Iranian Journal of Earth Sciences
Volume:10 Issue: 2, Oct 2018

Groundwater is playing an important role in sustainability of irrigated agriculture in Pakistan by contributing about 40% in total water resources of the country. To ascertain the present status of the aquifer in the Upper Thal Doab area, a groundwater modeling using Visual MODFLOW 2011.1 has been executed. Steady-state model was calibrated for the year 1984 and transient state model was simulated up to predictive period of 2025. The transient simulation results indicate stability of the aquifer with minor difference between water flowing into and out of the aquifer. During 1984 to 2025 it has been observed that the total water inflows increased from 347.00 to 3029.14 BCM (Billion Cubic Meter) and total discharges from 347.00 to 3029.29 BCM, which shows stability of the total groundwater storages of the aquifer. However, if the pumpage increases with this rate, there are chances that groundwater of the area will deteriorate in future. This study provides a base for timely formation of management strategies for the reasonable utilization and management of groundwater resources in the area.

Mining operations and mineral-related industries are closely and directly related with the environment. The negative impacts of mining industry on the environment, known as environmental risks, must be controlled and managed in a way to minimize harmful and destructive effects. Environmental risk assessment studies are a suitable step to identify, analyze and rank the risk factors. In this study a hybrid model has been presented to identify the environmental risks caused by coal washing plant in eastern Alborz in the form of 17 risk factors and introducing 8 criteria to assess them. Then their impact has been studied upon 12 environmental factors such as agriculture, ecology and so forth. In this regard, the risks for each of the affected environmental components have been assessed using linear assignment method, which is one of the most important multi- attribute decision-making methods. The results showed that in components of "area usage", "social issues", "surface water" and "underground water", the risks of "exposition of the plant and the tailing area", "tailing discharge considerations", "type of geological formations of the area" and "changing the usage of the area" have been ranked first, respectively and have been introduced as the most critical risks for the above-mentioned components.

Thermal history and apatite fission-track ages were determined for the Kaleybar, Razgah and Bozqush alkaline intrusions which display Eocene-Oligocene stratigraphic age. These subduction-related intrusions are located in the Alborz-Azarbaijan magmatic belt which is characterized by a Paleogene magmatic flare-up associated with extensional/transtensional tectonism. The mean of Uranium content and apparent age for apatites of the Bozqush, Kaleybar, and Razgah were obtained 21.8 (±3.8), 9.5 (±5.7), and 24.5 (±11.3) ppm and 29 (±1.8), 36.6 (±3.0), and 40.7 (±1.3) Ma (σ), respectively, which represented the time that the rocks of intrusions were last at temperatures of 60 ˚C to 110 ˚C. The results indicate that the apatite apparent ages are in concord with the stratigraphic ages. The apatite fission track ages and track lengths distribution were combined to construct time-temperature history by inverse modeling, which represented the all samples resided in the partial annealing zone (PAZ) for a significant period of time. The apatite fission track analysis indicated relatively complex cooling history for the host rocks because of the magmatic activity, as it was occurred during Cenozoic in the Alborz-Azarbaijan magmatic belt. The time-temperature curves of the studied intrusions begun with a relatively rapid initial cooling and followed by long residence at the PAZ temperature (heating stage). The time-temperature paths indicate that the start of rapid recent cooling to the surface temperatures was occurred at 5 Myrs.

The geometric and kinematic analyzing of the anticlines and their relation with the large-scale structures are used to determine the structural evolution of the area. The Dorbadam anticline is located in the Kopet-Dagh structural zone, 45 km due north of Quchan and on the Razavi and North Khorasan provinces border. The field study and geometric analysis indicate that the Dorbadam anticline has two culminations with an en-echelon arrangement and different structural evolution. The NW culmination (DA.1) is analyzed as a fault propagation fold geometry, while the SE culmination is known as a simple folding. The axial trend of the Dorbadam anticline has been changed and shows harmonic and Horizontal inclined, 1C subclass of Ramsay's classification, close, asymmetrical over fold in DA.1 part; upright and horizontal, open and symmetrical upright fold in DA.2 part. Aspect ratio on the Dorbadam anticline is 0.64 and has a parabolic appearance. The joint study revealed the existence of five major joints in this area which are bedding and strike joints (tension and compression joints parallel to the axial fold) or dipping joints (tension joints). The systematic joints analyzing of Tirgan Formation with T-Tecto software determined that the trend of maximum stress in the Cretaceous was S07W. The paleo-stress direction determined S25W with axial plane analysis. The Analysis of large-scale faults indicated a change in the stress direction during the time and specified they are post-tectonic and the activity of faults occurred in some various stress systems. The joint study revealed the existence of five major joints in this area which are bedding and strike joints (tension and compression joints parallel to the axial fold) or dipping joints (tension joints). The systematic joints analyzing of Tirgan Formation with T-Tecto software determined that the trend of maximum stress in the Cretaceous was S07W. The paleo-stress direction determined S25W with axial plane analysis. The Analysis of large-scale faults indicated a change in the stress direction during the time and specified they are post-tectonic and the activity of faults occurred in some various stress systems.

