A good aquifer is one that carries a large amount of water and recharges quickly. Some aquifers are even under pressure so that little if any work is required to bring water to the surface. An aquifer is any body of groundwater into which a well can be dug.Know More
Aquifers are buried porous rocks or masses of unconsolidated material, such as gravel, sand or silt, that are saturated with water. When one digs into such a rock or mass of material, water seeps into the hole, forming a well. When the layer of water-bearing material has porous materials above or beneath it, it's not under much pressure, and energy must be used to obtain the water. In artesian wells, however, the layer of water-bearing material is sandwiched between non-permeable materials, such as granite or clay. In these cases, the water is under pressure.
Aquifers have limited supplies of water and rely on precipitation to be refilled. Different aquifers refill at different rates depending on the amount of precipitation and the nature of the overlying materials. Human overuse of aquifers can deplete them or, in the case of coastal aquifers, cause saltwater to seep in, rendering them unusable for drinking or agriculture.Learn more about Layers of the Earth
An unconfined aquifer is a source of underground water that seeps through a permeable layer of dirt or sand directly to the ground surface above. Since the pressure of such aquifers is equal to or less than atmospheric pressure, drilling may not result in increased water levels in the area.Full Answer >
Continental plates are tectonic plates that lie under surface land masses. Tectonic plates are parts of the planet's crust that lie far below the sea around the world, and there are two types of plates: continental plates and oceanic plates. Note that some plates run under the ocean, and the continents as defined by geography.Full Answer >
The three layers of the earth, in order from outside to inside, are the crust, the mantle and the core. The mantle is the thickest and most massive layer, while the core has the highest temperatures of anywhere in the planet.Full Answer >
While iron and nickel form the liquid outer layer of Earth's core, the solid inner core is made mostly of iron. The iron in Earth's core is what gives the planet its magnetic field.Full Answer >