Studied by 2 peoplePangea
Name of supercontinent proposed by Alfred Wegner meaning all land, existed about 200 million years ago.
Mesosaurus
One of Wegner's proof of fossil evidence for continental drift. Wegner believed that South america and Africa must have joined when the dinosaur lived.
5-15 centimeters a year
How fast do plates of the lithosphere move?
Lithosphere
From which layers of Earth are plates composed?
divergent boundary
Found where two of Earth's plates move apart. Oceanic lithosphere is created. Most are spreading centers located along crests of mid ocean ridges, some may occur on the continents.
Convergent boundary
Form where two plates move together. Lithosphere can be destroyed. Plates collide and interact, producing features like trenches, volcanoes, and mountain ranges.
Transform boundary
Plates may grind past each other without destroying the lithosphere
oceanic-continental convergent boundary
When oceanic lithosphere is subducted beneath a continental plate, it creates a continental volcanic arc.
Oceanic-oceanic convergent boundary
When one oceanic plate is subducted beneath another oceanic plate, it forms a volcanic island arc.
Continental-continental convergent boundary
When continental lithosphere cannot be fully subducted, because it isn't very dense. The collision of two continents forms mountain ranges.
along mid-ocean ridges
Where are the majority of transform faults on earth?
Reveals that the poles switch positions, proves paleomagnetism
What does a magnetic reversal reveal?
Mantle convection from earths internal heat
What is the ultimate cause of plate movement?
Principle of Uniformitarianism
The idea that physical, chemical, and biological laws that operate today also operated in the past.
Cross cutting relationships
States that a fault or intrusion must be younger than any geologic formation through which it cuts.
Relative dating
Identifies the chronological order in which rocks formed, but not the exact age. Can tell us the sequence in which events occurred, but not how long ago.
Sedimentary rocks
In what type of rock are fossils found?
If something posses hard parts it has a better chance of becoming a fossil
What is the significance of hard parts in fossil formation?
Fossil succession
States that fossil organisms tend to be found in the same general order at different locations.
They are used for relative dating, and to define geological periods
What's the importance of index fossils?
Developed by Charles Darwin, explains why we evolve and how it helps us survive
What is the significance of the theory of evolution?
After one half life, half parent material half daughter project, etc.
How do you read and interpret a radiometric decay curve?
When an organism dies the amount of carbon-14 gradually decreases as the carbon-14 decays, by comparing the ratio of carbon-14 to carbon-12 in a sample, radiocarbon dates can be determined.
What is the significance of carbon-14 in radiometric dating?
4.54 billion years old
What is the approximate age of Earth?
Eons
The four long units that Earth's history is divided into.
Eras
There are three within the Phanerozoic eon, the Paleozoic, Mesozoic, and Cenozoic.
Periods
What each era is divided into, different geologic events, environmental conditions and life forms characterize them.
Epochs
What periods are divided into.
3.5 billion
What is the age of the oldest fossils on Earth?
Precambrian, Paleozoic, Mesozoic, Cenozoic
What is the relative order of the eras of Earths history?
The sea from cyanobacteria
Where did life originate according to modern scientific theory?
By coal deposits, when coal formed
How was the carboniferous named?
The precambrian (88% of earths history)
What is the longest division of geologic time?
Summer solstice
First day of summer, June 20 or 21, axis is leaning 23.5 degrees north, tropic of cancer.
Winter solstice
First day of winter, December 21 or 22, axis is leaning 23.5 degrees south, tropic of Capricorn.
Spring equinox
Occurs on March 19th or 20th, marks start of spring, 0 degrees latitude, sun's rays strike the equator, day is equal to night.
Autumnal equinox
Start of autumn, September 22 or 23, 0 degrees latitude, sun's rays strike equator, day is equal to night.
Conduction
The transfer of heat through matter by molecular activity.
Convection
The transfer of heat by mass movement or circulation within a substance.
Radiation
Mechanism of heat transfer where energy travels out in all direction from its source, does not need a conductor.
The higher up you are the colder it will be
How do altitudes affect climate?
Land heats and cools more rapidly than water
Differences in heating of land and water?
Leeward coast
Location where prevailing winds blow from the land to the ocean (get their winds from land). more extreme temperatures and hotter and drier.
Windward coast
a coastal location where prevailing winds blow from the ocean onto the shore (get their winds from water)
High albedo
Clouds that reflect a significant portion of the sunlight that strikes them back to space
Low albedo
When clouds absorb radiation from the land
Rain, sleet, snow, hail, freezing rain
What are the various forms of precipitation?
Rain
drops of water that fall from a cloud and have a diameter of at least .5 millimeters
Snow
precipitation falling from clouds in the form of ice crystals
sleet
the fall of small particles of clear to translucent ice
Glaze
Also known as freezing rain, results when raindrops become supercooled, they fall through subfreezing air near the ground and turn to ice when they impact objects
Hail
Produced in cumulonimbus clouds, hailstones begin as small ice pellets that grow by collecting supercooled water droplets as they fall through clouds, if the pellets encounter a strong updraft they will either be carried back or fall to the ground.
Evaporation
Liquid to a gas, heat is absorbed
Condensation
Gas to a liquid, heat is released
Sublimation
Solid to a gas, heat is absorbed
Deposition
Gas to a solid, heat is released
Melting
Solid to a liquid, heat is absorbed
Freezing
Liquid to a solid, heat is released
Stratus clouds
means a layer, clouds are sheets or layers that cover much or all of the sky.
nimbus clouds
Rainy cloud
cirrus clouds
means a curl of hair, clouds are white, thin, and found high in the atmosphere.
Cumulus clouds
means a pile, consist of rounded individual cloud masses
The pressure gradient force (differences in air pressure)
What force generates winds?
High pressure system
Anticyclones are centers of high pressure, air spirals outwards in a clockwise pattern in the northern hemisphere (counterclockwise in the southern hemisphere).
Low pressure system
Found in cyclones, air spirals in toward the center in a counter-clockwise pattern in the northern hemisphere (clockwise in the southern hemisphere).
Cyclones
Centers of low pressure, the pressure decreases from the outer isobars toward the center.
Anticyclones
Centers of high pressures, the values of isobars increase from the outside toward the center.
After the direction from which they come
How are winds named?
El Nino
At irregular intervals of 3-7 years, these warm countercurrents become unusually strong and replace normally cold offshore waters with warm equatorial waters. Episodes of ocean warming that affect the eastern tropical Pacific.
La Nina
When surface temperatures in the eastern Pacific are colder than average.
classified by overall temperature and from the surface over which they form
Air masses that affect the US?
A cold front has blue triangles, and a warm front as red semi circles
How to identify cold and warm fronts on a weather map?
Cold front
It forms when cold dense air moves into a region occupied by warmer air. thunderstorms and heavy rain.
Warm fronts
It forms when warm air moves into an area formerly occupied by cooler air. Warmer temperatures, light to moderate extended rain.
Cumulus stage
first stage of thunderstorm, air rises supplying warm, moist air to the cloud
Mature stage
second stage of a thunderstorm, heavy precipitation
Dissipating stage
last stage of a thunderstorm the cloud begins to evaporate
April-June
In which season are tornadoes the most prevalent?
It sinks, subsides
What happens to air in a cyclone?
Continental Polar (cP)
What air mass affects northern Canada?
subduction zone
the region where an oceanic plate sinks down into the asthenosphere at a convergent boundary, usually between continental and oceanic plates
Continental-continental convergence boundary
What kind of boundary created the Himalayas?
maritime
air mass is over the ocean
continental
over continents
tropical
named this if air mass is located in the southern hemisphere
polar
named this if air mass is located in the northern hemisphere
cyclone in the Northern Hemisphere
air flows inward and blows out counterclockwise
cyclone in the Southern Hemisphere
air flows inward and blows out clockwise
Air subsides in a
cyclone
How old is the material if it’s half life is 100 million years and it has 1/32 parent remaining?
500 million
Which air mass is responsible for nor’Easters?
Maritime polar
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