Chapter 2

a collection of one or more minerals

A collection of one or more elements (atoms).

a granite <rock> is made of quartz +feldspar + biotite <minerals>. quartz <a mineral> = silicon + oxygen

An atom is the smallest piece of matter that exists with unique chemical properties

An element describes different types of atoms

There are 112 known elements, but only 92 are naturally occurring.

• Atom loses an electron from its outer shell to another atom. Ex:Halite
• 1

electrons are shared, rather than exchanged between two atoms. Ex: Quartz

atoms share clouds of electrons. Electrons in the outer shells drift from one atom to another as a result of close packing of the atoms. Ex:Gold

a weak secondary bond between electrically neutral molecules (each have a + and - end). Ex:Graphite

• Silicate mineral
• Carbonate mineral
• Sulfate minerals
• Halide minerals
• Oxide minerals
• Sulfide minerals

Has a silicate tetrahedron (SiO₄) as the basic chemical property. Silicates are the dominant group in igneous, sedimentary, and metamorphic rocks.

Have Ca, Mg, Fe (and others) attached to a carbonate ion (CO₃^-). They typically form in water and are important sedimentary rocks.

Have Ca (and other) calcium ions attached to a sulfate ion (SO₄^-2). Most rock-forming sulfate minerals, such as gypsum and anhydrite, occur in due to evaporation (sedimentary).

Have positive ions (Na, K) attached to negative ions (Cl, Br). Most rock-forming halides occur due to evaporation (salts) in sedimentary rocks.

Have metallic ions combined with oxygen. Usually economic minerals. Occur in igneous, sedimentary, and metamorphic rocks.

Have metallic ions combined with sulfur. They occur in igneous, sedimentary, and metamorphic rocks.

• Crystallization of magma (IGNEOUS)
• Deposition of particles weathered and eroded from preexisting rocks (SEDIMENTARY)
• Biologic precipitation (BIOMINERALIZATION)
• Alteration of preexisting rocks(METAMORPHISM) Biomineralization in commenly considered a sed. process

Unconsolidated particles of rock that have been transported by agents of erosion and unconsolidated particles formed as skeletal material through biominralization

A rock, usually layerd, formed from sediments and from minerals precipitated under aqueous conditions

Rock whose original mineralogy or texture has been transformed though any combination of heat, pressure, chemical environment (inc. hydrothermal fluids), and shearing stress.

Rx. organized according to their texture or fabric (size of grains or crystals, their packaging, etc.) and their compsition (quartz, feldspar, mica, clay, calcite, etc.)

system or classification according to origin

Ig. rx. usually coarsely crystalline (phaneritic), that resulted from the cooling and solidification of magma within Earth's crust. Ex:Granite, Diorite, Gabbro

Ig.rx. usually finely crystalline (aphenitic), that resulted from cooling and solidification of magma erupted onto Earth's surface. Ex: Rhyolite, Andesite, Basalt

• Rhyolite is formed of tuff-fine volcanic ash mixed with larger particles called lapilli.
• Another term for ext.rx. is pyroclastic, refers to rx. formed by violent ejection of broken rock fragments from a volcano

forms when lava cools and solidifies rapidly.It is an amorphous or noncrystalline solid, aka mineraloid

Quartz, feldspar, mica, amphibole, pyroxene, and olivine.

• Light colored ig.rx.
• dominated by Quartz, feldspar, and muscovite (potassium rich)mica. Ex. Granite & ryholite. form much of the continental crust

• Dark colored ig.rx.
• dominated by biotite (a ferromagnesian, or Fe- and Mg- bearing) mica, amphibole, and pyroxene.
• Mafic- basalt and gabbro
• Ultramafic- peridotite

• midway between felsic and mafic
• Ex: andesite, diorite

An ig. rock body

An irregularly shaped intrusive (plutonic) ig. rock body larger then 100 km² and no known base.

An irregularly shaped intrusive (plutonic) ig. rock body smaller then 100 km².

Unusually large crystals. Often containing desirable and rare elements as Be, B, and Li

Thin, tabular, sheet-like intrusive body that cuts across the layering or fabric of preexisting rocks.

a tabular, sheet-like intrusion that extends parallel to the layering or fabric of the rocks it intrudes.

extends parallel to the layering or fabric of preexisting rocks, but when it was emplaced, it caused the intruded rocks to bend upward into a dome.

The process involving in changing sediments to rock.

the precursors of sed.rx., are particles (or clasts) composed of silicate minerals (notebly quartz, mica, and feldspar).