groundwater

groundwater - A Hidden Reserve: Groundwater Drinking water...

Info iconThis preview shows pages 1–20. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: A Hidden Reserve: Groundwater Drinking water Where is it from? Its endless, er..right? Not Everyone Has A Faucet Some People Have To Wait For Their Water Not Everyone Has Indoor Plumbing Hydrologic Cycle Earths water balance.powered by the SUN So where is all H 2 O on Earth Distribution of H 2 O on Earth Oceans: 96% Glaciers: 3% Groundwater: 1% Surface water (rivers & lakes): 0.1% Atmosphere: 0.001% Biosphere: 0.0001%- source of drinking & commercial water So where is all H 2 O on Earth Abundant - 70 times more fresh water below ground than above it. Constant - Groundwater is available even during dry periods. Widespread - Groundwater can flow from humid environments to where it is needed in dry regions. With all the worlds lakes and rivers, why is groundwater such a valuable resource? ... yet it must be managed like any other resource Porosity and Permeability Porosity % of material that consists of open spaces. Compaction and cementation reduces porosity Soil and unconsolidated sand 55% Clay 50% Shale 5% Gravel 20% Limestone 25% Limestone cavernous 100% Sandstone 10-30% Lowest in igneous & metamorphic rxs Porosity and Permeability Permeability is a measure of how easily a solid allows fluids to pass through it. A high porosity DOES NOT necessarily mean a correspondingly high permeability. Example of high porosity and low permeability - clay. Clay particles small sheets Clay have v high porosity as % pore space is high. Pores too small, + permeability is LOW. BUT Silt grains Very small pore space, not connected SECONDARY POROSITY + permeability from joints + faults Impermeable rock Small pore space, NOW connected How does surface water become groundwater? Transpiration Evaporation Water molecules slowly descend through the unsaturated zone due to gravity Some is held up by surface attractions { { Eventually it reaches zone where all pore space is filled with water SATURATED ZONE GROUNDWATER WATER TABLE boundary between unsaturated and saturated zone Recharge and Discharge of Groundwater Recharge - where groundwater is replenished Discharge - where groundwater flows from the surface Recharge area - Area where precipitation reaches the saturated zone Discharge areas - Where subsurface water is discharged to streams or to lakes, ponds, or swamps. Recharge and Discharge of Groundwater Recharge - where groundwater is replenished Discharge - where groundwater flows from the surface Recharge area - Area where precipitation...
View Full Document

Page1 / 63

groundwater - A Hidden Reserve: Groundwater Drinking water...

This preview shows document pages 1 - 20. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online