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Geol 106 Exam 3
3rd Geol 106 Exam
110
Geology
Undergraduate 1
12/03/2012

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Cards

Term
What was the Marinoan Glaciation and what happened after it? (Ediacaran)
Definition
Last snowball event; rise in 02
Term
What were the 3 phases of the rise of oxygen after the Marinoan Glaciation? (Ediacaran)
Definition
1) Increase in SO4 in ocean
2) Oxygenation of deep ocean
3) Final rise to modern levels
Term
What is tied to the rise in oxygen after the Marinoan Glaciation? (Ediacaran)
Definition
Appearance of multi-cellular animals
Term
What were three attributes of the first Ediacaran multicellular animals? (Ediacaran)
Definition
1) Complex cell clusters
2) Soft-bodied Ediacaran Fauna
3) Carbonate skeletons/shells
Term
What is multicellularity? (Ediacaran)
Definition
Colonial, clonal, and multicellular aggregates
Term
Multicellularity requires:
What is the problem with multicellularity? (Ediacaran)
Definition
- Specialization and interdependence
- Overcoming 'cheating' cells
Term
What is Volvocine algae? (Ediacaran)
Definition
living group of eukaryotes that can be experimentally induced to switch from interdependent single cells to true multicellular aggregates
Term
What is the Doushantuo Formation, China, when does it represent, and what does it mean? (Ediacaran)
Definition
- Candidate fossil embryos, about 570 Ma
- Show Palintomy (increase in cell number but not size) which is not unique to animal embryos
- Positive evidence for complex cell aggregates
Term
What is the Lantian Assemblage (long description), and when does it represent? (Ediacaran)
Definition
- Carbonaceous imprints of large complex organsims found in deep water shales; clearly show specialization of body parts; not clear if animals or plants, but definitely multicellular eukaryotes
- about 630-610 Ma (poorly dated)
Term
What is the Ediacaran Fauna and when does it represent?
Definition
- global, soft-bodied, large, shallow and deep marine, variety of body plans, evolve
- about 579-541 Ma
Term
What are Rangeomorphs? (Ediacaran)
Definition
large organisms assembled from multiple, repeated parts that are themselves arranged in the same way from even smaller parts; thin sheets of cells over metabolically inert 'jelly'; osmotrophic (feed by absorbing nutrients passively)
Term
What are Sponges?
When was the earliest purported sponge fossils?
Definition
- multicellular aggregates, but no tissues or organs; contain spicules
- 760-550 Ma in Otavi and Nama groups in Namibia Africa; predate Marinoan Glaciation
Term
Explain the organization of bilaterian bodies.
Definition
Cells are organized in embryo by chemical gradients; triploblasty (3 layers); coelom provides a hydrostatic skeleton; triploblasty = bilateral symmetry
Term
What does Segmentation allow?
Definition
Allows the body to be divided into specialized modules.
Term
Where are Hox genes present?
Definition
In ALL bilaterian organisms (flat worms to humans)
Term
What is Kimberella evidence for?
Definition
Evidence of muscle-propelled movement, through-going gut, and internal body cavity.
Term
What happened during the Cambrian Substrate revolution?
Definition
Microbial mats were disturbed by burrowing.
Term
What is Trepichnus pedum?
Definition
Trace fossil that defines the base of the Cambrian Destruction of mats loosened sediment and released buried nutrients.
Term
Describe skeletonization.
Definition
Armor, claws/teeth, structural support, leverage; acquired independently in animal lineages that had already split in neoproterozoic; many different materials
Term
Describe Small Shelly Fauna.
Definition
Shells, spicules, sclerites; CaCO3 and CaPO4
Term
What as the Burgess Shale?
Definition
A Cambrian Lagerstaten.
Term
What is Cambrian characterized by?
Definition
Crown groups vs. Stem groups
Term
What came of the rise in marine diversity during the Cambrian?
Definition
Partly evolution of new types of animals and partly preservability of skeletons.
