. Fatemi Aghda; T. Parhizkar; A. Pour Khorshidi
Abstract
In the north of Abyek - Qazvinmain road, various volcanic units contain olivine basalt, basalt, andesitic basalt, dacite, andesite and their associated tuffs with Eocene to Quaternary age are exposed. In order to examine geochemical and petrographic features effect on pozzolan activity, five samples ...
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In the north of Abyek - Qazvinmain road, various volcanic units contain olivine basalt, basalt, andesitic basalt, dacite, andesite and their associated tuffs with Eocene to Quaternary age are exposed. In order to examine geochemical and petrographic features effect on pozzolan activity, five samples of different rocks in the area crushed and analysed by thermogravimetric method in Housing and BuildingResearchCenter. Unweathered glassy tuff s with 26.83% pozzolanic activity ranked as good quality pozzolan. Relatively weathered tuffs and dacite present pozzolanic activities in the range of 21 to 24 % and are medium quality pozzolan. Lithic tuffs with 19.70% pozzolanic activity are in the weak quality pozzolan category. Generally, tuffs and dacits with no alteration and glass in their matrix are suitable alternatives to use as pozzolane in mix cement and lithic bearing tuffs with weathering are poor in pozzolanic features and are not recommended to be used in cement composition.
J. Ghayoumian; S.M. Fatemi Aghda; O. Ataee; M.H. Davoudi; A.A. Norouzi
Abstract
In this research a Decision Support System (DSS) has been used to support decision makers for policy making regarding the landslides which typically take place around villages. Definite software was utilized to design a model which include three strategies: landslide ...
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In this research a Decision Support System (DSS) has been used to support decision makers for policy making regarding the landslides which typically take place around villages. Definite software was utilized to design a model which include three strategies: landslide stabilization, village relocation, and risk acceptance. The model introduces the optimal strategy considering four effects (i.e., cost, reduction of fatalities, peoples and local manger point of views). To determine the cost of stabilization, in the first step the stabilization method should be selected. This is also is performed using the other DSS system. In the next step, the cost of stabilization is computed. The cost for the other alternatives is also assessed. The other effects are evaluated for the other alternatives. The user can select the optimal method for a certain landslide after completing the designed questionnaires regarding engineering geological characteristics, reduction of fatalities, people and local manger point of views. The Barikan landslide in Taleghan region was studied using the model. The stabilization method was selected as the most appropriate strategy for the landslide. The selected alternative is in a good agreement with those presented as the results of site investigation.
