old stuff for geo final

when did the solar system form?

4.5 billion years ago

three aspects that define a mineral:

crystal structure

definitive chemistry

naturally occurring

which geologic era is defined as the Explosion of Complex Life?

Paleozoic

which principle of relative time has the greatest impact on society?

lateral continuity

what mineral group is most abundant in the crust?

silicates

what mineral is most useful in the study of paleomagnetism?

magnetite

what is paleomagnetism?

the study of the magnetism in rocks that was induced by the earth's magnetic field at the time of their formation

which of the following rock types is a higher potential risk for causing radon?

a. granite

b. limestone

c. slate

d. basalt

granite

what is the primary rock type found in the mantle?

peridotite

three processes that are main factors in how the solar system formed:

nuclear fusion

gravitational attraction

density differentiation

how did the moon form?

the impact of another protoplanet

what line of evidence tells us the core is made of iron and nickel?

meteorites

what geological form is where crust is being recycled?

trenches

what type of evidence is used to support the Big Band theory?

Doppler effect (red / blue shifting of the galaxies)

what physical property dictates which oceanic crust subducts in an island arc?

density

at an island arc, which type of crust subducts?

oceanic

what are lines of evidence Wegener used to support continental drift?

finding coal in modern day temperature climates

same fossils found across southern hemisphere continents

glacial striations

which of the following minerals is found in and vital to humans?

a. calcite

b. quartzite

c. apatite

d. fluorite

apatite

what is the only valid reason why continental drift was rejected by the time it was published in 1910s-20s?

unclear driving mechanism

him being German contributed, but certainly not valid

what is the most widely used absolute dating technique in geology?

zircon

which of the following is not a principle of relative time?

a. cross-dating

b. cross-cutting relationships

c. superposition

d. original horizontality

cross-dating

what is the primary use of olivine?

refractory materials (bricks, molds, etc.)

how did sonar end up playing a main role in developing plate tectonic theory?

mapped seafloor and found mid ocean ridges

which mineral is the most abundant in earth’s crust?

plagioclase feldspar

which of the following plate boundaries does not produce magmatism?

a. continental rift

b. mid-ocean ridge

c. continental collision

d. transform

transform

what is the product of the core’s dynamo?

earth’s magnetic field

what describes an erosional surface between horizontal sedimentary rocks and horizontal sedimentary rocks beneath?

disconformity

what is a disconformity?

erosional surface between horizontal sedimentary rocks and horizontal sedimentary rocks beneath

what information does paleomagnetism provide?

normal or reversed magnetic poles

latitude

longitude

what layer of the earth is entirely in the lithosphere?

crust

what type of unconformity is this?

angular unconformity

what is the one consistent thing produced by all radioactive decay processes?

heat

what plate boundary produces earthquakes that are largely irrelevant? why are they irrelevant?

mid ocean ridges

because they’re in the middle of the ocean, so they do not really affect life on land

which of the following is not one of the periods of the Paleozoic?

a. Permian

b. Paleocene

c. Cambrian

d. Devonian

Paleocene

when did dinosaurs go extinct?

65.5 million years ago

what silicate minerals are defined by connected silica tetrahedra forming consistent horizontal planes?

phyllosilicates

what behavior do p vs. s waves display?

s waves are transverse

p waves are compressional

where do p vs s waves travel?

p waves travel through all phases, s waves only solids

are p or s waves faster

p waves

density, thickness, and composition of continental crust

2.7-2.8 g/cm³

25-70 km thick

felsic composition

what rock type makes up the mare seas on the moon?

basalt

what radioactive decay system is responsible for producing radon?

²³⁸U -- ²⁰⁶Pb

what is a typical property of ionic bonds?

high solubility

what are used to define geologic periods of time?

unconformities and extinction events

what explains how our planet developed its internal structure?

density differentiation and gravitation

what mineral group is common but utterly useless other than being a minor gem type?

pyroxenes

what are the 9 abundant elements in the earth’s crust

Oxygen, Silicon, Aluminum, Iron, Calcium, Sodium, Magnesium, Potassium, and Titanium

what defines the edges of plate boundaries?

earthquake hypocenters

what is the term to describe fossils that were wide-spread but limited to specific time intervals?

index fossil

what property is most highly related to crystal structure?

cleavage / fracture

three important aspects of the tectonic Wilson cycle:

1. plate boundaries are largely responsible for most major natural disasters

2. changes distribution of species and greatly impacts the evolution of those organisms

   1. plate / continent distribution affects climate, weather, and greenhouse and icehouse conditions

what explains the rapid changes in density in the mantle?

changes in mineralogy

why does it matter that only 9 elements map up 98.9% of the crust?

it shows that most of the elements that we use / need are extremely rare

what principle of relative time is a result of gravity?

original horizontality

what physical properties of minerals relate to the strength of chemical bonds?

melting point

compressive strength

hardness

which of the following is not information that meteorites provide?

a. core is iron-nickel alloy

b. water on our planet is all extraterrestrial

c. stony chondrites are the same as crust / mantle

d. earth is similar to inner planets and asteroid belt

water on our planet is all extraterrestrial

what bonds are not very important for minerals?

