Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

G108 > Class Notes Unit 6 Part 2 > Flashcards

Class Notes Unit 6 Part 2 Flashcards

1
Q

What 4 things do convergent P.B result in the formation of?

A

1) earthquake zones
2) most of Earth’s volcanism that is visible
3) oceanic trenches
4) tectonic / orogenic Mountain belts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the difference between mountains at CPB and DPB?

A

CPB are not the same that form at divergent plate boundaries–they are not tectonic / orogenic at DPB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 3 possible types of CPB collisions?

A

1) oceanic crust –> cont. crust
2) o.c. –> o.c.
3) c.c. –> c.c.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two types of volcanic arcs?

A
  1. volcanic continental arcs (on land)

2) volcanic island arcs (sea)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 Earthquake benioff zones?

A

1-50 km…shallow
50-300 km…intermediate
300-670 km…deep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why is isostatic sinking important at CPB?

A

Because it makes more room for more stuff to be deposited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What forms tectonic mountains–mountain belts we call orogens?

A

10-30 km thick piles of sediments and volcanics and intrusions are compressed and deformed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How long does the orogen deformation phase last?

A

~ 100 my

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

___transformed into orogens.

A

Geosynclines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the evolutionary sequence of orogeny?

A

1) Erosion of pre-existing land mass and volcanism
2) deposition of sediment
- plate collision
5) uplift
6) orogeny
7) erosion of uplifted rocks
8) deposition
etc. …….

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the continent building process?

A

Sedimentary re-cycling plus additional volume through volcanic and intrusive rocks, partly derived from the mantle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Structural___causes mountains.___carves out individual structures.

A
  • structural

- erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When did most tectonic mountain building take place?

A

end of the Palaeozoic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the key to the origin of continents?

A

plate tectonics is the key

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 3 steps to the origin of the continents?

A

1) Continental breakup and continental growth
2) Continental accretion
3) Cratons and orogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the archean microcontinents?

A

S-R-H (Slave-Rae-Hearne Cratons)
N- Nain Craton
SC- Superior Craton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How old are the rocks of areas microcontinents?

A

older than 2.5 Ga

18
Q

When was the orogeny of the THO (Trans-Hudson Orogen)?

A

Began in 1.9 and finished in 1.8 Ga

19
Q

What did the S-R-H, N, and SC collide to form?

A

THO

20
Q

What are the rock ages of the THO?

A

2.9 (uncommon)-1.8 (1.9-1.85, mostly) Ga

21
Q

What is an example of a stitching orogen?

A

the THO because all three microcontinents of the Archean formed North America 1.8 billion years ago.

22
Q

What created North America?

A

The collision of S-H-R, N, and SC to form THO

23
Q

What is the name of the ocean between S-H-R and SC?

A

Manikewan Ocean

-seperates Archean continents

24
Q

What are the other proterozoic orogens?

A

WO - Wopmay Orogen 1.9-1.8 Ga
YO - Yavapai O. 1.8-1.7 Ga
MO - Mazatzal O. 1.7-1.6 Ga
GO - Grenville O. 1.2-1.0 Ga

25
Q

Briefly describe the building of WO, YO, MO, and GO.

A

After the 3 microcontinents collided, erosion dropped sediment off to the south side they formed orogenic belt (YO) followed by MO. This as a kind of accretion. Then, through erosion, deposition, geosynclines formed and Rodina came to be. Collision of these continents produced GO. Rodina then broke up.

26
Q

What happened 700 million years after the break up of Rodina and after erosion dumped stuff into the ocean?

A

Pangea assembled and formed Appalachian Orogen.

27
Q

When did Appalachian Orogen (AO) form?

A

450-250 Ma

28
Q

When did Cordilleran Orogen form?

A

150-50 Ma

29
Q

How did Cordilleran O. become tectonic mountain belt?

A

More accretion to North America. Erosion dumping sediment to western region of continent until cordilleran became tectonic mountain belt.

30
Q

The entire mantle is___.

A

convecting

31
Q

What causes divergence and subduction to occur?

Don’t even try to answer–just click it and read it several times

A

-Uplift of plume –> creates too slope
-Gravity takes over and if cracks and faults form gravity can pull them down the slope –> plate sliding
-As it is being arched up, cracks fill with magma which helps to widen cracks –> will push rocks away from divergent plat boundary –
Ridge push
- Lithosphere now unstable
-drag between lithosphere and stuff above
-Sheet may detach from continent
-As it cools –> dense and will sink (involves cool lithosphere and asthenosphere)
-Ends up going down and finish convective sell.

32
Q

What happens with convecting CPB and DPB? (how are they related, what causes mantle plumes, what are mantle plumes)?

A

CONVECTION CELL
-More than heat flowing, rock is flowing which forms the orogens called mantle plumes which causes Divergent Plate Boundary. When they go down again, they form Convergent Plate Boundary.

33
Q

What distance does a plume advance each year?

A

several cm/yr

34
Q

What does the processes involved inflate tectonics create?

A

Most of the important physical features that occur at the earths’ surface, and the affects humans.

35
Q

What happens as each plate moves?

A

The continents on it change their location, thus their climate and other environmental factors that affect organic life–and is a factor in organic evolution

36
Q

What is cratoniztion?

A

geosynclines –> orogens –> carton

37
Q

What is volume added to the continental crust from? What is this due to?

A

Volume added to continual crust (sial) through volcanism and intrusion due to melting of mantle and subjecting slab.

38
Q

___of sialic material with cont. crust / oceanic crust.

A

recycling

39
Q

What is the supercontinent cycle?

A
  • All of many contents collide forming large (or a single) continents – break up later on – cont. crust/cont. crust.
  • “stitching” and “accretion”
  • Really just a plate-tectonic driven megascale recycling – no volume added
40
Q 
Pangea = ~\_\_\_Ma
Rodina = ~\_\_\_Ga
Ur = ~ \_\_\_Ga
A

200-300 Ma

  1. 0 Ga
  2. 0 Ga
41
Q

How deep are most ocean trenches

A

8-12 km deep

42
Q

How deep will subduction go?

A

600 km max

G108 (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions