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H122 Historical Geography
Final Exam
209
Geology
Undergraduate 3
03/11/2006

Additional Geology Flashcards

 


 

Cards

Term
Sequence Stratigraphy
Definition
- using unconformity-banded stratigraphic packages (sequences) for correlation

- sequences are due to local (basinwide) or eustatic (worldwide) changes of sea level
Term
Principle of Cross-Cutting Relationships
Definition
Faults are younger than the rocks they cut
Term
Principle of Inclusions & Components
Definition
Inclusions and components are older than the rocks in which they occur.
Term
James Hutton's Concepts:
Definition
1. Cross-cutting relationships
2. Included fragments (components)
3. Unconformities
Term
Characteristics of Metamorphic Rocks
Definition
- Banding (non-flat layers) and aligned minerals or intergrown crystals
- Shiny surface
- Ringing sound when struck
Term
Stratigraphy
Definition
- Study of layered rocks
Term
Correlation
Definition
Matching of stratigraphic units from one place to another by any characteristc

-lithostratigraphy
-color
-unconformities
-geophysical characteristics (radioactivity, etc.)
Term
Lithostratigraphy
Definition
-Correlation of rock units based on what they look like (lithology)
Term
Formation
Definition
- Basic unit of lithostratigraphy
- Clearly identifiable, mappable, body of rock.
Term
Biostratigraphy
Definition
- Based on Smith's concept of biotic succession.

- Stratigraphic ranges of guide fossils used to tell relative time.

- Need species ranges: time of appearance evolution and extinction.
Term
Zone
Definition
- Basic unit of Biostratigraphy

- A stratigraphic interval characterized by a particular set of fossils
Term
Types of fossil preservation (6)
Definition
1. Replacement - dissolved chemicals replace minerals in fossil.
2. Permineralization - fossilization of wood.
3. Carbonization - changed to carbon through distillation (heating, burial).
4. Unaltered - w/o change.
5. Moldic - fossil same as matrix.
6. Recrystallization - from unstable to stable.
Term
Adaptation
Definition
- Changes in parts (organs, limbs) help to guide the course of evolution.

- Most changes (mutations) are detrimental or neutral.

- Specialized feature of an organism (a positive change) which helps the organism to survive in an ecological niche (not necessarily optimally, constrained by evolutionary heritage)
Term
What can body fossils be used for?
Definition
- Correlation: tracing time equivilant strata.

- Paleoecology, paleoclimatology, paleogeography, paleoenvironments.

- Tracing evolution.
Term
Trace fossils info:
Definition
- Unlike body fossils, trace fossils cannot be moved so they are able to tell us exact locations of organisms.

- Provide information about the BEHAVIOR of organisms.
Term
How are body fossils classified?
Definition
- According to the rules of biological taxonomy.

- Kingdom, Phylum, Class, Order, Family, Genus, Species.
Term
How are trace fossils classified?
Definition
Ichno = trace

- According to ichnospecies, ichnogenera (plus, categories like walking, burrowing, etc.)
Term
Biological Species Concept
Definition
- Basic unit of taxonomy: Group of organisms that can mate successfully and produce fertile offspring
Term
How can you determine if long-dead organisms interbred?
Definition
You can't.

That is why paleontologist's have the paleontological species concept: Define spcies on the basis of morphologic similarities and differences.
Term
Evolution
Definition
- A change over time (in organisms).

1. Microevolution.
2. Macroevolution.

- does not always proceed from simple to complex, just change.

horses - complex to simple;
cephalopods - simple to complex
Term
Macroevolution
Definition
A change on the species level through time.
Term
Ontogeny
Definition
Change an individual organism goes through in its life.
Term
Evidence of Evolution (According to Darwin) (3):
Definition
1. Embryology;
2. Homologous structures;
3. Vestigial Structures.
Term
Embryology
Definition
The similarity of the embryos of vertebrate animals in their early stages.
Term
Homologous Structures
Definition
Desendant structures derived from the same ancestral one.

i.e forelimbs of vertebrate animnals (human arm, horse leg, bird wing, etc) have identical bones, in same order, but different shapes adapted for different things.
Term
Analogous Structures
Definition
Structures having the same function but not derived from shared ancestry, but rather from ecological pressure.

i.e birds and bees both have wings.
Term
Vestigial Structures
Definition
Small, useless structures that are in the process of disappearing.

i.e horses with extra toes, whale pelvic bones
Term
Evidence for evolution (after Darwin):
Definition
1. Genetics;
2. Molecular Information.
Term
Mechanisms of Evolution (Darwin):
Definition
1. Natural Selection;
2. Adaptation.
Term
Natural Selection
Definition
Weeds out individuals that cannot successfully survive to reproductive age.
Term
How do evolutionary changes arise and accumulate?
Definition
- Genetics.

