نوع مقاله : مقاله پژوهشی
نویسندگان
1 بخش علوم زمین دانشگاه شیراز
2 عضو هیات علمی دانشگاه شیراز
3 شرکت اب منطقه ای فارس
4 شرکت مهندسین مشاور آبراه گستر تدبیر
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Jareh River has decreased in quality in some areas to the downstream. The purpose of this study was to evaluate the hydrogeological relationship between Ramghan salt dome and groundwater in the region. XRD analysis was performed on the cores extracted from 10 geotechnical boreholes. The results of XRD analysis indicate the absence of extensive salt layers in outcrop of salt diapir. Groundwater flow in the alluvial aquifer cannot play a major role providing salinity of downstream groundwater and the dissolutions of halite, as the main source of salinity of groundwater, may have occurred in other areas of the dome. Based on the results, the dissolution of evaporites, especially the halite within the Ramghan salt dome, is mainly responsible for increasing the salinity of groundwater and surface water in the study area. With regarding changes of the hydrochemical properties such as water type and salinity, surface water can be classified into four groups A to D. Group A is fresh water with EC values of 600-725 µS/cm, Group D is the accumulated brines on the surface with TDS values more than 300 g/l and the groups B and C are the result of relative mixing of those two groups. The groundwater level is above the river level and the groundwater flows towards the river. Jareh River is a gaining river and the base level of erosion of the study area and groundwater has mixed with surface water in several sections along the salt dome. Accordingly, the groundwater mixed with the river should be attributed to one or a combination of the three following origins: 1) River water that penetrates upstream into the ground, 2) Rainfall that penetrates and percolates to the aquifer through fractures and sinkholes, and 3) Groundwater of karst aquifers that flows to Jareh River through the underground conduits.
کلیدواژهها [English]
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