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Conditions for Creation

A deep-sea volcanic eruption at Brimstone Pit, a vent on the side of a large submarine volcano in the Mariana Arc – part of the “Submarine Ring of Fire” that circles the Pacific Ocean basin, where tectonic plates spread or collide. Credit: NOAA Submarine Ring of Fire 2006 (Volcanoes Unit MTMNM)

A deep-sea volcanic eruption at Brimstone Pit, a vent on the side of a large submarine volcano in the Mariana Arc – part of the “Submarine Ring of Fire” that circles the Pacific Ocean basin, where tectonic plates spread or collide. Credit: NOAA Submarine Ring of Fire 2006 (Volcanoes Unit MTMNM)

By Simon Turner, Tracy Rushmer, Mark Reagan & Jean-Francois Moyen

A sequence of the world’s oldest rocks in the depths of the Mariana Trench indicates that both plate tectonics and life may have commenced on Earth 4.4 billion years ago.

The full text of this article can be purchased from Informit.

Plate tectonics is the process by which large parts of Earth’s outer plates slide past each other. This process of subduction causes the natural disasters we are all familiar with: earthquakes and volcanic eruptions. Subduction also created the continental crust upon which we live and cultivated a life-friendly environment for the Earth.

A key question that has long perplexed earth scientists is just when, during our planet’s 4.56 billion-year history, did this process begin? If the present is the key to the past then it could have been a very long time ago indeed. Unfortunately, rocks sufficiently ancient to test this hypothesis are exceedingly rare.

However, we have identified a sequence of the world’s oldest rocks in Canada that is almost the same as modern rocks formed deep beneath the ocean near the Mariana Trench. The discovery suggests that both plate tectonics, and even life itself, may have commenced 4.4 billion years ago – a billion years earlier than previously thought.

The discovery came after a major conference in San Francisco in December 2012, when I was having a drink with my friend and colleague Mark Reagan. He was describing a volcanic rock sequence between the Mariana islands and the Mariana Trench, and it sounded identical to very ancient volcanic rocks in northern Quebec that Tracy Rushmer had told me about. Tracy was undertaking...

The full text of this article can be purchased from Informit.