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92 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Age of the Earth |
4.56 Billion Years |
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Age of Earth Rocks |
Oldest are 3.96 Billion years in NW territories of Canada |
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Age of Meteorites |
4.56 Billion years old |
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Age of moon rocks |
4.45 billion years old |
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Fossil |
Any remnant or indication of prehistoric life preserved in rock |
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Paleontology |
Study of fossils |
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Rock types- intrustive Igneous |
No. Volcanic tuff the exception |
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Rock types- metamorphic |
Rarely |
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Rock types- Sedimentary |
Yes |
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Oldest fossils |
Algal fossils found in Australia 3.5 billion years ago |
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Fossil preservation- original remains |
Insects trapped in amber Wolly mammoths in permafrost Shark teeth |
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Fossil preservation- replaced remains |
Hard parts of buried organisms are replaced by minerals |
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Fossil preservation- replaced remains Carbonization |
Plant remains are decomposed by bacteria under anaerobic conditions Hydrogen, oxygen, nitrogen are driven off, leaving behind only carbon |
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Fossil preservation- molds and cast of remains |
Just like your favorite jello mold |
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Fossil preservation- trace fossils |
Shows activity of an animal Coprolite-poop |
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Index fossils- four conditions |
Rapid evolution Easy preservation Widespread geographic distribution Easy identification |
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Over __ of all species are now extinct |
99% |
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Extinctions occur at what rate |
Uneven |
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Extinctions can __ evolution |
Accelerate |
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Organisms that dont go extinct may fall into |
Long term decline after "event" |
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Mass extinctions are thought to result when |
A long term stress is compounded by a short term shock |
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Ordovician-Silurian extinction event |
440-450 million years ago Second largest extinction 27% of all families and 57% or all genera went extinct 2 burst seperated by a million years Continental drift of a siginifigant landmass into the south polar region,causing a global temperature drop, glaciation, and consequent lowering of the sea level, which destroyed species habitats around the continental shelves. |
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Late devonian extinction event |
•360-375 million years ago •Extinction was over 20 million years •Time estimates ranging from 500,000 to 15 million years. •Mostly impacted marine life -Seafloor organisms were decimated •70% of all species •Reason is unclear -Change in sea level -Meteor impact -Volcanic eruptions |
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Permian-Triassic-Great Dying extinction event |
251 million years ago •1-3 pulses • due to gradual environmental change, while the later was probably due to a catastrophic event •largest extinction •96% of all marine species and 70% of terrestrial vertebrae •large evolutinary signifigance •coal gap •4m to 6m years after the extinction; and some writers estimate that the recovery was not complete until 30 m years |
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Triassic-Jurassic Extinction event |
205 million years ago At least half of the species now known to have been living on Earth at that time went extinct. Event happened in less than 10000 years. 23% of all families and 48% of all genera went extinct Explanations: Climate change Asteroid impact Volcanic eruptions |
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Cretaceous-tertiary extinction event |
65 million years ago 17%of all families and 50% of all genera went extinct Ended reign of dinosaurs Opened the way for mammals Very unevennin the loss of species Some species had heavy losses, while some were minimally impacted |
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How do we know? -extinction events |
Fossil record Issues with the Fossil Record Older fossils are buried deeper Dating fossils can be difficult Productive fossil beds are researched more, leading to unbalanced knowledge Hard for fossils to survive Marine fossils are preserved more frequently |
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Causes for extinctions |
Flood basilt events: 11 occurrences, also sheated with significant extinctions. But wignall(2001) concluded that only 5 of the major extinctions coinceded with flood basalt eruptions and that the main phase of extinctions started before the eruptions Sea level falls:12, of which 7 were associated with significant extinctions Asteroid impacts producing craters over 100km wide: 1, associated with 1 mass extinction. Asteroid impacts producing craters less than 100km wide: over 50, the great majority not associated with significant extinctions. |
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Flood basalts |
Particulates inhibit photosynthesis Sulfur oxides cause acid rain Global warming from carbon dioxide emissions CRB 63,000 sq. Miles Up to 6,000 feet deep |
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Sea level changes |
Disrupts global weather patterns Impacts continental shelves |
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Other reasons for extinctions |
Anoxic events Hydrogen Sulfide emission from the sea Supernova Contintental drift Plate tectonics |
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Current extinction event? |
Holocene epoch |
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There are ___ soil orders |
12 |
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Soils are mostly ____ |
Mineral particles -45% |
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What lies below the E horizon? |
B- subsoil |
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Oxisols are soils with large amounts of: |
Oxygen containing compounds |
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Granite exfoliation would best be described as a type of ______ |
Pressure release |
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Porosity is a materials capacity to transmit fluids true or false |
False |
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The median yield for a well in NH is _____ gpm |
6.5 |
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An anticline is a fold which forms an arch true or false |
True |
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Seismology is the study of |
Earthquakes |
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Animals can sometimes predict earthquakes true or false |
True |
