My Notes for Unit 4

Question 1

What are the 3 parts of geological time?

Answer 1

1) Relative Time
2) Absolute Time
3) Geological Time Scale

Question 2

What is dating?

Answer 2

The procedures we use to:

i. determine when an event took place, and
ii. determine the sequence of events

Question 3

What is the age of rocks?

Answer 3

the time it was emplaced

Question 4

What is deep time?

Answer 4

• very old events

- very old rocks

Question 5

What is relative geological time?

Answer 5

• The sequence of processes that have occurred at some location
• We can see this with the naked eyes – or work it out with fairly simple geological observations.

Question 6

What is age sequence?

Answer 6

One process took place after another

Question 7

What is stratigraphic succession?

Answer 7

Shows a superposition of rocks (old below young) –> layers of rock

Question 8

What is magma?

Answer 8

general name for liquid rock under ground

Question 9

What is lava

Answer 9

name for liquid rock above ground

Question 10

What are anticline and syncline a part of?

Answer 10

tilting (deformation and angular unconformity)

Question 11

What is a normal fault?

Answer 11

Body of rock above fault has gone downwards (bottom side “footwall block”) and body below has gone upwards (topside “hanging-wall block).

Question 12

What is the opposite of a normal fault?

Answer 12

thrust fault

Question 13

what is iodine?

Answer 13

syncline and anticline

Question 14

What is stratigraphic facing?

Answer 14

The upwards movement of young rocks

Question 15

What does the topographic sequence of unconformity represent?

Answer 15

passing of time

Question 16

What is metamorphism?

Answer 16

Newer crystals form in roc and metamorphic rock becomes crystallized as well (for nonconformity)

Question 17

___million years ago life became common.

Answer 17

540

Question 18

How long has fossil correlation been useful for?

Answer 18

Only for about the last 500 or so million years.

Question 19

What is fossil range?

Answer 19

timespan an organism exists.

Question 20

On average, how long does a species exist for?

Answer 20

6 million years

Question 21

Time ranges___for different species.

Answer 21

overlap

Question 22

When looking at fossils records in rocks, we find___.

Answer 22

gaps

Question 23

Fossils have specific geological___.

Answer 23

ranges

Question 24

___ages are “add ons” and can change (improve) from time to time.

Answer 24

absolute

Question 25

What is the oldest fossil found on earth?

Answer 25

stromatolites (blue-green algae / cyanobacteria)

Question 26

When was the birth of stromatolites?

Answer 26

3.5 - 3.8 mya

Question 27

Stromatolites appeared during the___explosion.

Answer 27

Cambrian

Question 28

What was the first sexual reproduction between?

Answer 28

stromatolites (blue-green algae)

Question 29

Up to how high can stromatolites grow to be?

Answer 29

~ 1 m

Question 30

What are stromatolites composed of?

Answer 30

CaCO3

Question 31

What are CaCO3 “houses”?

Answer 31

Stromatolites

Question 32

What is the biggest ice age on Earth known as?

Answer 32

Snowball Earth

Question 33

What is Greenhouse Earth?

Answer 33

hot

Question 34

The Earth’s temp bounces back and forth between?

Answer 34

Snowball Earth and Greenhouse Earth

Question 35

What was the temp when the T-Rex arrived?

Answer 35

+23 degrees C

Question 36

What is the global average temp?

Answer 36

+17 degrees C

Question 37

How can we work out the atmospheric temperature?

Answer 37

mainly oxygen isotopes and other isotopic studies

Question 38

What was the temp during the 300-250 (approx. 251) ice age?

Answer 38

-5 degrees C

Question 39

When was Snowball Earth?

Answer 39

during the precambrian

Question 40

When was there glaciation in Canada?

Answer 40

during the precambrian