Vocab
What is sediment?
Sediment is tiny pieces of rock formed by weathering and erosion.
break down rocks into sediment
Weathering & Erosion
What is the relationship between minerals and rocks?
Minerals combine to form rocks.
Sedimentary rock layers normally form with the _(1)_ rock closest to the surface and the _(2)_ rock farthest from the surface.
Sedimentary rock layers normally form with the youngest rock closest to the surface and the oldest rock farthest from the surface
What can hardness tell you about a mineral to help you to identify it?
Hardness: indicates how hard the mineral is (on the Moh’s Scale) compared with other minerals – diamond is the hardest and talc is the softest
What do the words intrusive and extrusive mean?
Intrusive means igneous rock that cools inside the Earth (interior). Extrusive means igneous rock that cools outside the Earth (exterior).
high temperature and high pressure transforms rocks into metamorphic rock
Heat and Pressure
Explain how intrusive and extrusive igneous rocks differ in their crystal sizes.
Intrusive rocks have larger crystals because they take longer to cool in the Earth.
Extrusive rocks have very tiny or no crystals (in the case of obsidian) because they cool so quickly.
What is foliation in metamorphic rocks?
Foliation in metamorphic rocks is repetitive visible lines where similar minerals line up from the pressure during metamorphosis.
What can cleavage and fracture tell you about a mineral to help you to identify it?
Cleavage: refers to the property when a mineral breaks in flat planes or sheets
Fracture: refers to the property when a mineral breaks with rough/jagged edges
What is the difference between lava and magma?
Magma is molten rock inside the Earth and lava is molten rock outside of the Earth.
minerals get squeezed and ‘glued’ together into a sedimentary rock
Compaction and Cementation
What is the rock cycle?
The Rock Cycle is the series of processes that create and transform the types of rock into other types of rock.
Explain how intrusive and extrusive igneous rocks differ in their crystal sizes.
Intrusive rocks have larger crystals because they take longer to cool in the Earth.
Extrusive rocks have very tiny or no crystals (in the case of obsidian) because they cool so quickly.
Why would you need to run several tests on a mineral to correctly identify it?
Minerals have similar physical properties to one another, so you have to run several tests in order to distinguish some minerals.
What do the words naturally occurring and inorganic mean? (These are two different things!)
Naturally occurring means that the substance is NOT man-made.
Inorganic means the substance is NOT alive, was NEVER alive, and was NOT made by something that is or was ever alive.
Pumice and scoria are examples of extrusive igneous rock that contain holes. How did the holes get there?
Holes form in igneous rock when gasses in the magma or lava escape while the rock is cooling.
What types of rock can be changed by metamorphosis and become metamorphic rocks?
All types of rock can be changed by metamorphosis – igneous, sedimentary, and even metamorphic rocks.
What are the three types of sedimentary rocks and what are their characteristics/how are they formed?
Clastic sedimentary rocks are made up of clasts (pieces of other rocks) compacted and cemented together (example: conglomerate).
Chemical sedimentary rocks are formed when minerals precipitate out of solutions of water as the water evaporates. The minerals get cemented together (example: limestone).
Organic sedimentary rocks form from organic matter (leaves, animal material, fossils) that become compacted and cemented into a mass with minerals over time.
What characteristics must a substance have in order to be classified as a mineral?
In order to be classified as a mineral, a substance must have these characteristics:
(1) Be naturally occurring, (2) Be inorganic, (3) Be solid, (4) Have definite chemical composition, (5) Have an orderly arrangement of atoms (crystal structure).