Earth science

• The endogenic processes on Earth take place within or in the interior of Earth.
• Caldera is a large cauldron-like hollow that forms following the evacuation of a magma chamber/reservoir.
• Thermal energy (heat) coming from the mantle is the driving force of these processes.
• These processes are responsible for earthquakes, development of continents, building of mountains, volcanic activities, and other movements related to Earth’s crust.
• Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet, which solidifies as igneous rocks.
• Magmatism includes any process that affects the melting or crystallization of a magma.
• Magma is formed from the melting of rocks in the earth’s lithosphere, about 30 to 65 km below the surface of the Earth.
• The temperature is high enough to melt the rocks and eventually forming the magma.
• Magmatism occurs at temperatures of 600°-1400°C and under intense pressure, causing the magma to flow very slowly.
• Magma also contains gases which are dissolved in the liquid, giving it its explosive character.
• When gases cannot escape readily, eruption is more explosive.
• The composition of the gases in magma is mostly water vapor, some carbon dioxide, minor amounts of sulfur, chlorine and fluorine gases.
• Viscosity, the resistance to flow, depends primarily on the composition and temperature of the magma.
• The type of magma can be determined depending on the silica (SiO2) content of the magma.
• Pyroclastic flow is a mixture of solid to semi-solid fragments and hot, expanding gases that flow down the flank of a volcano.
• Volcanism is the process that usually happens after magma is formed.
• Violence and calmness of a volcanic eruption are influenced by the silica and water content of its magma.
• The eruption lessens the pressure inside the magma chamber.
• Heavier-than-air emulsions that move much like a snow avalanche with a temperature up to 700°C.
• This is the most deadly of all volcanic phenomena.
• In the atmosphere "tephra" is more referred to as volcanic ash.
• Tephra is the magma that solidifies in the air forms volcanic rocks.
• Most magma chambers are beneath the surface of the Earth within the upper mantle and crust where the temperature and pressure conditions favor the molten state.
• Magma forms, develops and then collects in areas called magma chambers.
• Magmatism is a process that involves magma with higher silica content having higher viscosity.
• As the magma chamber experiences greater pressure, often due to more seeping into the chamber, the volcano erupts.
• Magma tries to escape from the source through openings in volcanoes or existing cracks on the ground called vents.
• The smoke released during eruption is a mixture of several gases and most of these are poisonous, including water vapor, carbon dioxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, hydrochloric acid, methane, and ammonia chloride.
• When it comes to temperature, magma with lower temperature has higher viscosity than those with high temperature.