Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

EOS 120 > Minerals: Earth Materials > Flashcards

Minerals: Earth Materials Flashcards

1
Q

What is the solid Earth made of?

A

Rocks like basalt, granite and sandstone make up the Earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Rocks are made of minerals. What are they?

A

the smallest homogenous units that the Earth can be physically broken into

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are Minerals made of?

A

A single element
OR
2 or more elements combined to form a chemically stable and electrically neutral compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why are minerals important?

A

the building blocks of rocks
important resources - integral to our culture since early humans, store elements necessary for life
critical to determining the history of our planet - form in very specific conditions and environments
minerals are often important evidence in crime scene investigations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

All solid Earth processes involve growth and destruction of …

A

minerals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a mineral? (definition)

A 
Naturally occurring
Inorganic (not soft parts of organisms, plants)
Ordered internal crystalline structure
Fixed chemical composition
Homogeneous solid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Graphite and Carbon are both pure carbon, so why are they so different?

A

differ in internal structure (how the C atoms are arranged)
Graphite - Sheets
Diamond - Tetrahedral formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why do different elements combine to form minerals?

A

To become stable: for atoms to have a full outermost electron shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do different elements combine to form minerals?

A

Lose electrons -> gain net positive charge (become a cation)
OR
Gain electrons -> become a negatively charged ion (anion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are ions?

A

Charged atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is an Anion?

A

Negatively charged ion - atom has gained electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a cation?

A

Positively charged ion - atom has lost electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the two types of bonding?

A

Electron transfer: ionic bonding e.g. NaCl halite

Electron sharing: covalent bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the composition of the Earth’s Crust?

A

Mostly Si and O
Remainder: Al, Mg, Na, K, Fe

Only ~20 minerals account for most of the crust:
Rock-forming minerals
Mainly silicates (Feldspars, quartz, micas, olivine, pyroxenes, amphiboles, clays)
Also carbonates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the silicate mineral groups?

A

different arrangements of silicate (SiO4) tetrahedra

each mineral group has different characteristics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an example of an isolated tetrahedra silicate mineral?

A

olivine

garnet

17
Q

What is an example of a chain silicate mineral?

A

pyroxene

18
Q

What is an example of a double chain silicate mineral?

A

amphibole

19
Q

What is an example of a sheet silicate mineral?

A

mica

20
Q

What is an example of a 3D framework silicate mineral?

A

quartz

21
Q

What is the mineral composition of olivine?

A

Mg2SiO4 or Fe2SiO4

22
Q

What is the mineral composition of quartz?

A

SiO2

23
Q

Why do minerals have colour?

A

Interaction of light with ions and their bonds
Different ionic substitutions
Chemical impurities

24
Q

what are mineral properties dictated by?

A

composition, bonding, and structure

25
Q

what are the properties of minerals?

A 
Crystal structure
Colour and streak
Lustre (metallic, nonmetallic)
Hardness: Moh's scale
Cleavage
Fracture
Specific gravity
Taste
Magnetism
Reaction with acid
26
Q

what are the requirements to make a mineral?

A
  1. Right elements/ions must be available e.g.magma, Si, O, Al,Fe,Mg, Ca, etc seawater Cl,Na,SO4, Mg, Ca, CO3 etc
  2. Right temperature e.g.olivine: highT, clay: low T
  3. Right pressure e.g. garnet: moderate T and P
27
Q

How do conditions for minerals change in the Earth?

A

Increase depth of a mineral -> enormous increases in pressure and temp

e.g. 3 km burial: increases P by 1000 atmospheres (bars)

28
Q

What causes changes in earth conditions?

A

Tectonic processes (burial and exhumation)
Magmatism
Weathering

29
Q

Why do basalt/gabbro rocks formed at MORs turn into eclogite in subduction zones?

A

Basalt/Gabbro -> Eclogite

transformation of minerals due to increased depth (subduction) [P, T increases]

30
Q

Mineral changes help drive …

A

subduction and move plates

31
Q

How are new elements introduced?

A

Weathering (e.g., oxidation)
Presence of aqueous fluids/gases

E.g., Hydrothermal Metamorphism mid-ocean ridges: interaction with H2O (added)

32
Q

What hydrous minerals does Pyroxene (no h2o) turn into?

A

chlorite
epidote
actinolite

33
Q

what are the processes for making a mineral?

A

Crystallisation from cooling molten rock -> minerals in igneous rocks
Increased pressure/temperature -> new minerals, in metamorphic rocks
Weathering -> new minerals formed by alteration of existing ones
Precipitation from aqueous fluids/gases
Growth of minerals in shells/teeth/bones

34
Q

what does it mean for a mineral to be metastable?

A

Many deep Earth minerals exist at surface out of their stability limit - thus they are metastable

35
Q

how are diamonds carried to the surface?

A

rapidly in host kimberlite magma

EOS 120 (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions