3. Where is groundwater stored?

Groundwater is stored in underground formations known as aquifers. Aquifers are geological layers that can hold and transmit water, typically composed of permeable materials such as sand, gravel, or limestone. The water in aquifers is found in the spaces between the particles of these materials or within fractures in solid rock. There are two main types of aquifers: 1. **Unconfined Aquifers**: These aquifers are directly recharged by surface water and are not overlain by a significant layer of impermeable material. The water table in unconfined aquifers can fluctuate based on precipitation and other factors. 2. **Confined Aquifers**: These aquifers are trapped between layers of impermeable rock or clay, which restricts water movement. They are recharged from specific areas where the confining layer is absent, allowing water to enter. Groundwater can also be found in other geological formations, such as: - **Perched Aquifers**: These are localized zones of saturation above the main water table, often formed by impermeable layers that trap water. - **Fractured Rock Aquifers**: These occur in solid rock formations where water is stored in fractures and joints. Overall, groundwater is a crucial resource for drinking water, irrigation, and industrial uses, and it plays a significant role in the hydrological cycle.