JOURNAL OF EARTH AND RESOURCES
Year:2009 | Volume:1 | Issue:2|Papers Count:10

The increasing utilization of building stones has led to optimum and advanced exploration and exploitation methods of these stones. Iran is one of the countries that there are great potentials with regard to building stones. However, due to lack of informations and old excavation methods, production and export of these stones in Iran is not so high. The most important parameters that affect the design of building stones mine is determination of its geomechanical properties and geological structures. The study of joint sets is very important in order to design a building stone mine. Great unsafe issue such as the loss of life and money can arise by not studying the nature of joint sets. In other words by studying the nature of joint sets, this negative issue can be changed into a positive issue. In this research study, held investigations were carried at Divchal granite mine in Kelardasht. The investigation showed that there are three joint sets in the area from which the second joint set can be used to design the quarrying bench geometry in the mine. Finally the joint sets were used to design the mine benches especially for determining their heights and widths.

One of the most important characteristics in the reservoir studies is the determination of porosity. The amount of reservoir porosity represents the in-situ hydrocarbon whereas production rate is related to connectivity between pores. Porosity determination is done by different methods such as experiment on small samples in laboratory or in-situ determination using well logs. The difference between these ways is due to scale effect. Changing in sample volume has different results. So studying the scale effect is very important and was done by different methods. In this paper, we studied scale effect on porosity variable from an oil reservoir by geostatistic that is powerful in determine of anisotropy and data spatial variation. Also the anisotropy determined by semivariogram function that is representative dispersal of variables. Specifically, the behavior of the variance of the mean is used to investigate the definition of a representative elementary volume. To describe porosity, (or any other aquifer or reservoir parameter) it is useful to first define the concept of representative elementary volume. The representative elementary volume is a volume of reservoir over which the porosity, for example, is describable by a single value. This concept is necessary because a volume smaller than the volume that fits the definition of a representative elementary volume will yield different reservoir parameters depending upon where one places the representative elementary volume on the sample. According to this research the representative elementary volume for porosity was calculated for a gas reservoir. Also according to varigraphy results the reservoir is anisotropic.

The study of area is situated in Kerman (north east Baft) based of tectonically divisionsiffran this occurs in belt. Based in dimitryevig (1973) tectinig divisions on the dehaj - sarduieh belt of kerman region. The oldest units are composed if eocen volcano sedimentary complex which are intrusive bodices of probable oligo-miocen age and has occured mineralization and altratiin in the area. Hararan area the alteration more from kind argilhc silicic and propilitig. Which a ccompanies mineralization occurrence in surface are in cluding mala chit azurite chalcopyrite pirite hematite magnetite and limonites. By using of analysis preliminary of statistic calculation and geochemistry and distribution geochemistry map for mentioned element have been draw. the result show that highest anormal accumulation in this study their ranges investigated by name bajh –haji occurrence hararan occurrence and havij occurrence. According to know mineralization (gosan formation) in around of occurrence existence of silicic vine.Suitable alteration distribution variety of alteration and mean copper high grade sample surface (e.g.0.63). This occurrence can be taken hn the first step of next exploration including of geophysics exploration and semi - detailed exploration. Also the Hararan occurrence has been recommended for detail exploration. Presently the carrying out of exploration work on havij occurrence is not economic.

Bijegan Tappeh-Sorkh-e Barite Mine located at 21 Km southeast of Delijan and 4 Km from northwest of Bijegan Village in Markazi Province, and belongs to volcanic belt of Oroumieh-Dokhtar, is one of the most active volcanic belt. The nature of the host rock is igneous and its age is late Eocene-Early Oligocene? Ore body is nearly lenticular shape adjacent to Certaceous marl, along the fault, with dimensions of 50*15*6 meter and NE-SW trending. It is located between Eocene Volcanic and Lower Red Formation (LRF). Red color of the ore mineral is related to the Fe-hydroxide resulted from high level of fugacity of the environment.The morphology of mine area consists of three parts, Stockwerk of stringers, Massive Barite ore and Hematite red chert. The massive ore body including Barite, Hematite, Quartz, Malachite and Azurite.As a result of high level of barite compared with sulphide ores and wide extent of massive section compared with stockwerk and its simple structural region sorting, mine of Tappeh-Sorkh can be conformed to specifications of kuroko type of barite mine.