Term
What were established by the end of the Cambrian? (two)
Definition
All major phyla and classes (body plans appear early and remain stable).
Term
What happened to marine ecosystems during the Cambrian Explosion?
Definition
Major marine ecosystems established; reef-building, predation, burrowing
Term
What was Gondwana? (Early Paleozoic)
Definition
Southern Continents; Laurentia, Baltica, Siberia
Term
What happened in the Carbon cycle during the Early Paleozoic?
Definition
SPICE and Hirnantian positive excursions
Term
What were the main points of interest during the Ordovician?
Definition
"Paleozoic" style organisms; first animal traces on land by early Ordovician; first plant fragments and spores by middle Ordovician
Term
Describe the End-Ordivician mass extinction. (percent lost, etc)
Definition
about 49% genera lost; double hit (beginning and end of hirnantian); cool-water Hirnantian fauna spreads worldwide during event
Term
How did the Paleozoic fauna react during the Middle Paleozoic?
Definition
Rapid recovery after the End-Ordivican mass extinction; especially reefs (coral and stromatoporoid)
Term
What time period were shallow marine communities similar to?
Definition
Ordovician
Term
What are Gnathostomes and when did they appear?
Definition
Jawed vertebrates; appear by late silurian
Term
What are Placoderms?
Definition
Armor plated; teeth independently acquired from crown group gnathostomes
Term
What were jaws modified from?
Definition
gill arches (include Chondrichthyes)
Term
Fish with a swim-bladder/lung included:
Definition
Actinopterygii (ray-finned fish) and Sarcopterygii
Term
Define Stem Tetrapods.
Definition
From Sarcopterygians; modification of limbs and origin of flexible neck; Tiktaalik, Acanthostega, Ichthyostega; transition occurred in the late Devonian.
Term
Describe Arthropods on Land and when the earliest body fossil was.
Definition
Pre-adapted with external, waterproof skeleton and internal fertilization;spiracle adapted for breathing
Earliest body fossil = late silurian; firs insects in Early Devonian Rhynie Chert (another lagerstatten)
Term
Describe vascular plants.
Definition
Middle Silurian Cooksonia; Stomata and tracheids.
Term
Describe wood. (lignin and cellulose)
Definition
Cellulose = Tension
Lignin = Compression
Hard to break down; forests with canopy, understory, and ground cover by Middle Devonian.
Term
Describe seeds.
Definition
Late Devonian Elkinsia - heterospory, integument, pollen-recieving structure - freedom of plants from water for reproduction.
Term
Describe what happened in the Late Devonian mass extinction.
Definition
About 50% marine genera lost; End-Givetian, Lower and upper Kellwasser, and Hangenberg positive carbon Isotope excursions - each associated with sea level drops followed by flooding of anoxic waters on shallow marine shelves and epicontinetal seas; low latitude alpine glaciation in Appalachians.
Term
Describe the Late Paleozoic ice age.
Definition
Diamictites, dropstones, and striations on southern continents.
Term
What happened as plant life expanded? (wood, CO2, etc)
Definition
Consumed CO2 from atmosphere by making wood (buried rather than decayed) and increased weathering rates as root sytems evolved; left O2 as waste product in the atmosphere
Term
How can we tell what the CO2 and O2 levels were during the expansion of plant life?
Definition
Large arthropods sugget very high O2 levels, and density of plant stomata shows low CO2 levels.
Term
Where are the ancestral Rockies found?
Definition
western North America
Term
What does the Mid-Carboniferous unconformity show?
Definition
Separates Mississippian and Pennsylvanian
Term
When was the lowest point of global sea level in the Phanerozoic?
Definition
End-Permian
Term
Describe Marine life in the Carboniferous and Early/Middle Permian.
Definition
Stable and relatively low diversity in the Carboniferous, but increases in the Early and Middle Permian; no reefs early, but extensive reefs in Permian (sponges, bryozoans, and algae)
Term
When would the Amniota be found and what were they?
