Geol 301 final Flashcards
(164 cards)
1
Q
What is Rodinia
A
The Middle to Late Proterozoic supercontinent
2
Q
When did Rodinia form
A
1.3 billion years ago
3
Q
when did Rodinia break up
A
around ~750 mya
4
Q
evidence for the break up of Rodinia
A
- development of passive margin strata around edges of Laurentia = formation of Pacific Ocean
- Grand Canyon rocks show deposition during the time in which Rodinia was rifting
5
Q
Time range of Proterozoic Eon
A
2.5 billion to 542 million years ago
6
Q
What happened during the proterozoic
A
- oxygenation of the atmosphere
- evolution of eukaryotes and multicellular organisms
7
Q
What was the Snowball Earth Theory
A
Earth was covered (almost) completely in ice, most extensive glaciation in the geologic record
8
Q
Evidence for Snowball Earth Theory
A
- neoproterozoic glacial deposits all over the world
- signatures of ice sheet movement
9
Q
What are some signatures of ice sheet movement
A
- U shaped valleys
- moraines
- kettle lakes
- cirque: bowl shaped depression at the head of a glacier
- Arete: sharp ridge between glacial valleys
- horn: erosion by several glaciers around a single peak
- calving: the process of icebergs breaking off of glaciers when they flow into a large body of water
- dropstones
- striations
- unsorted sediments
10
Q
When did snowball earth occur
A
- during the neoproterozoic
~640-710 mya - lasted about 10 million years each
11
Q
cirque
A
bowl shaped depression at the head of a glacier
12
Q
arete
A
sharp ridge between glacial valleys
13
Q
horn
A
erosion by several glaciers around a single peak
14
Q
calving
A
the process of icebergs breaking off of glaciers when they flow into a large body of water
15
Q
dropstones
A
stones that were incorporated into a glacier/iceberg when it claves but are dropped out some distance away from the shoreline as the iceberg melts
16
Q
How do you unfreeze a planet
A
- limited weathering led to build up of atmospheric CO2 -> no Ca to turn CO2 into calcite -> global warming
17
Q
Evidence of Basal Metazoans
A
- body fossils
- trace fossils
- embryo fossils
- Molecular clock (DNA estimates)
- biomarkers slightly predate the ediacarian fauna (earliest multicellular life)
18
Q
what were some characteristics of early multicellular animals
A
- sessile lifestyle
- multicellular complexes
- few cell types
- lack variation in tissue or organs
19
Q
What can sponges tell us about the evolution of multicellularity in the late Proterozoic
A
a dramatic diversification of animals occurred rapidly
20
Q
Evidence for sea level rise in the Cambrian
A
Carbonates above a transgressive sandstone, suggest transgression and marine flooding of NA
21
Q
what is the Cambrian explosion
A
“Evolutionary experimentation”
- sudden and expansive diversification of animals
- sudden appearance of hard parts
- rapid evolution of skeletonization and new body plans
22
Q
what were the Tommotian Fauna
A
- small (mm) shells that span the Precambrian - Cambrian transition
- the first major appearance of skeletal material
- shells from numerous groups. Many named for their shape (“from taxa”)
- tiny carbonate and phosphate shells
23
Q
Age of the Tommotian Fauna
A
~540-528 mya
24
Q
what is the significance of the tommotian fauna
A
the first appearance of mineralized taxa = brachiopods, trilobites, archaeocyathids, molluscs, echinoderms
25
What are some typical types of Cambrian fossils
- Trilobites
- inarticulate brachiopods
- echinoderms
- monoplacophoran mollusks
- stromatolites
26
What were Cambrian invertebrates like in terms of relative diversity and the phyla that were present compared to modern organisms?
