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Geology 120 > Test One > Flashcards

Test One Flashcards

1
Q

“Snows of kilmenjaro” by Hemingway

A

85% of our glaciers have melted and there hasn’t been such a high rate of melting since the 1900s but we have had droughts

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2
Q

Spheres of earth

A
  1. Geosphere-earths interior
  2. Pedosphere-soil
  3. Hydrosphere-water
  4. Biosphere-living things
  5. Atmosphere-air
  6. Cyrosphere-water in solid form
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3
Q

Chemical differentiation as earth cools

A
  1. Core:physical=solid iron
  2. Mantle:liquid
  3. Crust:earths surface
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4
Q

Stock v reservoir

A

Stock: your resource, what you’re taking
Reservoir:stock holder, what you’re saving

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5
Q

Types of systems (between stock and reservoir?)

A

Open: anything (matter and energy) in and out (ie ocean/lake rain goes in then water evaporates out)
Closed: things go in but can’t get back out (
Ike sun in a glass fishbowl)
Isolated: no change, not in or out
Dynamic: changes: more in or more out
Static: stays the same: some in some out

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6
Q

Steady state

A

When the stocks in a dynamic system remains balanced w time even though matter is being exchanged

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7
Q

Lithosphere

A

Crust broken into plates floating on upper mantle

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8
Q

Astherosphere

A

Upper mantle

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9
Q

Types of rocks

A
  1. Igneous
  2. Metamorphic
  3. Sedimentary
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10
Q

Two types of behaviors

A

Linear: even predictable
Exponential: spikes indefinitely like population

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11
Q

Reinforcing and balancing

A

Reinforcing: process may arise promoting further change in same direction; positive feedback
Ie) Ice, reflects sun so it’s colder so more ice forms
Balancing: change in one direction leads to events that reverse direction; negative feedback
Ie) clouds coverage

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12
Q

Pedosphere

A

Weather, erosion, decomposed rock.

Critical zone regulates natural things to provide life

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13
Q

Geosphere

A

Earths metallic interior and rocky outter shell

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14
Q

Hydrosphere

A

All water

  • most is salt water or freshwater that is locked up
  • hydrologic system (water cycle)
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15
Q

Atmosphere

A

Envelope of gases
21% oxygen
-everything else small amount
-co2 (and methane?) small naturally occurring but it’s increasing
We live in “troposphere” where oxygen is at its most comfortable level

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16
Q

Biosphere

A

Us :)
8.9 mil species
Lots depend on photosynthesis
60-90% of all cells is water: this is an example of the interaction between the biosphere and hydrosphere
-another example is the fact that carbon is the building blocks of cells

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17
Q

Cyrosphere

A

Ice
Frozen
Amount depends on the climate

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18
Q

States of energy

A

Gas, liquid, solid

-exchanges throughout the spheres

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19
Q

Types of energies (measured in calories?)

A

Kinetic-moving
Potential-held back energy like water at a dam
Thermal-heat energy

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20
Q

Energy starts by….

A

Coming from the sun
Insulation: how much sun/energy enters the earth
-some energy is trapped y clouds and greenhouse gasses

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21
Q

Energy budget

A

25% reflected by clouds
5%reflected by earths surface
25% absorbed by clouds
45% reaches us

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22
Q

Most energy we absorb

A 
Fossil fuels (81%)
Geothermal
Per country or per person (per capita)
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23
Q

Human population

A

Number one problem in environmental geology

Total Impact=individual impact x number of people

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24
Q

Hunters and gatherers

A

40k-9k bc

Less than a few mil people

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25
Q

Preindustrial period

A

9 bc

6 million people

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26
Q

Population growth

A

10% more people each year?.

10.1% growth of population per year?

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27
Q

Human population over time

A

100 years ago : 1-2 bil
40 years ago: 2.4 bil
30 years ago: 4-6 bil
2011(7 years ago): 7 bil

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28
Q

Limited resources

A

Renewable: we use but quickly replaced (sustainable)
Non renewable: finite/exhaustible
Inexhaustible: cant be depleted by human activity
-prolly soil but there was the dust bowl
-wind

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29
Q

Yeild

A

Most we can do without depleting a resource and giving it time to grow back

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30
Q

Sustainability

A 
To ensure resources are available for the future 
Why:
-socially just
-economy
-environment
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31
Q

