Kelale mountainous region is located in the east of the Golestan province. There are several karstic springs such as Zav، Aghsoo، Yal-cheshme in the region due to the existing karstic limestone and relatively high average precipitation value. The development of karstic formation in Kelale area and catchment area of four major springs has been investigated in this study based on geology، hydrogeologic and hydrochemical factors. In this area، springs are discharged from Lar، Tirgan، and Mozduran karstic formations and Sarcheshmeh shale formation. Different karst features such as closed depression، sinkhole، joint and fractures were observed in Lar formation during field investigation، then the Lar formation proposed as catchment area. The types of flow in all springs are conduit and diffuse flow. Zav and upper Yal-cheshme with three recession coefficient، are fed by a well-developed karstic aquifer; while the recession curve of Aghsoo and lower Yal-cheshme have one recession coefficient، indicating weaker karstic development in the basin. All the springs have the same origin and mainly have Ca-HCO3 water type. Cation exchange also affects the hydrochemical characteristic of the springs. All springs are super-saturated with calcite and dolomite but under-saturated with gypsum and halite.

Rudbar Lorestan Dam and Power Plant locates on the High Zagros structural zone, according to the geological map of Iran. The Dalan Formation, Permian age, forms the geological structure of dam body foundation and a portion of its reservoir. Meanwhile, outcrops of an Upper Cretaceous formation, called Sarvak Formation, are exposed out beside the Dalan Formation, due to effect of thrust faults. The main sources of Rudbar Lorestan river are precipitation and drainage of groundwater. The karstification process in carbonate sediments at the site was expected to be expanded well, due to geological and climate conditions. However, based on the evidences of karstic features, which could make a drainage network, have not seen. Both confined and unconfined aquifers present in the site. In this regard, presence of artesian boreholes is a good evidence for confined aquifer. The dominant types of ground water are calcic bicarbonate and sulfate, based on chemical analysis of 22 samples, collected from six sources of water at the site, In this manner, the types of water of the Rudbar river, Kish spring and outlet of access tunnel T2 are calcic bicarbonate, because of recharge from unconfined aquifers and short residence time. However, the type of water of artesian boreholes, i.e. TG-4 and RB-8, and inlet of the access tunnel T2, are calcic sulfate, based on contact of water with sulfate minerals and long residence time in confined aquifers.

Determining the groundwater flow direction in karts terrains is very important to understand the hydrogeological conditions. Saldoran Anticline is located in Chahar-Mahal and Bakhtyari province. The presence of highly karstified limestone and the relatively high mean annual rainfall in this region lead to the evolution of major karst springs such as Sarab-Baba heydar, Bagh-Rostam and Pir-e-Ghar. Studying the physical and chemical features of these springs together with determining the ground water flow direction are vital to characterize Saldoran karstic aquifer. The rate of mean annual precipitation is higher than 600 mm which occurs dominantly in the form of snow. The mean discharge and EC values are 1. 9 and 438 in Pir-e-Ghar, 3 and 475 in Bagh-Rostam and 0. 98 m3/s and 347 μ mhos/cm in Sarab-e-Baba Heydar springs, respectively. Two different recession coefficients (α 1 (0. 002) and α 2 (0. 003) ) were recognized from the recession curves of the springs. The α 1 regimen takes about 4 months, during which the major conduits discharge the infiltrating snow melt water. The α 2 regimen which represents the discharge through the narrow fractures and joints (diffuse flow) continues for about 2 months. There is an inverse relation between discharge and EC values. The highly variable values indicate high degrees of karstification. The main flow directions in Saldoran anticline was estimated from north west to south east according to the hydrogeological and geomorphological parameters such as karst valley, sinkhole, fault, fracture, dip and elevation.

