Earth Materials Study Set

What do igneous rocks form from?

Magma and lava

What are the characteristics of felsic igneous rocks?

Light-colored, abundant in aluminum and quartz, contain a lot of SiO2, less dense, make up the continental crust

Describe extrusive igneous rocks.

cools rapidly on or near the Earth's surface from lava, forming small to no crystals

Describe intrusive igneous rocks.

cools slowly beneath the Earth's surface in magma chambers, forming large crystals

What are two examples of non-foliated metamorphic rocks?

quartzite and marble

What are four examples of foliated metamorphic rocks?

slate, gneiss, phyllite, schist

What is a porphyroblast?

A large mineral crystal in a metamorphic rock that grew within the finer-grained rock.

What is the definition of a rock?

A rock is a generally hard, natural substance made up of minerals.

How do geologists classify metamorphic rocks?

According to their texture and arrangement of minerals.

What is the make-up of all solid matter on Earth from the smallest-largest?

Atoms, Elements, Compounds, Minerals, Rocks

How are igneous rocks classified?

By their texture and mineral content

What are the four ways to describe texture in igneous rocks?

Coarse-grained, fine-grained, glassy, porphyritic

What are the unique physical properties of minerals?

Color, Streak, Hardness, Luster, Cleavage/Fracture, Crystalline Structure, Density

How do conglomerates and breccias differ?

Conglomerates have rounded fragments; breccias have angled fragments.

How does metamorphism occur in the Earth's crust?

Contact and regional

What are the categories of metamorphic rocks?

Foliated and non-foliated

What are the characteristics of mafic igneous rocks?

Dark-colored, abundant in iron and magnesium, very little SiO2, very dense, make up oceanic crust

Describe non-foliated metamorphic rocks.

Do not show bands, very uniform in color

What are the main tools used for measuring hardness?

Fingernail, piece of copper, iron nail, glass, steel file, streak plate

How do clastic sedimentary rocks form?

From lithification of clastic sediments.

What metamorphic rock forms from granite?

Gneiss

How do rocks form metamorphic rocks in the rock cycle?

Heat and pressure

What are the three basic categories of rock?

Igneous, Sedimentary, Metamorphic

What are some uses of foliated metamorphic rock?

Landscaping, roof shingles

Describe regional metamorphism.

Larger in scale, caused by pressure.

What metamorphic rock does limestone become?

Marble

How do rocks form igneous rocks in the rock cycle?

Melting and cooling

Describe glassy igneous rock texture.

No crystals; may have holes due to rapid cooling

What are the two most prominent elements in the Earth's crust?

Oxygen and Silicon

What are the four sub-categories of clastic sedimentary rocks?

Pebble and larger, sand-sized, silt-sized, clay-sized

How do chemical sedimentary rocks form?

Precipitation of dissolved minerals from water

What affects the crystal structure of minerals?

Pressure

What metamorphic rock forms from sandstone?

Quartzite

What are some uses of non-foliated metamorphic rock?

Sculptures, architecture

What is the order of the metamorphic rocks originating from shale? (Clue: one forms from the metamorphic rock before it due to extreme heat and pressure)

Shale-Slate-Schist

Describe foliated metamorphic rocks.

Show banding under pressure

What are the two main groups of minerals?

Silicates and non-silicates

Describe contact metamorphism.

Smaller in scale, related to heating

What are five features of sedimentary rocks?

Stratification, cross beds and grading, ripple patterns, mud cracks, fossils

What is the basic concept of the rock cycle?

That all rocks are formed from rocks already existing.

How do organic sedimentary rocks form?

The accumulation and lithification of remains of once-living things.

What is metamorphism?

The process by which heat, pressure, or chemical processes change one type of rock to another

How does temperature and pressure change inside the Earth?

They increase with depth.

How do rocks form sedimentary rocks in the rock cycle? (in order of process)

Weathering, erosion, deposition, cementation, and then compaction

Can chemical sedimentary rocks be single minerals? (Y/N)

Yes

Can the same type of rock form itself? (ex. igneous-igneous) (Y/N)

Yes

Do metamorphic rocks retain some characteristics of their parent rocks? (Y/N)

Yes

Describe porphyritic igneous rock texture.

both large and small crystals, starting as magma and becoming lava.

What are the three types of sedimentary rocks?

clastic, chemical, organic

How do sedimentary rocks form?

compaction and cementation

Describe course-grained igneous rock texture.

large, visible minerals

What is the scientific, geological definition of a mineral?

naturally-occuring, inorganic, solid with a crystalline structure, has a definite chemical composition, has unique physical properties

Describe fine-grained igneous rock texture.

sand-sized crystals or smaller