- changes are passed from parent to offspring thru genetics.

- changes arise through genetic recomninations and mutations (inexact replicas in DNA).
Term
Cladogram
Definition
Branching diagram; evolutionary hypothesis in which taxa are grouped based on evidence of common ancestry (shared, derived characters).
Term
Convergence/Homoplasy
Definition
Species can evolve only once, but similar structures can evolve more than once in repsonse to similar ecological pressures.

i.e birds and bees have wings.
Term
How fast does macroevolution occur?
Definition
Two theories:

1) Phyletic gradualism: gradually, the result of a slow acumulation of changes.

2) Punctuated equilibrium: rapidly, followed by along interval or morphological stasis.
Term
Mass extinction
Definition
When numerous species all go extinct within a short interval of geologic time.

- due to some major environmental perturbation.
Term
Extinction
Definition
Annihilation of all individuals of a species.
Term
Adaptive Radiation
Definition
Rapid evolution of a group of organisms. (transistion of air-breathing fish to amphibians)

Result of:

1) Adaptive breakthrough;
2) Result of extiction event;
3) Following the development of new habitats.
Term
Punctuated Equilibrium
Definition
Said stratigraphic record was complete, so if you didn't see an intermediate it didn't exist.

BUT gradualism does occur and the stratigraphic record is broken (but not everywhere).
Term
Phyletic Gradualism
Definition
Assumed stratigraphic record was broken, which caused gaps in evolutionary lineages.

- Archaeopoteryx discovery showed intermediates do exist.
Term
How does an organism become a body fossil?
Definition
- death or shedding of parts;
- survive scavenging and decay;
- survive further desication by weather, burial in sediment, reworking of sediment, possible dissolution by water, lithification, possible further dissolution and metamorphism
Term
Taphonomy
Definition
The study of the process of fossilization.
Term
Biomarkers
Definition
Chemical fossils:

- chemical breakdown products of organic tissues.
Term
Trace fossils
Definition
Evidence of activity of organisms (track marks, burrows, bitemarks, etc.)
Term
Body Fossils
Definition
Direct or altered remains of an organism.
Term
Paleontology
Definition
The study of fossils.
Term
What is a fossil?
Definition
Evidence of ancient life (older than 11,000 years is considered ancient).

Does not have to be rock. Amber works too, for example.
Term
Half-life
Definition
time it takes for half of the material to decay.
Term
Radiometric dating
Definition
Absolute ages of rocks assessed using radioactive isotopes;

- radioactive isotopes have been decaying at a fixed rate since rocks were formed

- as the parent material decays a daughter material accumulates in rock
Term
Chronostratigraphic (Time-Stratigraphic) Units
Definition
Time Unit: abstract concept.

Time-Stratigraphic Unit: Tangible unit of strata.

All the strata deposited during a particular interval of time.
Term
How much time is missing (Disconformity)?
Definition
Very small in geologic terms. Only a couple million years.

- strata above and below the unconformity show little evidence of a gap.


- we usually know there's a time gap b/c we're missing one or more fossil zones.
Term
How much time is missing (Angular Unconformity)?
Definition
Strata have been folded or tilted, then eroded and sediment placed on top.

- himalayas are about 35 m.a old. takes about 35-40 m.a to fold, then another 40 to erode.
Term
How much time is missing (Non-Conformity)?
Definition
Batholiths and magma chambers are usually around 10km below the surface.

