Explain why hot springs form and what makes a geyser erupt.

Hot springs and geysers are natural geological features that involve the flow of heated water from the Earth's interior to the surface. They are usually found in areas where volcanic or geothermal activity is present. To understand their formation and eruption, we need to delve into the processes occurring under the Earth's surface.

Hot springs form when groundwater, which naturally seeps into the Earth's crust, comes into contact with heated rocks or magma chamber below the surface. The heat source can be due to volcanic activity or the Earth's natural geothermal gradient. 1. Groundwater percolates down through permeable layers of rock and soil, reaching deep into the Earth's crust. 2. As the water travels deeper, it comes into contact with heated rocks or magma chambers. 3. The water absorbs the heat, causing its temperature to rise significantly. 4. The heated water becomes less dense and starts to rise, making its way back to the surface through cracks and fissures in the rocks. 5. At the Earth's surface, the hot water emerges and forms hot springs.

Geysers differ from hot springs due to their unique underground system, and the process of heating, pressure build-up, and sudden release of steam and water. The formation and eruption of geysers involve the following steps: 1. Groundwater percolates down through layers of rock and soil, similar to the hot springs process. 2. The water is heated by rocks or magma chambers deep below the Earth's surface. 3. The heated water starts to rise and collects in a series of underground fissures and chambers that are filled with permeable rocks. 4. Due to the unique configuration of the underground system, water and steam get trapped in these fissures and chambers, causing pressure to build-up. 5. When the pressure becomes too high, the superheated water and steam forcefully push through the restricted openings to the surface, causing a geyser eruption. In summary, hot springs form when groundwater comes into contact with heated rocks or magma and rises back to the Earth's surface, while geysers erupt due to the unique underground configuration, heating, and pressure build-up that forces the heated water and steam to escape suddenly.