Water Resources

Filter Total Items: 436
Date published: March 8, 2021
Status: Completed

Unconsolidated and semiconsolidated sand and gravel aquifers

Unconsolidated sand and gravel aquifers are characterized by intergranular porosity and all contain water primarily under unconfined, or water-table, conditions. They are grouped into four categories: basin-fill, blanket sand and gravel, glacial-deposit, and stream-valley aquifers. Semiconsolidated aquifers consist of semiconsolidated sand interbedded with silt, clay, and minor carbonate rocks...

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Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

List of unconsolidated sand and gravel aquifers

Unconsolidated sand and gravel principal aquifers of the United States, which are characterized by intergranular porosity and all contain water primarily under unconfined, or water-table, conditions.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

List of semiconsolidated sand and gravel aquifers

Semiconsolidated aquifers of the United States, which consist of semiconsolidated sand interbedded with silt, clay, and minor carbonate rocks.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Sandstone aquifers

Sandstone aquifers are more widespread than those in all other kinds of consolidated rocks. Groundwater movement in sandstone aquifers primarily is along bedding planes, but joints and fractures provide avenues for the vertical movement of water. Sandstone aquifers can be highly productive and provide large volumes of water.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

List of Sandstone Aquifers

Sandstone aquifers are more widespread in the United States than those in all other kinds of consolidated rocks. Fractures, joints, and bedding planes can store and transmit large volumes of water.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Sandstone and carbonate-rock aquifers

In scattered places in the United States, carbonate rocks are interbedded with almost equal amounts of water-yielding sandstone. In most places where these two rock types are interbedded, the carbonate rocks yield much more water than the sandstone.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Carbonate-rock aquifers

Aquifers in carbonate rocks are most extensive in the eastern U.S. Most of the carbonate-rock aquifers consist of limestone, but dolomite and marble locally yield water. The water-yielding properties of carbonate rocks vary widely; some yield almost no water and are considered to be confining units, whereas others are among the most productive aquifers known.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

List of Carbonate-Rock Aquifers

Carbonate-rock aquifers are most extensive in the eastern United States. Most of the carbonate-rock aquifers consist of limestone, and their water-yielding properties vary widely.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Igneous and metamorphic-rock aquifers

Igneous and metamorphic-rock aquifers can be grouped into two categories: crystalline-rock and volcanic-rock. Spaces in crystalline rocks are microscopically small, few, and generally unconnected. However, because these aquifers extend over large areas, large volumes of water can be withdrawn. Volcanic-rock aquifers have a wide range of chemical, mineralogic, structural, and hydraulic...

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Minor aquifers, confining units, and areas identified as "not a principal aquifer"

Aquifer maps often include large-to-small areas that are designated "minor aquifer," "not a principal aquifer," or "confining unit.” These are usually areas are underlain by low-permeability deposits and rocks, unsaturated materials, or aquifers that supply little water because they are of local extent, poorly permeable, or both.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Aquifer data: Explanation of spatial data formats

Supplemental information for hydrogeologic unit boundaries (framework) and groundwater recharge data provided through the Regional Groundwater Availability Studies of the National Water Census.

Contacts: Ask USGS
Attribution: Water Resources
Date published: March 8, 2021
Status: Completed

Central Valley aquifer

Central Valley is virtually one large, sediment-filled valley in California between the Coast Ranges and the Sierra Nevada. The aquifer system is divided into three subregions on the basis of surface-water basins.

Contacts: Ask USGS
Attribution: Water Resources