JOURNAL OF GEOTECHNICAL GEOLOGY (APPLIED GEOLOGY)
Year:2008 | Volume:4 | Issue:1|Papers Count:8

The Kalut basin (NE of Ardakan) was formed as an intermountain depression just after Upper Cretaceous orogeny event and was severely folded in the Pliocene. The plunge of the fold axes are less than 30 degree frequently. From the viewpoint of interlimb angle, the important features of the folded Kalut basin are the open synclines and the closed diapiric anticlines with salty core. In the central parts of the basin the salt bodies have intruded along the b-axis anticlines as piercement domes. In the western and eastern zones of the basin, the interlimb angle of anticlines is “open” and in the eastern – and westernmost of the basin, the continuity of diapiric folds has ended and the thin salt beds have been deposited in the core of low amplitude folds. The axial surfaces of the folds mostly dip more than 70 degrees. The first traceable orogenic event in Tertiary beds of the basin occurred in the Middle Oligocene. The most severe folding in the kalut basin and also the greater part of the diaper upheavals were made in the Pliocene. The development of diapiric anticlines in this time has caused the upper -layer dips to about 60-85 degrees.

The Abdasht massive peridotite is a part of the Esphandagheh ophiolite complex. Constituents of the Abdasht rocks are mostly dunite and harzburgite, which occasionally convert to lehrzolite and wherlite. Chromite deposits occur in 15 mineralized horizons. Considering that some of the world's ophiolite complexes have worthwhile resources of PGM, Ni, and Co, in addition to Cr, some investigations into geochemistry and ore microscopy for identifying sulfuric minerals have been carried out. The results of these studies reveal the presence of Nickel sulfuric minerals, especially Pentlandite in this region, which is found in two different parts: host rocks of the chromite deposits and also chromite lenses. The amount of PGM is very small (at most 83 ppb in Kamalabad mine) and often exists in the form of inclusion and fine grain in chromites and silicate gangue. Other sulfuric minerals such as pyrrhotine, pyrite, millerite, chalcopyrite, chalcocite, nickel pyrite, chalcopentlandite, vallerite etc. were found. These sulfuric minerals (Ni, Co and PGM) never consist of worthwhile resources and their economic value is negligible.

Considering the importance of the resonance phenomenon in buildings and the numbers in the world of this phenomenon and the fact that this phenomenon isn' t considered yet in Kerman province, in this paper the earthquake resonance frequency range is calculated for the regions of Golbaf and Sirch, located in Kerman province, using 23 records of earthquakes that happened between 1981 and 2000. The results have been generalized for the whole province.After providing above accelerograms, a program has been written for the calculating power spectra and its smoothed curve, based on Canai-Tajimi model and its correctness checked by comparing available power spectra. The program read records respectively, and at first it calculated and exhibited total energy and power of earthquake at the end of ground motion in any frequency between zero and 25 hertz, and finally exhibited smoothed power spectra model assuming linear relationship with two neighbor points of accelerograms and direct solving of movement equations. Through all accelerograms 18 records were related to Golbaf and 5 records were related to Sirch and all of them had maximum acceleration of more than 0.05g.Resonance frequency range has been specified by earning the amount of central frequency and shape factor parameters for all the records. This range was calculated between 3.43 and 8.76 hertz. By generalization of the calculated result, to the whole province, one can say that the structures which have a main frequency range of 3.43 to 8.76 hertz increase the damage of the earthquakes. Therefore, in structural designing, the main frequency of that range should be avoided by changing the structural mass or rigidity.

The Mishan Formation (Middle Miocene) is the middle part of the Fars Group. To determine the limiting factors of reservoir potential in the Mishan Formation in Fars Province, three geological cross sections in western Fars and a comparative one southwest of Boushehr have been studied. In these sections the Mishan Formation consists of shale, marl and sandstone and limestone facies. Poorly developed primary and secondary porosity features on the one hand, and occurrence of porosity decreasing diagenetic processes such as cementation, compaction, calcite and silica fillings and also bioturbation on the other hand lead to absence of sufficient porosity in these deposits.