Pollution

A

Contamination of a resource one with undesirable material

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32
Q

Waste

A

What’s left over after using a resource

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33
Q

Environmental impact

A

Population and per capita, amount environment segregation per resource

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34
Q

How do we know if pollution is causing degradation

A

If pollution per unit resource is high

  • over population
  • over consumption
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35
Q

Geological hazard v natural disaster

A

Geological hazard: Natural phenomenon/process, event with negative affects on human, environment, or property
Natural disaster: Sudden change results of ongoing process that affects humans, environment, or property

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36
Q

Risk

A

Magnitude of potential death, injury, or loss of property due to a particular hazard

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37
Q

Anthropocene

A

Time people have been here

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38
Q

Planetary boundaries

A

Operating in safe way for humanity

-absolute values uncertain

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39
Q

Energy

A

Ability to do work or a change brought about when force is applied
-kind of a system within itself like the sun

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40
Q

Processes

A

The manner in which change to a system occurs

  • erosion
  • subduction
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41
Q

Resource

A

Anything we get from our planet

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42
Q

Over consumption versus over population

A

Over consumption: one person using more than they need

Over population: too many people for the resources available (sometimes due to over consumption)

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43
Q

Parts of Scientific method

A
  1. Hypothesis- explanation of observations that’s based on physical principles
  2. Theory- hypothesis that’s survived repeated testing and accurately explain a wide variety of phenomenon
  3. Universal unifying theory- a theory that explains many types of phenomenons and has survived all challenges
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44
Q

Pseudoscience

A

False sciences, presented to be true but not

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45
Q

Difference between ocean crust and continental crust

A

Ocean crust: thin

Continental crust: thick

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46
Q

Isostacy

A

Mountains have deep roots so rise higher

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47
Q

Normal faults vs reverse faults

A

Normal: Where lithosphere (foot wall) rock slides downward relative to other rocks (hanging wall) along fractures
Reverse: hanging wall moves up relative to foot wall

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48
Q

Types of plate boundaries

A
  1. Divergent- two plates move away from each other. Constructive, builds land
  2. Convergent: where two plates collide. Two intersections can occur: A) continental-ocean or ocean results in subduction (one sliding under the other)
    B) continental continental results in mountain building by pushing against each other and raising
  3. Transform-two plates slide by each other
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49
Q

Cons of reverse fault

A
  • can produce earthquakes with megathrust
  • faulting is brittle deformation
  • inained Plane of failure separates rocks on either side of the fault
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50
Q

Thrust fault

A

Occurs when the plane of failure separating rocks on either side of the fault is less than 30 degrees from horizontal

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51
Q

Ductile deformation

A

Convergent boundaries are also locations of ductile deformation
-ingest temp and pressure cause rocks to behave like liquid and flow but remain in solid state
—results in formation of oil and natural gas

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52
Q

Transform boundary

A
  1. Strike-slip faulting- occurs when rocks slip horizontal along a vertical or near vertical plane
    -strike: orientation of the fault plane with respect to north
    -slip: the blocks of rock on each side is parallel to strike
    —mid ocean ridges opposite: right lateral v left lateral, appears opposite because ocean crust is moving away from ridge sediments
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53
Q

Who first noticed transform boundaries are opposite in mid ocean ridges?

A

J. Tuzo Wilson

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54
Q

History of plate tectonics

A
  1. Alfred wegener brought together most evidence, but not widely accepted
  2. Couldn’t explain mechanism causing continents to move, no one believed him till after he died
  3. Technology helped
  4. Sub “Meteor” found mount range under ocean
  5. Maurice Ewing in 1947 found lava flowing in middle
  6. Harry Hess said it’s “seafloor spreading” (lava under crust makes magnetic: leaves south enters north)
  7. Scientists started accepting hypothesis
  8. Discovered polar/magnetic switch (leave north enters south)
  9. Used seafloor maps and patterns of magnetism to prove seafloor spreading indefinitely
  10. Ages of fossils: closer to ridge younger farther away older
  11. Thickeners increases farther from ridge
  12. Track earthquakes and volcanoes and find all by ridges
  13. Plate tectonics driven by convection
  14. Magnum comes up in center of plate: hot spots
  15. Now we know why they move…. new thinking and new hypothesis
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55
Q

Evidence of plate tectonics from Alfred wegener

A
  1. Pieces of earth fit together
  2. Same fossils near where they would fit together
  3. Glaciers tore up the ground the same way
  4. Mountain belt extends where they would’ve been connected
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56
Q

