Name:
Block:
Date:
The Geosphere
Environmental Science
The Earth as a System
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The Earth is divided into 4 parts:
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______________________ (rock)
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______________________ (air)
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______________________ (water)
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______________________ (living things)
Discovering the Earth’s interior
•
Scientists use ______________________ waves
• Same waves that travel through the Earth during an
earthquake
• Altered by that nature of the material through which it
travels
•
______________________ measure changes in the
______________________ & ______________________ of the waves
The Composition of the Earth
•
•
Earth is divided into 3 layers
•
______________________
•
______________________
• ______________________
Layers get progressively ______________________ towards the center of the
Earth
Crust
• Outermost layer
• Solid
•
______________________ layer
•
Makes up less than ________% of the Earth’s mass
•
5 km – 8 km think beneath ______________________
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20 km – 70 km thick beneath ______________________
Mantle
• ______________________
•
•
Between the ______________________ & ______________________
Medium density
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Makes up ________% of the mass of the Earth
Core
•
•
•
______________________ part of Earth
Located below the ______________________
Composed of the densest elements
The Structure of the Earth
•
Earth can be divided into 5 layers based on physical
properties of the layers
•
______________________
•
______________________
•
______________________
•
______________________
•
______________________
______________________ – solid, outer layer
• Crust & upper mantle
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Divided into ______________________ plates
______________________ – solid, plastic layer of the mantle
•
Made of ______________________ rock that flows & allows tectonic plates to move
______________________ – lower part of mantle
______________________ core – dense liquid layer
______________________ core – made of mostly ______________________ & ______________________
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Temperature estimated to be ______________________ -______________________ °C
•
Solid because under enormous ______________________
Both the inner core & outer core make up about ________ of the Earth’s mass
Plate Tectonics
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Tectonic plates – blocks of ______________________ that glide across the
underlying ______________________
•
Consist of the ______________________ & outermost part of
______________________
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______________________ are located on plates & move around with them
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Plates may ______________________, ______________________, or ______________________ past one another
causing mountain formations, earthquakes, or volcanoes
Earthquakes
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______________________ – break in the Earth’s crust
•
______________________ caused when rocks under stress suddenly break
along a fault causing ground vibrations
• Many cannot be felt
Majority take place at or near ______________________ plate boundaries
• Caused by stresses generated when plates separate, collide, or
slip past each other
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Magnitude
• Magnitude – measure of the ______________________ released by an earthquake
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Smallest magnitude that can be felt = ________
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Largest magnitude recorded = ________
•
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>________ magnitude = widespread damage
Increase in magnitude by a whole number means __________x more energy released than the
number below it
Earthquake Hazard
• Earthquakes cannot be predicted, but an area’s earthquake-______________________ level can be
determined by past & present seismic activity
• Earthquake-resistant buildings are slightly ______________________ so that they can sway with ground
motion
• Prevents ______________________
Volcanoes
•
Volcano – mountain built from ______________________ (melted rock) that
rises from the Earth’s interior
Located near fault lines where plates are either ______________________ or
•
______________________
Most volcanoes on land surround the ______________________ Ocean in the
•
____________________________________________
Effects of Volcanoes
• Clouds of hot ______________________, ______________________, & ______________________ can flow down a
volcano at speeds up to ____________ km/hr
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Volcanic ash can mix with water & produce ______________________
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Ash can cause ______________________ buildings, buried ______________________, damaged
______________________, & ______________________ difficulties
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Major volcanic eruptions can change ______________________
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Volcanic ash & sulfur can reduce the amount of ______________________ that reaches the Earth’s
surface, lowering surface ______________________
Erosion
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Erosion – materials of the Earth’s surface are ______________________, ______________________, or
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______________________ away & transported to another place by natural forces (wind, water, ice,
gravity)
Wears down rocks & makes them ______________________ over time
Water Erosion
• Erosion by ______________________ & ______________________
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Waves can erode ______________________
Wind Erosion
• Wind can blow soil away quickly in places where few
______________________ grow
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Soft rocks (______________________) erode more easily than hard
rocks (______________________)