Permeability
	Permeability (k) is a geologic material's property which indicates its ability to transmit liquid under a hydraulic gradient. Another parameter, hydraulic conductivity (K), indicates the geologic material's ability to transmit water of a given temperature under a hydraulic gradient. I use these terms interchangeably as we are discussing the flow of water with little variation in temperature.
		1. Sediment
			Well-sorted sand or gravel
			Silt
			Clay
		2. Sedimentary rocks
		3. Crystalline rocks