CONCEPT MAP

Duration

Interesting FacTs PT.1

InterestingFacTs PT.2

The Great Oxygenation Event (GOE)

What was the world like?

Maxwell, HockensteinGLY1030 9/29/24

Referencess

Mini-research project: Huronian Glaciation

The Huronian Glaciation lasted from approximately 2.4 to 2.1 billion years ago, making it one of the longest and most severe ice ages in Earth's history.

Duration

This occurred during the Paleoproterozoic Era.

Climate: During the Huronian Glaciation, the Earth experienced extreme cooling, with vast ice sheets covering much of the planet's surface. The global average temperature dropped a lot, and glaciers may have reached the equator in some areas.Atmosphere: Before this glaciation, the Earth's atmosphere had little to no oxygen. However during this time, oxygen levels began to increase due to the activity of cyanobacteria, leading to the "Great Oxygenation Event".(GOE) This rise in oxygen drastically changed the composition of Earth's atmosphere and triggered a lot of environmental shifts. Organisms: The dominant life forms were single-celled organisms like simple prokaryotes. Multicellular life had not yet evolved, and the increase in oxygen levels led to the mass extinction of many anaerobic organisms that couldn't survive in the new oxygen-rich environment.

What was the world like?

The Great Oxygenation Event was a really important event during this time. It happened when tiny organisms called cyanobacteria started making a lot of oxygen through photosynthesis. This changed the atmosphere, making it full of oxygen, but it also wiped out a lot of organisms that couldn’t live with oxygen, especially anaerobic bacteria. Scientists think that this rise in oxygen played a big part in causing the Huronian Glaciation. That’s because the increase in oxygen made methane, a powerful greenhouse gas, decrease, which led to the Earth cooling down a lot.

The Great Oxygenation Event (GOE)

First Major Ice Age: The Huronian Glaciation was Earth's first known major ice age, and it is considered to be one of the most severe. It is said that this may have led to a "Snowball Earth" scenario, where ice covered almost the entire surface of the planet. Oxygen Poisoning: The rise of oxygen levels was toxic to many existing life forms at the time, particularly anaerobic bacteria, which could not survive in an environment full of oxygen. Banded Iron Formations: The Huronian Glaciation happened at the same time as the formation of banded iron formations, which are sedimentary rocks with layers of iron and silica. These rocks show that oxygen was reacting with iron dissolved in the oceans, causing the iron to settle out as iron oxides.

InterestingFacts PT.1

Frozen Equator: Some scientists believe that the glaciation was so extreme that ice sheets reached the equator, potentially freezing most of the planet’s surface. Geological Evidence: Evidence of the Huronian Glaciation comes from ancient glacial deposits, which are found in places like Canada and South Africa, indicating that glaciers once existed in these places. End of Anaerobic Dominance: The Huronian Glaciation and the GOE marked the end of the dominance of anaerobic organisms and paved the way for the evolution of aerobic life forms, which would eventually lead to a more complex life.

Interesting Facts PT.2

Schopf, J. W. (2006). "The Paleoproterozoic Era and the Huronian Glaciation: Impacts on Life's Evolution." Journal of Paleobiology. Bekker, A., Holland, H. D., Wang, P. L., Rumble, D., & Stein, H. J. (2004). "Dating the rise of atmospheric oxygen." Geological Society of America.

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