Muteh goldfield is located in 295Km S-SW of Tehran and 70 km of Delijan city in central Iran, is very important for Iran’s annual gold production rate. There are 9 recognized gold deposits but, according to tonnage, Au grade, economic factors, geologic and engineering parameters, gold is extracted from only 2 deposits: Chahkhatoon and Senjedeh. There is a big problem because the gold reserves of Chahkhatoon and Senjedeh in oxide zones are nearly finished and gold extractions will be continue from sulfide zones. Based on mineralogy and geochemistry studies, sulfide ores are very resisting because the recovered gold of these sulfide resisting ores is less than 80%. In the sulfide resisting deposits of Muteh, very fine gold is surrounded by Pyrite and Arsenopyrite. The common methods for extraction are not economical, therefore these resisting ore deposits should settle in a primary treatment, but the suggested methods are very expensive and the environment is polluted at a high level. In this paper, according to bioleaching advantage, this method was used for gold extraction from sulfide minerals. Thiobacilus Ferrooxidans is a proper microorganism in this method because gold grades from samples of Chahkhatoon and Senjedeh are less than 3 ppm. So, a norm sample was provided from Senjedeh and Chahkhatoon mines. Next, it was used in Stirred tank process. Their search showed that after 20 days of bioleaching process, M8 species with pH=2.2 are very important for the elimination of sulfide (%96.30).

in the present work, on the anticline of Gadvan (Gadaun) mountain that placed in northeast of shiraz, some investigation has done as preparation of lineaments map by Landsat 7 images, length, intersection, & counts density map of lineaments, calculate two geomorphic indices Smf & facet% and stereographic fold analysis which can use these items for structural analysis & morphotectonic  investigation. Geomorphic indices show active tectonics in this area so that the rate of uplift is higher than the rate of mountain front erosion, estimated 1 to 5 mm/year. Also automatic and semi-automatic methods are used with manual method to enhance lineaments. Map of length, counts & intersection density show the area of fractures anomaly and also can help in position determination of ground water boreholes in Dariyan plane. Kind and attitude are determined by stereographic fold analysis too.

Uncertainty in groundwater modeling mainly occurs as a result of input data error. After determination of aquifer parameters through inverse problem at the stage of model calibration and assurance about unique solution of answers in the processes of verification, it is possible to be confident about reliability of the model. Calibration is generally done with trial and error and automatic optimization. At the end stage of verification, this simulated flow model could be used for the prediction and optimization of groundwater resources. َAssemblages of planning, designing, or execution policies in various scenarios could be interpreted based on the assessment of simulated aquifer response. In this case study (Behbehan plain aquifer), the advantages and disadvantages of calibration methods have been assessed with the available computer codes.

A tremendous amount of rock is used in constructing shoreline protective structures on which the influence of marine environments is totally different from other areas. These materials must be classified according to particular size, shape and grading as specified by marine structure designers. Other properties of rock such as density are needed to be incorporated in design equations. Moreover, tough conditions prevailing marine environments cause the durability of rock to assume quite a peculiar and important stature. Durability is defined as the ability of rock to maintain its physical and mechanical properties for the period of time that it is present in an engineering structure. Hence, durability is a function of rock properties and the environment or conditions surrounding it.This study attempts to look further into rock materials of Pozm, Tis, Chabahar, Ramin, Briz, and Pasabandar’s breakwaters in the southeast of Iran from the view point of their durability and degradation in the armour layer. Also, it is aimed at setting forth appropriate criteria to quickly evaluate quality and durability of regional rock materials by considering samples of durable and indurable rocks of breakwaters, paying attention to field observations and durability evaluation engineering tests as well as introducing the most proper rock material deposits of the region.