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Applied Science 151-Geology
Queens Engineering Undergraduate Midterm Review: Prof. Heynes
115
Geology
Undergraduate 1
10/22/2013

Additional Geology Flashcards

 


 

Cards

Term
In trying to reach a design solution, what don't you have?
Definition
Unlimited time, knowledge, and resources.
Term
What is the process of optimization? (Hint think of Modelling).
Definition
Problem -> Model the Present System -> Model the Design Solution -> Implement the Design Solution
Term
Which moves more resources annually, human consumption or total mass of sediment transported into the sea each year?
Definition
Humans: 60 x 10^9 tonnes per year
Sediment: 16 x 10^4 tonnes per year
Term
Define Sustainable Development:
Definition
development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
Term
A is proportional to M*E*S*I / P
What do these variables stand for?
Definition
A=Level of affluence/Standard of Living
M=Materials
E=Energy
S=Sinks
P=Space/Population
I=Ingenuity
Term
What is the formula for the time until population doubles, for a growth rate x?
Definition
70/x
Term
What is the exponential growth formula used to determine future populations?
Definition
Population=(Present Population)(e^(growth rate)(time))
Term
What must the long term growth rate of the human population be for a sustainable future?
Definition
0%
Term
What is the Coasting effect in terms of populations and growth?
Definition
If we reach 0% population growth, it will still take many years for the population to level off or decrease
Term
What is the definition of abundant and scarce metals?
Definition
Abundant: more than 0.1% of the earths crust
Scarce: less than 0.1% of the earths crust
Term
Define a Mineral Deposit:
Definition
A local accumulation of a specific "mineral"
(A mineral can be anything)
Term
Define Ore Deposit:
Definition
A deposit of minerals that can be 'mined' profitably.
Term
Define Reserve, in terms of resources:
Definition
economic amount discovered but not yet extracted
or
sum of all known ore deposits
Term
Define Resource:
Definition
estimated total economic amount available
or
estimated sum of all possible 'ore' deposits
Term
What are 3 things that can be done to manage resource crisis?
Definition
1. Conservation
2. Switch to a renewable resource
3. Better recycling
4. Reduce population or need
5. Ingenuity
Term
What are the 'Five Reservoirs?' (In terms of earth systems engineering).
Definition
1. Atmosphere
2. Hydrosphere
3. Solid Earth
4. Life
5. Stars and Planets
Term
What is the cause of the 'sawtooth pattern' of the CO_2 levels in the atmosphere?
Definition
Winter, trees dormant and not extracting CO_2
Summer, trees active
This effect is dominated by the northern hemisphere
Term
How do we measure the CO_2 levels from thousands/millions of years ago?
Definition
Analyze air bubbles trapped in ice.
Term
What natural earth cycle has historically had the most dramatic effect on CO_2 levels in the atmosphere?
Definition
The cycle of glacial and interglacial periods.
Term
What three things cause the glacial periods?
Definition
Eccentricity: Variations in the earth's orbit (100,000 year cycle)
Obliquity: Earth's til varies (41,000 year cycle)
Precession: Earths 'wobble' (20,000 year cycle)
Term
What were the times of peak coal formation?
Definition
300 million years ago, (first major land plants)
80 million years ago, (first flowering plants)
Term
What is the average density of the earth?
Definition
5.5grams/cm^3
Term
What is the importance of Earth's magnetic field?
Definition
Blocks harmful radiation from reaching most places on earth
Term
What is synergy, in terms of hazards?
Definition
One or more hazards combined can be come many times more deadly.
Term
What three things determine the intensity of a hazard?
Definition
Absolute amount: how far outside the damage threshold it is
Duration: How long outside damage threshold
Rate of Change: How quickly the intensity rises.
Term
Risk is proportional to:
Definition
The probability of the Hazard occurring, multiplied by the severity of the consequences of the hazard.
Term
What are the 5 steps of Risk analysis?
Definition
Understanding the Hazard
Determining the risk from the hazard to regions of interest
Determine ways to reduce severity or probability
Do a cost/benefit analysis
Implement mitigation techniques
Term
What is the Elastic rebound theory in terms of earthquakes?
Definition
The rigid portion of the earth can store elastic potential energy
Term
Fault:
Definition
a break or crack in the rock where there has been appropriate displacement.
Term
Earthquakes happen when either:
Definition
a fault forms
or there is movement on a pre-existing fault
Term
Strike Slip Fault
Definition
Horizontal Motion
Term
Dipslip Fault:
Definition
Vertical motion
Term
Focus:
Definition
the point source of energy release from a fault
Term
Epicentre:
Definition
the point on the earths surface that is closest to the focus
Term
Define Surface waves, and the two types of surface wave.
Definition
Formed when seismic body waves reach the earths surface
Rayleigh: Circular wave motion
Love: horizontal/side-to-side motion
Term
Body Waves:
Definition
Energy that radiates from an earthquakes focus
Term
Velocity of P and S waves is proportional to:
Definition
Elasticity/Density
Term
What is the compressibility modulus?
Definition
stress needed to compress a material
Term
What is the shear modulus?
Definition
stress needed to change the shape of a material
Term
S-waves cannot pass through:
Definition
Liquids
Term
At what depths do earthquakes occur?
Definition
all occur at less than 700km in depth
Term
Material Amplification Effect:
Definition
Soft Soils shake more than Stiff Soils shake more than Rock
Low Velocity Medium High Velocity
Large amplitude Medium Low amplitude
Term
What are the 5 causes of Tsunamis:
Definition
Seafloor Earthquakes
'underwater' landslides
Collapse of the flank of a volcano into the sea
Submarine volcanic explosion
Meteorite impact
Term
How does dam construction contribute to seismic risk?
Definition
Loading of the earth with excess water changes the 'stress regime' causing quakes
Term
Which travels faster, P-waves or S-waves?
Definition

