Environment

A Map That Fills A 500-Million-Year Gap In Earth’s History

The Conversation

Earth is estimated to be around 4.5 billion years old, with life first appearing around 3 billion years ago.

To unravel this incredible history, scientists use a range of different techniques to determine when and where continents moved, how life evolved, how climate changed over time, when our oceans rose and fell, and how land was shaped. Tectonic plates – the huge, constantly moving slabs of rock that make up the outermost layer of the Earth, the crust – are central to all these studies.

Along with our colleagues, we have published the first whole-Earth plate tectonic map of half a billion years of Earth history, from 1,000 million years ago to 520 million years ago.

We now have a map of plate tectonics for the period 1,000-520 million years ago. The colours refer to where the continents lie today. Light blue = India, Madagascar and Arabia, magenta = Australia and Antarctica, white = Siberia, red = North America, orange = Africa, dark blue = South America, yellow = China, green = northeast Europe.

The time range is crucial. It’s a period when the Earth went through the most extreme climate swings known, from “Snowball Earth” icy extremes to super-hot greenhouse conditions, when the atmosphere got a major injection of oxygen and when multicellular life appeared and exploded in diversity.

Now with this first global map of plate tectonics through this period, we (and others) can start to assess the role of plate tectonic processes on other Earth systems and even address how movement of structures deep in our Earth may have varied over a billion year cycle.

The Earth moves under our feet

The modern Earth’s tectonic plate boundaries are mapped in excruciating detail.

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Modern plate tectonic boundaries. But how do we map the Earth like this in the past? NASA’s Earth Observatory

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