- many different body plans
- bizarre classes of familiar phyla (each had a few species and genera)
- early echinoderms, likely related to crinoids
27
what is the significance of the Burgess Shale Fauna
- deep water setting with organic, low O2 sediments
- preserved soft bodied organisms (Pikaia, Onychophorans)
28
What is the significance of the Chengjiang fauna
- preservation of soft-bodied creatures (Corals, predatory worms, soft-bodied arthropods, anomalocarids)
29
What are Stromatolites
- finely laminated cyanobacterial mats that secrete calcite and climb to stay on top
30
What are Thrombolites
- non-layered, clotted/clustered sedimentary formations generated by cyanobacteria
31
Baltica
Northern Europe
32
Laurentia
North America
33
Gondwanaland
South America, Africa, Arabia, India, Australia, and Antarctica
34
What is the significance of stromatolites and thrombolites
- contain microbes from 500mya
- help with understanding origin and evolution of life
35
Archeocyathids
- early Cambrian reefs
- suspension feeders
- probably sponges
- built large reefs during early cambrian, extinct by middle cambrian
- cemented by cyanobacterial mats and other organisms that secreted calcite
36
What were some of the first chordate (early fish) ancestors in the cambrian
conodont (just found teeth fossils at first)
37
What was the Taconic Orogeny
- mountain building event that lead to the building of mountains along the north east
- Laurentia collided with a volcanic island arc, then Baltica
38
what caused the Taconic Orogeny
collision of ancestral North American plate with island arc (accretionary wedge crunch upward)
39
What is a foreland basin
- the downwarping of lithosphere behind an actively forming mountain chain
40
How does a foreland basin form
Subduction of oceanic crust under continental crust, magma pushes up through cc by subduction zone, cc warps up where magma is and down inland,
41
What is a molasse
terrestrial (river deposited) gravels and coarse sands representing collision orogenic clastics
42
what is a flysch
a coarsening upward sequence of sedimentary rocks that form in a foreland basin during an orogeny. Deeper water shales and shelf deposits are overlain by shoreline and terrestrial sediments as the basin fills with sediments
42
What are ophiolites
the remnants of very metamorphosed seafloor pinched up along suture
43
What factors drove diversification in the Ordovician
1. high sea level and large epicontinental seas during much of the Ordovician
2. restricted land, archipelagos (island chains) create a lot of shallow marine environments
3. intense magmatic and tectonic activity
4. strong climatic zonation = biogeographic differentiation
5. asteroid bombardment
44
What is ecological tiering
- organisms growing taller and burrowing deeper
- diversification and specialization to meet feeding needs
45
What were the primary reef builders in the Ordovician
- coral-strome reefs
- tabulate corals
- stromatoporoid
- rugose corals
46
What were stromatoporoids
calcified sponges
47
What is thought to be the primary cause of the Ordovician Mass Extinction (2nd largest)
- ice age
- global cooling
- sea level drop
48
Main types of species affected by the Ordovician Mass Extinction
warm adapted taxa
49
What were the primary reef builders during the Silurian-Devonian
- coral-strome reefs
50
What were the dominant invertebrate predators during the Silurian-Devonian
Eurypterids and ammonoids
51
What were the early fish like in the Ordovician
- jawless
- boney armor
- bottom dwellers
52
What type of animal were conodonts
primitive craniates
- modern lamprey
53
when did jawed fish evolve
Evolved in the latest Silurian to Early Devonian
54
What were some of the major groups of jawed fish
- acanthodians (small)
- sharks
- ray finned fish
- placoderms
55
How did jaws evolve in fish
Food filters were modified to form gills, first gill arch became upper and lower jaws, second-gill arch moved forward to brace jaws
56
From what body part did fish jaws evolve
skeletal rods
57
when did terrestrial plants first appear
Silurian
58
when did amphibians first appear
Devonian
59
What type of plants were the first plants
non-vascular plants (mosses, liverworts, hornworts)
- spore-bearing
60
How do spore plants (the first plants) reproduce
by releasing spores, or small cells, that germinate
61
What were some of the first vascular plants
- cooksonia
- rhynia
62
How did vascular plants reproduce
- seeds!