- About 40 million years or more to erode away 10 km of igneous rock.
Term
Disconformity
Definition
Strata above and below the unconformity are parallel to each other.
Term
Angular Unconformity
Definition
Unconformity strata are at an angle to surrounding sedimentary strata.
Term
Non-Conformity
Definition
Sedimentary strata are layered on top of igneous or metamorphic rock.
Term
Unconformites
Definition
A break in the stratigraphic record due to erosion or non-deposition of strata:

1. non-conformity;
2. angular unconformity;
3. disconformity.
Term
Principle of Biotic Succession
Definition
Fossil organisms succeed one another stratigraphically in a definite and determinable order

- due to the non-repeatable nature of biological evolution and extinction.
Term
Principal of Original Lateral Continuity
Definition
Strata originally extended in all directions until they thinned out or terminated against the edges of their basin of deposition.

- b/c of their original, continuous, tabular shapes, strata can today be correlated across valleys, etc where erosion or faulting has occured.
Term
Principle of Original Horizontality
Definition
Sedimentary strata were originally deposited in a nearly horizontal position

- if not found that way there were probably moved.
Term
Principle of Superposition
Definition
In an undisturbed succession of rocks, older beds occur below younger beds.
Term
Nicholas Steno's Principals
Definition
1. superposition;
2. original horizontality;
3. lateral continuity.
Term
Characteristics of Sedimentary Rocks
Definition
Distinct grains, bedding, possible fossils
Term
Classifications of Metamorphic Rocks
Definition
1. foliated or
2. not
Term
Characteristics of Igneous Rocks
Definition
interlocking crystals, glass
Term
Compaction and dewatering
Definition
compression of deep lying sediments by the weight of overlying sediments reduces pore spaces and squeezes water out
Term
How are sediments turned into rocks
Definition
Lithification:

1. compaction and dewatering;
2. cementation.
Term
Breccia
Definition
siliclastic w/ angular grains
Term
Conglomerate
Definition
Siliclastic with rounded grains
Term
Siliclastic rocks
Definition
loose particles resulting from weathering of silica-bearing rocks at the earths' surface
Term
Two ways to classify rocks
Definition
1. descriptive: using fabric and compositon;
2. genetic: igneous, metamorphic, or sedimentary.
Term
Uniformitarianism
Definition
The way Earth's systems work is the way they have always worked.
Term
Microevolution
Definition
Changes that occur as parents pass on their genetic characteristics to offspring.
Term
To determine if rock beds are disturbed (5)
Definition
- fault?
- similar rocks above and below
- go to another location and see similar rocks in same succession?
- bending of strata?
- if they are flat-lined they might be okay, but sometimes rocks can be flipped entirely upside down (Recumbent folding)
Term
Cementation
Definition
Chemicals (calcium carbonate, silica, iron oxide) are precipitated from water, fill up pore spaces, and grains are bound together.
Term
Conditions conducive to fossilization:
Definition
1. Anoxic
2. High salinity
3. Extreme dryness or cold
4. Enclosure in substance such as ice or sap (anoxic)
5. Rapid burial and/pr sedimentation (anoxic)
Term
Sandstone represents
Definition
Non-marine deposits showing low sea level
Term
Transgression
Definition
rise in relative sea level
Term
Regression
Definition
Drop in relative sea level
Term
How do sea level changes affect the sedimentary record (Transgression)?
Definition
Facies shift toward land
Term
How do sea level changes affect sedimentary record (Regression)?
Definition
Facies shift toward ocean
Term
To apply Walther's Law...
Definition
There must be no significant break in the sedimentary succesion
Term
Facies
Definition
Various meanings

- usually refers to the appearance of rock (lithology, color, fossils, etc.)
Term
Lithofacies
Definition
One part of a sedimentary body (rock or sediment) compared to others of equivilant age.

- essentially, the sediment deposited in one depositional environment.

* A FORMATION *
Term
How do we interpret lateral relationships of facies?
Definition
Walther's Law
Term
Walther's Law:
Definition
Vertically superimposed facies in the sedimentary record were laterally adjacent to eachother at the time of deposition.
Term
Limestone represents
Definition
Marine deposits, showing high sea level.
Term
Interpreting a stratigraphic section:
Definition
In a transgression, strata fining upwards. A regression, strata fining downwards.
Term
What tools can we use to interpret depositional environments?
Definition
1. Walther's Law
2. Presence of fossils
3. Types of sedimentary rocks
4. Sedimentary structures
Term
How can the presence of fossils help us interpret depositional environments?
Definition
Creatures are very sensitive indicators of the environment
Term
How can types of sedimentary rocks help us interpret depositional environments?
Definition
Carbonate rocks (such as limestone) are formed almost exclusively in warm, shallow, marine environments.

