Term
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Definition
| The study of sedimentary and volcanic layers through time |
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Term
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Definition
| studying the rocks/what the rocks are made of in the layers |
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Definition
| studying the fossils within the layers of stratigraphy |
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Definition
| formation, group/comparitive, member, beds |
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Term
| formation (main) division of stratigraphy |
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Definition
| used to identify sequences of deposition |
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Term
| group/comparative division of stratigraphy |
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Definition
| used to compare depositional events |
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Term
| member division of stratigraphy |
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Definition
| used to identify individual depositional events |
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Term
| bed division of stratigraphy |
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Definition
| used to identify individual layers in a member |
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Definition
| comparing one rock to another to determine estimated age |
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Term
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Definition
| assigning a # to a rock when determining age |
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Term
| principles of stratigraphy |
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Definition
| original horizontality, superposition, lateral continuity, inclusions, and cross cutting relations. |
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Term
| principles of original horizontinality |
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Definition
| as sediments are deposited, they are laid out in horizontal sheets |
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Term
| principles of superposition |
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Definition
| when looking at a sequence, oldest rocks are at the bottom with the youngest at the top |
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Term
| principles of lateral continuity |
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Definition
as sediments are being deposited they will spread out laterally until
1. taper (thin out)
2. lean/touch a barrier
3. gradually change into another rock |
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Term
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Definition
any feature (Fragments, fossils) included in a rock must be older than the rock
- also generated when magma intrudes upon a rock and breaks off |
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Term
| principles of cross cutting |
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Definition
| any feature (faults/igneous intrusions) that cut across stratigraphy must be younger than the stratigraphy it cuts |
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Term
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Definition
| missing geologic time, erosional surfaces, sometimes lock or deposition. |
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Term
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Definition
| disconformity, nonconformity, angular conformity |
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Term
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Definition
| missing time between parallel surfaces |
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Term
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Definition
| missing time between stratigraphy and an igneous or metamorphic body |
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Term
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Definition
| missing time between non-parallel layers |
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Term
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Definition
| age determination based on characteristics such as faunal succession and continuity |
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Term
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Definition
| utilizes the atomic decay of elements |
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Term
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Definition
| number of protons in a nucleus |
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Term
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Definition
| number of protons and neutrons |
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Term
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Definition
when ann element holds the same number of protons but varies in number of neutrons
EX: Carbon = 6 protons
Carbon Isotope (carbon 14) = 6 protons 8 neutrons. |
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Term
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Definition
| original radioactive element (will decay) |
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Term
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Definition
product of radioactive decay of parent isotope
- can be stable unstable (unstable = radioactive) |
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Term
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Definition
| time required for half of the parent to decay to the daughter (can only date up to 5 half lives) |
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Term
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Definition
| the nucleus ejects 2 protons and 2 neutrons |
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Term
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Definition
| proton captures an electron, turning into a neutron |
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Term
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Definition
| neutron ejects an electron, turning into a proton |
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Term
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Definition
| change in form due to being exposed to conditions unlike those in which it formed |
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Term
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Definition
| heat, pressure, and fluids |
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Term
| agents of metamorphism: heat |
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Definition
temperature increases with depth (~20º-30º/km). The heating is slow, but the reaction to the heat is fast
- can range as low as 200ºc up to 700º-1200ºC |
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Term
| agents of metamorphism: pressure |
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Definition
| 1000 atmosphers = 1000 bars = 1kbar = 3km in depth |
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Term
| agents of metamorphism: fluids |
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Definition
| H2O and CO2 act as catalysts and aid in the recystallization of minerals |
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Term
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Definition
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Term
| low grade metamorphic rock |
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Definition
| low temperature, low pressure |
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Term
| intermediate grade metamorphic rocks |
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Definition
| mid temperature, mid pressure |
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Term
| high grade metamorphic rocks |
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Definition
| high temperature, high pressure |
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Term
| regional metamorphism characteristics |
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Definition
-pressure driven (high temp/high pressure)
-convergent boundaries (subduction and continental collision |
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Term
| cataclastic metamorphism characteristics |
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Definition
-occur on the fault
-very rapid
- high temp/high pressure |
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Term
| contact metamorphism characteristics |
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Definition
-contact with magma or lava
-relatively small areas
-high temp / low to moderate pressure
-heat driven |
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Term
| hydrothermal metamorphism characteristics |
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Definition
-aka seafloor metamorphism
-divergent boundaries
-hot iron rich fluids |
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Term
| burial metamorphism characteristics |
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Definition
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Term
| impact metamorphisms characteristics |
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Definition
-instantaneous in heat/pressure
-widest range in temp/area/pressure |
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Term
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Definition
| parallel alignment of minerals due to directed pressure |
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Term
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Definition
| slaty (shale, slate, phyllite) |
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Definition
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