Charbeneau, 2000.

porosity

Figure 15.1

Types of Porous Media

Freeze and Cherry, 1979.

n = VV / VT = Vol Voids / Total Vol

Bedient et al., 1999.,

Porosity - not good indicator of flow

Freeze and Cherry, 1979.

= pressure headz = elevation headh = total head

Pressure and Elevation Heads - Field

Two Confined Aquifers with Different Heads

Charbeneau, 2000.

Groundwater will tend to flow from the top aquifer to the bottom aquifer.

We can’t make any conclusion about horizontal head gradients from this picture.

Horizontal and Vertical Head Gradients

Freeze and Cherry, 1979.

Other Aquifer Features

The Major Aquifers of Texas

Carrizo-Wilcox EdwardsGulf Coast

Ogallala

Recharge

Natural• Precipitation• melting snow• Infiltration by

streams and lakes

Artificial• Recharge wells• Water spread over

land in pits, furrows, ditches

• Small dams in stream channels to detain and deflect water