Topographic variation and its impact on groundwater depths in the Dafniya area of Misrata Municipality "A study using geospatial techniques"

Abstract

This study aims to analyze the spatial relationship between topographic variation and groundwater well depths in the Dafniya area of ​​Misrata Municipality, using Geographic Information Systems (GIS) techniques and spatial statistical methods. The problem of the study is to reveal the nature of the relationship between surface height and groundwater depth. The results showed a clear positive relationship; The coastal wells were shallower (8-32m), and the depths gradually increased towards the higher areas to the south, reaching 100m. Moran's index (0.1008) and Z-value (2.35) showed a weak tendency towards spatial clustering of well distribution in the study area, influenced by some terrestrial and agricultural factors. The Kriging and IDW spatial interpolation models proved to be very efficient in tracking water levels, while the TWI aquifer index provided an exploratory model of surface moisture. The study recommends reconstructing the GWR model by incorporating additional hydrogeological variables such as permeability and rock type, regulating well drilling, activating periodic monitoring to reduce depletion and salinization of the coastal aquifer, activating geographic information systems to monitor the aquifer, and relying on alternative sources such as desalination to prevent seawater intrusion and salinization of coastal wells.