Category Archives: Archean

Lots of oxygen on the Archean Earth?

Posted on September 2, 2009 by Chris Rowan

New evidence for the early evolution of photosynthesis: was the early Earth really as oxygen-free as we think it was?
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Categories: Archean, geochemistry, geology, paper reviews, past worlds, rocks & minerals

Geopuzzle #12 (finally) revisited

Posted on June 24, 2008 by Chris Rowan

The answer? I dunno…
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Categories: Archean, geology, geopuzzling, past worlds

What’s up with those Archean sandstones?

Posted on May 7, 2008 by Chris Rowan

In addition to searching out evidence for Archean microbial mats, my revisitation of the Pongola sandstones gave me the chance to look a bit more closely at their lithology. When I last posted pictures from this sequence, there was a … Continue reading →

Categories: Archean, fieldwork, geology, geopuzzling, past worlds

Archean bacterial mats under the hammer

Posted on May 6, 2008 by Chris Rowan

Geovandalism rears it’s ugly head once more.
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Categories: Archean, fieldwork, fossils, geology, paper reviews, past worlds, ranting

Sadly, not sandworms

Posted on January 28, 2008 by Chris Rowan

The answer to Friday’s geopuzzler
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Categories: Archean, fossils, geology, past worlds, Proterozoic

How the air we breathe became breathable

Posted on November 15, 2007 by Chris Rowan

What geology tells us about the evolution of the Earth’s atmosphere.
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Categories: Archean, geochemistry, geology, paper reviews, past worlds, Proterozoic

Where the Moon was at, 3.2 billion years ago

Posted on July 13, 2007 by Chris Rowan

It may not look particularly cosmic, but the rock below not only tells us that the Moon was present back in the Archean, but also that it was orbiting the Earth at a much closer distance than it is today.

Categories: Archean, geology, paper reviews, past worlds