Which of the following materials would make the best aquifer?

The sediments that make up aquifers must be permeable and porous, allowing water to move through them. Water from an aquifer is generally extremely clean, as the fine sediments trap particles and bacteria, acting as a natural filter. The sediments that tend to make the best aquifers include sandstone, limestone, gravel and, in some cases, fractured volcanic rock.

Sandstone

Although sand is very porous, once it is compacted and cemented into rock it loses much of its pore space. Nonetheless, groundwater can still be transmitted through it joints and fractures. Sandstone can be very large since beds of sandstone can spread over extended areas. Many of the sandstone aquifers in the United States are embedded in shale and siltstone. As a result, the water in these aquifers are considered to be in confined condition because the surrounding rock is impermeable.

Limestone

Limestone is the most common type of carbonate-rock aquifer. Many of them begin as deposits in former marine environments, where the sediments lithify and compact. The cracks and joints in limestone are generally made as the rock slowly dissolves in slightly acidic water, leaving places for groundwater to flow. Sometimes caverns are formed that hold water and extend for thousands of feet. Often, the crevices and joints in limestone form a connecting network, further enhancing water flow.

Gravel

Gravel makes a good aquifer because it is extremely permeable and porous. The large pieces of sediment create significant pore spaces that water can travel through. Often, gravel must be surrounded by a less permeable soil type, such as rich clay or impenetrable rock. When gravel cements, however, it becomes conglomerated and loses its permeability.

Fractured Volcanic Rocks

In some cases, fractured volcanic rocks, such as columnar basalts, make good aquifers. Rubble zones surround volcanoes and consist of large particles, which, like gravel, are very porous and permeable. The variation among volcanic rock sediments largely result from the specific type of sediment, and the way it was ejected. Pyroclastic rocks have high permeability and large pores. Basaltic flows are usually fluid and have large pore spaces that allow water to pass through.

Which of the following would make for the best aquifer?

Answer and Explanation: b) Sandstone would be the best aquifer. Sandstone is a sedimentary rock, comprised of sand-size grains of minerals and rocks, that can hold water.

Which of the following would likely make the best aquifer quizlet?

Good aquifers include sandstone, conglomerate, well-jointed limestone, bodies of sand and gravel, and some fragmental or fractured volcanic rocks such as columnar basalt.

Which type of subsurface material would make the best aquifer?

Good aquifers are those with high permeability such as poorly cemented sands, gravels, or highly fractured rock. An aquitard is a body of material with very low permeability. In general, tightly packed clays, well cemented sandstones, and igneous and metamorphic rocks lacking fractures are good aquitards.

What type of soil is best for an aquifer?

Clay usually acts as an aquitard, impeding the flow of water. Gravel and sand are both porous and permeable, making them good aquifer materials.

What materials are in aquifers?

Many different types of sediments and rocks can form aquifers, including gravel, sandstone, conglomerates, and fractured limestone. Aquifers are sometimes categorized according to the type of rock or sediments of which they are composed.

What type of rock is a good aquifer?

Sedimentary rocks such as sandstone and limestone are good aquifers. Rocks that are impermeable make confining layers and prevent the flow of water. Examples of confining layers would be sedimentary rocks like shale (made from tiny clay and silt grains) or un-fractured igneous or metamorphic rock.