Exam 4 Flashcards
(112 cards)
1
Q
What strata was left of the Devonian and the beginning of the Mississippian?
A
The remnants of the Acadian and Antler Mountains
2
Q
Mississippian Strata of North America
A
- Transition from shale to limestones
- The Great Mississippian Line Bank
3
Q
Great Mississippian Line Bank
A
- Shallow area on the sea floor deposited abundant limestones
- Analogous to the Great Bahama Bank
4
Q
Great Bahama Bank
A
- Dunes with wave ripples composed of individual calcite pebbles called Ooids
- An Ooid nucleus forms when part of a marine skeleton is encased by calcium carbonate in warm, agitated waters
- Abundance of echinoderm fragments like crinoids
5
Q
Mississippian Northeast US Strata
A
- Acadian mountains eroding to the west in the Catskill delta
–> New England and Newfoundland have exposed detrital, clastic sediments (Sandstones, Shales, Volcanics)
–> West Virginia and Pennsylvania (Pocono Group) have mountains with exposures of Mississippian sandstones and shales
6
Q
Mississippian Continental Interior Strata
A
- Montana and Wyoming (Madison Limestone) have Devonian limestone exposure
- Colorado and Arizona (Red Wall Limestone) have exposures in the Grand Canyon
- Missouri (Burlington Limestone) has lots of cave systems
- Kentucky (St. Genevieve Limestone) has the Mammoth Cave national park
7
Q
Demise of the Kaskaskia Cratonic Sequence
A
- A Karst is a type of landscape topography formed from the dissolution of soluble rocks such as limestone
- Karstification - processes that result in karst
–> Cave systems form from the dissolution of limestone - At the end of the Mississippian, limestone is dissolved to form vast cave systems
8
Q
Mississippian Paleoclimate
A
Presence of abundant limestones indicates a tropical climate with warm, fresh, shallow water with normal marine chemistry
9
Q
New Mississippian Life (Age of the Crinoids)
A
1) Reptiles
–> Weslothiana - Reptiolmorph amphibian
2) Blastoids (Pentremites) that were similar to Crinoids but have a distinctive head with feeding arms
3) Fenestrate Bryozoans (Archimedes) - Index fossil
–> Fan shaped colonial networks with a screw like shape in the center and adjacent fan frawns
4) Productid Brachiopods
–> Two shells and spines on the lower shell
5) Foraminiferas (Single-celled Protista) were sand sized
10
Q
Mississippian Plant life
A
Similar to the Devonian
11
Q
Mississippian Amphibians
A
Diversified
12
Q
Pennsylvanian Orogenies
A
- Alercynian-Alleghenian Oregeny (Northeastern US)
- Ouachita Orogeny (Southern US)
a. Ouachita Mountains
b. Marathon Mountains
13
Q
Pennsylvanian Cratonic Interior
A
Formed as a result of compression from orogenies
- Oklahoma Uplift
- Kanibab-Defiance-Zuni Uplifts
- Uncompahgre and Front Range Uplifts
14
Q
Laurasia
A
Late Paleozoic northern hemisphere continent comprised of NA, Greenland, Europe, and Asia
15
Q
Gondwanaland
A
Late Paleozoic southern hemisphere continent comprised of SA, Africa, India, Antarctica, Australia, New Zealand, and SE Asia
16
Q
Pennsylvanian Cratonic Sequence
A
Absaroska
17
Q
Cyclothems
A
Unique Sedimentary deposit usually following the formula:
Marine Shales
Coals ^
Non marine shales |
Fluvial Sandstones
Unconformity
18
Q
Gondwana’s Connection to sea levels
A
Ice sheet causes fluctuating sea levels as climate changes
19
Q
Eastern Cyclothems
A
Follow the pattern with well-developed coals
20
Q
Central Cyclothems
A
Have no coals
21
Q
Western Cyclothems
A
Form alternations of aeolian sandstone and limestones because of the drier climate
22
Q
Coal Swamps
A
Accumulation of plant material with wetlands produces coals
23
Q
Pennsylvanian Coal Swamp Analogs
A
- Dismal Swamp in NC
- Okefenokee swamp of SE Georgia
- Swamp of Southern Louisiana
24
Q
Coal Swamp Life
A
- Scale Trees (Lycopsids)
- Ferns (tree ferns and ground ferns)
- Amphibians
- Reptiles
- Insects
- Air-breathing mollusks (snails)
25
Pennsylvanian Climate
- Warm and humid
- Reptiles and amphibians present
- Trees with large cells indicate rapid growth
- Trees with no growth rings indicate aseasonality
26
Pennsylvanian Areas of Commercial Coals
1. Central portion of Appalachian region
2. Novasocia, Newbrunswick, PEI
27
Pennsylvanian Evaporite Deposits and Reefs
- Associated with cyclothems and SE US
- Paradox Basin - Thick successions of Gypsum, Halite, and Potash
Phyloid Algae - dominant reef building creature of the Pennsylvanian
28
Pennsylvanian New Life
1) Reptiles (Amniotic Eggs)
a. Hylonomus (Captorhinomorphs)
b. Synapsids (Mammal-like reptiles)
2) Land snails (air-breathing)
3) Fusilinids - Index fossils (Single-celled protozoan)
29
Pennsylvanian Environmental Considerations
- Orogenies caused sediment to pollute water, decreasing filter feeders
- Mollusks and prodkuctid brachiopods become more common
30
Pennsylvanian New Life (Age of the Cockroaches)
- Insects
- Amphibians (Labyrinthodonts)
- Vegetation – abundance of ferns
--> Lycopsids
a. Lepidodendran - stigmaria root shape
b. Sigillaria
--> Synopsids
a. Calamites
31
When did Pangea fully assemble?
