Dynamic Planet Scioly Div. B Glacial Ages

is the Pongola Glaciation real?

It was hypothesized

When did the Pongola Glaciation last?

2.9-2.8 billion years ago

When did the Huronian Glaciation last?

2.45bil-2.1bil years ago

In what event is the Huronian Glaciation in?

One of the two hypothesized Snowball Earth events

What was the Huronian Glaciation caused by?

the Great Oxeygenation Event

What was the Great Oxeygenation Event?

A time when the first photosynthesizing cyanobacteria released tons of oxeygen into the air; causing the chemical composotion to change.

What was the Cryogenian glaciation referred to?

One of the Snowball Earths

What was a popular idea of the amount of ice there was during the Cryogenian glaciation?

There was a “slushball earth”, with some equatorial ocean

When was the Sturtian Glaciation?

717 Ma-660 Ma ago

What caused the Sturtian Glaciation?

The result of the breakup of continents, specifically Rodinia.

Why would the breakup of continents cause glaciations?

The formation and weathering of crust would use of C02, causing a cooler climate

How did the Sturtian Glaciation end?

A result of a buildup of greenhouse gasses

When did the Matinoan Glaciation last?

650 Ma ago to 635 Ma ago

What caused the Matinoan Glaciation?

high weathering rates of new rocks being formed during the breakup of Rodinia.

What ended the Marinoan Glaciation?

the decline was believed to be because of the steady return of C02 levels

What Glaciations were in the Ediacaran Glaciations?

The Gaskiers Glaciation, and the Baykonurian Glaciation

When did the Gaskiers Glaciation last?

579.88 - 579.63 Million years ago; It lasted 250000 years

When did the Baykonurian Glaction last?

547 - 541.5 million years ago

Did the Baykonurian Glaciation cover both hemispheres?

Yes

When would the Kaigas glaciation have lasted?

780 - 730 Ma ago

Why were the two pieces of evidence towards the Kaigas glaciation false?

One was recalculated to be from the Late Sturtian Glaciation, and the other was determined to be non-glacial.

When did the Ordovician-Silurian Glaciation last?

458.4 - 430.5 million years ago

Where was the glaciation centered around?

The mondern-day Sahara Desert

What causes started the Ordovician-Silurian Glaciation?

1. Large amounts of volcanic activity; The weathering of the large amount of new basaltic rock would’ve decreased C02

2. Spread of moss-like plants taking in C02

3. The supercontinent Gondwana drifting over the south pole

4. The ordovician metoer event that likely left dust that reflected sunlight

5. Possibly Milankovitch Cycles

When did the Late Ordovician Glaciation last?

458.4 - 443.8 million years ago

Mostly, where was the Late Ordovician Glaciation?

The southern hemisphere

Whata are the two main suspects for the collapse of the Late Ordovician Glaciation?

1. Ice sheet collpase

2. Return of C02 levels

How many glaciations have been dated to the Early Silurian?

4

When did the Early Silurian Glaciation last?

443.8 - 430.5 million years ago