Atom
Smallest individual particle retaining properties of an element
Element
Fundamental substances into which matter can be broken down chemically
Mineral
Naturally formed inorganic solid that has a specific chemical composition and a distinct crystal structure; composed of elements
Rock
Naturally formed, coherent mass of one or more minerals, sometimes including organic debris
What characteristics does a mineral have?
1) Naturally formed; 2) inorganic; 3) solid; 4) specific chemical composition 5; ) characteristic crystal structure
Mineraloids
Lack specific composition and/or characteristic crystal structure
What is a nucleus?
It is the central part of an atom that is made of protons and neutrons and despite its small volume contains most of the mass of the atom
Atomic Number
Number of protons in nucleus
Mass Number
Total number of protons plus neutrons
Isotopes
Atoms with the same atomic number but different mass numbers
Electrons
Contribute very little mass; move around nucleus in complex
3-D patterns called orbitals; energy-level shells are groupings of orbitals
Ion
Atom with excess positive or negative charge caused by electron transfer
What charge does a Cation have?
Positive
What charge does a anion have?
Negative
Compounds
Atoms of two or more elements combined in a specific ratio
Molecule
the smallest unit
What are the different types of bonds?
Ionic, Covalent, Metallic, and van der Waals
Ionic
Electrostatic attraction between + & - charged particles
Covalent
The strongest of the bonds that occurs when atoms share electrons
Metallic
Closely packed atoms; electrons shared between several atoms
van der Waals
Weak secondary attraction between certain molecules
Complex ions
Two or more ions that act as a single entity
Crystal Structure
geometric patterns of atoms in a solid
Crystalline
Has a crystal structure
Amorphous
Lack Crystal structure
Ionic Substitution
Ions with similar sizes and charges can substitute for each other
Mineral Group
Displays extensive ionic substitution w/o changing cation:anion ratio
Crystal form (and growth habit)
Geometric arrangement of crystal faces
Polymorphs
2+ minerals w/ same composition but different crystal structures
What are the different properties of minerals?
cleavage, luster, color, streak, hardness, density, and specific gravity
Cleavage
Mineral's tendency to break in preferred directions along planar surfaces
Luster
Quality and intensity of light reflected from a mineral
Color
Often striking, but unreliable means of identification
Streak
Thin layer of powdered mineral made by rubbing it on non-glazed porcelain
Hardness
Mineral's relative resistance to scratching
Mohs hardness scale
(I) talc, (2) gypsum, (3) calcite, (4) fluorite, (5) apatite,
(6) orthoclase (feldspar), (7) quartz, (8) topaz, (9) corundum and (10) diamond
Density
mass/unit volume
specific gravity
ratio of mass of substance to mass of equal volume of water
What are the 12 most abundant elements?
O,Si,AI,Fe,Ca,Mg,Na,K,Ti,H,Mn & P
What parcentage of the earths crust do the 12 most abundant elements make?
(99.23% of crust)
Silicates
Minerals that contain silicate anion (Si0,), they are also the most abundant group
Silicate Tetrahedron
Four oxygen atoms (large) surrounding silicon atom (small);
oxygen atoms must: (1) bond with other cations and/or
(2) bond with two silicon atoms at one time
Polymerization
Process of linking silicate tetrahedra
What are the common minerals?
Olivine group, Garnet group, Pyroxene group, Amphibole group, Micas, Quartz, Feldspar group, Carbonates, Phosphates, and Sulfates
What are the Ore Mineral Groups?
Sulfides and oxides
Olivine group
Isolated silicate tetrahedra; (Mg,Fe),SiO,; distinctive green color
Garnet group
Isolated tetrahedra; A3B,(SiO4),, A=Mg,~e,',ca,Mn, & B=AI,F~,',C~
Pyroxene group
Single chains of tetrahedra; AB(SiO,),; augite most common
Amphibole group
Double chains; A,B,(Si,O,,),(OH),; hornblende most common
Micas (clays, chlorites & serpentines)
Sheets; (Si401,)4-; muscovite & biotite (micas)
Quartz
1 5% of crust; SiO,; chalcedony (cryptocrystalline) precipitated from water
Feldspar group
60% of crust; AI(l,,Si(3.2,0,; K-feldspar & plagioclase (Na & Ca)
Carbonates
Calcite, aragonite, dolomite
Phosphates
Apatite
Sulfates
Gypsum, anhydrite
Sulfides
Pyrite, galena, sphalerite, chalcopyrite (ore minerals)
Oxides
Magnetite, hematite (ore minerals)
What are the types of rocks?
