Caverns
Wetland
Area where the water table is close to the ground surface
What states have a lot of karst terrain?
- Florida - Kentucky - Great valley of PA
What are the two controlling factors on flow?
- Porosity - Permeability
What are some examples of aquifers?
- Sand and gravel deposits - Jointed or fractured rocks - Cavernous limestones
What has to happen in order to make caves?
A lot of groundwater needs to flow through the rocks
What is an aquifer?
A rock with both high porosity and high permeability "water carrier"
What kind of groundwater flow is required to form caves?
Acidic Water- groundwater tends to be acidic; acidic water dissolves limestone quickly
Dissolving process 4
Acidic water dissolves limestone around it
What is created in extreme versions of karst terrain?
All the caves collapse and create towers of limestone
What is a disappearing stream?
Allow rainfall to travel quickly into caves and groundwater, often disappear through sinkholes
Stream
Anywhere the water table lies above the ground surface
What is cave breakdown?
Blocks of rock that fall from the roof or the sides after the cave forms
Stalactites
Grows down from the ceiling. Water evaporates before leaving the ceiling; calcite left behind
Stalagmites
Grows up from the ground. Water drips to the floor, evaporates, calcite left behind
Spring
Intersection of water table and hillside
What is karst terrain?
Lots of sinkholes and springs; not many rivers
Dry caves
Most caves are dry; tend to be plain and undecorated
Completely water-filled caves
Other caves stay very wet; still forming
Part wet and part dry caves
Part wet, part dry caves are typically the ones that contain flowstone (cave formations)
Dissolving process 3
Reaches water table; begins to pool (sit) there
What is the Water Table?
Surface that separates damp rocks from saturated (wet) rocks
Permeability
The ease of flow through the rock pores (pathways)
Caves don't last forever. What happens to them all eventually?
They all collapse and form sinkholes
What is karst?
Topography created in areas with lots of caves
What are caves?
Underground holes formed when limestone (not the only rock but the majority) is dissolved by groundwater
Draperies
Very thin layers of flow-stone that hang in mid-air
What is groundwater?
Water that flows underground through the pores of rocks and soils
Dissolving process 1
Water works through soil; reacts with CO2 (carbon dioxide)= acidic
Under what conditions does limestone dissolve best?
Wet, water breaks it down easily
Columns
When stalagmites and stalactites meet.
Flowstone
When water dissolves limestone, then trickles into cave where it can dry up and leave behind layer of calcite
Dissolving process 2
Works down through joints and fractures of limestone
Porosity
amount of space available for water to flow in
What creates cave formations?
this occurs when water dissolves limestone and then leaves behind a layer of calcite.