Archean Events
4.0 billion to 2.5 billion years
What is the time frame of the Archean Eon?
The gas that caused Banded Iron Formations to form.
What is oxygen?
These three cycles are related to Earth's orbit and rotation.
What are Milankovitch cycles?
When all or most continents are brought together by plate tectonics.
What is a supercontinent?
A complex cell with DNA in a nucleus and organelles.
What are eukaryotes?
When this smashing space event ended, the Archean Eon could begin.
What is the Late Heavy Bombardment?
These rocks that indicate warm weather and shallow seas were deposited on top of Snowball Earth ice age rocks, like a hat.
What are cap carbonates?
Sturtian (~717 myr ago) and Marinoan (~650 myr ago).
What are Snowball Earth ice age episodes.
It would one day be called North America.
What was Laurentia?
The first macroscopic animals, were soft, sedentary, and most were evolutionary dead-ends.
What are the Ediacara animals?
Colonies of cyanobacteria form thick, layered mats and produce oxygen.
What are stromatolites?
The Meso-Proterozoic supercontinent.
What is Rodinia?
Ice reflects sunlight, which cools the climate, which leads to more ice, which cools the climate more…..and on and on.
What is a positive feedback loop?
Ancient mini continents still found within todays continents.
What are cratons?
No fossils exists, but it's the probable first living thing on Earth.
What is RNA (World)?
This produced 70-75% as much energy in the Archean.
What is the Sun?
Added a big piece to SW North America between 1.8 and 1.6 byr. ago.
What was the Yavapai-Mazatzal orogeny?
Iron, uranium, and sulfur minerals are not oxidized in Archean sediments.
What is evidence for low oxygen?
Rock that formed on land that show there was abundant free oxygen in the atmosphere.
What are continental red beds?
Bacteria and Archaea.
What are the two types of prokaryotes?
The 3.4 billion year old Strelley Pool fossils.
What are the oldest microfossils ever found?
1.0 byr. – 542 myr.
What was time of the NeoProterozoic?
Sediments that are made by glaciers. Evidence for the "Snowball Earth" and other ice ages.
What are tillites?
Iron (Fe2+) that dissolves in water, when there is no oxygen present.
What is "ferrous" iron?
Prokaryotes merged and mutually benefitted each other, eventually became eukaryotes with nucleus and organelles.
What is endosymbiosis?