Scientists
are a step closer to predicting when and where earthquakes will occur
after taking a fresh look at the formation of the Andes, which began 45
million years ago.
Published recently in Nature,
research led by Dr. Fabio Capitanio of Monash University’s School of
Geosciences describes a new approach to plate tectonics. It is the first
model to go beyond illustrating how plates move, and explain why.
Capitanio said that although the theory had been applied only to one plate boundary so far, it had broader application.
Understanding
the forces driving tectonic plates will allow researchers to predict
shifts and their consequences, including the formation of mountain
ranges, opening and closing of oceans, and earthquakes.
Capitanio
said existing theories of plate tectonics had failed to explain several
features of the development of the Andes, motivating him to take a
different approach.
“We
knew that the Andes resulted from the subduction of one plate, under
another; however, a lot was unexplained. For example, the subduction
began 125 million years ago, but the mountains only began to form 45
million years ago. This lag was not understood,” Capitanio said.
“The
model we developed explains the timing of the Andes formation and
unique features such as the curvature of the mountain chain.”
Capitanio
said the traditional approach to plate tectonics, to work back from
data, resulted in models with strong descriptive, but no predictive
power.
“Existing
models allow you to describe the movement of the plates as it is
happening, but you can’t say when they will stop, or whether they will
speed up, and so on.
“I
developed a three-dimensional, physical model. I used physics to
predict the behaviour of tectonic plates. Then, I applied data tracing
the Andes back 60 million years. It matched.”
Collaborators
on the project were Dr. Claudio Faccenna of Universita Roma Tre, Dr
.Sergio Zlotnik of UPC-Barcelona Tech, and Dr. David R Stegman of
University of California San Diego. The researchers will continue to
develop the model by applying it to other subduction zones.
Subduction dynamics and the origin of Andean orogeny and the Bolivian orocline