A Rock’s JourneyFirst Steps
Igneous RocksBefore rocks, there was
◦Magma Molten crystals that flow like a liquid.
After these molten mineral grains cool, they form a specific type of rock called◦ Igneous rocks
These rocks come in three different and unique forms◦ Intrusive◦Extrusive◦Volcanic Glass
Igneous RocksIntrusive rocks
◦Form in the depths of the Earth over thousands of years
This time allows them to form very◦Large mineral grains
Igneous RocksWhen magma reaches the
surface and cools there, it forms◦Extrusive rocks
With very ◦Small ◦mineral grains
Igneous RocksThe violence of volcanoes causes
mineral grains to be thrown into the air where they cool so quickly they have◦Little or no◦Mineral grains
These rocks are called ◦Volcanic glass rocks
Igneous RocksAlthough similar in general shape
and structure, these three types have different “races” within them:◦Basaltic◦Granitic ◦Andesitic
Igneous RocksBasaltic rocks are
◦ Dense, dark-colored rocks◦ Formed from magma that contains lots of the elements
Iron and magnesium
In opposition, granitic rocks are◦ Light colored rocks ◦ With a ◦ Lower density◦ Than basaltic rocks because it contains a lot of the
compound silica (SiO2)Finally, there are those rocks which find
themselves with a bit of basaltic and a bit of granitic properties; these rocks are called◦ Andesitic
Igneous Rocks
Igneous Rocks
Metamorphic RocksOnce rocks form solid and strong,
they must face the perils of this earth. Those rocks that face the most extreme conditions of earth form brilliant rocks that are even stronger than before.
These rocks are called◦Metamorphic rocks
Metamorphic RocksThe rock that forms into the
metamorphic rock is called the ◦Parent rock
Metamorphic RocksThe same ingredient mineral
grains take on many forms depending on the amount of ◦Heat and/or pressure◦they experience
Metamorphic Rocks
Forces experienced by rocks can come from either the ◦Weight of the Earth
pressing down on the rocks◦The extreme temperature
created near the Earth’s core
◦Or the contact of the rocks with hot lava, also called magma
Metamorphic RocksThese powers force the mineral
grains to flatten and move positions
If the mineral grains form into layers, the new metamorphic rock is called a ◦Foliated rock
If, however, they move into random positions, they are called◦Non-foliated rocks
Metamorphic RocksFoliated Non
foliated
Offspring becoming Parents
How metamorphic rocks are formed
Increasing Pressure & Temp
Categorizing Metamorphic Rocks
Sedimentary RocksRocks formed when fragments of
other rocks come together to form a new rock
Sedimentary RocksThree types of Sedimentary
Rocks◦Detrital◦Chemical◦Organic
Sedimentary RocksDetrital Rocks
◦Steps of Creation 1. Rock broken
Weathering and Erosion 2. Compaction
Squeezed together 3. Cementation
Water drips between and solidifies
Sedimentary RocksClassified by size and shape
Sedimentary RockChemical Sedimentary
◦Rocks from solution
Limestone
&
Rock Salt
Sedimentary RocksOrganic sedimentary rocks
◦Made from once living material
Sedimentary RocksAs humans do, some rocks will break up
with their partners and form new bonds with new partners. These new blended families are called sedimentary rocks. They form from the broken, shattered pieces or rocks and shells, called sediment, that have been torn from their parent rocks by harsh wind and raging water. These blended families come in three very different categories: detrital, chemical, and organic.
Sedimentary RocksThe most common form is when pieces of
sediment are forced together under pressure to form detrital rocks. This process occurs in three stages. First, the rock is broken down by weathering and erosion, which is the movement of weathered materials. Second, the sediments get closer and closer through a process called compaction. Finally, new water joins the mix and solidifies the bonds through cementation. These rocks are classified by the size and shape of their sediments.
Sedimentary RocksLike people of the same race, rocks of the
same type are still vastly different from each other. Out of solution come chemical sedimentary rocks. These rocks form when pieces of sediment that were dissolved in water come together and form a solid rock. Two examples of these rocks are limestone and rock salt. The rocks that aren’t really rocks are called organic sedimentary rocks because they are made of once-living material. Two examples of these rocks are coal and chalk.
Rock CycleHow rocks recycle
Rock Cycle