نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشکده مهندسی، دانشگاه قم، قم، ایران.
2 دانشکده زمین شناسی، دانشگاه تهران، تهران، ایران.
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Ali-Abad Plain of Qom Province, located in the center of Iran, is among the areas recently affected by the subsidence phenomenon due to water overexploitation. In this research, using the differential radar interferometry and Sentinel-1 images, vertical land deformation was monitored for 18 months from March 2015 to September 2016. The results showed maximum subsidence of 240 mm. Moreover, it was found that subsidence in this plain is a progressive and continuous phenomenon with an almost constant spatial distribution. Next, groundwater table fluctuations were measured in Saveh Plain for 14 years ranging from September 2002 to September 2016. The results showed a maximum water table decline of -44 m. Comparison of the ground deformation map with groundwater level fluctuation map revealed a direct relationship between spatial distribution and ground deformation intensity and groundwater drop. In addition, comparing the alluvium thickness variations with ground deformation indicates that the alluvium thickness of the Ali-Abad Plain varies from 20 m in its eastern part to 300 m in the western and central areas. The results do not show any significant relationship between these two parameters in the study area. Moreover, it was found that layering type and the presence of thick fine-grained formations are among other factors affecting the intensity and rate of subsidence in the plain. Regarding the direct relation between groundwater table fluctuations and subsidence rate in the study area, the water yield of the plain showed an annual deficit of 88.17 million cubic meters. Investigating the exploitation resources and the consumption type of groundwater resources in the study area showed that above 98% of the water extraction from the aquifer is through the wells, of which 92% is consumed for agricultural purposes. Hence, exploitation management of the wells, control of illegal exploitation, and revision of cultivation and irrigation are among the major strategies for restoration and balancing the groundwater resources in the study area.
کلیدواژهها [English]