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The Richter Scale measures intensity T o F |
False |
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The focus can be found on the surface of the earth ToF |
False |
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Most earthquakes occur near plate boundaries ToF |
True-95% |
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Water Cycle |
1.Evaporation 2. Precipitation 3. Infiltration |
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2 Types of Water Flow |
Channel Flow- When flow is confined to trough-like depressions Sheet Flow-Continuous film of water flowing over the surface |
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T o F: Velocity decreases as water becomes wider |
True |
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Rivers tend to from ___ shaped valleys |
V |
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Glaciers tend to form ___ shaped valleys |
U |
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T or F: Stream Discharge changes by urbanization |
True |
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_____ is the breakdown of sediments |
Weathering |
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____ TRANSPORTS the broken sediments |
Erosion |
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Dissolved load |
Part if a streams load consisting of ions in solution |
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Suspended load |
Smallest particles carried by running water, which are kept suspended by fluid |
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Bed load |
Larger Particles that are transported along the bed of the stream |
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River Deposition Alluvium |
All detrital sediments transported and deposited by running water |
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River Deposition Braided Stream |
Multiple dividing & rejoining channels |
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River Deposition Meandering Stream |
Single, sinuous channel with broadly looping curves |
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Drainage Basin or Watershed |
Total area that contributes water to a given stream |
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Drainage Patterns Dendritic |
Most common and looks like a tree branch |
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Drainage Patterns Rectangular |
-Tributaries join at right angles -Strongly controlled by geologic structures |
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Drainage Patterns Trellis |
Parallel main streams with tributaries |
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Drainage Patterns Radial |
Streams flow outwards in all directions |
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Drainage Patterns Deranged |
Irregular Good example is a swamp |
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Valley |
Low area on land bounded by higher land |
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Stream Piracy |
The breaching of a drainage divide and diversion of part of the drainage of another stream. |
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Superposed river |
When the river is older than the mountain itself, and the mountain forms around the river. |
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Cambrian Explosion |
When first fossils appeared |
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Relative Time |
Places event in sequential order without know-date. Will tell you which came 1st, 2nd, 3rd, etc. but not the date they occurred. |
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Absolute Time |
-Provides specific dates -Most common form is radiometric dating -Cannot always be used |
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Principles of Relative Dating |
-Original Horizontally* -Super position* -Lateral Continuity* -Cross-Cutting Relations -Inclusions -Fossil Succession -Unconformities *Steno's Principles |
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Principle of Original Horizontally |
Sediments are deposited in horizontal or nearly horizontal layers |
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Principle of Superposition |
In a vertical sequence of undeformed sedimentary rocks, the relative ages of the rocks can be determined by their sequence-oldest at the bottom, followed by successively younger layers |
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Principle of Lateral Continuity |
Rock layers extend outward in all directions until they terminate |
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Principle of Cross-Cutting Relationships |
An igneous intrusion or fault must be younger than the rock it intrudes or cuts |
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Principle of Inclusions |
Inclusions in a rock unit are older than the parent rock |
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Xenoliths |
A piece of rock within an igneous rock that is not derived from the original magma but has been introduced from elsewhere, esp. the surrounding country rock **Xenoliths= igneous only Inclusions= all rocks |
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Principle of Fossil Succession |
Fossils and assemblages of fossils succeed one another through time in a regular and predictable order. |
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Unconformities |
A break in the geologic record represented by an erosional surface separating younger strata from older rocks. |
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Hiatus |
The interval of geologic time not represented |
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Three main types of Unconformities |
1. Disconformity 2. Angular Unconformity 3. Non Conformity |
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Disconformity |
A surface of erosion, or nondeposition, separating younger strata from older strata, both of which are parallel with one another. |
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Angular Unconformity |
An erosional surface on tilted or folded strata over which younger strata were deposited |
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Non Conformity |
An unconformity in which stratified sedimentary rocks overlie an erosion surface cut into igneous or metamorphic rocks. |
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If just an intrusion, the intrusion is ____. |
Younger |
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If erosional (non conformity), then the sedimentary rocks are____. |
Younger |
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Radioactive Decay |
Dating Method The process where an unstable atomic nucleus releases energy |
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Half life |
The time it takes for half of the atoms of the original unstable parent element to decay to atoms of a new, more stable daughter element. |
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Radioactive Decay use in rock types Igneous |
Time elapsed since cooling |
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Radioactive Decay use in rock types Metamorphic |
Time elapsed since metamorphism |
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Radioactive Decay use in rock types Sedimentary |
Measures age of particle, not rock |
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