Previous Year Question
The entire space between soil particles and fractures in rocks is filled with water. The upper boundary of this layer is called:
Correct Answer: C
Detailed Solution
The underground zone in which the pores of soil and fractures in rocks are completely filled with water is called the Zone of Saturation. The upper surface or boundary of this saturated zone is called the Water Table. The USGS likewise defines groundwater as water occurring in the saturated zone beneath the land surface and identifies the upper surface of this zone as the water table.
The depth of the water table is not the same everywhere. It may rise or fall due to factors such as rainfall, groundwater recharge, topography, geological conditions and groundwater withdrawal. Below the water table lies the saturated zone containing groundwater, whereas above it lies the unsaturated zone, where pore spaces may contain both air and water.