### Equation

greenspun.com : LUSENET : Introductory Geology, Oswego State : One Thread

In my study session with the tutor, she mentioned Darcy's Law. I wasn't in class that day we learned it, so could someone please explain to me what it is??

-- andrea (agibbs@oswego.edu), October 30, 2002

I did not cover Darcy's Law in detail in lecture. Darcy's Law simply states that the rate of groundwater flow (in terms of volume of water flowing through an aquifer cross-section per unit time -- sort of like river discharge, and the symbol for groundwater flow rate is Q, same as for river discharge) depends on three things: 1) the hydraulic conductivity, K (almost the same as permeability) of the aquifer; 2) the hydraulic gradient, h/l (a measure of how much hydraulic head varies from place to place in the aquifer); 3) the cross-sectional area, A of the aquifer.

Darcy's Law is Q = -K x h/l x A

The minus sign indicates that groundwater flows from higher head to lower hydraulic head. The rest of the equation says that groundwater flow rate, Q, will be faster if K (permeability) is high, h/l (hydraulic gradient) is large, and the aquifer has a big cross-sectional area (A).

Does that help?

-- Sharon Gabel (gabel@oswego.edu), October 31, 2002.

I am alittle confused about the Darcy's law also can someone give me an example of how it is used? Also will it be on the test??

-- Vanessa Azevedo (Nessi1024@aol.com), October 31, 2002.