مجله یافته های نوین زمین شناسی کاربردی
پیاپی 29 (بهار و تابستان 1400)

This paper show the importance of trace elements in the estimation of Au and Ag. To predict Au and Ag, the selection of finder elements was performed using multivariate statistical analysis of factor analysis and cluster analysis and linear and nonlinear regression models. In this research, it were studied 35 elements in 108 samples using statistical software Statistica 10, for forecasting and estimating the best finder elements for Au and Ag. Data were controlled based on statistical methods including identifying out-of-order elements, normalization and data standardized. Based on factor analysis and cluster analysis, the elements of the same group with Au and Ag include, Pb, Sb, As, Cd, and Zn, which can act as a finder element of Au and Ag. The purpose of the multiple regression method is to find the logical relationship between Au, Ag and finder elements. In this study, it is considered Au and Ag as dependent variables and Zn, As, Cd, Pb and Sb as independent variables. The correlation matrix shows that the correlation of Au with Zn, As, Cd and Sb is higher than 0.70 and Pb is less than 0.70. Therefore, based on linear and nonlinear regression models, Fisher test, Student t test and probability level showed that the elements of Cd, As and Sb are suitable for prediction of Au and As, Cd, Pb and Sb for prediction of Ag. In addition, non-linear regression model was found to be more suitable for prediction.

Freshwater is a vulnerable, limited, and vital resource. Today, the increasing global population and declining water resources are one of the most important challenges facing mankind. Water resources can directly affect socio-economic growth and development, they can serve as the foundation for development activities.One of the most important issues of the current century is the issue of global warming, which is exacerbated by the impact of greenhouse gases and is expected to cause changes in climate variables. The purpose of this study was to investigate the changes in surface water flow and groundwater level in the Razavachai plain of West Azarbaijan province. Accordingly, IHACRES runoff rainfall model and artificial neural network were used. For this purpose, precipitation data, mean temperature, surface water flow of Rozhay-Chai River and groundwater level of the region were used. In the present study, using the ACCESS1_0 model, the fifth report under climate scenarios 4.5 and 8.5, temperature and precipitation variations in two periods (2020–2052), (2053–2085) were investigated. The results showed that in the region the temperature changes under RCP8.5 scenario were higher than the RCP4.5 scenario and the precipitation decreased in the expected months. The rainfall-runoff model performed better in predicting the flow of the Rozhachai River in the base period than in the next period and showed a correlation coefficient greater than 0.5. The model performed better in baseline prediction of groundwater level with artificial neural network. Finally, in the distant future, the effects of greenhouse gases have a stronger signal and increase temperatures and reduce precipitation.

Nosud water transfer tunnel with a length of 45 km has been constructed to guide and transfer water in the northwest of Kermanshah. The tunnel passes through several anticlines and synclines and as soon as its axis enters the Garo and Gurpi formations, gases with a volume of more than 400 ppm are drained into the tunnel, which is mainly related to the Azgleh and Kurdish Qasman anticlines. In the Zagros Basin, the Garou and Gurpi Formations are known as high potential oil source rocks. In the study area, despite the predominant type III kerogen, which is mainly of dry origin, a large volume of gases, mainly methane and carbon dioxide, are found. Due to the expansion of Garo and Gurpi formations in the region, gas-prone zones in the tunnel axis are divided into four parts A, B, C, D, which is the largest volume of gas produced in the Kurdish anticline of Qasman and is related to zone D. The gases produced from these areas along with a large volume of water are led into the tunnel through tectonic fractures, which are mainly joints and faults, among which faults play a very important role in the Kurdish anticline of Qasman and the anticline of the herd.

The phosphorites horizon related to the Jeirud area is located in the central part of the Jeirud Formation, in the northern Tehran. The Late Devonian sediments of this formation is composed mainly of detrital rocks such as sandstone, sandy shale and sandy limestones. Phosphorite mineralization is mainly concentrated in the sandy shale horizon. Optical microscopy and X-ray diffraction (XRD) results showed that fluoroapatite is the main phosphate mineral and other gangues minerals composed of quartz, calcite, pyrite, iron oxides (mostly goethite) and clay minerals. The X-Ray Probe Micro Analysis (XPMA) results showed that fluoroapatite is the main host mineral for REEs. Other REE-bearing minerals include monazite and very rarely zircon. The Ce concentration (as representative of REEs) is highly variable in the decomposed apatite grains and the amount of Ce and other REEs in sedimentary apatite originating from primary rare earth elements. The concentration of REE in this phosphorites are related to the deposition environment, duration of seawater interaction during and after apatite formation, chemical composition of pore-water, organic source, apatite crystal network and the effect of the allogenic events.