What all did sonar help discover

A
  1. Continental shelves
  2. Continental slopes
  3. Abyssal plains
  4. Mid ocean ridges
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57
Q

How did harry Hess know the seafloor was spreading

A
  1. Ridges in all oceans
  2. Heat is greatest at center
  3. Ocean floor less than 2mil years old, land 4 bil +
  4. Plates destroyed when converge underneath
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58
Q

Why did the rocks move and Pangea split apart

A

Due to magnetic lava leaving south and entering north

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59
Q

How far can we detect eartherquakes

A

700 km (here to philly)

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60
Q

What does earthquakes happening on a plane support

A

The idea that a plate is sliding underneath another

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61
Q

Who are plate tectonics driven by convention

A
  1. Heat transferred so hot crust rises, cools, then sinks

2. Warm “astenosphere” comes up and spreads out…. where they hit each other the cooler denser one sinks

62
Q

Hawaiian islands related to magnum coming up at the center of plates (hot spots)

A
  • Hawaii was a long change on a hot spot and ask the old moved new formed
  • islands increase with age farther from the hotspot
  • hot spot moved south between 81-47 mya @ speed of 4 cm/year! Whole island chain moved
63
Q

Science is the best known evidence but….

A

It can change

64
Q

Movement of plate causes

A
  1. Forms mountain ranges
  2. Determines plant-animal species
  3. Determines geological hazards (earthquakes and valcanoes)
65
Q

Oceanic continental collision versus ocean ocean collision in converging plates

A
  1. Oceanic-continental collision: formation of ocean trenches along the boundary between the two plates; volcanic arcs can also be found parallel to the convergent boundaries due to melting of the oceanic plate
  2. Ocean-ocean collision: one oceanic plate is more dense forms volcanic island arcs
66
Q

Minerals

A

Composed on elements

67
Q

Minerals

A

Can’t be broken down further

  • naturally occurring
  • solid
  • inorganic
  • definite chemical composition
  • definite Chrystal composition (can be very large or very small)
68
Q

How are minerals identified by

A 
Luster: metallic or non
Hardness: scale “moes mineral hardness scale”
Cleavage: how it breaks
Taste
Smell
Magnetism
69
Q

Relationship between atoms, minerals, elements, and rocks

A
  1. Atoms
  2. Elements
  3. Minerals
  4. Rocks
70
Q

How definitive structure in a mineral relates to atom bonds

A

Definite structure of a mineral is based on atom bonds

71
Q

Groups of minerals

A
  1. Silicates: most common (silicons and o2) group of minerals within the earths crust! Quartz,muscovite,biotite,and fieldspars
  2. Carbonates: co3 main component limestone and so important to dissolution
  3. Sulfides (s): involved in the formation of sulfuric avid which gets in mining waters
72
Q

Rocks

A

Aggregation of minerals and of mineraloids

73
Q

What process produces different kinda of rocks

A

Igneous- volcanic eruptions
Sedimentary- weathering
Metamorphic- heat and pressure

74
Q

Magma versus lava

A

Magma: intrusive/plutonic, large crystals (cools slowly)
Lava: extrusive/volcanic, small crystals (cools fast)

75
Q

Pegmatitic

A

Large crystals

76
Q

Glassy vs vesicular

A

Glassy smooth

Vesicular kind of bubbles, Spongy

77
Q

Mafic vs felsic

A

Mafic: dark colored, iron magnesium
Felsic: light colored, silicone, petassium sodium, aluminum

Felsic—>intermediate—>mafic—>ultra mafic

78
Q

What determines rock type

A

Texture and composition

Ie garnet- intrusive (large crystals) felsic (light colored)

79
Q

Know figure 4-12 on PowerPoint 3

A

It’s a graph

80
Q

Texture

A

Based on How formed, environment, and composition

Ie igneous very strong because of interlocking christals (used for foundations) & good source of mineral resources

81
Q

Process of sedimentary rocks

A
  1. Compaction and cementation of sediments
  2. Precipitation forms solution***
  3. Sediments created through erosion and weathering
  4. Sediments building blocks of sedimentary rocks
82
Q

Erosion

A

Removal of sediments by wind, water, ice

  • transported the deposited somewhere else
  • cementation: glue back together
83
Q

Types of weathering

A

Mechanical: freeze and thaw cycle
Chemical: hydrolysis (chemical breakdown due to water) or dissolution (dissolved in water)

