Science Q3 G9

• Volcanoes Geocentric model of Aristotle
• Named after god of fire volcan. And name from Vulcano
• Present: heliocentric model is sun

  Past: geoheliocentric model is sun and earth
• Geomorphology study of the relief factors of earth crust
• 3 layers

  1. Crust
  2. Mantle
  3. Inner core and outer core
• 3 primarly geological forces

  1. Diastrophism
  2. Erosion
  3. Volcanism
• Diastrophism cause: internal force of heat

  -vertical and horizontal movement of the earth's crust that result to mountain.

  -large movement of the portion of the earth's crust
• Erosion cause: exogenous forces

  • Physical removal of rock or land masses
  • Because of the running water, glacial ice and wind
• Volcanism (volcanity)

  • Discharge of magma, hot water, and streams
  • Discharge of volcano
• Geotric (geothermal)

  • Heat from the ground
• Active volcanoes in the world are 859.

  654(150%)- are located in the circle of fire or ring of fire
• Paricutin- it is located near the town of san juan, mexico

  • In February 1943 first eruption
  • Declared as active volcano or violent explosion
  • It can grow 336(1,100F) but in 8 years added 88cm(1,943)
  • After 9 years in 1952 it is called dormant due to it's inactive
• The volcano is almost the same in mountain but the volcano is more complicated
• Cone- the mose striking part of the volcanoes, usually composed of lava and pyroclastic materials. Viscous and slow moving grantic magma forms  high sided step cones while fast moving basaltic magma creates low to almost flat cones
• Vent- the opening through which an eruptions takes place, the main part of a volcano supplies the magma from the underlying source to the top of the volcano
• Magma chamber- the large underground pool of liquid rock found beneath the earth's crust
• Crater- a basin like depression over a vent at the summit of the cone
• Calder- a volcanic depression much larger than the original crater
• Lava- the rock of magma expelled from a volcano during an eruption. It's temperature upon ejection can reach up to 700°C, hence it flows until it cook and hardens
• Dikes- the barrier or obstacle in a volcano.
• Sills (intrusive sheets)- they are solidified lava flows that originally forced their way between and parallel to older layers of rocks
• Conduit- a channel or pipe conveying liquid materials such as magma
• Flanks- the side of the volcano
• Summit- the highest point or apex of a volcano
• Throat- the entrance of a volcano
• Ash clouds- expelled into the atmosphere; volcanic ash or ash cloud is composed of polarized rock and glass created during the eruption
• Lahars- mudflows formed when water mixes with pyroclastic material from an erupting volcano, causing it to flow rapidly downhill
• Pyroclastic flow- a fast moving current of hot gas and rock fragments ejected by explosive volcanic eruptions
• Tephra- any fragmental ejecta produced by explosive volcanic eruptions
• Volcanic bombs- large pieces of lava thrown out of a volcano during an eruption
• Composite/strato volcano- tall steep sided volcano built up of alternating layers of hardened lava and solidified ash and pumice
• 
  

  • Dormant volcano: inactive volcano that has not erupted in 2,000 years
  • Extinct volcano: volcano that has not erupted in 10,000 years
• Volcanic materials:

  • Bombs
  • Tephra fall
  • Lahar
  • Ash
  • Clouds
• Processes related to volcanic activity:

  • Proclastic flow
• Flat cone: magma ejected fast moving
• High sided step - magma ejected fast moving
• Volcano

  • They are build through lava, ash flows, and tephra
• Formation by subduction: through the colasion of plates
• Formation by distension: cause by hot spot near the earth's outer
• • There are millions of volcanoes according to geology
  • There are 1,500 active volcanoes that have been recorded in 10yrs
  • There are 800 active volcanoes known today
  • 50-60 of which had erupted once in a year out of 800 which 20x in a year