Definition
About 340 Ma
Claws or nails; no water-breathing larvae or embryonic stage; internal fertilization; egg
Term
When were the Sauropsids and Synapside? (two different times)
Definition
Sauropsids - 310 Ma
Synapsids - 320 Ma
Term
Describe the End-Permian mass extinction.
Definition
About 79% marine genera lost; Extinction pulse was <200 kyr but earth system remained perturbed for several Myr; coincide with the beginning of Siberian Traps; negative initial Carbon isotope excursion
Term
What are Siberian Traps?
Definition
Release of CO2 and SO2 caused weathering and acidification
Term
Who was affected by the End-Permian mass extinction?
Definition
hit calcified animals with poor abilities to adjust to high CO2 levels
Term
What were developing on the Atlantic Margin in North American during the Early Mesozoic?
Definition
Rift Valleys
Term
Where is the Sonoma Orogeny found and what is it?
Definition
Western North American,
Period of mountain building during the Permian/Triassic
Term
Describe the Early Triassic aftermath and how long was it?
Definition
End-permian extinction aftermath, continued perturbation of Carbon cycle for 4-5 Myr. Extreme global warmth; high weathering rates; anoxia in oceans; slow thermohaline circulation
Term
How did disaster fauna react to the Early Triassic aftermath of the End-Permian Extinction?
Definition
Adapted to low oxygen bottom water condition; Lystrosaurus on land
Term
What is caused ny an Anoxic ocean?
Definition
Slow thermohaline circulation, and requires elevated nutrient delivery system to oceans.
Term
What isotope in the Early Mesozoic indicates high weathering rates?
Definition
Sr
Term
Describe the Marine Realm during the early Mesozoic (Triassic)? What kinds of faunas were present? (describe reefs in the first part)
Definition
reefs re-evolve based on modern corals (scleractinian corals; photosymbionts); faunas include groups left form Paleozoic as well as roots of modern marine animals.
Term
What happened during the Synapsid evolution? What forms by the End of the Late Triassic?
Definition
Cynodonts - Secondary palate, specialized teeth, more advanced jaw, whiskers/hair
Mammalia formes by Late Triassic
Term
What happened during the Sauropsid evolution? What forms by the End of the Late Triassic?
Definition
Extensive diversification including marine and flying forms; archosaurs develop an erect limb orientation (crocodilians and dinosaurs)
Dinosaurs appear by the Late Triassic
Term
Describe the End-Triassic mass extinction.
Definition
About 55% of marine genera (mostly Paleozoic leftovers that never really did well in the Triassic); a sharp negative carbon excursion that coincides with the beginning of Central Atlantic Magmatic Province (CAMP)
Term
What was the Central Atlantic Magmatic Province?
Definition
Flood basalts and volcanism associated with the opening of the Atlantic Ocean.
Term
Which opened first - North or South Atlantic?
Definition
North before South
Term
Why does Geology 106 have nothing to with rocks, and instead teach us about microbiology? What are the only kinds of rocks that mater?
Definition
No frieking clue.
Oil rocks.
Term
Describe the Nevadan, Sevier, and Laramide Orogeny.
Definition
Nevadan - Jurassic
Sevier - Cretaceous; thick skinned
Laramide - beginning in the Jurassic-Creataceous, thick skinned
Term
What happened to the sea level in the Late mesozoic, and what does this mean?
Definition
Rising sea level, (Sundance sea and Western Interior Seaway) highest Phanerozoic sea level and elevated CO2
Term
What was the Zuni Sloss sequence?
Definition
Cretaceous, highest Phanerozoic sea level and elevated CO2
Term
What is Louann Salt and when/ where was it deposited?
Definition
Evaporite formation during the Mid-Jurassic in the Gulf of Mexico
Term
Please describe the Mesozoic Marine Revolution.
Definition
Started in Triassic but takes off in Jrassic/Cretaceous; appearance of numerous groups of predators that puncture or crush shells starts an arms race with prey items evolving stronger and more elaborate shells than in the Paleozoic and deeper burrowing rather than living on the sea floor.