Sandstone outcrops of the Qom formation extend to a large part of northern Hamedan. This rocks are used as construction materials in Hamedan city. In this research, in order to identify the characteristics and engineering behavior of the sandstones, 15 rock blocks from Latgah (northern Hamedan) were selected. Lithological characteristics, physical and mechanical properties of these sandstones are determined. The samples were tested under the Schmidt hammer hardness test, durability, point load strength index, uniaxial compressive strength, Brazilian tensile strength and longitudinal wave velocity. The results of this study showed that the differences in the lithological and physical properties of sandstones have led to change in their mechanical properties. The relationship between physical and mechanical properties of sandstone has determined by regression analysis. Based on the obtained results, the mentioned rocks are suitable for use as Malone stone and building stone. The highest correlation between the uniaxial compressive strength (UCS) test with longitudinal wave velocity in dry and saturated state, were obtained that the determination coefficient (R2) are 0.93 and 0.91, respectively.

For investigating the paleoecology of the Sachun Formation in the Interior Fars Zone, Dariyan and Kuhenjan sections in the east of Shiraz and around Maharlu Lake have been selected. The deposits of the Sachun Formation in this area are generally composed of limestones and sandy limestones. The Sachun Formation overlies Pabdeh Formation in both sections and is overlain by deposits of Jahrum Formation conformably. Biostratigraphic data based on benthic and planktic foraminfera and calcareous algae indicate Lower Paleocene to Lower Eocene age for the respected sequence. The abundance have a specific range size of different of foraminifers species using Miliolids and Rotalids on these unstable conditions and lack of calcareous algae and foraminifers such as Orbitolites sp. Lithophyllum sp. is used in this area to raise shore in the Qorban Member, followed by the study of eutrophic conditions in the middle and lower Sachun Formation. Facies and biostratigraphic evidence indicate that depositional environments of the Sachun Formation was deeper in the study area than the type section in southern Fars zone.

Electrical conductivity increases in groundwater around the gypsum mines because of ions dissolution. this is a useful indicator in gypsum mines exploration, but not enough to that aim, so the elements with high concentrations involved in increasing EC should be identified. This study aims to investigate the efficiency of ANFIS-FCM method to exploration of salty gypsum mines using hydrogeochemical changes of groundwater, which was tested on a case: Anar salty gypsum mine. to this aim, 21 water samples were taken from wells across the plain and chemical analysis of samples was performed in the laboratory. Then, the resulted data were statistically analyzed and descriptive statistics of the data and correlation matrix of the studied parameters were obtained using SPSS software. Forming a data correlation matrix, it was found that in samples near the salty gypsum mine, some ions had the highest correlation with electrical conductivity (EC) including sodium, magnesium, calcium, manganese, selenium and lead, while the mentioned parameters had the highest correlation. The 6 mentioned elements selected as the model inputs and the electrical conductivity was the output according to purpose of the current research. After standardization, the data were entered into MATLAB and the electrical conductivity was predicted using ANFIS-FCM method. The measured electrical conductivity was used directly to compare with the electrical conductivity of the intelligent method. Based on the model results, the estimated electrical conductivity in the study area had very good accuracy and high correlation with the measured values. As a result, ANFIS-FCM intelligent method is an effective method to diagnose the salty gypsum mine. If this method is used in groundwater around other salty gypsum mines in Iran and a similar result be observed, its efficiency in diagnosing the salty gypsum mines is confirmed.

Zuzan region is located 80 km southeast of Torbat Heydariyeh city (northeast of Iran). This area is located in the northern part of the Lut block and the oldest rocks in the area include Staurolite schist’s, Garant Muscovite Shist and Transformed Limestones belonging to the Paleozoic, the main rocks of the region, deep and semi-deep penetrating masses in Diorite, Andesite, Andesite Porphyritic, Monzonite, granodiorite, belongs to the Paleocene. In the penetrating masses of the area, large and different alteration zones can be seen. Ultrasonic zoning in the area includes porphyry alteration, argillic, quartz seresite, pyrite and getting Skarn and a combination of these. Based on the combination of mineral cognition and high magnetic acceptability (on average about SI 5-10 × 500), the permeable masses of the region belong to the magnetite series (oxidant type) and are of type I granites. The presence of extensive and suitable alteration systems, the presence of semi-deep masses such as Monzonite masses, Monzonite quartz, Diorite and Diorite quartz, the general tectonic and geological pattern and the Magma series west of Zouzan confirm the exploratory potential for the porphyry system in the area, also study used fractal-grade methods - number in the range for the elements gold, copper, silver, lead and zinc to identify and identify multiple statistical communities for each of these elements in the Zouzan range. The aim of this study was to investigate the genesis and origin of mineralization and fluid studies involved in Zouzen region, to do this, three samples of calcite particles were found in volcanics in the area. After preparing two-polished sections in the Mining Laboratory of Iran's Mineral Processing Research Center, Were studied. Based on the results of these studies, it can be stated that the fluids are formed in low pressure environments (50-100 bar and low salinity (0-5% wt.) and have a low density of (0.7 to 1 gr / Cm3), also to determine the origin of fluid intermediates, the diagram of the homogenization temperature against salinity was used, These studies have determined the origin of these intermediates as fluids with a source of metamorphosis and atmosphericity. It is possible to pay attention to the conditions of the deposit as well as the low salinity rate and the average homogeneity temperature of these mediums. According to all the above information about the Zouzan deposit, considered the deposit to be part of the margins of a porphyry mass, Due to the infiltration of apophyses from the main mass, it has caused mineralization and also the phenomenon of Skarn in the vicinity of limestone in the study area.

