Subsidence and Karst

Question 1

Causes of Subsidence

Answer 1

• oil/natural gas extraction
• mining
• dissolution of limestone
• groundwater-related

Question 2

permafrost

Answer 2

-ice in the ground

Question 3

what can the melting of ice cause?

Answer 3

• land subsidence

- damages to infrastructure

Question 4

Major Areas of Subsidence

Answer 4

East Coast(NJ to Florida)
Texas/Loisiana
California/Arizona/Nevada

Question 5

Groundwater(definition and amount)

Answer 5

water in spaces within bedrock and regolith

0.6% of all water on earth

Question 6

Water Table

Answer 6

is the top of the saturated zone

Question 7

Does the water table follow?

Answer 7

the general surface topography

Question 8

What balance does the water table depend on?

Answer 8

recharge and discharge

Question 9

Porosity

Answer 9

Is the volume of rock with pore spaces

Question 10

Permeability

Answer 10

is the interconnectedness of the pore spaces

Question 11

What type of permeability does an aquifer have?

Answer 11

high permeability and porosity

ex.sandstone

Question 12

What type of permeability does an aquiclude or aquitard have?

Answer 12

low permeability ex.shale

Question 13

What is caused by the pumping of water from underground?

Answer 13

cone of depression

Question 14

Overpumping causes what?

Answer 14

subsidence

Question 15

What is the savior of the dustbowl states?

Answer 15

Ogallala aquifer

Question 16

Karst

Answer 16

occurs when some particular bedrock is dissolved by groundwater

• causes hummocky topography(hilly/bumpy)
• causes caves and sinkholes