84
Q

Different compositions of sedimentary rocks

A

Clastic: Made from compaction and cementation of weathered rock fragments
Biochemical: made from compaction and cementation of something living
Chemical: made from precipitation which formed mineral Chrystal

85
Q

Texture of sedimentary rocks

A

Breccia- rivers/streams
Conglomerate- rivers/streams
Sandstone- beaches
Shale- deep sea/lagoons

86
Q

Small vs larger upsize and more vs less angular

A

Smaller sediment size and less angular=better sorting—>been in system long (older)
Larger sediment size and more angular=worst sorting—>younger/newer

87
Q

Sedimentary chararacterisits

A

Porosity-spaces betweeen grains; measured by percent of open space
Permeability- how well connected the pore spaces are

88
Q

Directions for checking porosity

A
  1. Pour water from your 100 ml cylinder into the 50 ml sample of rock/soil until the water is even with the top of the sample
  2. Look at cylinder, how much water left? Let’s say 83 ml
  3. So how many And ml poured?17
  4. What percent of 50 ml is that? 50/17=.35x100=35%
    4.
89
Q

Why are sedimentary rocks important

A

Contains things we want (shale contains oil natural gas, and ground water)

90
Q

Shale

A

Compaction shale-weakly cemented add water turns back to articles
Cementation shale-strongly cemented ya gotta last it (in general shale is relatively weak)

91
Q

Fossiliferous limestone

A

Dissolved through dissolution leaving caves behind, dimpled land, sink holes (Florida)

92
Q

Protolith

A

The parent rock, the original rock before metamorphoses

93
Q

Metamorphism….

A

Increases crystal size

94
Q

Foliated vs non foliated

A

Foliated: has layers?
No foliated: nolayers?

Foliation: weak points along those planes

95
Q

Index minerals

A

Help us determine what conditions metamorphic rocks formed under
Non-metamorphic—>low grade—>medium grade—>high grade

96
Q

What determines texture in metamorphic rocks

A

Aligning minerals, accomplished through

  • mechanically rotation grains
  • recrystaliaion and platey minerals into orientation perpendicular to stress
97
Q

Pros of non foliated in metamorphic

A

Slightly stronger

Grain size increases

98
Q

Importance of metamorphic rocks

A

Marble (homes statues)

Schist weathered to turn into NC state soil

99
Q

Rock strength in metamorphic rocks

A

Related to composition

100
Q

Stress

A

Force per unit area measured in Newtons (N)

-measured in pascals (n/m^2 when m^2=area)

101
Q

Strain

A

How the material responds
Can occur in two ways:
1 temp strain: called elastic deformation (think of bending a stick or stretching a rubber band NOT until it breaks) remove stress nd goes back to normal
2 perm strain: called plastic deformation and behaves in 2 ways we spoke about within the earth, brittle and ductile

102
Q

How are rock structures formed

A

From strain due to stress faults, folds, unconfirmity

103
Q

Hydrologic cycle

A
  1. Evap
  2. Recip
  3. Infiltration/run off
  4. Transportation
  5. Evapotranspiration (through vegetation)

Movement through cycle: surficial process
-responsible for erosion, transport, and deposition of earths materials
—-water,wind,ice

104
Q

Glaciers today vs Pleistocene glaciers

A

Today: 10 % of earth
Pleistocene: 30% of earth

105
Q

Basal sliding

A

Over water saturated ice and rock

106
Q

Internal flow

A

Icessreams

107
Q

Glaciersize

A

Can be several km thick:
Below: 60m deform “plastically”
Above is the”brittle zone”-where crevassesform

108
Q

Loess

A

Wind blown silt, leaves cross beds

109
Q

Mineral resources

A

Exceptionally important globally and regionally

110
Q

Critical minerals and ores

A

-important in producing products and who’s restrictions have global economic consequences
Ores: industrially important metals minerals, mined fro ore deposits
Tailings: leftover minerals associated with the deposit and not needed
Economic concentration factor-in order for a deposit to be economically viable it must be abundant in the deposit; this is many times past its crustal abundance

111
Q

Types of ore deposits

A
  1. Hydrothermal ore deposites
  2. Igneous ore deposits
  3. Sedimentary ore deposits
112
Q

Mining and environment

A
  • allows elements o be mobilie andmoved around the sphere
  • Ores mined crushed and or smelted with other materials to produce molten substances where the element in Question can be separated
  • release of lead (pb),chromium(cr), and mercury (Hg) can have dangerous effects
  • once mined cant go back —-> affects water and produces sulfur dioxide gas and cant fix land
113
Q

Heap leaching

A

New mining technique used to extract metals from oxide and low grade sulfur ores- they are crushed and spread with cyanide to release gold, or sulfuric acid to release copper

114
Q

Biogeochemical cycles

A

-metal cycling through earths systems

115
Q

Miningregulation

A

-General mining act 1872:establishes exploring for and mining resources on public land and acquiring regulation for the protection of mining claims
-Federal land policy management act 1976:updated the regulation of surfaceland to 1. Require permits and 2. Have an environmental assessment and 3. Reclamation of land once mining done
(however something new reared its ugly head…. an environmental conscious!)

