Science

• Philippine Institue of Volcanology and Seismology (PHIVOLCS) is the government agency that monitors and studies volcanoes and earthquakes.
• magma inside the volcano has high temperature
• there are 3 general volcanic types according to the shape of their cones, namely, shield volcano, cinder cones, composite cones
• the external parts of a volcano are summit, slope, and base
• at the summit, there is an opening which may either be a crater or a caldera
• a crater is a funnel-shaped opening at the top of a volcano
• a caldera is formed when a part of the wall collapses following an explosive eruption
• taal has 47 craters while mayon only has one
• viscosity is the property of the material's resistance to flow
• the viscosity of magma decreases with temperature
• the higher the temperature of a magma is, the lower its viscosity is
• magmas with high silica content are more viscious than those with low silica content
• the loss of gases makes magma more viscious, forming a dome or a columnar
• lava with less silica content has low viscosity that it can travel a great distance, forming a thin sheet of lava
• lava with high silica content is too viscious to travel far, and tends to break up as it flows
• lava with low amount of gases and high silica content is very viscious and does not flow out at all as it rises, forming a columnar plug in the vent
• lava with low amount of gas as it rises has high viscosity that it piles p at a vent resulting in a dome
• there are 5 types of volcanic eruptions namely phreatic or hydrothermal, phreatomagmatic, strombolian, vulcanian, and plinian
• phreatic or hydrothermal eruption occurs when water from underground reservoirs heats up and turns into steam which causes an explosion
• phreatomagmatic eruption happens when hot rock meets groundwater causing an explosive reaction
• strombolian eruption is characterized by small fountains of lava ejected intermittently from vents
• plinian eruption is characterized by large amounts of ash being thrown into the air
• vulcanian eruption is characterized by violent explosions producing dark clouds of ash and smoke
• shield volcanoes are formed when magma rises through cracks in the crust and cools
• cinder cones are built from ejected fragments, they have a steep slope, wide crater and are the most abundant of the three major volcano types
• composite cones or stratovolcanoes are large, neraly perfect sloped structure formed from alternate solidification of both lava and pyroclastic deposits
• dearalc, it is a volcanic crater that is formd when a part of the wall of the crater collapses following an explosive eruption
• magma are molten rocks inside the earth
• lava, magma that has been ejected out of a volcano
• mauna loa is an example of shield volcano
• paricutin is an example of cinder cone
• mayon is an example of composite or stratovolcano
• active volcano that has atleast one record of eruption during the past 10,000 years
• a dormant volcano is an active volcano that is not erupting but supposed to erupt again
• there are 24 active volcanoes
• iraya, smith, babuyan claro, didicas, and cagua are examples of an active volcanoes
• inactive volcano are also called extinct or sleeping volcanoes. it is one that could erupt but has not erupted for more than 10,000 years
• anilao hill, batuan, uruit, tamburok, cabaluyan are examples of inactive volcanoes
• plate tectonics is the theory that explains how the continents were formed and moved around the world
• the imaginary group of stars

  constellations