Geology of early Earth

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Geology of early Earth


This is a transcript of a QuickTime movie (14 MB) recorded in the Pilbara in 2005. Adrian Brown, from the Australian Centre for Astrobiology, talks about the geology of the early Earth.

Transcript:

We don't have many examples of rocks that survived the time from 3.5 billion years ago. So when geologists visit the Pilbara they know that these rocks have been through so much time, so much attention from the atmosphere and water eroding them and working them down. So they are interested in the way that these rocks look, and they are interested in the way that processes happened to form these rocks on the early Earth. Because they really show us a story about an earth that is very different from the one we have today. It probably didn’t have any plate tectonics, probably didn’t have the sort of continents that we have, that we live on today, probably didn’t have the same deep oceans that we have today, probably didn’t have the same huge mountains like Mt. Everest and the Himalayas that we have today. It probably would have been a very low laying earth, it probably would have had minor amounts of crust, perhaps maybe 5-10% of what we have today. But at this stage the only way that we can find out more about that sort of thing is by looking at these really old rocks, that's why geologists get excited because they know that for them it is just like reading the book of Genesis, this is the first book, this is the early pages of the earth. And the most important ones as far as the starting of geology and perhaps the starting of life.


Contents


Introduction

Context

Early Life

Evidence

Acknowledgements

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