Siltzied grains often deposit in deep water.
Term
What sedimentary structures help us interpret depositional environments?
Definition
Ripple marks, cross-bedding, stromatalites, mudcrack, raindrops, etc.
Term
Horizontal bedding
Definition
Flat surfaces; oldest at bottom

Caused by short lapses in sedimentation or changes in grain size or composition (changes in tide).
Term
Cross-bedding
Definition
Strata are inclined at different angles (caused by changes in current diretion or strength).
Term
Ripple marks
Definition
Bedding planes rippled by currents (wind or water).

1) asymetrical: rivers, beaches, deserts, down-wind side is shorter
2) symetrical: current moving back and forth (ossilation), shallow water, the reflection of waves, pond edges, swamp edges, tidal flat environments
Term
Geopetal structure
Definition
any sedimentary struture that shows stratigraphic-up (younging) direction

* remember: this is how we can test whether strata are in correct succession or not
Term
Graded-bedding as a geopetal structure:
Definition
Vertical change from large to small grain size (due to one rapid depositional event); current started out strong, then disipated - coarser grains at bottom, finner at top.

Tend to occur at river basins (esp. ones tht tend to flood), undersea landslindes, continental rise (turbidites, etc. )
Term
Mudcracks and raindrop impressions as geopetal structures:
Definition
Mudcracks: caused by drying of mud. Vs point to the center of the earth, and are concave to the sky.

Raindrop impressions: caused by rain falling on wet mud. The small craters of raindrop impressions are also concave to the sky.
Term
Concretions
Definition
Rounded masses formed around organic matter.

- environments: aqueous, usually marine.
- microorganisms perserved in concretions show us how many organisms (except for bones, teeth, shells) became fossilized.
- some bacteria change their aqueous environments enough to cause precipitation of certain chemicals (calcium carbonate, iron oxide, silica, etc) which fossilze the creatures they surround
Term
Paleosols
Definition
Ancient soil profiles

- Often identified by reddish soils (oxidized iron and developed in places that have not been glaciated)

- environments: terrestrial
Term
Flute casts
Definition
Scoop-shaped structures on the bases of beds (caused by currents)

- environments: continental slope-rise (underse landslides - turbidites), continental shelf (storms - tempestites), slumps on slope, triggered by earthquakes.
Term
Stromatolites
Definition
* geopetal stucture

Horizontal to domal structures built by blue-green (cyano)bacteria

- environments: aqueous, usually form in carbonate environments

threat like bacteria grow upward thru sediment and caronate, mud and sand are trapped.
Term
What are the major depositional environments represented in the sedimentary record?
Definition
1. Marine
2. Mon-Marine
3. Transitional
Term
Non-Marine Envrionments Principle Characteristics
Definition
Terrestrial or freshwater fossils, sometimes reddish color
Term
Stream Channel Characteristics
Definition
asymetrical ripples, cross-beds, conglomerates
Term
Flood Plain Characteristics
Definition
Graded beds; symetrical ripples; paleosols
Term
Swamp Characteristics
Definition
coal; plant fossils; concretions
Term
Lake Deposits Characteristics
Definition
Clay; silt; varves; freshater fossils; dropstones in glacial lake deposits

Varves: represent clay (winter) silt (summer) from one year

Dropstones: result of stones frozen into glacial lake
Term
Alluvial Fan - Playa Lake Characteristics
Definition
Graded-beds;cross-beds;paleosols; evaporite minerals

- thin in valley, thixk against the mountain

- playa lakes oftentimes get destroyed and are not preserved b/c they are near tectonic environments
Term
Eolian Environments
Definition
Cross-beds; sand-sized grains; generally no fossils; commonly dunes

