Geologic Periods

Question 1

Cambrian

Answer 1

541-485 MYA - 1st of Paleozoic Era - Named after Wales - Cambrian Explosion of life forms

Question 2

Precambrian

Answer 2

4.6 BYA (Earth formation) - 541 MYA - Accounts for 88% of geologic time - Little knowledge and fossils - Stromatolites and bacteria

Question 3

Ordovician

Answer 3

485-444 MYA - 2nd of Paleozoic Era - Named after British Ordovices tribe - Molluscs, arthropods, early fish - Ended with major extinction event

Question 4

Silurian

Answer 4

444-419 MYA - Named after British Silures tribe - Jawed and bony fish - Very beginning of terrestrial life

Question 5

Devonian

Answer 5

419-359 MYA - Named after Devon, England - Beginning of the “Age of Fish” - First spread of land animals and forests

Question 6

Carboniferous

Answer 6

359-299 MYA - Means “coal bearing” - Many coal beds created during this time - Amphibians, insects, and forests thrived - Pangaea formed

Question 7

Permian

Answer 7

299-252 MYA - Last period of Paleozoic era - Ended with largest mass extinction in Earth’s history, in which nearly 90% of marine species and 70% of terrestrial species died out - Pangaea surrounded by ocean Panthalassa - Named for medieval Kingdom of Permia in Russia

Question 8

Triassic

Answer 8

250-209 MYA - 1st period of the Mesozoic Era (the “Age of Reptiles”) - Named for three rock layers found in Germany - 1st true mammals - Life slowly recovering after Permian Extinction

Question 9

Jurassic

Answer 9

201-145 MYA - Dinosaurs dominant, 1st birds - Pangaea splits into Laurasia y Gondwana - Interior deserts replaced by lush rainforests - Named after Jura Mtns in the Alps

Question 10

Cretaceous

Answer 10

145-66 MYA - From the Latin “creta” (chalk) - Last of Mesozoic - Longest period at 79 mil - Dinos, mammals, birds, flowering plants - Ended with extinction of dinosaurs

Question 11

Paleogene

Answer 11

66-23 MYA - 1st of Cenozoic Era - Explosion of mammals

Question 12

Neogene

Answer 12

23-3 MYA - 2nd of Cenozoic - Mammals and birds develop - 1st ancestors of humans in Africa

Question 13

Quarternary

Answer 13

3 MYA to present - The current geologic period - 3rd of Cenozoic Era

Question 14

Mnemonic for geological periods y epochs

Answer 14

Certain Old Sedimentary Deposits
Can Move Pure Paleontologists
To Jaunty Celebration,
Prodigious Excavation,
Or Madly Preposterous Postulation. Ha!

Cambrian, Ordovician, Silurian, Devonian,
Carboniferous [Mississippian y Pennsylvanian], Permian, Triassic, Jurassic, Cretaceous,
(then into epochs of the Cenozoic, not periods) Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, Holocene