P waves

P=Primary

S=Secondary

Term

How do we assess the seismic risk in an area?

 

Definition

Locate and determine the nature of the faults in the area

Decide if they are Inactive, Active or Potentially Active

Study history of earthquakes in the area

Determine Recurrance Interval

Set up Seismometers

 

Term
How do we manage the risk of Earthquakes? (4 things)
Definition

Land use planning and zoning

Building Codes

Resistant Building Designs

Set up warning systems and emergency response plans

 

Term

How do we manage the risk of Tsunamis?

 

Definition

Early warning systems

Natural shorelines, (vegetation takes most of force)

Limit popolations along shorelines

Provide Tsunami Education

Term
Seismic Gaps
Definition
Place in seismic record where earthquakes have not occured for  a period of time greater than the recurrance interval
Term
Define Dilitancy
Definition
Formation of microcracks in rocks preceding an earthquake
Term

Dilitancy can lead to: (4 things)

 

Definition

Ground Bulges

Foreshocks

Increase in Radon Levels in Wells

Drop in water levels in wells

Term
Define Occam's Razor:
Definition
Choose the simplest solution that fits the data
Term
How do waves behave when refracting between different mediums?
Definition

Dense -> Light: Away from normal

Light -> Dense: Towards normal

Term
Why do some seismic waves arrive sooner than expected?
Definition
They spend more time at depth at a higher speed.
Term
What does the S-wave shadow zone indicate?
Definition
The centre of the earth is liquid.
Term
What is the Mohorivic Discontinuity?
Definition
The MOHO layer, the boudary between the crust and the mantle.
Term
Define the Lithosphere:
Definition
The outer rigid part of the earth, 100km thick including the crust and the upper part of the mantle
Term
Define the Asthenosphere:
Definition
From the lithosphere down to approximately 500 feet, plastic material
Term
What does the prescence of Earths magenetic field tell us about the nature of Earths core?
Definition
Must be made of liquid iron, as it acts as a self esciting dynamo.
Term

What are the two types of meteorites?

 

Definition

Chondrites (Iron meteorites): Mainly elemental Iron

Achondrites (Stony meteorites): less iron

 

Term
What are the two defining characteristics of chondrite meteorites?
Definition

Spherical Chondrules, (Olivine and Proxene)

Bits of elemental iron

Term
What do chondritic meteorites tell us about the history of the earth?
Definition
Originally the earth was chondritic, but over time it experiences differentiation.
Term

What are the top three elements in the earth by weight?

 

Definition

Fe: 33%

O: 31%

Si: 16%

Term
What are earths current sources of heat energy?
Definition

Heat left over from the beginning of earths formation

Continual gravitational sinking of iron

Decay of radioactive elements

Term

How does earth get rid of its heat?

 

Definition
A combination of conduction and Convection
Term
In plate techtonics, the ______ (rigid) slides around on the _________ (plastic).
Definition

Lithosphere

Asthenosphere

Term
What are the characteristics of a contructive plate margin?
Definition

Upwelling part of the convection cycle

new lithospheric plates are produced and move apart

new ocean crust produced.

Term
What are the characteristics of destructive plate margins?
Definition

Sinking in the convection cycle

Lithospheric plates are destroyed

Ocean lithospheric plates subduct

 

Term
Define Mass wasting:
Definition
The downslope movement of solid Earth materials under the influence of gravity
Term

What determines whether landlides occur:

 

Definition

Slope Steepness

Nature of the Material

Triggering Effects

Term
Define Permafrost:
Definition
permanently frozen ground
Term
Define Solifluction:
Definition
Melting of the permafrost in the active soil layer causes landlsides
Term
Define Safety Factor and its basic formula in terms of lanslides:
Definition

A measure of the stability of a slope

(Resisting Force)/(Driving Force)

Term
Define Porosity:
Definition
The amount of empty space between soil particles
Term
Define Permeability:
Definition
The ability of water to penetrate a soil
Term
What factors affect slope stability in rock? (4 things)
Definition

