Chapter 9 Flashcards
How do igneous rocks form?
Igneous rocks are formed when magma cools.
What is the difference between extrusive and intrusive igneous rocks?
Intrusive rocks are formed under the Earth’s crust by the cooling of magma. Extrusive rocks are formed on the surface by the cooling of lava
What is the difference between magma and lava?
Magma is composed of molten rock and is stored in the Earht’s crust. Lava is magma that reaches the surface of Earth through a volcano vent.
What are sedimentary rocks?
Sedimentary rocks are rocks which have layers. The top layers are the newer layers compared to the bottom layers.
What is a metamorphic rock?
A metamorphic rock is a result of a transformation of a pre-existing rock. The original rock is exposed to very high heat and pressure which causes physical and/or chemical changes. Metamorphic rocks include marble, slate, gneiss and schist.
How does the cooling rate affect crystal size?
If the rock takes longer to cool, the crystals will have more time to develop and get larger. If it cools quickly the crystals will not be as big because it had less time to form while the rock was cooling.
How are do sedimentary rocks form?
They form when a sediment (matter that settles to the bottom of a liquid) is deposited out of air, ice, wind, gravity or water flows carrying particles in suspension. This sediment is often formed when weathering and erosion break down a rock into loose material in a source area. The water clumps the sediments together to form a sedimentary rock.
Explain the role of water in the formation of sedimentary rocks
Water clumps the sediments together in order to form a sedimentary rock.
What does heat and pressure do to metamorphic rocks?
Heat changes the chemical features of minerals and it turns into a different rock.
Identify the rock cycle
The rock cycle is a cycle where a rock can change into another rock with a certain method.
Igneous > Metamorphic (heat and pressure)
Igneous > Sedimentary (weathering and erosion)
Sedimentary > Igneous (Remelting)
Sedimentary > Metamorphic (Heat and pressure)
Metamorphic > Igneous (Remelting)
Metamorphic > Sedimentary (Weathering and erosion)
Identify the use of igneous, sedimentary and metamorphic rocks.
Igneous rocks are used in construction because of their durability.
Sedimentary rocks are used for the manufacture of paper, petrochemicals, insecticides, linoleum, fiberglass, glass, etc.
Metamorphic rock can be used for artwork, decorative items or statues. Marble is a metamorphic rock and it is used in statues and decorative items.
Explain how layers of sedimentary and other rocks, together with fossils, reveal information about past evironments and life on Earth.
Some layers have fossils or fossil traces which do reveal information about the past. Also if something is near the rock then that object/fossil can be from a similar time.
What is the most common mineral?
Quartz
What are all rocks made from?
Minerals
Why is Pumice light?
Because it has lots of holes
