This one hour lab activity is used in the undergraduate hydrogeology course. The materials are common laboratory items and can be put together in a couple of hours.

Students should have been introduced to the concept of storage. The laboratory description includes a poroelastic formulation of specific storage.

The activity can either be a lecture demonstration or a one-hour laboratory to demonstrate the concept of storage.

The goal is to provide a poroelastic formulation of storage, and thereby unify concepts of geomechanics with those of hydrogeology.

The activity promotes quantification of the specific storage in terms of constitutive equations.

The activity promotes development of laboratory measurement skill.

The goal of this experiment is to measure the specific storage S_s of a balloon, which simulates aquifer elasticity. The experiment is designed to give observational meaning to the variable, increment of fluid content, and the influence of the state of stress on the specific storage. Increment of fluid content is the poroelastic variable defined as the amount of water added to storage per unit bulk volume. It is analogous to quantity of heat added to a unit volume of a material. Specific storage can then be expressed rigorously as the ratio of increment of fluid content divided by the change in head with specified external stress or strain conditions on the REV.

Successful evaluation of the storage of a balloon.

These are web links to the same files in the 'Download Teaching Materials' section above.

Lab 5 - Aquifer Elasticity and Specific Storage - Web page containing lab activity
Theory of Linear Poroelasticity with Applications to Geomechanics and Hydrogeology - Textbook chapter (PDF)