GENERAL GEOLOGY

Detailed explanation-1: -Geysers form near areas of volcanic activity. Magma heats the water to extreme temperatures. The superheated water rises near the surface.

Detailed explanation-2: -Phreatic eruption-Phreatic eruptions are steam-driven explosions that occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or new volcanic deposits (for example, tephra and pyroclastic-flow deposits).

Detailed explanation-3: -Hot springs and geysers also are manifestations of volcanic activity. They result from the interaction of groundwater with magma or with solidified but still-hot igneous rocks at shallow depths.

Detailed explanation-4: -Hot springs are heated by geothermal heat-heat from the Earth’s interior. In volcanic areas, water may come into contact with very hot rock heated by magma.

Detailed explanation-5: -(Watch a video of submarine volcanoes erupting.) In any volcanic eruption, magma (molten rock beneath the Earth’s surface) rises from the depths of the Earth to the surface of the land or the seafloor. The magma contains dissolved gases, which form bubbles as the pressure on the magma is reduced during its ascent.