Term
What originated in the Jurassic (Ocean) and what did it cause?
Definition
Origin of many Planktonic groups which resulted in chalk seas; new seas included Inoceramids - large flat clams that 'floated' on the sea floor and provided a hard substrate for communities of encrusters
Term
Describe the differences in reefs during the Jurassic and Cretaceous
Definition
Dominated by sponges in the Jurassic and Rudist Bivalves in the Cretaceous
Term
Describe Sauropsids.
Definition
Dinosaurs - dominant large terrestrial vertebrates (herbivores and carnivores)
tow main lineages: Saurischia (lizard-hipped) and Ornthischia (bird-hipped)
Term
Describe birds in the Late Jurassic and where they came from.
Definition
Archaeopteryx in Late Jurassic; descended from saurischia; have feathers; but no beak or fused breastbone and still a long tail
Term
Describe mammals in the Late Jurassic.
Definition
Juramia is earliest undisputed mammal; simpler stronger jaw, tooth replacement, prismatic enamel.
Term
What are the three still living lineages of mammals from the Late Jurassic?
Definition
Monotremata - milk but still lay eggs
Metatheria - marsupials
Eutheria - placental mammals
Term
Describe plants in the Late Jurassic.
Definition
Archaefructis in Early Cretaceous is earliest angiosperm; flowers, endosperm with seeds, fruit; Angiosperms are sister group of gymnosperms (conifers, cycads, ginkos)
Term
Describe the Cretaceous Terrestrial revolution.
Definition
Dinosaurs and gymnosperms dominated large organisms, but warm-blooded mammals and birds were all diversifying as small organisms.
Term
Describe the End-Cretaceous Impact.
Definition
10 km asteroid in Yucatan Peninsula; iridium layer, shocked quartz, microspherules; different expression of event at different distances from impact site.
Term
Describe the End-Cretaceous mass extinction. (organisms)
Definition
About 60% marine species including marine reptiles, ammonoids, rudists, inoceramids, and plankton. Deep ocean unscathed. Dinosaurs were lost, but organisms in water or burrows appeared to have fared better. Rapid recovery.
Term
Describe the immediate and long term consequences of the End-Cretaceous mass extinction.
Definition
Tsunami, ejecta blanket, and thermal pulse and appear to have affected North America (close to impact). Long term consequences include acid rain from CO2 and SO2 released from vaporized carbonate platforms as well as dust and soot. NO oceanic anoxia and NO strong global warming. Rapid recovery.
Term
What was the Laramide Orogeny and where was it found?
Definition
Period of mountain building in western North America.
Term
What happened due to the subduction of Farallon Plate in the Pacific Ocean?
Definition
Start of the San Andreas strike-slip (transform) fault; coincides with begging of Rio Grande rift and further extension of the Basin and Range of Western north America
Term
Describe temperatures and temperature patterns in the Early Cenozoic. (PETM)
Definition
Time of globally warm climate; PETM = extreme negative carbon isotope excursion; release of carbon <20 kyr, but return to pre-PETM levels took about 200 kyr; rise in temperature (5-8 C)
Term
What did the PETM during the Early Cenozoic cause in organisms?
Definition
Caused redistribution of terrestrial organisms (arrival of primates, ancient horses, and split-hoofed mammals in NOrth America) and extinction of archaic mammals
Term
What is PETM and what does it mean?
Definition
Paleocene-Eocene Thermal Maximum; The most extreme change in earth surface conditions during the Cenozoic era.
Term
What happened to mammals during the Early Cenozoic?
Definition
Radiation of mammals rooted in the Cretaceous (many lineages split before end-cretaceous extinction event); Paleocene had archaic forms (creodonts)
Term
What is the EECO?
Definition
A hypothermal caused by the PETM; Early Eocene Climatic Optimum
Term
What was the Cenozoic climate after the EECO?