63
what type of plants were the lycopods
- non vascular
- club mosses
- their forests formed many early coal swamps
64
when did seed plants evolve
Devonian
65
what were some advantages of seeds compared to spores
- allowed plants to migrate on land
- no longer needed wet environment
- easy dispersion
- food store for seed
- seed only opens when conditions are good
66
Avalonia
Parts of North America, British islands, Belgium, and Germany
67
Euramerica
Laurentia, Baltica, US, parts of Canada, Newfoundland, southern Ireland, Wales, England, and Belgium
68
What caused the Acadian Orogeny in the Devonian
double collision of
- Northern Laurentia and Baltica
and
- Southern Laurentia and Avalonia
69
What caused the Antler Orogeny in the Devonian
- island arc colliding with NA plate
70
What geological locations were affected by the Antler Orogeny
- Klamath Mountains
- Sierra-Nevada Mountains
- western NA (first episode of mountain building here)
71
What caused the ice ages at the end of the Devonian
- spread of forests
- increased weathering
reduced atmospheric CO2
72
How is the carboniferous period subdivided
Mississippian and Pennsylvanian
73
characteristic sediments of the Mississippian
abundant warm water limestones
74
characteristic sediments of the Pennsylvanian
abundant swampy lowlands, glaciation
75
time range of the mississippian
360-320 mya
76
time range of the pennsylvanian
320-300 mya
77
Calcite vs Aragonite
Calcite
- forms as a trigonal crystal of CaCO3
- more stable at lower Mg:Ca ratios
Aragonite
- forms as an orthorhombic crystal of CaCO3
- more stable in higher Mg:Ca ratio (typical of times with slower seafloor spreading rates and less MORs)
78
Typical conditions for increased Aragonite
- higher Mg:Ca
- slow seafloor spreading rates
- less MORs
79
gymnosperms
- "naked seed plants" (seeds are not enclosed in ovaries)
- formed woodlands
- the first conifers
- unfertilized seeds called "ovules"
- pollen grains enter through the opening
80
what are some examples of gymnosperms
- seed ferns
- ginkgos
- cycads
81
angiosperms
- flowering plants
- seeds are protected by fruit
82
when did winged insects first evolve
Mississippian
83
Why were some carboniferous insects larger than modern forms
- more O2 in the atmosphere
84
when did reptiles first appear
lower pennsylvanian strata
85
what is a major difference between reptiles and amphibians in terms of the egg that each type of animal has
reptiles developed in an amniotic egg (yolk sac, waste, sac, amnion inside outer shell)
86
what are some differences between amphibians and reptiles
amphibians
- used to be larger and slower
- required aquatic habitats and shade
reptiles
- minor skeletal differences
- develop in an amniotic egg
- live and reproduce away from water
- strong jaws, slicing teeth
- faster and more agile
87
what is the significance of the peleycosaurs
- play an important role in the rise to mammals
- earliest known synapsids
- transitional groups to mammals in both form and function
88
what were therapsids
- similar to mammals (evolved to them)
- transition to legs under the body
- complex jaws and teeth
- endothermic
89
What were Pelcosaurs
- fin-backed reptiles
- dominant predators
90
What is Pangea
supercontinent
91
when did Pangea form
Permian
92
When was the Alleghenian Orogeny
Pennsylvanian
93
what caused the Alleghenian Orogeny
- eastern US
- collision of Euroamerica (Laurentia and Baltica) with Gondwanaland
- Appalachian mountains
94
how do the Ouachita mountains have to do with the Alleghenian Orogeny
- westward continuation of the Appalachians
- fold and thrust belt of offshore deposits
95
What types of rocks typify the Delaware Basin
- carbonate and evaporite deposition
- organic-rich sediments with salt
96
where is the delaware basin
texas and new mexico
97
what is the economic importance of the delaware basin
the Delaware basin is a significant petroleum source
98
What is a cyclothem
cycles in coal beds that contain marine sediments
99
What is the meaning of Paleozoic
Old life
100
what is the menaing of mesozoic
middle life
101
what are the Paleozoic and Mesozoic separated by
The permo-triassic extinction ~250 mya
102
what are the different time periods of the Mesozoic and their time frames
Triassic (251 - 202 mya), Jurassic (202 - 145 mya),
Cretaceous (145 - 66 mya)
103
When did Pangea start to rift apart
middle triassic
104
What is the Tethys seaway
- formed between NA and SA/Africa
- site of medditeranean and gulf of mexico
105
What are some differences between major types of marine invertebrates that dominated in the Paleozoic compared to the Mesozoic
no more fusulinids, lacy bryozoans, rugose corals, trilobites
abundant mollusks, stromatolites, bivalves, sea urchins, reefs, ammonites
106
What are ammonites
little squid like guys
107
During what time periods are ammonites important fossils for biostratigraphy
mesozoic
108
Which line of early amniotes led to mammals
synapsidia
109
Which line of early amniotes led to dinosaurs
diapsids
110
When did marine reptiles first evolve (euryapsida)
Triassic-Cretaceous
111
what are some characteristics of early marine reptiles like placodonts, plesiosaurs, and ichthyosaurs
- one high temporal fenestra
- evolved from land reptiles
