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Thu October 17, 2013
Dr. Lloyd White, Royal Holloway University - Reconstructing Gondwana
In today’s Academic Minute, Dr. Lloyd White of Royal Holloway University discusses revisions to the map of the supercontinent Gondwana.
Lloyd White is a postdoctoral research fellow in the Department of Earth Sciences at Royal Holloway University in Surrey, England. His research interests include tectonics, geochronology, and structural geology. He is currently investigating the history of plate movement in Southeast Asia as well as the regional geology of Sulawesi and the Bird's Head peninsula.
Dr. Lloyd White - Reconstructing Gondwana
The Earth’s surface (or “crust”) is like a thick hard layer of scum floating above a much hotter and denser layer that we call the mantle. The mantle is extremely hot, so much so that it convects and deforms causing the thick crust above it to crack and move. We refer to these cracked bits of crust as “tectonic plates”, and they have been floating about the Earth’s surface for billions of years. This means that the configuration of the Earth is always changing. Which also means that if we could travel back in time a map of the world would look totally different to what it does today.
At one point in time, what we now know as Africa, South America, India, Australia and Antarctica were joined together as part of a supercontinent we call Gondwana. My colleagues and I have been working on ways to assess the models that show what this supercontinent looked like before it broke apart. Our tests revealed that some of the most recent attempts to reconstruct Gondwana positioned the Australian plate several hundred kilometres too far to the east.
The problem with this is that these ancient maps are typically built by moving one plate relative to another one. So, the incorrect positioning of one plate will lead to the error being propagated around the globe. For example, we showed how this error affected the positioning of India and Antarctica, as this has implications for topics like understanding when India collided with Eurasia to produce the Himalayan mountain range.
While this might all seem esoteric to some, these models are often used to help understand the history of hydrocarbon bearing regions and in determining the migration pathways of ancient plants and animals. Just imagine if your GPS had this kind of precision, where in the world might it tell you, you are, what kind of problems might this lead to?