JOURNAL OF EARTH AND RESOURCES
Year:2011 | Volume:4 | Issue:2 (11)|Papers Count:9

The available radioactive elements in the nature, in themselves decay series to other elements, emit alpha, beta and gamma rays that attention to power of penetration of gamma ray is used from this gamma ray measurements, for radiometric exploration of radiometric element specific for uranium. With use taken data of airborne radiometric simply can be studied a large area in a short time and with a little cost. In this study using satellite images, were obtained alteration. In the next stage of the geological and tectonic with radiometric data for overlapping were integrated into GIS database. Processing information and integrated layers were based on indicators overlap. Finally, potential areas of uranium mineralization were found for further exploration work.

Dalli Cu-Au deposit is located 40 km northwest of Delijan town in Markazi province. The 9 km2Dalli exploration licensed-area was identified at the end of 2005 using Landsat-TM satellite imagery data integrated with 1:100000 geological map of the region. Then, the identified area was subjected to other exploration stages such as prospecting and semi-detailed to detailed explorations. Dalli is the first economic Cu-Au deposit (with equivalent value), so far reported on Urumiyeh-Dokhtar Magmatic belt.  The prospecting stage study at the scale of 1:10000 was applied on the 9 km2of the Dalli licensed-area. The 1:10000 lithological-alteration map of Dalli was prepared using high resolution Aster Satellite imagery data and field work.  Then 21 rock samples were collected and analyzed for 44 elements by ICP and AAS methods in Australia. The analytical results showed that gold and copper grades varies from 0.24-2.04 ppm and 0.2-3.31 percent, respectively. At the end of the prospecting stage two mineralized zones of copper and gold was identified. The name of these two zones are South Hill (extending 180m by 160m) and North Hill (extending 300m by 200m). The mineralization at these two zones are associated with two quartz diorite porphyry bodies, potassic alteration and quartz-magnetite stock works.

The studied exploratory limits located in 1:100000 south of Langaroud geological map. This area includes parts of Gorgan- Rasht structural arena zone. After taking sample operation and samples analysis, statistical processing on data analysis had been done in order to keep the effect of lithology. The elements proliferation index quantities have been made. Also by the elements deviation processing, the elements abnormality and anomalous areas have been identified. In this phase, appropriate anomaly has been gained from Titanium and other 17 elements. Also geochemical anomalous controlled by taking sample from heavy minerals simultaneously. The recognized anomalous heavy mineral was ilmenite mineral that confirm exist of the Titanium. Geochemical analysis general results shows that the recognized anomalies mostly related to Titanium and rare soil elements and according to the exits of anomalous samples around fractures, the important rule of faults to make these anomalies, it has been accepted.

Hydro-geochemical samples investigation is the basic study in mining hydrology. Classifying of hydro-geochemical samples to homogeneous groups is the accurate tool to describe hydrogeological systems. Application of conventional graphical methods, such as the Piper diagram, Stiff diagram and Durov diagram for water samples classifying are efficient, when don't face mass of data. In the cases, the existence of large volume of data, statistical multivariate methods, such as principal component analysis, factor analysis and dendrogram plotting, are provided appropriate analysis by consideration required primary hypothesizes and imposing adequate precision. In this study, hydro-geochemical samples were provided from the various conditions and different mining regions (high to low water discharge) of Choghart mine. Analysis results included concentration of main cations and anions, pH, hardness and dry residual values for each sample that they were interpreted by using graphical methods (Piper diagram, Stiff diagram and Durov diagram) and statistical methods (clustering analysis,  principal component analysis and plotting dendrogram). Based on results of this research, ion's qualities of samples were consisted of chloride-sulfate anion and sodium-potassium cations. Finally, 2D distributions of related parameters were interpolated by ordinary kriging as geostatistical tools.

Creation of stable uniform walls is one of important operation in open pit mines. In Chadormalu Iron Ore Mine due to complex lithology and tectonic this problem is of great importance and to create stable uniform walls presplit blasting is utilized. In this method, at first presplit line and then the production holes are blasted that interaction of these are significant. Considering that presplit blasting should be done before its production block, presenting proper approaches for minimizing the impact resulted from blasting production blocks and back break in presplit line must be regarded a key task in stabilizing of walls. Blasting direction is a major factor which has a great effect in this matter. In this study is investigated the effect of blasting direction to creating secure walls using minimizing of blasting impact based on analyzing of monitoring data in Chadormalu iron ore mine.