The Permian era
32
Permian Paleoclimate
- Sea way closed between Laurasia and Gondwanaland
- Winds blowing from east to west
- Dry climate
33
Guadalupe Mountains
- During the Permian in west Texas and eastern New Mexico
- Permian Basin
- Basins, Reefs, Platforms
- Terminal Evaporites
34
Permian Basin
- Eastern shelf
- Midland basin
- Northwest shelf
- Central basin platform
- Delaware basin
- Diablo platform
- Marfa basin
35
Permian Basin Depositional Environment
- Basins
- Reefs (Mostly Catalina Sponges and Algae)
- Platform interior (Pisoids)
1) Shelf Crest
2) Lagoon
36
Pisoids
Super Ooids
37
Permian Terminal Evaporites
Alternation between Calcite and Gypsum
38
Permian Western U.S.
- Ancestral Rocky Mountains
- Western Edge of the craton
39
Permian Ancestral Rocky Mountains
- White-rimmed sandstone
- Aeolian dunes
40
Permain Western Edge
- Phosphorites deposited where the craton meets the seaway
- Trade winds cause upwelling of nutrient-rich seawater causing lots of life
- Phosphoria formation
41
Phosphorites
Original organic sediment from the tissue of organic matter
42
Phosphoria Formation
Black, muddy sediment
43
Gondwana Rock Succession
Used to prove Pangea and continental drift
1) Basaltic Tillites
a) Striated surfaces
b) Ice-rafted debris
2) Overlying coals
3) Non-marine sediments
4) Basalt flow cap
44
Unique attributes of Gondwanaland in the Permian
- Gondwana Rock Succession
- Glossopteris Flora
- Glossopteris Fauna
45
Permian Plants
- Paleophytic, Mesophytic, Cenophytic
- Conifers (Seed bearing)
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Paleophytic
Cambrian to early Permian
- Spore plants
47
Mesophytic
Mid Permian to late Cretaceous
- Seed plants
48
Cenophytic
Late Cretaceous to present
- Flowering plants
49
Permian Animals
- Ammonites are abundant
- Amphibians and reptiles expand and specialize
- Productid Brachiopods become abundant
- Insects diversify
- Fusilinids (Index) enlarge in the Permian
50
Dominant Permian predator in bodies of water
Eryops
51
Dominant Permian predator on land
Dimetradon
52
Late Permian Catastrophe - The Great Dying
- Trilobites and eurypterids go extinct
- Fusilinids go extinct
- Productid Brachiopods go extinct
- Bryozoans have a 79% loss
- Crinoids have a 98% loss
- Nautiloids have a 58% Loss
- Amminoids have a 98% loss
- Bivalves have a 58% loss
- Gastropods have a 98% loss
- Amphibians and reptiles have a 70% reduction
- Insects have a 33% reduction
53
Cause of the Great Dying
Most likely volcanics by the Siberian Traps
- Greenhouse gasses cause global warming and collapse of the food pyramid
54
Rifting of Pangea
Stage 1 - Gondwanaland and Laurasia, NA separates from SA and Africa
Stage 2 - Rifting of Gondwanaland, Antarctica and Australia
Stage 3 - Breakup of S. America and Africa
Stage 4 - Australia drifts, Greenland separates, India collides with South Asia
55
Triassic History Introduction
- Absaroka regression
- Deposits of sediments above sea level
- Red beds
56
Triassic Tectonics
Sonoma Orogeny - Western U.S.
