My Notes: Metamorphic Rocks, Geology of Saskatchewan, and Meteorites Flashcards
What are the 3 things that result from groundwater?
- concretions and nodules
- veins
- cement, fossil replacement
What are plastics made from?
petroleum
What rocks are the most economically useful?
sedimentary
What are the two types of metamorphism?
Contact and Regional
What does the type of metamorphism depend on?
the temp that was reached
When does the metamorphic process begin?
at ~250 degrees celsius
Which melts at a lower temp, granite or basalt?
granite
How does a mineral with an atomic lattice structure break down?
Slowly as atoms are freed from the crystal lattice by increased vibration. Breaks electron bonding with adjacent atoms and combines with other atoms.
What is the temp of medium grade meta. rx?
450-550
What is the temp of low grade meta. rx?
250
What the temp of high grade meta rocks?
650
What is the temp that all rocks, regardless, will melt at?
1200
What does recrystallization result from
“solid state ion diffusion” which increases with temperature (pressure a bit)
What is the melt temp at contact metamorphism usually?
700
What is contact metamorphism?
- Batholith exposed by erosion
- Beside that body, there is a zone where country rock is metamorphosed. Fades away as it moves away from the batholith’s heat.
What are 3 forms of evidence of asteroid and meteoroidal impacts?
- impact craters
- meteorites
- tektites
What happens with big meteorites?
They disintegrate through atmosphere, hit ground with explosive force pound for pound, and explode when they hit and vaporize.
- Leave no record except microscopic vapour
- Leave impact crater
Why is the Earth not covered in impact craters like the moon is?
Earth is not full of impact craters because of geological processes that wipe them out –> subduction, burial, erosion, filled with stone, etc.
How many impact craters are left in Saskatchewan? How many are buried, of those how many are left?
- 6
- 3
- 2
What was buzzard coulee?
Fireball —> exploded –> left pieces that exposed –> 6 explosions total
How high was buzzard coulee? How long was it is the atmosphere and how fast did it go?
- 80 km high
- 20 km/sec
- 5 seconds in atmosphere
What are pits in meteorites due to? What are they good for?
Irregular melting and help identify meteorites
What is the difference between meteorites and meteors/meteoroid?
- Meteorites are not hot or radioactive when they land. They make it to ground.
- Meteors are in air or in space
What is on the inside of the majority of iron meteorites?
a crystal structure
What do chrondites contain? Percent of fall
- contain chrondules
- 86% of falls
What don’t achrondites contain? Percent of falls?
- don’t contain chrondules
- 8% of observed falls
What are CAI’s?
- Pre-solar
- Older than the age of Earth
Do most achrondites have metallic iron?
Most have no metallic iron
Do achrondites contain CAI’s?
no
What are mesosiderites?
fragments of iron and stone
What are impact breccia?
A collection of broken fragments (rubble pit) of several different meteorite types…mesosiderites. MIB’s are common in all the chemical types of meteorites, but not always easy to recognize. (Rarest kind of meteorite)
What are primitive meteorites?
We call chrondite meteorites the primitive meteorites because they recognize the study that all the solar system was made of. Oldest stuff we have.
What are carbonaceous chrondites?
- Have carbon in an organic form –> amino acids
- Amino acids are the basic chemical material of DNA
- Our biological material not found in chrondites
What are the primary geological resources of Saskatchewan?
petroleum and potash