- wind dominated environments
- angle of repose in dune environments up to 45 degrees
- angle in aqueous environments up to 20
Term
Glacial Landscapes Characteristics
Definition
Till; cross-beds in outwash plains; glaicial grooves
Term
Transitional Marine - Non-Marine Environments Characteristics
Definition
Usually marine or brackish water fossils; sometimes reddish or greenish in color
Term
Beach characteristics
Definition
Sand-sized grains; crossbeds; shells
Term
Estuary Characteristics
Definition
Horizontal beds; crossbeds; oysters
Term
Tidal Flat
Definition
Are between high/low tide; symetrical ripple marks; mudcracks; rain impressions; few trace fossils
Term
Lagoon Characteristics
Definition
Symetrical ripple marks; horizontal bedding; occasional shelly beds; few body and trace fossils
Term
Delta
Definition
Cross-bedding; graded beds; fine to coarse grains
Term
Marine Environments Characteristics
Definition
Slope
Rise
Deep Ocean
Carbonate Platforms
Turbidite Currents
Marine fossils
Term
Theory of plate tectonics
Definition
Continents move over the Earth's surface becaue they form parts of moving plates
Term
Continental Drift
Definition
Concept that landmasses were united in a supercontinent; Pangea in the late Paleozoic
Term
Evidence for Pangea (4)
Definition
1. Jigsaw puzzle fit of continents
2. Glaciation in S. Hem
3. Similarities in S. Hem biotas
4. Similarities in positions of stratigraphic successions, Moutnain belts, etc.
Term
Glaciation in S. Hem as evidence for Pangea:
Definition
- large boulders (drift)
- till
- glacial grooves (most important b/c they show the direction of glcial flow)
- lake beds with dropstones
Term
Similarities in S. Hem as evidence for Pangea:
Definition
- Glosspoteris Flora (late Paleozoic)
- Lystrosaurus, Thrinaxodon, Gynognathus (Permian-Triassic reptiles)
- Mesosaurs (freshwater reptile, Permian)
found only in S. America and W. Africa
Term
How were biotic similarties in the Southern Hemisphere explained before continental drift?
Definition
1. Rafting
2. Land bridges
3. Island stepping-stones
Term
Evidence for fragmentation of Pangea (4):
Definition
1. rift valleys (east africa) = newly formed or failed rifts
2. mid-atlantic ridge (undersea mountain chain) marked place of rupture of the Southern Hemisphere landmass (Gondwana)
3. Ancient failed rifts = places of modern river valleys
4. paths of apparent polar wander
Term
Paths of apparent polar wander:
Definition
- young rocks: pole positions similar to present
- old rocks: pole positions progessively distant from present

if the north pole were stationary, continents would have wandered
Term
Seafloor spreading
Definition
Concept that the Earth's surface is composed of a moasic of mobile plates

- mobile lithosphere (crust and upper mantle) is driven by convection in asthenosphere (plastic region of mantle where rock becomes viscous and capable of flow under high temp/pressure condtions)

- when two adjacent convetion cells are positioned under a continent magma rises and rifting occurs - a midocean ridge is formed
Term
What happens during seafloor spreading?
Definition
-Lithosphere is subducted (destroyed) along deep-sea trenches

- Oceanic lithosphere is renewed every 300-400 m.a (usually only oceanic lithosphere is subducted b/c it is more dense so stratigraphic record comes mostly from continents)
Term
Active Plate Margin
Definition
Tectonically active zones between plates
Term
Convergent Margin
Definition
When plates collide

1. Subduction zones: continental plate slamming against oceanic plate. the oceanic plate gets subducted, volcanoes occur.

2. Suture zones: two continents collide; neither is subducted but folding is caused, mt ranges.
Term
Divergent Margins
Definition
Where plates spread apart

- rift zones, midocean ridges
Term
Passive Plate Margin
Definition
- Inactive plate margins
- Don't normally get destroyed versus active margins so there's a lot of stratigraphic evidence
- where most sedimentation occurs
Term
Transform fault boundary
Definition
Strike-slip faults form as plates diverge from mid-ocean ridges

