Download molten rock

Rocks, Rocks, and More
Rocks
Types of Rocks
• Igneous rock
Pumice
– Forms when magma cools and hardens
– Can form underground or above ground
– Types of igneous rock:
•
•
•
•
Granite
Scoria
Pumice
Obsidian
Obsidian
Scoria
Types of Rocks
• Wind and water can break igneous rock into
sediments.
Igneous
Rock
Sediments
Wind and
Water
Cementation
Sedimentary
Rock
• When the sediments are cemented into a layer
over time, igneous rock becomes sedimentary
rock.
• What causes the cementation?
Types of Rocks
• Sedimentary Rock
– Common types include chalk, limestone, and
clay
– Often contains fossils
– Types of Sedimentary rocks
• Clastic: made up of different rock fragments
• Biogenic: contain materials from organisms such
as corals
• Precipitate: rocks formed when water evaporates
such as halite (rock salt left behind after sea water
evaporates)
Types of Rocks
• Weathering and erosion will revert
sedimentary rocks back to sediments.
• Heat and pressure change sedimentary
rock to metamorphic rock.
Sediments
Weathering
and Erosion
Sedimentary
Rock
Heat and
Pressure
Metamorphic
Rock
Types of Rocks
• Metamorphic Rock
– Make up a large part of the Earth’s crust
– Common examples include slate, shale, and
mudstone
– Can go through foliation, a process where the
randomly distributed minerals in the rock
become organized in a parallel manner
– Foliation can cause cleavage or breakage of
the rock at weak cracks
Foliation
The disorganized minerals become more
organized.
Cleavage
Weak areas are prone to breakage.
Types of Rocks
• Very high heat melts metamorphic rock
into magma.
• Weathering and erosion will change
metamorphic rock back to sediments.
Sediments
Weathering
and
Erosion
Metamorphic
Rock
Magma
Melting
Magma (molten rock)
• A hot liquid made of melted minerals
• Called lava when it appears on Earth’s
surface, usually from volcanic vents
• The temperature of magma can range
from 650 to 1200 °C
• Created by heating rock under extreme
temperatures
• Cooling magma creates
igneous rock
Rock Cycle
Igneous
Rock
Cooling
Magma
Melting
What
do
What
does
melting
What
do
do does
heat
What
doand
cooling
Which
rock
becomes
What
the
weathering
and
metamorphic
rock
compaction
and
pressure
to
do
weathering
and
magma
create?
metamorphic
rock
melting
of
igneous
erosion
do
create?
cementation
doall
to
sedimentary
rock?
erosion
do to
to
this
under
heat
and
rock
create?
types
of
sediments?
type
of rock?
rock?
pressure?
Metamorphic
Rock
Heat and
Pressure
Weathering
and Erosion
Sediments
Cementation
Sedimentary
Rock
Minerals
• Rocks are made up of one or more types
of minerals.
• True minerals have the following
characteristics:
– Solid
– Have a crystal structure
– Inorganic and naturally occuring
– Defined chemical composition
Minerals
• Ways to classify minerals:
– Hardness: how hard the material is
– Luster: how the surface interacts with light
– Metallic: metallic qualities such as
reflectivity
– Color: what color the material is
– Magnetism: the rock’s ability to attract other
metals
– Fluorescence: appearance under UV light
Erosion
• Erosion is the movement of particles by
wind, water, ice, or gravity.
• Erosion is a natural process that can be
increased by human land use.
• Steep slopes, lack of vegetation, and land
use can increase the rate of erosion.
• How does erosion differ from weathering?
Erosion
Erosion
• Types of erosion include:
– Gravity erosion
– Water erosion
– Shoreline erosion
– Ice erosion
– Wind erosion
• Can you explain what occurs in each of
these types of erosion?