111
Placodonts
- blunt tooth shell crushers
- broad armored bodies
- superficially resemble turtles
- shallow nearshore habitats
112
Nothosaurs
- seal like lifestyle
- caught food in water but hung out on land
~3 meters long
- webbed feet
113
Plesiosaurs
- evolved from nothosaurs
- top marine predator of the mesozoic
- up to 12 m long
- triassic to cretaceous
- fully marine
- long necks for darting after fish
- limbs modified into flippers
- bore live young
114
Ichthyosaur
- dolphin like lizards
- bore live young
- large eyes adapted for deep water depths (low light)
- triassic to cretaceous
115
What type of animals were the archosaurs (dinosauromorphs)
diapsida
- permian-triassic dinosaur ancestors
116
what is the significance of archosaurs
- began upright posture (limbs under body)
- serrated teeth
- 4 chambered heart
117
what caused the end Triassic mass extinction
- global warming
- volcanic activity associated with rifting led to high volumes of CO2
- disrupted oceanic currents
118
When did dinosaurs first evolve
Triassic, Mesozoic
119
What is the difference between lizard hipped and bird hipped
lizard hipped "saurischia"
- led to the birds
- large herbivores
- carnivores
bird hipped "ornithischia"
- herbivores
120
Examples of lizard-hipped dinos (sauricia)
- theropods (bipedal carnivores)
- sauropods (large herbivores)
- led to the birds
121
examples of bird-hipped dinos (ornithischians)
- bipedal or quadrupedal
- duck-billed hadrosaurs
- horned ceratopsians
- armored stegosaurus
- ankylosaurs
122
when did birds evolve from sauricians
jurassic
123
sauropods
largest of all dinosaurs
124
what are some lines of evidence that at least some dinos were warm blooded
- too active to maintian body if they were cold blooded
- sharp slicing teeth
- greater endurance and tolerance to cooler temperatures
- dino proportions of predator to prey are similar to mammals
- lots of bone marrow
- brooding eggs
125
besides warm bloodedness, what were other ways raptor dinos were similar to birds
- brooding
- feathers for insulation
- three toes foot
- wishbone
- hollow bones
- brooding of eggs
- feathers in some
126
when did primitive feathers first evolve in some dinosaurs
jurassic
127
what was the primary purpose of feathers for dinosaurs
insulation
128
what is the significance of the archeopteryx fossil
- missing link between birds and dinos
129
what are some characteristics of the Archaeopteryx
- feathered
- breastbone
- jaws had teeth like dinosaurs
130
what time period is the Archaeopteryx from
mid jurassic
131
what is the time period of the sonoma orogeny
Permian-triassic
132
what caused the sonoma orogeny
volcanic arc collisions along the western US
133
what mountain ranges were involved in the Sonoma orogeny, and what is influencing their growth
The Sierras, continued subduction, volcanism further inland
134
What was the sundance sea
- flooded western US by the pacific
- significant molasse
- lots of dinos burried during flood events
- late jurassic
135
what was the western interior seaway
seaway from the atlantic, up through NA to the arctic during high sea level
- shallow
- organic and fossil rich marine deposits
136
what is unique about the morrison formation in colorado and utah
137
what were rudist bivalves during the cretaceous
bivalve mollusks that appear like corals
- predators
138
What are the Nevadan, Sevier, and Laramide Orogenies
mountain building events in the western US
- subduction angle decreased over time
139
Formation of the Gulf of Mexico
- jurassic
- passive margin
- salt deposition on stretched crust
140
When do angiosperms appear
cretaceous
141
when did true mammals first evolve and from what group
Cretaceous, from the therapsids
142
What are some characteristics of mammals that distinguish them from reptiles
- legs under body
- complex jaw
- differentiated teeth
- hair
- probably endothermic
143
Characteristics of monotremes
- mammals that lay eggs
- warm blood
- hair
- nurse young
- cloaca
- low metabolic rate
144
characteristics of marsupials
- born prematurely and finish maturing in a pouch
- dominant in australia
145
placentals
- Afrotheria
- Xenarthra
- laurasiatheria
- euarchontoglires
146
afrotheria
Africa: aardvark, elephant, hyraxes, seacows
147
xenarthra
South American: anteaters, sloths, armadillo
148
Laurasiatheria
North America, Europe, Asia: insectivores, bats, whales, ungulates, carnivores
149
euarchontonglires
Europe: rodents, rabbits, primates
150
what drove the early evolution of horses
shift from life in forest to life on open grasslands
- Miocene
151
when and from what did whales evolve
bear like terrestrial hooved mammals (mesonychids)
- paleogene
152
when did primates first evolve
Eocene
153
What is the significance of C4 vs C3 grasses
- C4 plants grow in drier climate with pronounced summer, more silica
- C3 grown in more uniform climate (warmer)
154
Tectonic Ice age causes
cooling, caused by disrupted water mixing
155
when did the apes first evolve
oligocene - miocene
156
proconsul
split from old world monkeys
156
earliest human ancestor
Sahelanthropus
157
AUstralopithecines
immediate ancestor of our genus homo
158
Australopithecus afarensis
lucy
158
Neanderthals
159
homo habilis
stone tools
160