116
Q

The department of interior manages

A
  • bureau of land management
  • national park services
  • fish and wildlife

—forest services is under the dept of agriculture

117
Q

Mechanical weathering

A

Breaking down of rocks into smaller pieces
Types:
1. frost wedging- alternate freezing and thawing of water
2. unloading- exfoliation due to reduction in confining pressure
3. thermal expansion- alternate expansion and contraction due to heating and cooling
4. biological activity- plants and animals interactions

118
Q

Chemical weathering

A

breaks down rocks through chemical reactions

  • most important agent in chemical reactions is water (reasoonsible for transport of ions and molecules involved in chemical process)
    1. dissolution- aided by small amounts of acid in water, soluble ions are retained in the underground water supply
    2. oxidation- any chemical reaction in which a compound or radical loses electrons, important in decomposing ferromagesian minerals
    3. hydrolysis- the reaction of any substance w water, hydrogen ions attacks and replace other positive ions
119
Q

Soil definitions

A
  1. Strictly geological science points of view (compositional)
    - ie 25% air 45% mineral mater 25% water 5% organic mater
  2. Applied science (engineering) point of view
    - can be removed without blasting
120
Q

Soil formation

A

Soils are derived from the weathering of rock and the introduction of organic and inorganic materials

121
Q

Soil formation is further altered/modified by soil organisms, what are the two types?

A

depending on proton of the bedrock

  1. Residual soil-parent material is the underlying bedrock
  2. Transported soil-ford in places on parent material that has been carried elsewhere and deposited OR the soil was modified elsewhere then transplanted
122
Q

Soil fraction factors

A
  1. Climate- most influential control of soil formation, key factors are temp and precipitation
  2. Topography- steep slopes often have poorly resolved soils, optimum terrain is a flat to undulating upland surface
  3. Parental material time- amount of time for soil formation varies for different soils for
  4. Ending on geological and climatic conditions
  5. Organic process- organisms influence the soils physical and chemical properties as well as furnish organic matter to the soil
123
Q

In what direction does soil forming operate

A

from the surface downward

124
Q

Zones/soil horizons

A

Vertical layers of soil
1. O horizon- concentrated organic matter, twigs, leaves-dark brown/Black
2. A horizon- organic matter plus mineral debris
3. E horizon- zone of leaching or .eluviation”, light in color, fe oxides removed
4. B horizon- zone of accumulation, materials brought down from above
A. Bt: Argillic b clay enriched
B. Bk: Rich in calcium carbonate (CaCO3)
C. K: Mostly CaCO3, caliche
5. c horizon- altered “Parent material”
6. R horizon- bedrock
7. Hardpan- compacted layers: impermeable

125
Q

Soil texture

A

Result of mix of
Clay (< .004 mm)
Silt (.004-.074 mm)
Sand (.074 to 2.0 mm)

126
Q

Water content

A

Within the soil, pore spaces are filled w air or water
Saturated- completely filled pore space.
Unsaturated- partially filled pore spaces. Flow is fastest in middle as film thickens around particles

127
Q

Soil taxonomy

A

classifies soils based on number of horizons, nutrient status, organic content, color, Nd climatic association

  1. Entisols: no horizon, development-young soils
  2. Aridisols: desert soils, los organics (gypsum, caliche, salt)
  3. Andisols: volcanic
  4. Oxisols: oxidized, tropical
128
Q

Engineering properties of soil

A

Soil is composed of 3 states [solid (minerals/organisms) gas (air) liquid (water)

129
Q

Plasticity

A

Water content
refers to the behavior of fine grained soils and the soils “plasticity index” dependent upon water content
liquid limit- above this amount of water soil behaves like liquid
plastic limit- above this amount of water soil behaves like a solid
between these two amounts defines the plasticity index,! Too small an amount and the soil can turn into liquid, (liquefaction) and if the index is large (>35%) it means the soil can expand and contract

