Evaluation of Sylhet sadar upazila's geological formation for groundwater availability

Abstract

There is sparse of hydrogeological data and insufficient knowledge in many areas of the country reliant on groundwater. Given the exponential expansion in groundwater consumption in recent years, it is imperative to comprehend how groundwater reservoirs respond to both natural and anthropogenic situations. Because of its extensive and unequal distribution, groundwater must be carefully studied in some locations to preserve this precious resource. This study was carried out to evaluate and assess the geological formation and some relevant parameters to enrich the geotechnical information of the study area for future use of groundwater. The soil samples used for the study were obtained from 8 SPT boreholes at 0 to 800 ft. depth at various work stations by percussion drilling method and all laboratory tests were conducted by BS 1377. Drilled soil sample with water was collected in a Polythene bag with a permanent marker pen at 20 ft. intervals of the drilling layer to perform a sieve analysis test.
Percentage fines decreased with an increase in boring depth and curves were closely packed homogeneity. The quantity of free silt and clay progressively reduced and coarsen materials were formed with the increase in boring depth. Results show that soil particle sizes increase with boring depth up to the upper surface of it. However, the area is suitable in terms of groundwater availability.