57
Triassic Eastern U.S.
The Newark Group - fluvial and lacustrine
Intrusive Basalts within rift grabens
58
Triassic Western U.S.
Early Triassic - Moenkopi Formation
Late Triassic - Chinle Formation
59
Moenkopi Formation
Triassic, evaporites and fluvial deposits
60
Chinle Formation
- Triassic
- No marine interference
- Petrified forest national park
- Lots of Uranium
61
New Triassic Life
- Dinosaurs and mammals (Late)
- Scleractinian corals (modern)
- Lobsters and shrimp
- Protoavis (earliest bird?)
62
Triassic Peaks
- Plants
1) Chinle - cycads and conifers (dry climates)
2) Newark Group - ferns and rushes (wet climates)
- Reptiles
1) Thecodontians (Phytosaurs) - Individual teeth in sockets, dominant freshwater creature
2) Marine (Ichtyosaurs)
- Ammonoids and belemnites
63
NA Jurassic History
- Ancient Navajo Desert
- Zuni Cratonic Sequence (return of the epeiric sea)
- Nevadan Orogeny
64
Nevadan Orogeny
Jurassic, subducting crust to the east on the west coast
65
Jurassic Eastern U.S.
- Outcrops only found beneath the surface of the earth
- Lou Ann salt - dominated by Halite
- Smackover formation (Limestone composed of ooids)
66
Lou Ann Salt
- Jurassic
- Sea water flowed in to the rift valley of the ancestral gulf of Mexico
- Salt domes form from Lou Ann salt migrating upwards
- Oil and gas migrate upward
67
Jurassic Western U.S.
- Early Jurassic Navajo Sandstone - deposited via eolian processes
- Late Jurassic Zuni transgression, Sundance epeiric sea
68
New Life of the Jurassic (Mesozoic age of Dinosaurs)
- Archeacopteryx (first bird)
- Moths and flies
69
Peaks of the Jurassic
- Ammonites and belemnites
- Plants (cycads, tree ferns, gingkos)
- Reptiles
- Dinosaurs
70
Jurassic Reptiles
- Flying reptiles (Pterosaurs)
- Marine reptiles (Ichthyosaurs, Pleisosaurs, turtles)
- Freshwater reptiles (Crocodiles)
71
Jurassic Dinosaurs
- Saurischian (Lizard-hipped)
- Ornithischian (Bird-hipped)
72
Initial Recognition of the Cretaceous
White cliffs of Normandy
73
Cretaceous Dominant Characteristics
- Zuni Transgression (3rd of NA under water)
74
Mechanisms of the Zuni Transgression
- Pangea breakage
- Rapid seafloor spreading
75
Cretaceous Orogenies
- Sevier Orogeny in the West (late)
- Laramide Orogeny (early)
76
Sevier Orogeny
Started the transition to a lower subduction zone angle, causing mountain building inward
77
Laramide Orogeny
Nearly flat subduction zone which caused the crust to not melt, creating the present Rocky Mountains
78
Cretaceous Paleoclimate
- Warm and humid
- Fossil plants like magnolias, conifers, and ginkgos
- Dinosaur footprints
- Lack of glacial deposits
- Lack of evaporites
79
Cause of Cretaceous Climate
- Oceanic-Cratonic circulation via the Western interior seaway
- Cretaceous greenhouse caused by the volcanic gas release from seafloor spreading
80
Western Interior Seaway (Cretaceous)
- Chalks (Limestone made of cocaliths)
- Black Shales
- Coal-bearing clastic wedge
- Cyclothems
81
Cretaceous Black Shales
Lack of oxygen due to heat and the lack of polar ice caps to induce circulation
82
Cretaceous Atlantic Coast
- Erosion of the Appalachian Mountains
- About half of the mountains below sea level
- About 1000-2000m thick
83
Cretaceous Gulf Coast
- Bottom is limestone and conglomerates deposited by rivers and streams
- Transitions to marine shales and limestones
- Around 4000m thick, basin was subsiding at about twice the speed of the Atlantic coast
84
New Life in the Cretaceous
- Flowering Plants (Angiosperms)
- Bees
- New mammals (marsupials, insectivores)
85
Peaks and Advancements in the Cretaceous
- Dinosaurs
- Pterosaurs
- Plesiosaurs
- Ammonites
- Foraminifera
- Cocaliths (Algae)
- Bivalves (rudists - index fossil)
- Echinoderms - common in Cretaceous limestones
- Insects
86
Cretaceous Extinctions
- Dinosaurs
- Pterosaurs
- All marine reptiles (except turtles and crocs)
- Ammonites
- Rudists