- lithosphere is neither created nor destroyed

- displacement along faults can be 10-100s of kms; accreting tectonostratigraphic terranes.
Term
Tectonostratigraphic Terranes
Definition
Ocean basin added to continental crust
Term
Longest Interval of Geologic Time
Definition
-Precambrian
- Archean and proterozoic eons (begins at time of Earth's insepction ~4.5 g.a ago)
-88% of Earth's history
Term
Precambrian was time of:
Definition
-Formation of Earth, including solidification of lithosphere
-Development of the cratons (cores of continents)
-Formation of ocean and atmosphere
-1st life
-1st glacial episodes arising from 2 supercontinent assemblies
Term
Correlation of Precambrian strata
Definition
- Few fossils makes correlation difficult
- Most PC rocks metamorphic or igneous so dating is usually isotopic and there is a possibility of reset ages
- Oldest rock: ~ 4.1 G.A
Term
Differentiation
Definition
Heavy elements to center, lighter ones to lithosphere
Term
How did oceanic and continental lithosphere differentiate?
Definition
Fractional crystalliztion and partial melting
Term
Origin of Continents and Oceans
Definition
-Continental Accretion
-Mobile Crust Stage
-Platform stage
Term
Continental Accretion
Definition
Result of collision and orogenesis (mountain building)
Term
Mobile Crust Stage
Definition
(Archean) the "playdough" blobs were still warm so they could move and suture easily
Term
Platform stage
Definition
(Proterozoic)
- Lithosphere well-differentiated
- Plate tectonic processes operating
- stable continents provided a place for weathering, erosion, and deposition
- development of a reasonable stratigraphic record
Term
Proterozoic Supercontinents
Definition
Rodinia and Pannotia
Term
Supercontinent breakup at end of proterozoic led to paleozoic continents:
Definition
1. Gondwana (S. Hemp continents: Africa, S. Am, Antarctica, Indian, and Australia)

2. Laurentia (Core of N. Am, Greenland, N. Ireland, Scotland, W. Norway)

3. Baltica (Sweden, S. Norway, Finland, Denmark)

4. Siberia (Russia east of Urals)
Term
Early atmosphere and ocean produced by:
Definition
Outgassing

- 4.5-3.0 Ga: mostly Nitrogen, with lesser amounts of water vapor, CO2, SO2, etc.

ANOXIC
Term
Banded Iron Formation
Definition
Alternating thin beds of ferric iron and SiO2 (chert) 3.7-1.9 Ga

ANOXIC
Term
Red Beds
Definition
FeO in sediments [1.9 Ga - phanerozoic]

Oxic
Term
Origin of oxygen in atmosphere:
Definition
-Mostly due to photosynthesis of cyanobacteria

- chemical dissociation of carbon dioxide (by UV radiation)

- an anoxic early atmosphere was critical to the evolution of life
Term
What we cant' recreate in a lab?
Definition
-formation of cell wall
-reproduction
-spark of life
Term
Precambrian life: major steps (7)
Definition
1. chemosynthesis
2. photosynthesis
3. heterotrophy
4. symbiosis & development of eukaryotic cell
5. sexual reproduction and genetic recombination
6. multicelluarl organisms and organ systems
7. resistant skeletons
Term
Chemosynthesis
Definition
- Archaeobacteria (3.5 Ba)
- Making their own food
- Prokaryotes capable of living under anoxic conditions
Term
Photosynthesis
Definition
-Eubacteria 3.5 Ga
-development of oxygentated atmosphere
Term
Hetertrophy
Definition
Predation
Term
Symbiosis & Development of Eukaryotic Cell
Definition
As result of incomplete heterotrophy. Blob eats prokaryote.
Term
Pluses of multicelluar organisms and organ systems:
Definition
- changes can develop faster than they could before with asexual creatures

- division of functions among organ systems leads to efficiency
Term
Pluses of resistant skeletons:
Definition
- protect against UV rays, predations
- anchor muscle systemts
Term
Phanerozoic Life: Major Steps (3):
Definition
1. invasion of land (ordovician 470 Ma) spores of what appears to be land-dwelling plants, arthropods first animals

2. invasion of air (devonian 360 Ma) insects primitively have wings

3. development of social structures (carboniferous 320 Ma) us, insects, dinosaurs
Term
Cambrian Life Forms
Definition
Shelly fossils: trilobites (most common), brachiopds, archaocyathids, mollusks, hyoliths, 1st chordates
Term
Early Paleozoic Marine Revolution
Definition
- Sweeping reorganization of marine ecosystems
- adaptive radiation of multicellular animals ("cambrian explosion")
- changes in predator-prey systems led to predation resistand skeletons
- mat-dominated communities gave way to burrowed sedimentse
-organismic control over geochemical cycles
Term
Burgess Shale Type Deposits
Definition
Deposits of exceptionally preserved organisms

- the preservation of non-biomineralized parts
Term
Factors in burgess-shale type deposits
Definition
- Biological innovations
- favorable depositional conditions:

* rise in sea level onto continental shelves and rapid sedimentation on shelves
* burial of organic remains in environments limiting predation (anoxic; salinity stressed envrionments)
Term
Cambrian Mass Extinctions
Definition
Series of extinctions resulting in overturn of biota.

