35 terms

Matthew - Science Ch 8 Changes on Earth - 3rd Grade


Terms in this set (...)

How many layers is the earth divided into?
What is the crust?
outer layer of the earth made of different kinds of rock
What is the Mantle?
Middle layer of the earth
What is the mantle made of?
Hot igneous and metamorphic rock
What is the core?
Inner most layer of the eart
What is the earth's core made of?
What are landforms
natural features on the surfaced of the earth's crust
What is a glacier
large moving body of ice
where do glaciers form
cold places where snow and ice pile up over years
what is a valley
low narrow area on earth's crust
how do valleys form
by rivers and glaciers
what is a plateau
plain that is higher than the land around it
what is a mountain
high land above land around it
How are mountains formed
when blocks of rocks are pushed up or drop down along cracks
how do lakes form
when flow of water slows enough to fill an area
what are volcanoes
opening in the earth's crust from which hot melted material errupts
where do volcanoes form
deep in mantle
what are eruption materials
ash, cinders, hot molten rock (lava)
what does lave turn into
igneous rock - makes new crust
What are earthquakes?
shaking of earth's crust
why do earthquakes happen
sudden shift between parts of earth's crust.
where do earthquakes occur most often
faults or cracks in crust
what do earthquakes do to the land
the vibrations cause cracks and piles of rubble; damage building; cause landslides
what is weathering
process that changes rock by breaking into smaller pieces
plants and weathering
roots grow in cracks and split
water and weathering
changes minerals in rock, weakens and begins to break apart
ice and weathering
water gets into cracks, freezes, and expands so pushes on sides
what is erosion
the movement of weathered materials
rainwater and erosion
rainwater carries soil away
ocean waves and erosion
erodes coast
rivers and erosion
carry bits of rock
wind and erosion
carries sand and dry soil
gravity and erosion
pulls rock and soil downhill
squirrels and erosion
tunnel and water/air move through
worms or ants and erosion
move soil and water/air move through