Geology Final Exam Review- Building Planet Earth

Front 1

how old is the Universe?

Back 1

~15 BYA

Front 2

how do we know the age of the Universe?

Back 2

evidence the universe is expanding-- "red shift" is an increase in wavelengths of lightwaves travelling thru space

Front 3

how old is Earth?

Back 3

~4.6 BYA

Front 4

how do we know the age of Earth?

Back 4

radiometric dating-- measuring amts of parent and daughter isotopesin rock to find age in conjunction w/ their constant rates of decay

Front 5

what is the basic structure of Earth?

Back 5

inner/outer core, mantle. crust

Front 6

why is this the basic structure of Earth?

Back 6

impacts of giant bodies (mars) and decay of rad isotopes causes heat during Es accretion-- produces molten E, dense materials to center, less dense to surface

Front 7

how does Earths structure influence its history?

Back 7

less dense silicates floated to surface to produce magma ocean-- cooled to form feldspar rich coast-- precursor to todays oceanic crust

Front 8

What is the geological tome scale?

Back 8

organizes history of E into eons, eras, periods, and epochs. precambrian is rock w/o discernible fossils, cambrian is when fossils appear, fossils are boundary.

Front 9

time zones: largest to smallest

Back 9

eon, era, period, epoch.

Front 10

what are the eras in the phanerozoic?

Back 10

paleozoic- old life
mesozoic- middle life- dinos
cenozoic- modern life- mammals

Front 11

dates of archean eon?

Back 11

4.6-2.5 BYA

Front 12

dates of proterozoic eon?

Back 12

2.5 BYA-545 MYA

Front 13

dates of phanerozoic?

Back 13

545 MYA- current

Front 14

what events separate the eons?

Back 14

archean- life, rocks in Cratons, E gets structure

Front 15

what was early Earth like?

Back 15

*asteroids coalesced to form
*E emitted and retained gas to make own atmosphere
*volcanoes emitted: water vaopr (#1), hydrogen, HCl, carbon mono, carbon dio, N, methane, ammonia
*can't handle life- less oxygen
*oceans form from water vapor
*salts from rocks-> river-> oceans
*many meteorite impacts
*double the heat produced, lithosphere in small plates

Front 16

When did life begin?

Back 16

~4.2 BYA

Front 17

how do we know when life began?

Back 17

before 4.2 bya asteroid impacts produced to much heat for life to emerge

Front 18

how does proterozoic geology differ from archean geology?

Back 18

large cratons emerge late in archean-- deep water deposition and greenstone belts
large cratons persist thru proterozoic- extensive record of deposition in shallow seas; more unmetamorphosed sed rocks than archean available for study

Front 19

what evidence is their for planetary snowball events?

Back 19

ice cover ends land weathering
mo more CO2 drawdown
oceans become anoxic
volcanoes continue to release CO2 and levels rise
CO2 leads to Greenhouse Spring- 50C
explains post high weathering and tropical conditions

Front 20

what evidence is their against snowball evens?

Back 20

how did life survive?
couldve not totally frozen- keeps life
proposed duration isnt long enough

Front 21

what is ediacarian fauna

Back 21

the beginnings of modern life when animals burst onto scene at end of proterozoic

Front 22

why is edicarian fauna important?

Back 22

precursors to modern animals

Front 23

why is ediacaran fauna different?

Back 23

unskeletonized, no opening for mouth or anus, absorbed nutrients, preserved in mudstones

Front 24

how did life change in the ediacaran and cambrian?

Back 24

life emerges in proterozoic/ediacaran-- explodes in cambrian

Front 25

how does cambrian fauna differ from ediacaran?

Back 25

skeletonization, teeth, trilobites

Front 26

origin
extinction
diversity

Back 26

new species
last memeber of species dies out
# species present, #originations/extinctions

Front 27

mass extinction

Back 27

large % of species dies, global catastrophe-- loss of diversty, many taxa lost at once

Front 28

Ordivician radiation

Back 28

diversification in Ordovician
New marine species and genera originate at some of the highest rates known
Just as importantly, they don’t go extinct as quickly as Cambrian taxa

Front 29

Cambrian fauna

Back 29

trilobites, inarticulate brachiopods, weird stuff Mostly extinct (except the brachs)

Front 30

paleozoic fauna

Back 30

Articulate brachiopods (calcite, not apatite)
Bryozoans (new! Most complex colonial animals alive)Crinoids and other stalked echinoderms
Rugose and tabulate corals (extinct relatives of modern)
Some mollusks (nautiloids, primitive snails and clams)
Early fish and conodonts

Front 31

mesozoic modern fauna

Back 31

Much more active organisms (clams, snails, bony fish)
Paleozoic survivors often continue, but rare

Front 32

how was silurian diff from ordovician

Back 32

ordovician glaciation over-- warmer climates, rediversified seas for modern life

Front 33

how did plants colonize land in devonian

Back 33

vascular plants develop new tissue-- wood-- plants can stand on own, forests

Front 34

how did plants change the world in devonian

Back 34

plants cause nutrient crisis and global cooling-- leads to one of biggest mass extinctions in pahnerozoic (late devonian)

Front 35

what happened to marine faunas during devonian?

Back 35

fish radiate extensively before mass extinction kills of 57% of marine genera

Front 36

how did late devonian extinction differ from end of ordocivian extnction

Back 36

devonian caused by plants, ordovician extinction caused by glaciers and lowered sea level, cooling

Front 37

how did coal start to form in carboniferous
how did climate change

Back 37

cooling continues, seas recover, plants continue to dominate
first appearance of coal as massive coal swamps develop
brings down CO2
lack of greenhouse effect
more cooling

Front 38

carboniferous: how did vertebrates colonize land? what enabled them to leave water?

Back 38

insects most successful; first to use wings
amphibians colonize as herbivores/carnis etc; develop biting jaws

Front 39

how did plate movements affect global environments in carboniferous and permian

Back 39

carbo- gondwanaland heads north to collide w/ laurussia--results in alleghenian orogeny and development of pangea
perm- pangea heds north
allghenian continue--
extremely dry conditions, spread of desert belts
gondwanan glaciers shrink--warming--rising sea levels

Front 40

how did enviros change from permian to triassic?

Back 40

from greatest mass extintion of phanero in permian to triassic recovery and new diversification- raised sea levels, climate still warm and dry, another mass extinction at end of triassic

Front 41

stresses triassic survivors had to endure

Back 41

rising seas, hot and dry conditions, mass ex at end

Front 42

how did ecosystems get reorganized in mesozoic

Back 42

extinction in triassic, rediversification, dinos dominate

Front 43

what adaptations allowed reptiles to dominate

Back 43

upright stance, active, fast growing, social

Front 44

how did pterosaurs adapt to take flight

Back 44

developed long wings and hollow bones

Front 45

how did the end-triassic extinction provide dinos with their big break

Back 45

most terrestrial vertebrates killed off

Front 46

what was a dino? what do we know about their lifestyle?

Back 46

social animals, death assemblage, guard eggs, moved quickly, lots of activity, competition

Front 47

who are the dinos closest living relatives

Back 47

reptiles

Front 48

what allowed plants to really diversify in the cretaceous

Back 48

ascendency of flowering plants, angiosperms

Front 49

evidenc of asteroid impact at end of cretaceous

Back 49

wiping out of most genera, nuclear winter, global warming

Front 50

10 km rock drops in mexico equivalent to

Back 50

100 million megatons of TNT damage

Front 51

who survives cretaceous asteroid

Back 51

marine taxa that eats organic matter bc of large populations
small land animals
freshwater ecosystems (ex frogs)
omnivores

Front 52

what is a mammal

Back 52

enodthermic vertebrates characterized by body hair, legs positioned fully under body, sweat glands, some for milk

Front 53

how did mammals adapt to life w/o dinos
cenozoic

Back 53

grow larger to dominate

Front 54

how did birds compete
how did they avoid competition in cenozoic

Back 54

daytime v nighttime feeding with bats to avoid competition

Front 55

how did sea life change in cenozoic

Back 55

corals dominant again
calcerous plankton come back
vertebrates return to seas (ex whales)

Front 56

evolutionary advances of plants in cenozoic

Back 56

grass-- growth from bottom makes grazing ok

Front 57

how does grass affect ecosystem/ grazers

Back 57

rodents, snakes eat grasses

grazers must develop continuously growing teeth; grass silica wears down

Front 58

major plate tectonics in cenozoic

Back 58

continents continue to break up
collisions betw continents
CO2 drawdown from collisions-- massive glaciers

Front 59

how did plate movement and climate affect distribution of species
cenozoic

Back 59

species spread to other continents

Front 60

what changes took place in apes over the last 7 million years

Back 60

complex communication, use of tools, education, walk upright

Front 61

how did agriculture/tools affect human lifestyle

Back 61

leads to urbanization, massive populatoin rise, technology