GL102 Lecture Notes - Lecture 16: Non-Renewable Resource, Geyserite, Subsidence
Document Summary
Groundwater: water is pores of soil and sediment, plus narrow fractures in bedrock. Largest reservoir of fresh water readily available to humans. Belt of soil moisture: water held by molecular attraction on soil particles near the surface. Zone of saturation: phreatic zone, water percolates downward, zone where all open spaces are completely filled with water: groundwater. Water table: upper limit of zone of saturation, shape is usually a subdued replica of the surface topography. Capillary fringe: extends upward from water table by surface tension in pore spaces between grains of sediment. Zone of aeration: also called vadose zone, area above water table, capillary fringe & belt of soil moisture, water cannot be pumped by wells. Water table helps to predict productivity of wells. Depth to water table is highly variable; vary seasonally and year to year. Water level of wells coincides with water table. Mapping shows that the water table is usually a subdued replica of the surface topography.
