Chapter 20: Earth Materials

Clast Size

________ also provides clues to help determine the depositional environment of the sediment that formed the detrital rock.

Mineral

________: a naturally occurring element or compound that is inorganic, solid, and has a crystalline structure.

Non-Silicate Groups

The ________ are a source of many valuable ore minerals and building materials.

Minerals

________ can be classified using six basic crystal forms.

Cementation

________: When minerals slowly precipitate out of water and fill spaces between clasts.

Texture

________: describes the size, shape, and arrangement of the rocks.

Silica

________ is a common term for a compound that contains silicon plus oxygen or silicon dioxide (SiO2)

compaction

The process by which clasts stick together by being pushed together is called ________.

Coal

________ usually develops from peat, a brown, lightweight deposit of moss and other plant matter.

crystals

The types of atoms that are added depend on the atoms in the growing ________ surroundings.

Fine

________- grained, extrusive igneous rocks often have grain sizes that are too small to be seen without magnification.

atomic arrangement

The ________ and composition of minerals allow them to be sorted into groups.

Sand

In order of decreasing size, clasts are classified as gravel, ________, silt, or clay.

Metamorphic rocks

________ can be classified by their texture.

Mechanical Weathering

________ occurs when physical forces break rocks into smaller clasts.

Mineral crystals

________ can form in different ways.

Bowens reaction series

The ________, shown below, illustrates the sequence in which minerals crystallize from magma at different temperatures.

Inorganic

________ means that minerals are materials that are not produced by living organisms.

Igneous

Any ________, sedimentary, or metamorphic rock can be changed through metamorphism.

Feldspar

________ is an example of a mineral with two planes of cleavage.

orderly internal arrangement of atoms

The ________ in a mineral often is related to its external crystal shape.

Coarse

________- grained granite and fine- grained rhyolite both form from granitic magmas.

Regional

________ and contact metamorphism cause changes that can occur over millions of years.

Detrital Sedimentary Rock Composition

________ depends on sources of rock material that were eroded, transported, and eventually deposited.

Mineral composition

________ is extremely variable, so adjectives are used to modify the general name of the rock.

Clay Minerals

________, micas, and amphiboles are examples of minerals that contain water in their crystal structures.

Sharp folds

________ sometimes display intense transformations in metamorphic rocks.

Mineral Grains

________ are randomly oriented when no directed force is involved.

Metamorphic Changes

________ in rocks are caused by thermal energy, pressure, and chemical reactions.

Crust

The ________ is the outermost layer of Earth.

Streak Test

A(n) ________ is performed by rubbing a mineral on an unglazed, white porcelain tile.

Hardness

________: The physical property that measures resistance to scratching.

Composition of Minerals

The ________ are indicated by their chemical formulas.

Metamorphic Processes

________ produce rocks with different textures.

Igneous Rocks

________ are those that form from molten magma.

Metamorphic Textures

________ can also be nonfoliated where crystals are in more random orientations.

Rock-Making Process

The ________ is a continuous cycle.

Continental Material

It includes all ________ and the material that forms the ocean bottom.

Mineral

a naturally occurring element or compound that is inorganic, solid, and has a crystalline structure

Cleavage

The ability of a mineral to do this is the physical property

Fracture

When a mineral breaks unevenly

Hardness

The physical property that measures resistance to scratching

Streak

The color of a mineral in powdered form

Magma

Molten rock material found inside Earth

Non

metallic minerals are valuable as well

Rock

a naturally formed mixture containing minerals, rock fragments, or volcanic glass bound together

Texture

describes the size, shape, and arrangement of the rocks

Intrusive Igneous Rocks

form within, or push into, regions of Earths crust

Extrusive Igneous Rocks

rocks that form from lava erupted at Earths surface

Coarse-grained gabbro and fine

grained basalt both form from basaltic magmas

Clasts

small bits and pieces

Pore Space

The empty space between clasts

Cementation

When minerals slowly precipitate out of water and fill spaces between clasts

Foliated

crystals are arranged in layers and bands

Rock Cycle

The continual changing of rocks into different types