Endogenic Processes

• Scientists infer the temperature of the Earth by observing the speed of seismic waves that pass through the earth allowing them to determine the density and stiffness of the rocks, and match up those properties of known substances at elevated temperatures and pressures.
• The mantle is composed mainly of silicate minerals such as olivine (Mg2SiO4), pyroxene (Ca(Mg,Fe)Si2O6), garnet (Ca3Al2Si3O12), and spinel (MgAl2O4).
• The uppermost part of the mantle is called the lithosphere, which consists of rigid plates that float on top of the asthenosphere.
• A volcano is a vent that serves as the conduit of molten rocks that reaches the Earth's surface.
• Magma are molten rocks that are formed beneath the Earth's surface.
• Viscosity is the degree of resistance to flow.
• Magma is viscuous
• Lava is magma that emerges at the surfaces
• Magmagenesis is the formation of magma
• Decompression Melting occurs when hot mantle rock ascends and moves into zones of lower pressure which results to less pressure exerted on rocks
• Flux melting is when water vapor reacts with the rocks and weaken or break their bond and cause it to change from solid to liquid state and usually occurs in subduction zones.
• Heat Transfer melting is when very hot magma from the upper mantle could rise and cause melting of the rocks in the lower crust which has lower temperature
• An example of heat transfer is putting a metal spoon in a cup of hot water
• The three types of volcano are stratovolcano, shield volcano, and cinder cone
• Stratovolcano is also known as composite volcano because they have alternating layers of lava flows and ash deposits
• Shield Volcano is characterized by gentle slopes and low elevation
• Stratovolcano is also known as composite volcano because they have alternating layers of lava flows and ash deposits that build up over time
• Shield Volcano is characterized by low viscosity lava that flow easily and form flat-topped mountains
• Cinder Cone is formed by explosive eruptions that eject small fragments of rock called tephra
• Cinder Cone is formed through explosive eruptions where fragments of molten rock fly out of the vent and fall back down around the opening
• A caldera is an explosion-formed depression on top of a volcanic mountain
• Lahars are mudflows composed mainly of pyroclastic material mixed with water
• Ash flow is a type of pyroclastic flow that occurs during an explosive eruption and consists of fine-grained particles mixed with gases
• Cinder Cone is formed by explosive eruptions where fragments of rock and gas shoot out into the air and fall back to earth around the vent
• Cinder Cone is formed from explosive eruptions where the magma breaks apart into small fragments called tephra or pyroclastic material
• A caldera is an explosion crater caused by the collapse of the ground above a chamber of molten rock
• Pyroclastic Flow is a fast moving mixture of gas, rock fragments, and ash that can travel at speeds exceeding 700 km/h (435 mph)
• Lava Dome forms when magma rises to the surface but does not reach the ground, instead it cools and solidifies within the volcanic conduit.
• Calderas are caused by magma chambers collapsing when their roofs are destroyed during large explosions
• Partial melting is when the rocks are not fully melted because rocks are composed of different minerals which have different eutectic temperatures
• Eutectic temperature is the melting point of the rock
• Decompression melting occurs at divergent boundaries
• Heat Transfer occurs at convergent boundaries
• Flux melting occurs at subduction zones
• Flux melting can also be caused by the addition of water and carbon dioxide
• Eruption is the event when lava spews out of the volcano
• Pyroclastic debris are broken fragments of lava
• Pyroclastic flow deposit are pyroclastic debris that flow on the slope of the volcano
• Volcanic ash are very fine particles composed of fragments of existing rocks
• Bombs are blobs of lava that are thrown into the air and developed a smooth shape fragment