Van der Waals bonds

what is the largest unit of geologic time?

eon

what is not a major factor in which why earth is habitable?

a. nitrogen levels

b. plate tectonics

c. earth’s mass

d. location to the sun

nitrogen levels

what are solid solution minerals?

minerals that can have a range of chemical compositions

what property is most highly affected by chemical impurities?

color

what is the primary problem with age dating techniques other than radiometric techniques?

they are only useful for very “recent” times

what explains the mechanism for how plate tectonics actually work?

whole mantle convection

layered mantle convection

plume driven convection

hybridized convection

three uses of clays and why is it used?

cement

toothpaste

ceramics

clays are useful in abrasives and thickening

three uses of micas and why is it used?

electronics

paint

cosmetics

micas have sheet-like, layered structure, chemical stability, and pigments that make them useful in these products

three uses of quartz and why is it used?

abrasive

cement

glass and lenses

abundant and durable, hard, stable, high melting point, has high optical clarity and transparency

feldspar uses and why?

aggregates (sand and gravel) that make up concrete, pavement, roads, etc.

fillers (paint, plastic, rubber)

tiles

highly abundant, hardness, fluxing ability

mid-ocean ridge:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

Mariana Trench

ocean-ocean

Pacific Plate subducted under Philippine Plate

continental rift:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

Rio Grande

South American and African plates

island arc:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

the Philippines

ocean-ocean

Philippine plate and Pacific plate

continental arc:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

Mt. St. Helen

oceanic-continental

Juan de Fuca Plate and North American Plate

continental collision:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

Himalayas

continental-continental

Indian and Eurasian plates

transform:

give geographical location and plates involved (ex. ocean-continental, Eurasian)

San Francisco Las-Angeles fault

oceanic-continental

Pacific Plate and North American Plate

explain what hotspots / plumes are, how they work, and give two geographical examples of them:

mantle hotspots / plumes are stationary movement of magma to the surface, forming landforms / islands. some examples include the Hawaiian islands, Yellowstone, Iceland, Canary Islands, and Galapagos

explain uniformitarianism and why it is important to understanding geology

attributed to James Hutton

concept that geologic processes that occurred in the past are the same that occur today

important to understanding geology because it helps relate events that occur today to the past

helped pioneer geologic time, especially relative time, including the principles that help to date rocks, events, etc.

what mechanism is affiliated with magma generation in mid-ocean ridges?

dropping pressure

what is information that Bowen’s Reaction Series provides?

silica content composition

mineral assemblages

temperature of formation

what is the dominant control on water solubility in magma?

pressure

what is the primary effect of physical weathering?

smaller grain size

what are mechanisms causing physical weathering?

dissolution

what is an example of a biological / organic sedimentary rock?

coal

what sedimentary feature is likely to be found in tidal flats?

mudcracks

colder and drier climates generally have:

mostly _________ weathering, with some other types

physical

characteristics of shield volcanoes:

large diameters (10-100s km)

mafic magma composition

shallow slopes

the longer sediment has been in transport, the more it is likely to be:

well-rounded and well-sorted

what type of magma is erupted at mid-ocean ridges?

mafic

what is leaching?

downward motion of ions through soil

what type of eruption is the most explosive?

Plinian

what is not one of the common types of sedimentary cements?

feldspars

why are feldspars not used in cements?

they are not ideal for strength and durability

which horizon is where accumulation takes place?

B-horizon

what is a good soil type of agriculture?

mollisol

ways volcanoes can change the weather / climate:

can produce SO₂ that produces acid rain that can produce lower-level clouds

can produce lots of CO₂ that causes a greenhouse effect

volcanic ash enters the stratosphere and increases albedo of planet decreasing sun radiation

characteristics of turbidities / turbidity currents:

display graded bedding Bouma sequences

can form from earthquakes, storms, and slope failure

dominated by clastic rocks

form on the continental slope onto the rise / plain

what type of sandstone is typical of tectonically active areas?

graywacke

what type of lava flow is formed first from the hottest lava?

Pahoehoe

the four processes involved in making sedimentary rock:

weathering

erosion / transport

deposition

lithification

magmas form along these types of plate boundary / earth feature:

divergent

continental collisions

subduction zones

hotspots (plumes)

what eruptive styles are produced from lava fountaining / spraying occasionally?

Strombolian

what type of volcanic eruption would you expect at a cinder cone?

strombolian