Movement & Storage of Groundwater Section 10.1 Movement & Storage of Groundwater

Warm Up Look up the definitions and use in a sentence for: Topography Porosity Runoff Saturation Permeability

The Hydrosphere The water on and in Earth’s crust makes up the hydrosphere. About 97% of the hydrosphere is contained in the oceans. The other 3% of the hydrosphere is freshwater. More than 90% of Earth’s freshwater is in polar ice caps and glaciers. Most of the remaining 10% is groundwater.

Runoff The ultimate source of all water on land is the oceans. Most of the precipitation that falls on land enters the ground through the process of infiltration and becomes groundwater. Only a small portion of precipitation becomes runoff and is returned directly to the ocean through streams and rivers.

Groundwater Storage The percentage of pore space in a material is called its porosity.

The Zone of Saturation What is the zone of saturation? The depth below Earth’s surface at which groundwater completely fills all the pores of a material What is the water table? The upper boundary of the zone of saturation

The Zone of Saturation Label the diagram below using Figure 10-2 as your guide. Soil moisture Zone of aeration Water table Zone of Saturation

The Zone of Saturation What are the 2 classifications of water in the zone of saturation? Define them. Gravitational Water: water that trickles downward as a result of gravity Capillary Water: water that is drawn upward from the water table

The Zone of Saturation The water table follows the topography of the land above it. The water table fluctuates with seasonal and other weather conditions because of its dependence on precipitation.

Groundwater Movement How does groundwater flow? What is permeability? Downhill in the direction of the slope of the water table What is permeability? The ability of a material to let water pass through it

Groundwater Movement How is the permeability in materials with coarse and fine grains different? Coarse (large) grains: high permeability (ex: sand & gravel) Fine grains: low permeabilities (ex: silt & clay) What does the velocity of groundwater flow primarily depend upon? The slope of the water table (the steeper the slope, the faster the water flow) Permeability of the soil

What is the major factor that determines velocity of groundwater? Groundwater Movement What is the major factor that determines velocity of groundwater? Permeability Regardless of slope, velocities through permeable materials are always higher than velocities through impermeable materials

What are aquifers? What are aquicludes? Groundwater Movement What are aquifers? What are aquicludes? Aquifers: permeable layers of soil Aquicludes: impermeable layers of soil