Definition
general cooling trend (based on deep ocean water temperatures); cooling form Paleocene through Oligocene associated with decreasing CO2 but not much change in CO2 since beginning of Miocene
Term
Basin and Range during the Later Paleogene and Neogene extend what until present day?
Definition
western North America
Term
Describe the Himalaya and Tibetan Plateau during the late Paleogene and Neogene.
Definition
Collision of India and Asia starts 50 Ma; about 22 Ma Tibetan Plateau begins to rise; Sr isotopes indicate increase in global warming rates due to the rise of HImalaya and Tibet between 50 and 20 Ma. Coincides with global cooling trend and drop in CO2 levels
Term
What is associated with the climate during the Eocene-Oligocene?
Definition
Cooling trend during Eocene until deep ocean temp drop at E/O boundary; associated with the first ice sheet in Anarctica.
Term
Eocene-Oligocene cooling caused North America to Chnge how, and why?
Definition
Forest to parkland savannah; opening of oceanic passages (DRake passage/Tasmanian seaway) and initiation of Antarctic Circumpolar Current (ACC)
Term
Describe CO2 levels during the Miocene and what does this mean for grasslands?
Definition
CO2 dropped close to modern levels; expansion of grasslands; evidence for this expansion = phytoliths (silica grains in grass cells) and hypsodonty index (high crowned teeth that could eat this grass)
Term
Describe the grass that allowed for the expansion of grasslands.
Definition
Grew form base rather than tip; allowed herbivores to consume without destroying the plant.
Term
When was the closure of the Eastern Mediterranean?
Definition
about 15 Ma; trapping Black sea and Caspian Sea within Asian land mass.
Term
When was the closure of the Western Mediterranean? What does it lead to?
Definition
about 6-5 Ma; Messinian salinity Crisis.
Term
What is caused by the rise of the Isthmus of Panama during the Pliocene?
Definition
isolated Atlantic from Pacific and changed delivery of moisture and heat from equator to poles - with more moisture transported to North Atlantic, more snow could accumulate leading to ice-albedo feedback; cause for global cooling without change in CO2 levels.
Term
What caused global cooling in the Pliocene without changing CO2 levels?
Definition
Closing of the Isthmus of Panama, causing a seperation between the Atlantic and Pacific, ice-albedo feedback in moisture
Term
When was there an exchange of mammal faunas between the Americas?
Definition
2.5-3 Ma
Term
Describe the cyclicity of oxygen isotope values and noisiness from the Pliocene to present day.
Definition
2.6-1.2 Ma = about 40 kyr cyclicity
1.2-0 Ma = about 100 kyr cyclicity
Term
What indicates cooler temps and growth of ice sheets during the Quaternary?
Definition
Max oxygen isotope values indicate cooler temps AND growth of continental ice sheets
Term
Describe Ice ages in the Quaternary.
Definition
moraines (diamictite) found throughout northern hemisphere, indicating multiple periods of extensive ice sheet growth.
Term
Who was Louis Agassiz?
Definition
First to propose the earth had undergone an ice age.
Term
Describe the Milankovitch Orbital cycles.
Definition
eccentricity (circle or ellipse) (400 & 100 kyr), obliquity/tilt (40 kyr cycle), precession/orientaion of the rotational axis (20 kyr); confirmed using deep ocean cores in the 1970's
Term
When do Ice sheets grow the fastest?
Definition
Cool summers, Warm winters
Term
Describe the Inter-tropical Convergence zone. What does it cause?
Definition
Area of low pressure where warm air rises where sun heats the earth most; causes precipitation and directs winds towards the ITCZ; results in tropical monsoon
Term
What do tropical monsoons respond to? and why?
Definition
respond to 20 kyr precession cycle; tilt direction is more influential than distance from the sun.
Term
Describe the overall climate/ climate vaiability of the Quaternary and what does this mean for humans?
Definition
overall cold and high climate variability in a global context for the entire history of humans.
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