Sedimentary bedding planes

Metamorphic bedding planes

Faults

Joints

Term
How do joints form in rocks?
Definition

Release of pressure when buried rocks are brought to earths surface

Squeezing of rocks

Shrinking of igneous rocks as the cool at earths surface

Term
How do we mitigate the effects of mass wasting?
Definition

Land Use planning

Stabalize the Slope

Slope Monitoring

Term
How can we stabalize slopes with risks of landslides?
Definition

Drainage

Rock Bolts

Mesh Screens

Retainign Walls

Cut Benches

Vegetation

Term
How can we monitor slopes with risk of landslides?
Definition

Tiltmeter

GPS

Geophones

Study Water Content

Term
What two things determine the behaviour of rocks and aggregates?
Definition

The properties of the minerals that they consist of

The bulk propertis of the rock

Term
A mineral is defined by two things:
Definition

Structure

Composition

Term
What are the four bond types?
Definition

Ionic

Covalent

Metallic

Intermolecular

Term

Define Polymorphs:

 

Definition
minerals with the same chemical composition but different structure
Term
What are the five silicate structures?
Definition

Single (Isolated) Tetrahedral

Single Chain

Double Chain

Sheet Structure

Framework

Term

What are the characteristics of Sand Soil?

 

Definition

mostly Quartz

strong framework structure

spherical particles provide good drainage

Term
What are the characteristics of Clay soil
Definition

mostly clay

tiny particles with surface charges packed tightly together

weak sheet structure

poor drainage

shrink and swell

Term
Where are abundant metals found?
Definition

Essential components of silicate and non-silicate minerals

 

Term
Where are scarce minerals found?
Definition
mainly atomic substitutes in silicate minerals
Term
What three things control grain size in igneous rocks?
Definition

Rate of cooling of magma

Viscosity of Magma

Percentage of Volatiles

Term
What affects the melting temperature of a mineral?
Definition
Pressure
Nature of neighbouring minerals
Term
When partial melting occurs, the rock that is released from the original rock is more ______ than the other components.
Definition
Felsic
Term
What are the layers, from top to bottom, of an igneous intrusion?
Definition
Felsic
Intermediate
Mafic
Ultramafic
Term
What are the two methods of Magmatic Differentiation?
Definition
Squeezing out the liquid, leaving the solids behind
Hardened crystals sink to the bottom
Term
Where do deposits of chromite occur?
Definition
In ultramafic rock
Term
Where do deposits of copper occur?
Definition
In granite porphyry intrusions
Term
What are the relative viscosities of felsic and mafic magma?
Definition
Mafic -> Low viscosity, low water content
Felsic -> Hight viscosity, high water content
Term
What is the two forms magma can reach the surface as?
Definition
Lava, or pyroclastic material
Term
What are the two ways magma can reach the surface of the earth?
Definition
Fractures (Fissures)
Volcanic Cones
Term
What are the dangers of fissure eruptions?
Definition
Release of CO_2 and SO_2 gas
If extremely large can cause mass extinctions
Term
What are the three types of Volcanic Cones?
Definition
Cinder Cone
Strato Volcano
Shield Volcano
Term
What is the most dangerous type of volcano? Why is it so dangerous?
Definition
Stratovolcanoes. This is because the material it releases is felsic or intermediate and has a high water content. This water expands and explodes out the top of the volcano.
Term
What are the dangers of Air-fall ash, and Ash clouds?
Definition
can cause major economic damage and bury cities
can block suns rays and lower global temperatures
Term
What are the dangers of ash-flow?
Definition
Nuee Ardente: Eruption pillar collapses and travels down the side of the mountain
Pyroclastic surge: travel more than 300km/h for up to 10km
Term
What is a lahar?
Definition
Ash on flanks of volcanoes mix with melted snow and create a mudflow
Term
What are the methods of mechanical weathering?
Definition
Joint formation
Frost Wedging
Biological Activity
Abrasion
Term
What are the methods of chemical weathering?
Definition
Action of Water (Hydrolysis)
Water can also be acidified
Term
What is useful about laterite soil, and where does it form?
Definition
Main source of bauxite (aluminum) and iron oxides
Forms in humid tropical climate
Term
What are the two types of sedimentary rocks?
Definition
Clastic: particles
Chemical: Ions in solution
Term
What does particle size in sedimentary rocks tell us about the environment of deposition?
Definition
Large size, high energy.
Small size, low energy.
Term
What does the degree of sorting in sedimentary rocks tell us about the environment of deposition?
Definition
Well sorted, long period of deposition
Poorly sorted, short period of deposition
Term
What were the two main types of sedimentary rocks discussed?
Definition
Limestone: Deposits of shell fragments
Chert: shells of microfossils
Term
What are some Evaporites?
Definition
Gypsum
Potash
Rock Salt
Term
Where is banded iron formation most commonly found?
Definition
alternating with layers of chert
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