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Science Assessment

• -Connor Williams-
• 8K

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Table of Context

• Plate Tectonic Activity
• Over-view of plate tectonic activity
• Transform boundaries
• Divergent boundary
• Convergent boundaries
• Creation or destruction
• Volcanoes
• - Over-view of volcanoes
• - History of volcanoes
• Rocks
• Igneous rocks
• Two intrusive igneous rocks
• Two extrusive igneous rocks
• - Process of change between rocks
• Reference

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Plate Tectonic Activity
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Over-view of Plate Tectonics

• Plate tectonics is the theory explaining how the
  movement of geologic plates causes natural
  (formations). The concept called continental
  drift by Alfred Wegener suggested that the
  continents are always in movement. The
  continental crust (located in the lithosphere) is
  the outermost layer that makes up the continents.
  The tectonic plates are floating on hot,
  malleable semi liquid. A boundary is where two
  plates. transform, divergent and convergent.
  Those are the three boundaries

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Transform Boundary

• A transform boundary/fault, also known as a
  strike-slip fault, is when two plates side
  past each other horizontally. This causes fault
  zones. (A fault is a crack in the earths crust.)
  An example of a transform fault is San Andreas
  Fault in California. Transform boundaries also
  cause earthquakes, as the edges are jagged and
  not smooth. As the two plates grind past
  each-other, the edges hit against each-other,
  locking the plates together. This causes stress
  at the fault line and it is released in a burst
  of energy (earthquake).
• https//www.elephango.com/index.cfm/pg/k12learning
  /lcid/11123/Transform_Boundaries

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Divergent Boundry

•  A divergent boundary/fault is when two tectonic
  plates move away from each other. When two
  oceanic plates diverge a crack in the ocean floor
  appears, magma then erupts from the mantle to
  fill the gap. This forms a raised ridge called a
  mid-ocean ridge. The magma also spreads forming
  new ocean floors and new oceanic crust. An
  example is the Mid-Atlantic Ridge.
• valley-like rift develops when two continental
  plates diverge. As the crusts widens and thins,
  valleys form around and in the area (like
  volcanoes) which become increasingly active. In
  the rifts streams and rivers flow forming narrow
  lakes. When it continues to spread some of the
  continental plate breaks cause new tectonic
  plates. An example is the Iceland rift valley.
• Plate Tectonics and Volcanic Activity National
  Geographic Society 

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Convergent Boundary

• Convergent boundary/fault is when two plates
  collide with eachother (collision boundary).
  There are three types of convergent boundaries.
  Oceanic and continental, continental and
  continental and lastly oceanic and oceanic.
• When two contrinel plates collides (since both
  plates are not dense it doesn't get pulled under
  the earth) the plates crunches together and fold
  at the boundary, lifting it up. This forms folded
  mountains and mountain ranges. An example is the
  Himalayan Mountains in Nepal.
• Plate Tectonics and Volcanic Activity National
  Geographic Society

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Convergent Boundaries

• Oceanic and oceanic Ones runs over the other
  ones which causes it to sink (into the mantle)
  forming a subduction zone. The subduction
  government plate is bent downwards forming a
  trench. The Mariana Trench is 11km deep.
• https//youtu.be/3p1N3JzJzFQ

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Convergent Boundries

• Oceanic and continental (called subduction) When
  two plates collide the denser plate is forced
  beneath the lighter plate causing a subduction
  zone. This is our volcanoes are formed. An
  example is Mt fuji.
• Plate Tectonics and Volcanic Activity National
  Geographic Society

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Creation or destruction
Convergent- colliding- destroys Divergent- spreading- forms Transform- sliding- neither
Plates move towards each-other Plates move away from each-other Plates slide against each other
Might cause earthquakes, form mountains, volcanoes, and other geological events and trenches Forms new crust, and rift valleys, volcanoes, earthquakes and volcanic mountain formations Causes earthquakes
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Volcanoes
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Over-view of Volcanos

• Volcanoes are formed when divergent boundaries
  release molten lava in the earths surface and it
  solidifies. At convergent boundaries, as
  meintioned before Volcanoes are formed when
  oceanic crust subducts under continental crust.
  As the oceanic crust sink, a deep trench, or
  valley is formed at the edge of the
  continent. The high heat and pressure from the
  crust sinking causes trapped water and gases to
  be released. This melts the base of the crust,
  forming magma. The magma rises to the surface and
  builds up in magma chambers, where is creates
  volcanoes. The magma turn turns into lava when it
  is erupted from the volcano.  Each flow covering
  the one before. This forms a cone shaped,
  mountain like figure. This process takes
  approximately 10,000 to 500,000 years. Oceanic
  volcanoes are formed from lava escaping through
  crack or fissures on the deep sea ocean. As the
  volcano erupt, magma (now lava) is ejected from
  the vent (opening) in the center of the volcano.
  The lava  spills downwards flowing the shape of
  the volcano. Ash, dust, rock fragment and gases
  are thrown into the air.

