BA 6th Grade Science Final--Earth

the amount of force placed on a given material
the process by which the shape of a rock changes because of stress
when stress squeezes an object
large mountain ranges
can form when compression squeezes rocks at a convergent place boundary
the bending of rock layers due to stress
a fold where both ends of the rock layer are horizontal
a downward, trough-like fold
an upward-arching fold in a rock layer
when rock layers break, the resulting surface they break and slide
normal fault
when tension pulls rocks apart, this is created
reverse fault
when compression pushes rocks together this is created; the hanging wall moves up relative to the hanging wall
strike-slip fault
when opposing forces cause rock to break and move horizontally this is created; related to transform boundaries
foot wall
when a fault is not vertical, a hanging wall and this are formed
normal fault
the hanging wall moves down relative to the foot wall in this; the tension pulls the fault apart (divergent)
mountain ranges
when tectonic plates collide, folds and faults can become these
folded mountains
this kid of mountain range is formed when rock layers are squeezed and forced upward; Appalachian, Himalyas and the Alps
fault-block mountains
this kind of mountain range is formed when tension causes large blocks of crust to drop down; like Sierra Nevada and Teton range
volcanic mountains
form when convergent oceanic crust sinks into the asthenosphere. The crust melts, forms magma and erupts
Appalachian Mountains
folded mountains
fault-block mountains
Ring of Fire
volcanic mountains
the rising of Earth's crust to higher elevations
the sinking of regions of the Earth's crust to lower elevations
when the Earth's crust slowly springs back to its original elevation
this is what happens to the ocean floor the farther the oceanic lithosphere is from a mid-ocean ridge
rift zone
a set of cracks that from when two tectonic plates are pulling away from each other
a substance composed of two or more elements
the reason less dense compounds make up Earth's crust while the densest compounds make up the core
the outermost layer of the earth
the "middle" layer of the earth
the innermost layer of the earth
oxygen, silicone, aluminum
three elements that make up most of the earth's crust
iron, calcium, magnesium
oceanic crust is denser than the continental crust because it contains more of these three elements
the mantle is composed of more of this element than the crust is.
ocean floor
where scientists look for clues about the mantle (because magma flows out of volcanoes there and there is more magnesium in the mantle, making it denser)
aluminum and silicone
the mantle has less of these elements than the crust
this element makes up most of the earth's core
one third
this much of the earth's mass is made up by the core
the outermost, rigid layer of the earth
a layer of slowly flowing rock in the mantle
outer core
the liquid layer of the core
inner core
the solid layer of the core
the strong, lower part of the mantle
tectonic plates
large pieces of the lithosphere that move around on the asthenosphere
jigsaw puzzle
tectonic plates fit together like this
continental, oceanic
two kinds of crust that a tectonic plate may contain
float and cover the surface, touch and move around, displace
ways in which tectonic plates floating on the asthenosphere are similar to ice cubes filling a punch bowl
seismic waves
vibrations from an earthquake; what scientists use to study earth's interior
continental drift
the hypothesis that Alfred Wegener used to explain why continents seem to fit together
according to wegener how many landmasses did all continents once form?
Wegener's hypothesis about the continents
they broke up and drifted to their current locations
Wegener's name for all of the present continents that he thought were once joined 245 million yr ago in a landmass
Laurasia, Gondwana
when the single landmass split into 2 huge continents about 180 million yr ago, Wegener call the countries these names
continents today
when the two continents split 65 million years ago, Wegener said this was formed
lack of evidence
the reason that many scientists rejected Wegener's hypothesis for the separation of the continents
crust is formed
this happens in the process of sea-floor spreading when magma rises to the earth's surface and solidifies
sea-floor spreading
process of forming new oceanic lithosphere as magma rises to the surface
mid-ocean ridges
areas where sea-floor spreading takes place
magnetic reversal
process that happens when earth's magnetic poles change place
continental drift
theory that explains how continents reached their current locations
magnetic reversal
rock on the ocean floor provided the final prof of sea-floor spreading with a record of this
Plate Tectonics
the theory that earth is divided into plates that move around
tectonic boundary
the place where tectonic plates touch is known as this
fault-block boundary
NOT a type of tectonic plate boundary
collide, separate, and slide
three ways that tectonic plates can move relative to each other
convergent boundary
boundary formed when tectonic plates collide
divergent boundary
boundary formed when tectonic plates separate
transform boundary
boundary formed when tectonic plates slide past horizontally
transform boundaries
this type of boundary produces earthquakes
this happens when a rock is heated and becomes less dense
sink below the surface
this happens when rock cools and becomes more dense
gravitational energy
density changes in the asthenosphere are cause by the floor of this deep within the earth
slab pull
plate motion due to higher densities
ridge push
plate motion due to gravity
plate motion due to the heating and cooling of rocks
centimeters per year
this is how fast tectonic plates move
global positioning system
this is what scientists use to measure the rate of tectonic plate movement
tension, compression
two types of stress that can be applied to the rock
mountains ranges
these are formed at convergent boundaries when compression occurs
this happens at divergent boundaries
upward arches (frowny)
downward arches (smiley)
the rock folds so that both ends are horizontal
hanging wall
a fault block that you would "hang from"
strike slip fault
can form folded, fault block and volcanic mountains
folded mountains
the highest mountains in the world; they form at convergent boundaries where continents have collided
Mariano Trench
the deepest known place on earth; approx. 7 miles deeper than sea level
where the tectonic plates touch
convergent, divergent and transform
types of boundaries