87
Cretaceous Extinction Explanation
- Particles of the earths crust covered the globe causing a significant temperature increase followed by a global glaciation
- Chicxutub crator with Tektiles
- Indian Decan Traps
- Rifting of Pangea could've caused diseases to spread
88
Tertiary Tectonics
- Alpine-Himalayan Orogeny
- Circum-Pacific Orogeny (Ring of fire)
- Western NA
89
Circum-Pacific Orogeny
- Western pacific volcanic arc complexes
- Eastern pacific Andes Mountains
90
Western NA Tertiary Tectonics
- Laramide Orogeny
- Cordilleran Volcanism - Columbian river basalts
91
Cordilleran Volcanism
- Pacific Northwest had the Cascade Mountains
- Rocky Mountains had Yellowstone, the San Juan Mountains, and the San Francisco Mountains
- Basin and Range Province - Horsts and Grabens
- Colorado Plateau - Rivers erode as rock is uplifted
- Pacific Coast - Pacific plate sliding against NA plate
92
Tertiary Craton Interior
- Interior lowlands
- Zuni regression dries up the interior seaway
- Accretion wedge deposited off the Rocky Mountains into Central US
- Formed Ogallala aquifer
93
Teriary Gulf Coast
- Tejas Cratonic Sequence
- Tejas Transgression
- Sediment carried to the sea via the Mississippi river complex
- Lou Ann Salt domes push through the Paleogene and Neogene strata
- Black Shales got buried, creating oil and gas
94
Tertiary Paleoclimate
- Warm greenhouse climate persisted
- Middle Eocene introduces antarctic polar glaciation
- Early Miocene global warming followed by permanent glaciation of Antarctica
95
Paleogene New Life
- First primates
- Squirrel-like rodents
- Edentates
- Carnivores
96
Factors for Mammalian Success
- Endothermic
- Differentiated Teeth
- Insulated hair
- Live birth
97
Eocene New Life
- Whales and Porpoises
- Bats
- Mastodons
- Deer
- Giraffes, hyenas, camels
- Eohippus - first horse
98
Oligocene New Life
- Dog-like and cat-like animals
- Many modern taxa
99
Miocene New Life
Apes and Monkeys
100
Pliocene New Life
Hominids and Wooly Mammoths
101
Evidence for Continental Glaciers in the Quaternary
1) Erratic boulders carried by ice in the northern great plains
2) Striated/Polished rock surfaces
3) Till
4) U-Shaped Valleys
5) Planktic Foraminifera
102
Planktic Foraminifera in the Quaternary
A) Oxygen Isotopes - O16 is more present in warmer climate, O18 is more present in cooler climate
B) Coiling Direction - Right coil when water temp is above 8-10 degrees C, left coil when it's below 8-10 degrees C
103
Effects of Quaternary Continental Glaciation
1) Isostasy
2) Glacial Lakes
3) Sea level fluctuation
104
Isostasy
Ice sheets cause a depression in the asthenosphere which rebounds when the ice melts
105
Glacial Lakes
A) Depressions caused by ice
B) Lakes caused by ice dams
- Water melts off as the glacier accumulates and is stopped by the terminal moraine
C) Wind effects - Glacier cools air that flows down, depositing Loess (fine silt and clay)
106
Quaternary Ice Dam Lakes
1) Lake Agassiz - Canada
2) Lake Missoula - Montana (Channel Scabland)
107
Astronomical/Orbital Hypothesis
Milutin Milankovitch hypothesized the their are predictable changes in the earths tilt and orbit that cause climate to fluctuate in 100,000 year cycles. These factors are eccentricity, precession, and obliquity
108
Albedo
Proportion of sunlight reflected off of the surface, when sea levels fall more sunlight is reflected which cools the climate
109
The Climate Optimum
67,000 years ago the climate was perfectly equitable for life, which allowed major populations to become present
110
Medieval Climate Fluctuations
- Dark Ages -> Medieval Warm -> Little Ice Age
- During the warm medieval period, vikings explored overseas as the north sea opened
111
Pleistocene Extinctions
Extinction of large mammals largely contributed to by the rapidly changing climate and the expansion of the human species
112
Little Ice Age
1300 to 1850 AD
