Untitled Flashcard Set

Physical geography: 


Geologic History 


Precambien: 

  • “Earliest life” 4600 MYA

  • 1st living multi-cellular organisms

Paleozoic:

  • “Anicent life” 570 - 245 MYA

  • Complex organisms such as fish, amphibians, and mammals evolved

Menozoic:

  • “Middle life” 245-66 MYA

  • The break up of the pangaea

  • Dinosaurs and reptiles evolved

  • First know flowering plants and animals, and mammals

Cenozoic: 

  • “Recent life”

  • Ice age

  • Shaping of the continents

  • Humans and mammals evolved


Continental drift: Wegener's method

  • He saw a jigsaw puzzle fit between south africa and south america

  • He found fossils of the same plants and animals of the same age and species on different continents

  • He found the mountains of the same structure and age split up on both sides of the atlantic ocean 

  • Ice sheets covered india, south africa, aus, and south america (warm today) and  he believed these countries were once closer to the north pole


Pangaea

  • 200-300 million years ago, plates were structured in a certain way so that the continents were once together

  • The land mass formed a “super continent” which is called the pangaea


Plate tectonics


Divergent: 

  • There are zones where two plates move away from each other creating an opening, usually allowing magma from the volcano to spill out from the mantle and solidify as new crust

Convergent: 

  • It is when one plate goes under another, called subduction, which forms a deep. The long, narrow zone between the two plates is called the subduction zone

Transform:

  • The transform plate boundaries grind past each other side by side, which mostly creates the California earthquakes   


It is thought that the uneven distribution of heat causes the convection currents to move the plates


Tectonic plates can pull apart, collide, or scrape past each other


Volcanos

  • Volcanos occur when one plate is pushed under another, that creates an opening in the hearts crust (kilauae and moana Loa in hawaii usa)

Earthquakes: 

  • Earthquakes occur when two plates grind against each other, which causes friction, and the trembling and the shaking movements of the earthquakes (san andreas fault)  

Tsunamis: 

  • Tsunamis are underwater earthquakes that have high magnitude which causes a tidal wave (the 2011 japan tsunami)

Mountain ranges: 

  • Mountain ranges occur when two plates are pushed against each other and “fold the crusts". The hot spots are the convection currents that make the plates come together and build a mountain (west coast mountains/the rockids) 


Earth's interior crust:


Crust/listhosphere

  • It is the outermost layer of the earth, and it contains the entire crust on the top most of the mantle

Asthenosphere

  • It has the same materials of the crust,but the pressure and heat is increased. It is not liquid but moves like heated metal, so it is somewhat liquid 

Mesosphere

  • At this level, the pressure really starts to build, which restricts the molecules ability to move, thus making it rigid

Outer core

  • Extremely high temperatures melt the metals contained into liquid form 

Inner core: 

  • It has extremely high temperatures and composes of mosytly metal. There is so much pressure at this depth, that even though the temperatures are beyond its melting points of the metal in the inner core, because of the high pressure squishes everything down into a solid


The rock cycle: 


Igneous rocks:

  • They form when magma cools and hardens. Magma that erupts on the surface is called lava. Examples are granite, basalt, and obsidian 

Sedimentary rocks:

  • They form particles called sediment, which are worn off of other rocks. The sediment gets turned into rocks by being buried and compacted by pressure from the weight above it. They also often contain fossils. Examples are sandstone, limestone, and shale

Metamorphic rocks:

  • They are rocks that have been transformed by great heat or pressure. It is buried deep into the earth's crust and sometimes happens when mountains are being made or where two plates grind against each other. Examples are glass, marble, and gneiss

 7 landforms: 


  • Canadian shield

  • Appalachian mountains

  • Innuitians mountains

  • Great lakes - st lawrence river

Hudson bay - arctic lowlands

  • Western cordillera]interior plains