At a rate of every 1-2 millions years.
Term
Ordovician Period
Definition
- Tremendous radiation of marine invertebrates: triolovites, bryozoane, brachiopods, corals, mollusks, echinoderms,etc.

-1st land plant spores

- mass extinction at end. why? we don't know.
Term
Middle Paleozoic Life
Definition
- Mid-paleozoic marine revolution
- diversification of land plants (Silurian-Devonian)
- 1st land animals(Silurian arthropods)
- 1st insects(devonian, scales on backs modified to wings)
- 1st gymnosperms and forests (devonian)
- 1st land vertebrates (devonian)
- mass extinction (devonian)
Term
Angiosperms
Definition
flowering plants
Term
1st land vertebrates
Definition
(Devonian)

Amphibians; evolved from lobe-finned fishes - could breathe air but still spent most of time in water.
Term
Gymnosperms
Definition
non-flowering plants
Term
Mid-Paleozoic Marine Revolution
Definition
-escalation in predator-prey systems, especially fishes molluks, brachiopods, enchinoderms.

- fish with jaws imposed lots of pressure on other predators and prey
Term
Late Paleozoic Life
Definition
-Adaptive radiation of crinoids (carboniferous)
-1st reptiles (carboniferous)
-Adaptive radiation of insects, gymnosperms - extensive coal swamps
-Pangea
-Mass extinction @ end of permian
-transition to land
Term
Mass extinction at end of Permian
Definition
- Most significant in Earth history

- more than 95% of marine invertebrates gone; brachiopods, snails, etc.

-Supercontinent assembling, squishes most of the ocean shelves where these creatures live, changes climate and ocean circulation patterns
Term
Transition to land problems (5):
Definition
1. gas exchange
2. osmotic balance
3. support (w/o H2O buoyancy)
4. desication (and temp regulation)
5. protection of babies (developing embryos)
Term
Gas exchange solutions:
Definition
Animals: lungs, trachea

Plants: stomata
Term
Osmotic Balance Solutions:
Definition
Animals: internal saline system (blood)

Plant: Vascular network (roots)
Term
Support solutions:
Definition
Animals: skeletal, muscular, and ligaments framework

Plants: vascular tissue (w/ water), lignin (cellulose)
Term
Desication and temp regulation solutions:
Definition
Animals: skin, cuticle, scales, hair, feathers

Plants: waxy, epicuticle, bark
Term
Protection of babies solutions:
Definition
Animals: amniotic egg, internal fertilization and embryonic development

Plants: seed covers, cones, seeds enclosed in ovaries
Term
Phylogenetics
Definition
-Cladistics
-Core concepts: derived characters are used to reconstruct common ancestry relationships.
Term
Apomorphies
Definition
evolutionary novelties
Term
Synapomorphies
Definition
shared, derived characters
Term
Ingroup
Definition
Taxa of interest
Term
Outgroup
Definition
Related group showing primitive character states
Term
Sister group
Definition
closest related outgroup
Term
Plesiomorphy
Definition
primitive character state
Term
Autopomorphy
Definition
derived character present in only one taxon
Term
Homoplasy
Definition
Character state that arose independently in different taca (convergent character)

wings in birds and bees
Term
Taxa
Definition
Species: a lineage; the largest unit of taxic evolution.

