which can be excluded from the list of underground materials that holds water in the Ogallala aquifer

Answer 1

Materials that can be excluded from the list of underground materials that hold water in the Ogallala aquifer are:

1. Sand and gravel: Sand and gravel are highly permeable materials that can hold and transmit large volumes of water. They are often the main components of aquifers and play a significant role in storing water in the Ogallala aquifer.

2. Silt and clay: Silt and clay have lower permeability compared to sand and gravel, but they still contribute to storing water in the aquifer. These fine-grained materials can hold water in the small spaces between particles and through capillary action.

3. Porous rock formations: Certain porous rock formations, such as sandstone and limestone, can also act as aquifers and store significant amounts of water. These rocks have interconnected pore spaces that allow water to flow and be held within the aquifer.

4. Shale: While shale has low permeability and is not considered a primary aquifer material, it can still contribute to water storage in the aquifer. Shale serves as an impermeable layer that prevents water from migrating vertically or horizontally between aquifers and helps define the boundaries of the Ogallala aquifer.

Overall, all the mentioned materials play a role in holding water within the Ogallala aquifer.