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History of Volcanoes

• Over 75 of the volcanos in the world are located
  in the Pasific Ring of Fire. an example is Mt.
  Fuji, which is the tallest, scared mountain in
  Japan.
• volcanoes do heaps of destruction however, The
  magma erupte from volcanos forms new ocean floors
  and oceanic crust. These land masses are created
  when lava cools, since molten lava is denser then
  water it floats on the surface.
• More then 80 of the crust's in the world are
  made from volcanoes.
• The volcano stays active if the subduction zone
  is active. If the subduction zone chanets directio
  n so it is no longer a convergent boundry
  (subducting) or when the entire plate has
  disappeared the volcano is no longer active.
  Subduction usually lasts for over millions of
  years. For underwater volcanoes the duration it
  is active depends on the mantle plume or the
  other source of melt.
• Scientists use satellites and GPS to input data
  about the volcanoes. (add).  

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Rocks
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Igneous Rocks

• Igneous rocks are formed from the solidification
  of molten rock material. The process is melting
  and cooling. The melting of the substance starts
  deep within the earth surface, then it slowly
  rises (while cooling) to the surface.
• There are over 700 igneous rocks 
• Igneous rocks are mainly utilised for flooring,
  landscaping and construction work.

Extra Igneous is the Latin word for fire. Most
magma never reach the surface.
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Igneous rocks are separated into two groups based
on the location of crystallization and
solidification.
Intrusive or plutonic igneous rocks Extrusive or volcanic rocks
Formed from the solidification of hot magma deep inside earths crust Cools and solidifies slowly due to the lack of air, this causes the composition of large crystals. The rate of cooling also effects the texture of the rock. Intrusive rocks have a coarse-grained texture. Rocks are formed along the sides of the lava tubes when magma (now lava) does reach the surface (usually due to volcanic eruptions or crack and openings in the earths crust) and it solidifies. Formed from lava Cools quickly due to the oxygen in the air, this causes tiny crystals to form that can only be seen with a microscope Extrusive rocks have a fine grain texture Molten rock that travelled through the lava tube to an exit point (pumice)
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How do 2 intrusive igneous rocks linked to
volcanic activity
Granite Gabbro
Made under the earths crust when magma solidifies Light-colored Large grains Mainly composed of quartz and feldspar Most common plutonic rock of the earths crust Is utilized in construction cause of its strength Cooling rate is slow Made under the earths crust when magma solidifies Dark coloured Coarse-grained Often found along mis-ocean ridges or ancient mountains or in oceanic crust Contains pyroxene and plagioclase Cooling rate is slow Is utilized for concrete, road based material and rail road ballast
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How do 2 extrusive igneous rocks linked to
volcanic activity
obsidian pumice
Made above the earths crust from cooled lava A natural volcanic glass Glassy lustre Glassy texture Usually black Minimal crystal growth Found in areas with volcanic activity Is ulistied to make weapons, implements, tools and mirrors Fine grain Made above the earths crust from cooled lava Froth like volcanic glass Used to remove dry, dead skin Rapidly cooled, no time to crystallize Very light grey to medium grey in colour A lot of empty gas bubbles Looks like a sponge Is formed when volcanoes erupt explosivly Fine grain
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Process of Change in Igneous Rocks
Metamorphic rocks Sedimentary rocks
Igneous rocks turn into metamorphic rocks by the process of heat and pressure. When massive amounts of heat and pressure are applied to an igneous rock, it compacts and becomes a metamorphic rock https//socratic.org/questions/how-can-igneous-rocks-become-metamorphic-rocks Igneous rocks turn into sedimentary rocks by the process of weathering and erosion. When the igneous rocks is broken down by weathering it is compressed and compacted beneath the ground. This forms a sedimentary rock. https//www.britannica.com/video/73160/Earth-surface-crust-rock-cycle-process
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References
This Photo by Unknown Author is licensed under CC
BY-NC
This Photo by Unknown Author is licensed under CC
BY-NC
This Photo by Unknown Author is licensed under CC
BY-NC
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