When was Snowball Earth and what is the Snowball Earth Hypothesis?
The Snowball Earth hypothesis proposes that during certain icehouse climates in Earth’s history, the entire planet’s surface became entirely or nearly entirely frozen, with no liquid oceanic or surface water exposed to the atmosphere. This global glaciation is believed to have occurred before 650 million years ago, during the Cryogenian period.
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First Snowball Earth Glaciation:
- The first significant glaciation event associated with the Snowball Earth hypothesis is known as the Sturtian glaciation.
- It occurred around 717 million years ago and lasted for at least five million years.
- During the Sturtian glaciation, the Earth experienced such extreme cooling that it transformed into a colossal snowball, with ice enveloping the entire surface from the poles to the Equator.
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Evidence and Impact:
- Sedimentary deposits believed to be of glacial origin have been found at tropical paleolatitudes, supporting the idea of global glaciation.
- The Snowball Earth episodes likely occurred before the sudden emergence of multicellular life forms known as the Cambrian explosion.
- The last significant Snowball Earth glaciation ended approximately 635 million years ago. During this period, the entire planet was covered in ice, marking a critical time in Earth’s history and profoundly impacting the evolution of life.
The Snowball Earth hypothesis was initially based on paleomagnetic studies worldwide. It was thought that the entirety of the Earth was frozen from pole to pole, solid to the equator. The indications for a Snowball Earth were that tropical glacial deposits have been found in equatorial paleo altitudes along with "dropstones" carried by glaciers.
There has been some debate about whether the Earth was entirely locked in ice or was something more akin to a "slush ball." There has been no definitive decision about how "locked" the Earth was in ice. Still, the theory hasn't been excluded and first merited the label "Snowball Earth" by Caltech geophysicist Joe Kirschvink in a 1992 research paper.
Cap carbonates have been figuring into the Snowball Earth theory since the '90s. These layered, laminated carbonate rocks are typically limestone or dolostone. Cap carbonates are found on top of tillites from glaciation and appear like a "cap" over them, hence the name. These remarkable rocks have been found worldwide coinciding with glacial intervals, which has helped them contribute to the Snowball Earth theory.
This specimen was recovered in the glacial till from the Espanola Formation, a part of the Huronian Supergroup of Canada, and is dated from 2400 mya to 2100 mya. The Huronian glaciation is considered the most intense and oldest ice age on Earth. The Huronian glaciation was a combination of several glaciations, occurring almost in succession.
Capstone carbonates were found in the deposits from the Huronian glaciation time frame. This specimen came from Ontario, Canada, and is from the first oldest ice age, the Huronian Ice Age. Some scientists believe that since some glacial till and cap carbonates are found together, along with other worldwide data, the Earth was mostly, if not entirely, covered in ice for the first time during the Huronian glaciation period.
Specimen size: 51mm L X 37mm W X 21mm D, Pictures shown front and back. It was legally obtained in a materials trade with a scientific institution.
Ships with information, tag, tag stand and Certificate of Authenticity. Acrylic base and cube are not included. Detailed information about the other snowball Earth glaciation events is included! Photo cube and plexiglass base not included.
If you have been looking for an epic specimen from one of Earth's most extreme environments, you need not look further. No other event depicts the extremes of climate change more than a Snowball Earth. This is a unique opportunity to obtain a scarce and exciting specimen from one of Earth's major geological events.