130
Q

Shrink

A 
swell potential (gaining and losing water)
	refers to potential of soils to gain or lose water as a consequence of how much clay 
		expansive soils clays such as montmorillonite, could expand up to 15% but even 3% hazardous
131
Q

Soil strength

A

ability to resist deformation
Cohesion- ability of grains to stick together (water)
Friction- between grains and from density and weight of material above

132
Q

Sensitivity

A

refers to how easily a soil loses strength due to disturbance (manmade or natural)
during Earthquake the tremors may shake water saturated soils and turn them to liquid,liquefaction

133
Q

What two things do rate of erosion depend on

A
  1. Raindrop impacts
  2. Sheet flow (run-off)
    A. Rills
    B. Gullies
134
Q

What is one of the most common pollutants?

A

Sediments
natural: dust bowl
Man made: pollution of soils
• organic chemicals (hydrocarbons, pesticides)
• Heavy metals (cadmium, nickel, selenium, lead)
◦ Smelting of copper, preparation of nuclear fuels
• Solvents

135
Q

Bioremediation and soils as filters

A

Bioremediation allows for microorganisms to be introduced which use the pollution as food
Soils-sand and gravel can also filter out pollutants as they move through groundwater

136
Q

How much of farmable land has been lost and in what time frame

A

1/3, most in last 40 years

137
Q

Better farming processes

A
  1. No till agriculture
  2. Contour plowing
  3. Terracing slopes
138
Q

Mass wasting

A

Down-slope movement of earth materials

139
Q

Landslide statistics

A

25-50 deaths in the U.S. annually
Annual cost $3.5 billion
Natural and manmade

140
Q

Slope form

A
  1. Cliffs (hard infuriated rock like granite)

2. Hills and valleys formed in weaker rocks and soils

141
Q

Parts of a cliff

A

Free face-face of cliff

Talus slop-rock fall deposits at bottom or along edge of cliff

142
Q

Three parts of hills/valleys

A
  1. Convex slope-where it starts
  2. Straight slope-middle where around 90 degrees
  3. Concave slope-at bottom where curves back horizontal
143
Q

How is slope stability determined

A

By the ratio (safety factor) of

  • resisting forces to
  • driving forces
144
Q

Safety factor scale

A

More than one: resisting forces are larger (may be stable)

Less than one, driving forces larger (unstable)

145
Q

Examples of resisting and driving factors

A

Resisting:

  • material shear strength
  • Length of slip plane
  • Thickness of overburden
Driving:
-weight
0area of overburden
-thickness of overburden
-slope (angle)

Multiple all these numbers together then do decision

146
Q

Mass waiting classification

A

Rotational (slow to fast) movement & rock and soil materials=slumps
Translational (slow to fast) movement & rock and soil materials=slides
Falls (fast) movement & rock and soil material=Falls (topples)
Falls (slow) movement & rock and soil materials=Creep
Flows (rapid) movement & rock and soil materials=debris flow
Flows (very rapid) movement & rock and soil materials=debris avalanche

147
Q

Landslide causes:

A

Too much water
-reduces cohesion (remember liquid limit)
-mostly a natural process (precipitation); although increased urbanization leads to more pavement-hence-runoff!
Too much load (overburden)
-natural(from weathering/depositional process)
-manmade (from construction/road creation
Steeping the slope
-construction which removes material at the base of the slope

148
Q

Minimizing/reverting landslide hazards

A

Identify potential hazard areas!

  • land slide inventory
  • land use considerations
    2. Remove the water (drainage control)
  • surface drains
  • drainage pipes at slope base
    3. Grading (if done right)
  • reduces slope steepness
    4. Electronic monitoring
  • using satellites and computers
149
Q

Why do tungsten diamonds break?

A

-Tungsten carbide wedding rings, may have diamonds in them but the band is tungsten. The tungsten ring can be brittle because of the hardening process

150
Q

Manmade diamonds often are created using combinations of nickel, cobalt and iron, and what soft mineral with carbon?

A

Cubic zirconia diamonds are made from zirconium dioxide-8.85 on mohs scale

151
Q

How do coquina the rock and coquina the shell relate

A
  • coquina is a rock composed of broken bits and pieces of shells
  • coquina shell, is the most common name for the bivalve species Donax variability
  • coquina comes from he Spanish word for “cockle” or “shellfish”

Geology 120 (4 decks)

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