Clade: (monophletic group) a group of species that includes an ancestral species and ALL OF ITS DESECENDANTS
Term
Artificial Taxa (3):
Definition
1. Paraphyletic groups: one or more descendents of an ancestor are excluded from the grou (reptiles; mammals and birds are excluded)

2. Polyphletic groups: the common ancestor is placed in another taxon (sponges; derived from 2+ ancestors)

3. Grade: artificial taxon; represents a level of evolutionary organization (the flyers; everything that can fly)
Term
Cyclothems
Definition
-Cyclic sedimentary successions - basis for Walther's Law

- Often marine/non-marine cycles w/ coal beds
Term
Development of Appalachian Mountains
Definition
- Valleys are anticlines and hills synclines

(Ordovician) Taxonic orogeny = collision of Laurentia w/ Avalonia Islands

(Devonian) Acadian orogeny = Laurentia and Baltica collide

(Pennsylvannian) Appalachian orogeny = Laurentia and Gondwana collide - creation of Pangea
Term
Exotic Terranes
Definition
Pieces of exotic lithosphere sutured to another continent
Term
Early-Mid Mesozoic Paleogeography and Sealevel
Definition
-Beginning of Triassic: Pangea was assembled. Sea level relatively low.

-Initial breakup of Pangea (Triassic-Jurassic) resulted in rising sea level.
Term
Late Mesozoic Paleogeography and Sea Level
Definition
- Cretaceous: high spreading rates at mid-ocean ridges.

- sea level rose dramatically (almost highest level in history) creating vast eperic seas led to creation of western coal deposits (Carboniferous, ordovician, cambrian).
Term
Mesozoic Terrestrial Life
Definition
- Gymnosperms predominate (Triassic-Jurassic);
- Angiosperms evolve (Jurassic-Cretaceous);
- Insects radiate (help pollenate angiosperms);
- 1st mammals (Triassic);
- Age of "reptiles" - diversify and dominate land and sea.
Term
Mesozoic Marine Revolution
Definition
- escalation in predator-prey systems, especially in fishes, mollusks, vagile echinoderms (hardened shells, spines, poisons.)

- scleractinian corals evolve (reefs);
- rudist clams (reef builders);
- crustaceans and enchinoderms (more spiny, thicker skeletons;

- 1st bony fishes (Teleosts, Triassic).
Term
Reptiles
Definition
Dinosaurs, crocodiles, pterosaurs, turtles, lizards, shankes, icthyosaurs, plesiosaurs, mosasaurs, etc.
Term
How are the major groups of dinosaurs identified?`
Definition
- Pelvic morphology:

- Ornithischia: bird hipped, bones facing backwards;

- Saurischia: lizard hipped, bones facing in opposite directions.
Term
Theropoda
Definition
Meat-eating Saurischia
Term
Sauropoda
Definition
Long-necked plant eaters
Term
Anklyosaur
Definition
Giant turtle looking, armored, clubs on end of tails
Term
Stoyosaur
Definition
Plated backs
Term
Ceratopsia
Definition
horned dinosaurs
Term
Pachaphalosaur
Definition
bone heads
Term
Ornithopoda
Definition
Duckbilled
Term
Birds are dinosaurs because...
Definition
They are feathered saurischian theropods.

- bird style hips arose twice - homoplasy.
Term
K/T Extinction
Definition
Mass extinction at end of cretaceous:

-dinos, pterosaurs, icthyosaurs, plesiosaurs, ammonites, rudist clams, many marine planktonic algae, etc. went extinct.

- Cause: ? Time of rapid rifting, sea level rise, volcanic activity, rapid climate change, meteorite or asteroid impact.
Term
Cenozoic Paleogeography and Sea Level
Definition
- Continents drfit toward current positions;

- Sea level highly variable, related in part to glacial - interglacial episodes.
Term
Cenozoic Tectonic Events
Definition
- Basin and Range formed (Oligocene);
- Columbia and Snake River plateau formed (Miocene);
- uplift of Colorado Plateau (Pliocene).
Term
Cenozoic Life
Definition
- Mammals diversify (Age of Mammals);
- Adaptive radiation of angiosperms - appear in Jurassic, dominant in Cretaceous, evolved by leaps and bounds thru Cenozoic.

- grasses radiate (Miocene)
- Insects radiate (coeveloution with angiosperms and mammals)
Term
End - Pleistocene Extinction
Definition
- Pleistocene glacial episodes: much of Northern Hemisphere covered by continental glaciers;

- Mass extinction wiped out (affecting mostly terrestrial mammals) giant sloths, mammonths, mastadons, cave bears.
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