The Chah-Shur clay deposit is located in150 km southeast of Isfahan. Eocene igneous rocks ‎and Quaternary deposits cover the area. Eocene volcanic rocks include andesite and tuffs ‎which relating to magmatic activities of Urumieh-Dokhtar magmatic belt. Alteration of the ‎vitric and lithic tuff units has produced the clay deposit. Based on the petrographic studies, ‎the main minerals in tuff units are plagioclase, K-feldspar and quartz. The major phases in ‎clay deposit are kaolinite, illite, montmorillonite, quartz, albite and orthoclase. Also, ‎muscovite, chlorite and hematite are as minor phases. The mineralogical studies show an ‎intermediate alteration. The clay deposits can be formed by supergene or hypogene ‎processes; while the combination of both of them can result in the formation of mixed type ‎clay. The geochemical data of Chah-Shur clay deposit show scattering between hypogene ‎and supergene type genesis. The abundance of Fe2O3+TiO2 vs Cr+Nb and Zr vs TiO2, as ‎well as Sr+Ba vs Ce+Y+La suggest mixed and hypogene type. On the other hand, P2O5 and ‎SO3 plot shows the mixed type and supergene genesis. The results obtained from ‎mineralogical and geochemical studies indicate that the genesis of the Chah-Shur clay ‎deposit can be considered mixed type.‎

In the present research Kuh-e Siah Sections in the Northeast of Shiraz in the Interior Fars, was investigated to study microfacies, sequence stratigraphy, facies analysis and sedimentary environment of Fahliyan Formation. Generally, 345 meters of these sediments were studied by investigating 240 thin sections. In this study, the indicator microfacies were accurately identified which include Mudstone, Wackestone, Packstone and Grainstone. Besides, skeletal and non-skeletal grains of these microfacies are Intraclast, Bioclast, Exteraclast and Pelt. According to lithostratigraphic study, underneath limit of Fahliyan Formation with the Surmeh Formation and its upper contact with Gadvan Formation were in the gradual form (SB2) and included (TST-LST-Early HST-Late HST) system tracts. In general, there were two second-degree sequences in this section., According to the analysis of the sedimentary environment, the The lowermost of the Fahliyan Formaion is comprised of the Inner shelf deposit Which changes to Open marine sediments (with homoclinal type) And eventually terminates to outer shelf deposit.. Based on the received micropaleontologic data, the age determination of the Fahliyan Formation Is assigned to Neocomian.

The Gurpi Formation constitutes the source rock for petroleum in the oil-rich South Iranian Basin.Gurpi Formations is well distributed along Zagros Foreland Basin particularly in the north west of the Zagros (Lorestan Province). For Microbiostratigraphy and Paleobathymetric studies of the Gurpi Formation in the central part of Lorestan two stratigraphic sections including Sultan and Amiran sections were selected. In this study, 48 foraminiferal species belonging to 25 genera were identified, and 7 biozones were recognized; Globotruncanita elevata Zone, Globotruncana ventricosa Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Globotruncana aegyptiaca Zone, Gansserina gansseri Zone, Contusotruncana contusa Zone.Planktonic foraminiferal morphology was studied in order to assign paleobathymetry and the changes through sedimentation course of the Gurpi Formation.Three third-order sequences were identified,on the basis of deepening and shallowing patterns in the morphological changes and the distribution of the Gurpi Formation planktonic foraminifers and planktonic/ benthic ratio.

Most conventional statistical methods aiming at defining geochemical concentration thresholds for separating anomalies from background have limited effectiveness in areas with complex geological settings and variable lithology. In this paper, median+2MAD as a method of exploratory data analysis (EDA) and concentration-area (C-A) fractal model as two effective approaches in separation geochemical anomalies, are used to identify geochemical anomalies in the Takab 1:25000 geochemical data sheet by using stream sediment geochemical data and lithogeochemical samples. We compared the anomalous area created using thresholds from various methods on the same data against known deposits and lithogeochemical samples. Results indicated that EDA methods are more impressible by lithology and could not well identify the geochemical anomalies in the areas with variable lithology. On the other hand, the C-A model based on the distinct anisotropic scaling properties, was better in revealing local geochemical anomalies, because it considered the spatial characteristics of geochemical variables.