Deposits of gold-copper Golouje is located 45 km north of Zanjan And 1.5 km west of copper abandoned mine Rasht Abad. This area is in the west Alborz–Azerbaijani zone and follow from magma and tectonic events. Veins are composed along faults, especially, The main fault Rasht Abad and Carat gold is noticeable in all samples of veins, Between 1-19 ppm. Also have shown a significant carat of the elements copper, lead and zinc. So according The deposits of gold Golouje is veins for determining storage was used Blocking technique because obtained nearest actual tonnage also storage extract open method, so the deposit volume was measured at several stages. First the volume and tonnage of deposits calculated according volume of veins and cutting zones without calculating the stone wall, After estimating storage can expect 871.087 tons Ore with average carat 3.34ppm and potential more than 2427 kilograms of gold. In the other stage, the volume of deposite calculate with average carat More than 1ppm and with calculating low-Carat parts between next veins. In this case deposite have 2237018 tons Ore with average carat 1.85ppm and potential more than 4081.71 kilograms of gold. And the final stage the volume of deposite is calculated with average carat More than 0.5ppm. In this case deposite have 3233453 tons Ore with average carat 1.35ppm is equivalent 4247.27 kilograms of gold.

In recent years, remote sensing technology has provided valuable information in the field of mineral exploration. Satellite data have been used widely in geology and exploration and to determine the location of mineral deposits. The remote sensing techniques, has been used significantly in the updating of geological maps, improved quality, and thematic mapping such as alteration zones maps, rock units, lineaments and fracture patterns, and has saved time and cost of in mineral potential mapping. This project was conducted in the Espeed iron ore deposit area with 13.87 km2 which is located in 60 km from the West Qom city, Iran. Studied area, in general, is composed of volcanic zones (mainly quartz andesitic- andesitic masses with volcanic ashes and pyroclastic materials, with some outcrops of acidic tuff dykes) and Tertiary sedimentary rocks. Mineralization occurred in the surface of quartz andesitic rock as disseminated of hematite and specularite mineralization. In Preliminary exploration operations conducted in this ore deposit, some trenches were dug in the altered zones associated with the faults that two trenches have been determined hematitic zone with 65-75% Fe2O3. After the stripping operation, has revealed a considerable extent of iron mineralization in the form of hematite. In this project, ASTER satellite images were used in different band combinations and LS-Fit (Linear Band Prediction), Matched Filtering, SAM (Spectral Angle Mapper) and band combination method for extraction iron oxide alteration zones. According to the results of field survey and the availability of an iron alteration zone-as an indicator- in the area, were provided an opportunity for assessing the accuracy, control and compare the results of remote sensing studies using these methods with field studies. Finally, among the investigated methods, 4.3.1 band combination method, was a most harmonious result with field studies to identify iron alteration zones in this exploration area.

Microscopic studies were conducted on polish, thin and thin polish sections prepared of samples from ore bearing veins. Chalcocite, nickeline, chalcopyrite, rammelsbergite and malachite were seen in polish sections that rammelsbergite were seen around the nickeline that represents deposit of nickel and increasing of arsenic in ore bearing solutions. In thin sections studies, Olivine, Plagioclase Feldspar, microlite minerals, carbonitization and silicification were seen that represents andesitic magma. double polish thin sections studies represent that Most of the fluid inclusions are of liquid riched two phase (L+V) type. Geneticly, primary types were selected for this study Based on freezing studies, calculated temperature of last melting point (Tlm) is from -1.6 to -18.5 celsius degrees that is equal to 2–22.5 % wt eq. Nacl. heating studies, have revealed a homogenization temperature (TH) range of 130–160 celsius degrees. Minerals array in polish sections, homogenization temperature–salinity binary plots, homogenization temperature–salinity binary plots associated control lines with stable density and homogenization temperature–density binary plots for calculate of pressure show that ore bearing fluids have at least two distinct sources that can represents at least two main periods of mineralization or two distinct ore bearing fluids origin. Probably one of them represents volcanogenic ore bearing fluid and another one represents basinal brine ore elements bearing solution.

Marjanabad lead-zinc deposits type is Mississippi valley deposit and it's located 27 km northeast of Manjil. Minerals has occurred in a dolomite- limestone in the upper part of Dorou formation. Upper of Doroud formations include light gray, cream and yellow limestone layer, In the end of the following Ruteh formation, layer was highly siliceousing, shearing, and is somewhat dolomitization, and in this zone ore mineral was formed. Mineralization location is a fault zone with a relatively steep slope which is about 2 to 3 m wide that mainly accumulated of carbonate of zinc and lead. Categorical storage of lead and zinc Marjanabad mines is 30075 tons.