Download Chapter 1 Review answers

World Geography 3200 Chapter 1 review
Lithosphere can be divided into two layers, one under ocean basins (sima) and one making up
continents (sial)
Rocks of continents are also called crust
Asthenosphere- upper 200-300km of upper layer of the mantle is called the asthenophere
- is in a plastic state, sometimes acting like a liquid
The study of earthquakes, known as seismology
lithosphere (zone at the Earth’s surface)
The high areas, low spots, and flat regions together are called the topography of Earth’s surface.
Magma-molten rock found below earth’s crust, which can give rise to igneous rocks.
Lava- magma that has flowed over Earth’s surface.
vent- an opening in the crust through which volcanic material flows.
EarthquakesVent- an opening of the crust out of which magma, ash, and gases erupt. (Most volcanoes are located
at plate margins).
Sea-floor spreading: the creation of new crust as magma rises up at a plate margin. The magma
creates new oceanic crust as the far end of the plate moves away.
Plates: the pieces of crust involved in the sea-floor spreading process.
Plate tectonics: the movement of plates. The movement of some plates causes earthquakes and
volcanoes.
Patterns of plate movement:
1. compressional force: occurs when plates move towards each other, sqeezing together which
causes rock layers to bend, warp, or be pushed upwards.
2. tensional force: occurs when plates break apart, moving away from or past each other, which
sometimes forms a trench as one plate drops downward.
2. Lithosphere can be divided into two layers, one under ocean basins (sima) and one making up
continents (sial)
Plains- one type of flat region, frequently found along coastal areas or at lower elevations. They
have a gentle slope and no local relief for 30m or more. (Figure 1.5)
Plateaus- another type of flat region, raised upward into higher elevations by movements of Earth’s
crust. Found in the interior regions of continents, and are sometimes located within or between
mountain ranges.
Hills- height of less than 300m, made up of rock piles and soil left behind by stream or glacial
erosion.
Mountains- height of more than 300m, rock layers are badly deformed, most mountains occur in
long linear chains called ranges.
Fold mountains--anticline: an arch-like upfold (peak) in buckled, bent or contorted rock. Syncline:
a downfold (trough) of rock layers.
fold mountains: process whereby layers of rock bend, buckle, and are pushed upwards when they
collide with another plate is called folding. (Folding =fold mountains)
mountains formed by faulting: when plates are compressed against each other, intense pressure, or
the brittleness of the rock layers involved, may cause rocks to fracture, or break apart.
4. Normal fault- if a plate on one side of a fault drops down lower than the plate on the other side.
Rift valley- 2 normal faults occur parallel to each other; the broken plate between the faults drops
down as the broken plates move away from each other, creating a valley
Block mountain- is formed when the land between parallel faults rises.
Reverse fault- if simple rock layers around a fault push against each other instead of pulling away, one
block can be pushed up over the other.
Overthrust fault- occurs when the folded layers of a fault are pushed up and thrust over layers on the
fault’s other side.
5. three major rock types:
1. igneous rock – forms when molten substance underneath the surface, called magma or lava,
cools down and crystallizes, i.e. volcanoes erupt and the liquid lava hardens.
2. sedimentary rock – forms when groups of rock pieces merge and cement together, i.e. rivers
transport sediment (pebbles, rock particles etc.) into lakes or seas. The layers of sediment build
up on the sea floor and are pressed together by the weight of the layers on top they then merge
and cement together.
3.
metamorphic rock- rocks that have already been created are transformed by great heat or
pressure (chemical composition is altered).
6. Valleys:
1. V-shaped
formed by river erosion
2. Flat-bottomed
formed by river erosion
3. U-shaped
formed by glacial erosion
4. Rectangular with steep sides
formed by faulting or folding
7. Plains:
1. alluvial
formed by river action
2. lacustrine
were once the beds or bottoms of lakes that no longer exist
3. outwash
created by sediment washed out of melting glaciers
8. volcanic eruptions, earthquakes occur at (or close to) plate boundaries.
9.Theory of Continental Drift.
1. Alfred Wegener –1924: all Earth’s continents were joined in one single mass called Pangaea.
The Pangaea broke into 2 sections about 200 million years ago. These 2 then split into smaller
pieces that look like the continents of today. (Figure 1.8) He thought that the force that pushed
the continents apart was related to the force that triggers earthquakes and volcanoes around the
place where the break between continents occurred.
2. J.Tuzo Wilson-1960s (a Canadian scientist) looked at Wegener’s theory. He observed that
earthquake and volcanic activity often occur in mid-ocean regions as well as on coast. These
mid-ocean regions have ridges, the ridges on either side match. He said that volcanoes erupt in
the middle of the ocean creating new crustal material in the form of ridges. These ridges split
apart the ocean floor and pushed continents apart.
Evidence of tropical forests in Antarctica because of presence of coal deposits.
Continents look as if they fit together like a puzzle.
10. Three types of volcanic cones:
1. ash-and-cinder cones:
shape: symmetrical with steep sides and a large crater
lava: thick, slow-flowing, fast hardening
volcanic eruption: explosive
2. shield cones:
shape: broad flat cones
lava: very thin, liquid lavas
eruption: mild; little or no ash and cinder
3. composite cones:
shape: small cones
lava: layers of ash and cinders intermixed with layers of lava
eruption: periods of both explosive and quiet activity.
11. Earthquakes affect developing countries more than developed ones because:
1. earthquake zones in developing countries are more populated and more people are crowded
into substandard buildings
2. developing countries often do not have the resources or relief plans for responding to a natural
disaster.
Developed countries have done things to protect towns and cities in earthquake prone areas by:
-making earthquake-proof structures
-enforcing strict building codes
-developing emergency response plans for people
12. Most mountain ranges are found on the margins (coasts) of continents. This is where the oceanic
plate meets the continental plate, which results in mountains forming when the plates are compressed
against each other.