Lecture 19

Question 1

Who created the map that changed the whole world?

Answer 1

Sir William Smith-first geological map realized on a whole country.

Question 2

How did Sir William Smith create his map?

Answer 2

Noted that limestone layers are younger versus older. Combined rock record with fossils in these rocks. Fossils have stratigraphical layers.

Question 3

What are index fossils?

Answer 3

Fossils that can be used for dating the layers. Could be correlated with other stratigraphical layer

Question 4

What is the Principle of Biological Succession (Sir William)

Answer 4

Once something goes extinct, it does not live again. Fossil record in Earth’s history is not repeatable, gradual change from oldest fossil till current

Question 5

What did William Smith regard the fossil record as?

Answer 5

A sign of continuous divine creation (last creationist to have a say in science).

Question 6

What was the main question that formed the principle of inclusion? (Charles Lyle)

Answer 6

Worked with primarily sedimentary rocks. Wondered if we can include metamorphic and igneous rocks in the same way?

Question 7

What is the principle of inclusion?

Answer 7

Inclusion (rock inside of another rock), is older than the one it’s embedded in. Older rock is situated both above and below. Cannot apply principle of superposition.

Question 8

What is the Principle of Cross cutting relations (igneous rocks)

Answer 8

Dikes that cut through rocks are younger than the one that they cut through

Question 9

What are the relative ages of lava flows?

Answer 9

Lava flow cooks the preexisting rocks. Flow is younger than both the rocks below and above. Cooked rock between sedimentary rocks is younger than both above and below. Igneous rocks are injected between sedimentary rocks (Sill)

Question 10

What are the 4 eons that earth is divided in (in stratigraphical order).

Answer 10

Hadean, Archean, Proterozoic, Phanerozoic.

Question 11

What was the Hadean Eon?

Answer 11

Earth is a globe of molten matter (no rock record). Can correlate with Solar Nebula Theory

Question 12

What was the Archean Eon?

Answer 12

Contains the oldest rocks we know, from the North West Territories and Quebec

Question 13

What is the Proterozoic Eon?

Answer 13

Includes rocks with earliest life forms (even though life appeared in the Archean). Onsent of plate tectonics. Movement went from vertical to horizontal. Change was gradual. Mostly small sized, single celled organisms (microbes)

Question 14

What is the Phanerozoic era?

Answer 14

Vast number of large sized fossils, no microbes.

Question 15

When did the Cambrian Explosion happen?

Answer 15

In the boundary between the proterozoic and phanerozoic

Question 16

What was the Cambrian Explosion?

Answer 16

Organisms in oceans began to dig in sediments. New food sources created complex body forms. Nutrients in oceans increased, large organisms evolved. No predators existed yet. Lots of skeletons.

Question 17

Why is it hard to separate Archean and Proterozoic rocks?

Answer 17

Often affected by metamorphism.

Question 18

What is the Super Eon Level?

Answer 18

Precambrian groups. Rocks are “full body texture”

Question 19

What are the 3 subdivisions of the Phanerozoic?

Answer 19

Eras: Paleozoic, Mezozoic, Cenozoic

Question 20

What is the Paleozoic?

Answer 20

Life forms with little resemblance to modern life forms

Question 21

What is the Mezozoic?

Answer 21

Life forms with resemblance to modern ones (ex: Conifers, Angeospore evolution, continental floras almost the same as today.

Question 22

What is the Cenozoic?

Answer 22

Life forms with strong resemblance to those today.

Question 23

What was the lower paleozoic boundary?

Answer 23

When the Cambrian Explosion happened

Question 24

When did the most severe change to Earth happen?

Answer 24

In between the palaeozoic and Mesozoic

Question 25

What happened in between the paleozoic and Mesozoic?

Answer 25

Oceanic current, changes water between oceans. Oceanic conveyor collapsed and turned into a stagnating swamp. Incredibly warm. 90% of species went extinct. Conveyer then restarted and life resumed.

Question 26

What was the 2nd crisis that happened in between the Mesozoic and Cenozoic?

Answer 26

The Great Dying

Question 27

What was the Great Dying?

Answer 27

When a meteorite impact created a crater in Mexico. Caused the extinction of dinosaurs and large oceanic reptiles and flying reptiles. Mammals took over.

Question 28

When did Primates first appear?

Answer 28

Late mezozoic.

Question 29

What are the 6 periods of the Paleozoic Era?

Answer 29

Cambrian, Ordovisian, Celurian, Devonian, Carboniferus, and Permean

Question 30

What can the Carboniferus period be subdivided into (only in North America)

Answer 30

Mississippian and Pennsylvanian.

Question 31

What are the 3 periods of the Mezozoic Era?

Answer 31

Triasic, Jurassic, and Crustaceous (Dinosaur Time)

Question 32

What are the 3 periods of the Cenozoic?

Answer 32

Paleogene, Neogene, and Quaternary