Introduction: About 1/4th of the world deserts is covered with Aeolian sand (McKee, 1979; Ghadiry et al., 2012). Sand dunes are considered as one of the most important geomorphic features of such environments the formation of which shows the abundant resources of sand, the sand-moving powerful wind and the suitable conditions for sediment deposit (Tsoar, 2001; Michel et al, 2018). The most significant feature of these landforms is their dynamics (Maghsoudi et al, 2017) and The dimensions of these landforms is a function of parameters like sand origin, wind power, wind aspect, the amount of particles carried and time (Ahmadi, 2008). Considering the controlling elements of sand dunes, the depth of groundwater and surface moisture are determining elements in specifying the amount of portable deposits and the formation of sand dunes (Hesp, 2000; Bauer et al, 2009; Poortinga et al, 2015; Silva et al, 2018). As a matter of fact, the high water tables limit the movement of sands (Arens, 1996; Oblinger and Anthony, 2008). Materials and methods: In the first stage, two neighboring sites covered by sand dunes were selected based on Google Earth satellite images and field observations. In the second stage, after georeferencing aerial photos taken in 1967 and the satellite images taken in 2017, the rate of sand dune movements was determined and using Transec tool their movement rate with a distance of 1 meter was calculated by GIS software. In each site, regarding the location of the sand dunes and transects, four borings were located for drilling in a field operation and the status and height of the borings was determined by GPS. After the collection of sediment samples, each sample was completely mixed and 100 grams of each sample was taken for chemical analyses. After moving from the depth of groundwater, the depth of the water was measured by a tape measure in each bore. Then, 100 millimeters of water was collected by a water sample collector device for doing experiment. In the geomorphology laboratory, initially the amounts of TDS, EC, and pH in the sample waters were measured by a multi parameter device, version HI9811-5. To measure the amounts of TDS, EC and pH in sediment samples, saturated paste method was utilized. Here, the samples were initially dried in a drying device, and then 50 grams of each sample was measured with an accurate scale and mixed with 50 millimeters of distilled water. In the following step, the distilled water was mixed with sediment samples and the amounts of EC and TDS was measured using the multi parameter device and other devices. Results and discussion: The analyses results of sand dune movement in case study indicate average, minimum and maximum of sand dunes movement are respectively 22. 91 m, 0. 11 m, 51. 24 m in the first site and 11. 74 m, 0. 01 m, 41. 6 m in the second site within 50 years. The result also indicate average of sand dune movement rate in site 1 (0. 45 m in year) with Haloxylon vegetation is nearly double of site 2 (0. 23 m in year) which haven’ t any vegetation. The results of examinations on the qualitative nad quantitative features of the groundwater indicated that the average of ground water depth, TDS, and EC are respectively 1. 25 m, 8595 ppm, 17280 µ S/cm in the first site and 0. 71m, 12990 ppm, and 26160 µ S/cmin the second site. The finding of sample sediment analyses shows that the lowest degree of salinity belongs to the sediments of 80-100 depth in the first bore Of the first site with an amount of 840 ppm and 1820 µ S/cm and the highest 11900 ppm and 23870 µ S/cm belongs to the depth of 0-20 in the bore 2 of the second site. Conclusion: The obtained results indicate that the relative difference in sand dune movements of the two neighboring sites is caused by the hydrologic conditions of the area. In other words, the quantity and quality of groundwater have influenced the rate of sand dune movements in two different ways. In the first site, the existence of groundwater with a lower salinity has resulted in the formation of vegetation and reduced the speed of sand dune movements. However, in the second site high water tables, high Capillary action power, and high salinity have led to a lower rate of sand dune movements compared to that of the first site.

Faults are among very important factors that makes the groundwater flow systems complicated. Doroud Fault in Doroud-Borujerd plain, as a segment of the main Zagros thrust, is an active and strike-slip fault with NW-SE trend. The aim of this study was to evaluate the Doroud Fault impact on alluvium aquifer after the earthquake event of March 2006 using the groundwater iso-potential map, hydrographs of observation wells, electrical conductivity of the groundwater, and the water table fluctuations in relation to the earthquake. Results showed that the abrupt changes in the lithology and thickness of the aquifer as well as the groundwater salinity areprobably associated with Doroud Fault’s movement. In addition, lagoonal fine grained sediments and the low quality of groundwater observed in the eastern fault block and moreover, the groundwater channelized in the western block of the fault are among the hydrogeological effects of this fault. This study suggests that in one month the earthquake caused up to an approximate two meter rise in water table in the areas adjacent to the fault comparing to 0.5 meter water table rise in other areas. Unexpectedly, the electrical conductivity of groundwater has a decreasing trend in the flow line direction, but with some local increasing anomalies along the fault zone.

One of the main challenges facing the sustainable development of the Kalaleh region is the need for better management of this limited karstic fresh water resources. Kalaleh mountainous region in the north of Iran is drained by several karstic springs such as Zaw, Aghsoo and Yal-cheshme, having discharge rate of 20 to 2500 lit/s. The springs are mainly discharged from Lar, Tirgan, Mozduran karstic formations. In this research, the potential recharge mapping and catchment area of the major karstic springs have been investigated based on the groundwater balance and a GIS approach considering geological factors. In another part of the study, the determined primary catchment area by hydrogeological budget method was reconfirmed with geological method and the results were acceptable. Eight potential recharge contributing factors were evaluated using the GIS including drainage and slope, karstic features, lithology, land cover, precipitation and lineaments. The weights and the score of the factors were assigned based on aerial photos, geological maps, land use database and field verification. The different prepared layers were overlaid in GIS environment, and finally, the mean annual recharge rate of the karstic springs was determined which are in the range of 39-44% of the precipitation. Understanding the groundwater potential recharge zone of the Kalaleh watershed is important for management, proper utilization and future planning of water resources for sustainable management. The Lar formation has higher potential for karst development and infiltration than others. The spring’, s discharge rates have also confirmed these results. The effective karstic formations in recharging process in order of significance are Lar, Mozduran and Tirgan.

Karstic aquifer is one of the important groundwater resources in Kermanshah Province. The aim of this study is investigation the role of development in karst aquifer in hydrological characteristics of karst springs. The study area in this research includes two karstic aquifers include Bistoon-Parau and Patagh mountain in Kermanshah Province. In the Bistoon-Parau region, we used Bistoon, Berkeh and Gaznahleh springs data and Patag h region of Ghareh Bolagh Spring data. In this study, we used monthly precipitation and springs discharge during 20 years. To determinate the development or undevelopment of karstic aquifer, re cession coefficient, storage volume dynamics and catchment area were calculated for each springs. The results of calculation of dynamic storage volume showed that the Gharebolagh Springs in Patagh region has dynamic storage volume equal 29.3 Million cubic meters more than Bistoon, Berkeh and Gaznahleh springs in Bistoon-Parau region with dynamic storage volume equal 0.55, 2.2 and 1.3 Million cubic meters, respectively. So, these results showed more development of the Bistoon-Parau than Patagh region. Based on the results responses of the hydrological model Bistoon-Parav as a developed karst aquifer more quickly and severe than is Patagh area.

Physicochemical and isotopic parameters of springs are one of the important parameters in hydrogeological studies, because they represent the primary characteristics of precipitation and the history that groundwater flow in the karst. In order to investigate the flow system in the karst of Jahrom-Asmari formation in the area of Sangvil anticline in Chaharmahal & Bakhtiari provience, discharge, hydrochemical and environmental isotope data of springs, boreholes, precipitation and river were studied and it was determined that the karst flow type of the range is mainly dependent on the joint and fracture and the flow type in the range is diffuse-conduit and diffuse. Since the use of isotope studies in completing hydrogeological studies and detection the type of flow is useful, along with other parameters, Based on the studies carried out in this research, the Meteoric water line in the Sangvil anticline was obtained as the relationship = 6.3 δ18O + 14.8 δD with a correlation of 96%.The average amount of oxygen 18 in meteoric water and water resources is equal to -4.56 and -7.06 permil, respectively, and the average amount of deuterium in meteoric water and water resources is equal to -13.82 and -32.06 permil, respectively. in the present study, the study of environmental isotopes showed that the anticline aquifer has negative values compared to the local meteoric water line, and high volume precipitation and recharge snow determines the isotopic composition of the anticline aquifer. In this way, precipitations with low volume and high isotope composition penetrate less into the aquifer.