Rocks in cold environments are usually exposed to freezing and thawing conditions. The freeze–thaw process is one of the most important and intense physical weathering processes that affects the physical and mechanical properties of rocks by reducing the durability and stability of rocks. In this study, the effect of freezing temperature in a freeze–thaw cycle with three freezing temperatures of -20, -40, -60 on permeability, tensile strength, uniaxial compressive strength, modulus of elasticity, triaxial compressive strength at confining pressures 3, 5 and 7 MPa, cohesive and internal friction angle of sandstone samples of Lalon formation in Lushan region was investigated and the effects of freezing temperature on the mentioned properties were studied and compared with the properties of samples that did not undergo the freeze–thaw cycle. The results showed that with decreasing freezing temperature in a freeze–thaw cycle, tensile strength, uniaxial compressive strength, triaxial compressive strength, cohesive and modulus of elasticity decrease and permeability increases.

Magnetic anomalies before an earthquake occurrence have long been discussed as precursors to seismic activity. In this study, by repeatedly over-plotting magnetic data related to each day (24 hours) in the same frame, for different components (Z, Y, X) or (Z, D, H) of three geomagnetic stations in Japan (MMB, KAK, KNY) over a period of one year, the characteristic curve of the geomagnetic stations are extracted. The purpose of this method is to try to reduce the effect of diurnal variations in the magnetic field from geomagnetic records and its use led to a more significant differentiation of the anomalies observed before the earthquake compared to the original data. Although previous studies have shown that geomagnetic data can be used as a precursor of earthquakes, the presence of magnetic storms in the study period led to the conclusion that commenting on the relationship between the observed anomalies and the earthquake requires more data and investigations.

In the present study, a stratigraphic section was selected on the Poshte-Jangal anticline in the southwestern part of Khorramabad to study the microbiostratigraphy of the Cretaceous sediments. This Section with a thickness 190 meters consists of invariable thin to Medium bedded limestones with Middle Turonian to Late Santonian age which were deposited in a continues sedimentation process. Both lower and the upper boundaries of this formation with The Surgah and Gurpi formations are conformable, respectively. In the present study of the Ilam Formation, 12 genera, 40 species and 4 biozones of the planktonic foraminifera were recognized. Based on the stratigraphic distribution of the introduced species and identified biozones the Middle Turonian to Late Santonian age is suggested for deposits of the Ilam Formation in this stratigraphic section.

Photogrametry with UAV (unmanned aerial vehicle) is a fast, accurate and cost-effective approach to obtain high-resolution spatial information. Taking overlapped photos of the target, production of 3-D dense point cloud, digital elevation model and orthomosaic from the region surface as well as verifying their accuracy using a definite number of ground control points, are main stages of the process. In the present research, photogrametry through UAV was used for monitoring, modeling and evaluation of exploited and residual ore reserve of Qods sand and gravel mine in Lanjan district of Isfahan. Based on dimensions and form of the region, nine flight lines with approximately 37m interspacing and 114m flight altitude were designed and traversed. The total number of photos taken from the region is 225 with 75% and 65% longitudinal and transverse coverage for the images, respectively. The number of six control points (five control points and one check point) were also scattered at the region so that the error range from -1.5 to 1.5mm with the total error of about 6.8mm is the appropriate precision. Total accuracy of the survey operation using the UAV was validated through comparing with ground check point via accurate three frequency GPS. The survey errors in the three coordinate directions are negligible, less than 5cm. At the end, the volume of exploited part and residual deposit was determined and with multiplying by average density (1.4 gr/cm3), the amount of extracted and residual ore reserve was calculated 3657.43 and 82942.55 tones, respectively.