GEOLOGY

Detailed explanation-1: -Magma contains dissolved gases, which provide the driving force that causes most volcanic eruptions. As magma rises towards the surface and pressure decreases, gases are released from the liquid portion of the magma (melt) and continue to travel upward and are eventually released into the atmosphere.

Detailed explanation-2: -The molten rock is called magma. Within the Earth, the weight of rock causes pressure to increase with depth (imagine the weight, or pressure, on your body if a million rocks were sitting on top of you!). The greater the depth, the greater the pressure.

Detailed explanation-3: -Answer: Volcanoes are formed by eruptions of lava and ash when magma rises through cracks or weak-spots in the Earth’s crust. A build up of pressure in the earth is released, by things such as a plate movement which forces molten rock to exploded into the air causing a volcanic eruption.

Detailed explanation-4: -Volcanic eruptions are partly driven by pressure from dissolved gas, much as escaping gases force the cork out of a bottle of champagne. Beneath a volcano, liquid magma containing dissolved gases rises through cracks in the Earth’s crust. As the magma rises, pressure decreases, allowing the gases to form bubbles.

Detailed explanation-5: -Ninety-nine percent of the gas molecules emitted during a volcanic eruption are water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2). The remaining one percent is comprised of small amounts of hydrogen sulfide, carbon monoxide, hydrogen chloride, hydrogen fluoride, and other minor gas species.