lecture 04: lithosphere and earth's history up to the quaternary period

Question 1

when did the big bang happen

Answer 1

~13.8 billion years before present (YBP)

Question 2

when did our solar system and sun form?

Answer 2

~5 Ga (~9 Ga after the big bang)

Question 3

how long ago did earth form

Answer 3

4.5 Ga

Question 4

theia impact

Answer 4

theorized, mars sized object impaction forms the moon 4.5 Ga

Question 5

lithosphere

Answer 5

solid outer part of earth including the crust and the upper part of the mantle

Question 6

what periods are in the paleozoic era

Answer 6

cambrian, ordovician, silurian, devonian, carboniferous, permian

Question 7

what periods are in the mesozoic era

Answer 7

triassic, jurassic, cretaceous

Question 8

what are the eras

Answer 8

precambrian, paleozoic, mesozoic, cenozoic

Question 9

what period are we in now

Answer 9

quaternary

Question 9

what epoch are we in now

Answer 9

holocene

Question 10

when did the earths continents start forming

Answer 10

~3 Ga

Question 10

what is the canadian shield

Answer 10

large exposed area of igneous and metamorphic rock

Question 11

how did the continents form

Answer 11

planet was hot and convection was vigorous in the mantle. rocks rose to the surface forming the lithosphere

Question 12

cratons

Answer 12

floating pieces of the lithosphere that stopped growing around 2 Ga as earth was cooling

Question 13

modern ear of plate tectonics

Answer 13

added new margins to the original cratons, expanding the continents

Question 14

north american cratons

Answer 14

superior, slave, churchill, wyoming

Question 15

mesozoic era

Answer 15

252-66 Ma
middle-life
began at the permian-triassic extinctino event 252 Ma and was the earth’s most severe extinction event

Question 16

triassic period

Answer 16

252-201 Ma
recovery of extinction period, breakup of pangea, expansion of dinosaurs and gymnosperms

Question 17

jurassic period

Answer 17

201-145 Ma
more tropical and humid, expansion of seas, dinosaurs begin to dominate, first true mammals evolve

Question 18

cretaceous period

Answer 18

145-66 Ma
more expansion of seas, more seasonality, birds developing, volcanic eruptions affecting atmosphere, much of alberta’s bedrock deposits

Question 19

sedimentary basin

Answer 19

thick area of the earth where the crust is underlain by a thick sequence of sedimentary rocks

Question 20

what are the layers of rocks called

Answer 20

beds

Question 21

what are the boundaries separating beds of rocks called

Answer 21

contacts

Question 22

k-t boundary

Answer 22

point between creatceous and tertiary periods where large dinosaurs disappeared and the boundary in rock sediments had high concentrations of iridium

Question 23

luis and walter alvarez

Answer 23

studied the boundary and determined the impactor based on iridium amounts spanned at least 10km in diameter

Question 24

canadian rockies

Answer 24

formed mostly from sedimentary rock in the late paleozoic era and uplifted 185 Ma to 55 Ma

Question 25

what do u-shaped valleys indicate on mountains

Answer 25

that they were shaped by glaciers

Question 26

what percentage do mountains make up the earths surface

Answer 26

30%