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Flashcards in Midterm Exam File Questions Deck (41)
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1
Q

The largest of the “rocky” or terrestrial planets is…

A

Earth

2
Q

The most abundant three elements within Earth are

A

iron, oxygen, and magnesium

3
Q

Bodies in our solar system grew by the colliding of millions of bits of matter, this process is called

A

accretion

4
Q

As one result of accretion, bodies larger than about 500 km in diameter became very hot, perhaps molten, resulting in a gravity driven separation of material with different dentition. This is called…

A

differentiation

5
Q

The portion of Earth that is broken into tectonic plates is the

A

lithosphere

6
Q

Orogenic mountains form at or near

A

colliding plates

7
Q

The very first stars in the history of our universe would have differed from our sun (Sol) in that

A

they were larger and contained little except hydrogen and helium

8
Q

Small bodies of rock or metal that orbit Sol are called

A

asteroids

9
Q

Objects made of a mixture of ice and rock that orbit Sol are called

A

comets

10
Q

EArth’s lithosphere is composed of the

A

all of the crus and uppermost 100-150 km of mantle

11
Q

The Moho is the base of EArth’s

A

crust

12
Q

the age of oceanic crust___with increasing distance from the mid ocean ridges

A

increases

13
Q

The oldest lava (basalt) on the sea floor is about___

A

200 Ma

14
Q

Continental coastlines that occur within the interior of a tectonic plate are called

A

passive margins

15
Q

When rock is melted within the earth, resulting in volcanic activity, which statement is true about the melting

a) all material is melted
b) only a portion of the rock is melted–partial melting

A

b

16
Q

Melting at divergent plate boundaries is partly the result of

A

reduction of pressure

17
Q

Volcanic arcs have a direct geological relationship to

1) subduction
b) plate collision
c) oceanic trenches
d) all 3 of the above
e) none of the above

A

d

18
Q

A massive continental-scale glacier covered southern India and much of the land now south of the equator during the later part of the___Era

A

Palaeozoic Era

19
Q

Which is the oldest unit of the Geological Time Scale

A

Hadean

20
Q

Which is the youngest unit of the Geological Time scale

A

Cenozoic

21
Q

The oldest life forms on planet Earth lived during which time unit?

A

Archean

22
Q

Th last of the 3 major extinction events on Earth occurred at about

A

65 Ma

23
Q

The most significant of the 3 major mass extinction events on Earth occurred at about

A

245 Ma

24
Q

The process of plate tectonics results from___in EArth’s mantle

A

convection

25
Q

Which of the following is true about EArth’s mantle

A

It is solid except for small liquid patches

26
Q

Evidence indicates that Earth is about___old

A

4.5 Ga

27
Q

Modern astronomy indicates that the Big-Bang occurred at about

A

14 Ga

28
Q

One of the most important processes to take place after the Big-Bang and before the formation of our solar system was

A

the fusion of atoms inside large suns

29
Q

The condition of floating equilibrium of the lithosphere in the rest of the mantle is called

A

isostasy

30
Q

Although high variable, the average rate of movement of Earth’s tectonic plates is approximately

A

2 cm/year

31
Q

The deepest parts of the oceans occur

A

at convergent plate countries

32
Q

An isotope is

A

an atom with a specific number of protons plus a specific number of neutrons in its nucleus

33
Q

What is the depth of the base of oceanic crust

A

8 km

34
Q

What is the mantle/core boundary depth

A

2900 Km

35
Q

what is the centre of Earth depth

A

6400 km

36
Q

Earth’s asthenosphere is

A

a zone of weak roc in the lower part of the upper mantle

37
Q

the rate of 15O to 16 O in the shell of a marine planktonic organism can be used to determine

A

the temperature of the water in which the organism lived

38
Q

the most common type of meteorite (by far) is what is called ‘an ordinary chondrite’ One reason why their study is important to us is that

A

they seem to have the same chemical composition as Earth overall

39
Q

Regarding eArth’s atmospheric temperature (climate): in the geological past it has

A

fluctuated numbers times between ice ages and much water periods

40
Q

In the chemical classification of igneous rocks, which material is the most important

A

the silica content

41
Q

Imagine the following geological situation,a s determined fro a groups of rock strata in a tectonic mountain belt. A sequence of horizontal beds of clay and sandstone overlie a series of folded lava flows, displaying a number of anticlines an disinclines. The lava beds are all approximately 100 to 90 Ma, and the oldest of the sedimentary layers of 50 Ma, the youngest 35 Ma. The boundary between the lava and the sedimentary beds is called a (an)

A

angular unconformity