Igneous, Metamorphic, and Sedimentary
Igneous Rocks
Form from cooling and solidification of magma
Sedimentary
Form from consolidation of sediment (Made from any other rocks)
Metamorphic
Original form has been altered by high To and/or P
What is the Rock Cycle?
Exposed rocks are transformed into sediment; sediment is buried
and compacted, becoming sedimentary rock; deeper burial turns it
into metamorphic rock, and even deeper burial may cause rock to
melt, forming magma from which igneous rock will form.
Uplift=
What is rock texture?
size, shape and arrangement of mineral grains
mineral assemblage
varieties and abundances of minerals present
What are the 2 types of igneous rocks?
Extrusive, and Intrusive
Extrusive (volcanic)
Formed by solidification of lava and/or tephra on earth's surface. Formed on the Earth surface.
Intrusive (plutonic)
Formed by solidification of magma within earth's crust.
Texture
Size and packing of mineral grains (Both intrusive and extrusive have the same type of ingredients but have different texture)
What are the sizes of rocks?
Intrusive, Phanerite, Pegmatite, Aphanite, Pophyry, and Glassy
lntrusive
Coarse grained (slow cooling)
Phanerite
Coarse grained (>2mm) (intrusive)
Pegmatite
Unusually large mineral grains (>2cm)
Aphanite
Fine grained (<2mm) (extrusive)
Pophyry
Coarse grains (phenocrysts) in a fine-grained groundmass,
Glassy
Cools so quickly that atoms aren't able to organize into minerals.
What is an example of glassy rock?
Obsidian
Mineral Assemblage
Along with texture, determines names of igneous rocks.
What are 3 intrusive igneous rocks?
Granite, Diorite and Gabbro
Granite
Contains quarts, potasiumfeldspare, sodium, micas, amphibole and is the most common intusive rock
Diorite
Intusive rock does not contain quarts and is a lot less common than granite
Gabbro
Very rare Intrusive rock
3 extrusive igneous rock
Rhyolite, Andesite, Basalt
Rhyolite
Aphanitic equivalent of granite; pale; quartz & feldspar phenocrysts; rare. High in silica
Andesite
Aphanitic equivalent of diorite; darker; plagioclase & amphibole/pyroxene phenocrysts; more common. Named after the Andes mountain range.
Basalt
Aphanitic equivalent of gabbro; dark gray or black; plagioclase & pyroxenelolivine phenocrysts; most common. No Quarts usually olivine.
Pyroclast
Fragment of rock ejected during volcanic eruption
Pyro
fire
Clast
many bits
Pyroclastic rocks
Formed from pyroclasts
Tephra
Deposit of pyroclasts; includes bombs (>64mm), lapilli (2-64mm), and ash (<2mm). Based on size.
bombs =>lapilli =>ash
Ash
A powdered volcanic glass.
Agglomerate
Coarse (bomb-sized) tephra particles
Tuff
Fine (lapilli- to ash-sized) tephra particles
Welded tuff
Glassy; produced when individual hot ash particles fuse. Glassy shards of ask weld together. Pompeii
Plutons
All bodies of intrusive igneous rock, regardless of size or shape.
What are the minor plutons?
Dike, Sills, Laccolith, and Volcanic pipe
Dike
Tabular, sheet-like body that cuts across layering of rock it intrudes
What is an example of a dike?
The Black Dike on Mount Morand in the grand Tetons.
Sills
Tabular, sheet-like bodies that are parallel to layering of rock they intrude
Laccolith
Parallel to layering of rock, but has bent layers above it into a dome
What is an example of a Laccolith
The Hennery Moutains
Volcanic pipe
Cylindrical conduit that fed magma to vent; if erosion strips away surrounding rock, rock that filled pipe is a volcanic neck
What is an example of a volcanic neck? and how was it formed?
Ship rock in new Mexico is a volcanic neck (formed by the volcano eroding away but leaving the volcanic pipe)
What are the Major Plutons?
Batholith, Stoping, Xenolith, and Stock
Batholith
Large, irregularly-shaped pluton that cuts across layering of rock and are the largest intrusive bodies. They are formed when large magma chambers move to the surface.
What is an example of a Batholith?
The Idaho Batholiths in Yosemite national park.
Stoping
Rising magma body dislodges fragments of overlying rock. When country rock falls into the batholith as it moves to the surface.
Xenolith
Stoped fragment enclosed in magmatic body when it solidifies. It is the result of Stoping.
Stock
Irregularly-shaped plutons, like batholiths, but smaller
What is an example of a stock?
Big Cottonwood Canyon
Magmatic Differentiation by Fractional Crystallization
Compositional changes caused by sinking of early crystallized minerals to bottom of magma chamber (Isn't how it usually work)
Bowen's Reaction Series
Sequence in which minerals crystallize from cooling magma; minerals with highest melting points crystallize first.
Continuous Reaction Series
Makes Ca-rich plagioclase then when it runs out of Ca it starts using Na and making Na-rich plagioclase.
Discontinuous reaction series
Olivine -> Pyroxene -> Amphibole -> Biotite
Late stage
K-spar (and/or muscovite if water pressure is high); excess SiO2, will crystallize as quartz (not a reaction series.
Magma
Molten rock, together with any suspended mineral grains and dissolved gases, that forms by melting of rock in crust and mantle.
Volcano
Vent from which magma, solid rock debris, and gases are erupted
Lava
Magma that reaches earth's surface
What is a predominant ingredient in Magma?
SiO, always predominant; characterized by high To; has ability to flow
What is the most common gas in Magma?
Water
What is the composition of Basaltic Magma?
-50% SiO
What is the composition of Andesitic Magma? ;
-60% SiO
What is the composition of Rhyolitic Magma?
-70%
Viscosity
a liquid's resistance to flow.
What does the viscosity depend on?
It Depends on temperature and composition.
Pahoehoe
Smooth, ropy-surfaced lava formed from very hot, fluid lava
Aa
Rubbly, rough-looking lava formed from cooler, very viscous lava
Eruption of Magma
Lower density causes magma to slowly rise; as pressure decreases, gas comes out of solution (exsolves)
Nonexplosive Eruption
Low-viscosity (basaltic) magma and low dissolved-gas content
What are the nonexplosive eruptions of a volcano?
lava fountain, spatter cone, lava tube, vesicles, amygdules
Lava fountain Eruption
Forms when basaltic magma rises so rapidly that gas bubbles from solution
Spatter cone
Forms when bits of falling lava pile up beside vent
Lava tube
Subsurface channels in pahoehoe lava flows
Vesicles
Gas bubble holes preserved in solidified rock; produces rock w/vesicular texture
Amygdules
Vesicles filled by secondary minerals
Explosive
Viscous (andesimtic/rhyoliticm)magma with high dissolved-gas content
What are examples of Explosive Eruptions?
Pumice, Ash, Eruption column, Tephra fall, Pyroclastic, lgnimbrite, and lateral blast
Pumice
Froth of innumerable, glass-walled bubbles
Ash
Tiny fragments of shattered, solidified magma
Eruption column
Mixture of hot gas and tephra rising rapidly into air
Tephra fall
Rain of debris particles as eruption cloud drifts w/upper winds
Pyroclastic flow
Denser-than-air mixture of hot gas & ash; fast & lethal
ignimbrite
Solidified deposit resulting from pyroclastic flow
Lateral blast
Sideways eruption
What are the three types of volcanos?
Shield volcanoes, Tephra cones (cinder cones), Stratovolcanoes (composite cones)
Shield volcanoes
Built up of very fluid (basaltic) lava flows; broad, dome-shaped; gentle slopes
Tephra cones (cinder cones)
Formed from pyroclastic debris around a vent; magma is gasrich; slopes typically about 30" (angle of repose)
Stratovolcanoes (composite cones)
Emit both tephra and lava; build up steep, conical mounds; much larger than tephra cones
Crater
Depressions near summit from which volcanic materials are ejected
Lava domes
Late-stage, very viscous lava extruded after most gas exsolved
Calderas
Circular, steep-walled basins >kIm in diameter near summit
Resurgent domes
Due to uplift of caldera; also small tephra conesllava flows
Diatremes
Volcanic pipes filled w/ rubble of broken rock