Where can you find aquifers that are underground?

Aquifers are found underground in various geological formations, typically located in sedimentary rocks like sandstone, limestone, or gravel. They can exist beneath the Earth's surface in areas such as river valleys, plains, or mountainous regions. Notable aquifers include the Ogallala Aquifer in the United States and the Great Artesian Basin in Australia. Groundwater can be accessed from these aquifers through wells and springs.