The Qezeljeh Kand strato–volcano (Quaternary age) is located in NE of Qorveh Town (Kaboudar–Ahang area) is the linear basaltic volcano in this area. The volcanic cone is polygenetic and is a mainly consist of basaltic lava. Scoria, ash and different kinds of volcanic bombs which covers Pliocene clastic sediments and quaternary travertine. This Volcanic cone was formed in an inter-continental environment in the post Pliocene.Xenoliths are observed both in lava and volcanic bombs, and can be divided in to two main groups: autoliths and real xenoliths. There are several Autoliths consisting of pyroxene, mica, amphibole, hornblende and apatite minerals, they have genetically relationship with lava minerals. Felsic xenoliths are mainly consisting of granite and gneiss and were detached from rock basement, during the eruption process, and they partly melted. The lack of volatile bearing minerals in some autolithe (such as pyroxenite autoliths) and abundance of these in another autolithes (such as apatite - hornblende autolithes), and periodical eruptions in the volcanic history, indicate a zonal magma chamber.On the other hand, abundance of hydrous minerals and absence of plagioclase in these autoliths proves the water saturation in depth of magma chamber which caused concentration of volatiles on the upper part of magma chamber resulting extremely violent eruptions.

Various volcanic rocks with Eocene ages outcrop in the southern of Deylaman. Based on of petrographic study these rocks mainly are made up of plagioclase, clinopyroxene and minor olivine and opaque mineral. Based on this study, these rocks are divided to three groups: basalts, andesi-basalts and dacites. Based on geochemistry data generally these rocks have calk alkali nature. Normalized trace element patterns in these rocks show enrichment in LREE and depletion in Ti, Nb, Zr and P. These characteristics are indicative of an arc subduction- related environment. Comparison composition of southern Deilaman volcanic rocks with word famous  basaltic rocks show that these studied volcanic rocks have geochemistry signature of arc rocks and were formed in a subduction zone. Subduction signatures of these rocks can be related to old ancient oceans in this area and so slab that it's melting produce these rocks melts can be resulted from subduction of this crust and or from a older crust in area. Based on overall data it seems that Southern Deilaman volcanic rocks are a part of volcanic arc that are related to these subduction zones and were formed in Eocene time.

Geophysical radiometric airborne data have high importance for radioactive mineral exploration. In fact these data is major base for uranium exploration. In this study by airborne radiometric data interpretation collected from Dehbakri 1:5 0,000 sheet No. 7548II situated in SE Iran expectation areas for uranium & Thorium were recognized. First, by statistical analysis of these data and drawing contour maps these areas were distinguished. Next, these areas were controlled in field by field geophysical operations, sample collection and analyzed and data accuracy was considered. Also, geological data were considered and comprised with geophysical airborne data. Finally by interpretation of drawn maps, expectation areas for uranium exploration in the sheet were introduced and proposed.

The region under study is located about 53 kilometers in the south of the Rasht, North West of the Ammarlu Mountains, and north of Iran. Due to the field studies and the data obtained from the study of geological maps of the area it was revealed that the Doulat Abad landslide is on old one. Under study one of the effective environmental factors for ancient landslide in the region under study is the Sefidrood River. Under study one of the effective environmental factors for Doulat Abad young landslide, have had the undeniable role with respect to the inherent conditions such as kind and tissue of material, uniformity direction water, slope, fault, hills shape, environmental factor. Three kinds of area were evaluated regarding the geology and engineering geology studies on the basis of suitable environmental and inherent factors. They include:1- area that don’t heavy any landslide and instability or there is little landslide in them2- area that have partial and are liable to landslide, and3- area that have the danger of instability and serious landslide. The results of studies include 2 engineering geology maps to the scale of 1:2000 and do rock mechanic examination that is presented with the solution for the stability of Doulat Abad landslide.