The world's longest mountain chain stretches along the entire west coast of South America, but scientists have been struggling to explain how it formed.
Published Dec. 1 in Nature, research led by Fabio Capitanio of Monash University's School of Geosciences, Dave Stegman of Scripps Institution of Oceanography at UC San Diego and others
describes new results of computer simulations showing how mountain ranges are built by plate tectonics.
Capitanio said existing theories of plate tectonics had failed to explain several features of how the Andes came into existence, and this motivated the researchers to develop a new approach. Capitanio said the traditional approach to plate tectonics, to work back from data, resulted in models with strong descriptive, but no predictive power.
"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."
"The formation of the Andes has been a long-standing question, but almost all of the previous explanations have major flaws. This new model is much more viable, but needs further testing," said Dave Stegman, a geoophysicist at Scripps Institution of Oceanography at UC San Diego.
The new theory has only been applied to one subduction zone so far, but has broader applications.
Understanding the forces driving tectonic plates will ultimately allow researchers to predict shifts and their consequences, including the formation of mountain ranges, opening and closing of oceans, and earthquakes.
Collaborators on the project also included Claudio Faccenna of Universita Roma Tre and Sergio Zlotnik of UPC-Barcelona Tech. The researchers will continue to develop the model by applying it to other subduction zones. Stegman's research was supported by the G. Unger Vetlesen Foundation.
Scripps Institution of Oceanography at the University of California San Diego, is one of the oldest, largest, and most important centers for global science research and education in the world. Now in its second century of discovery, the scientific scope of the institution has grown to include biological, physical, chemical, geological, geophysical, and atmospheric studies of the earth as a system. Hundreds of research programs covering a wide range of scientific areas are under way today on every continent and in every ocean. The institution has a staff of more than 1,400 and annual expenditures of approximately $195 million from federal, state, and private sources. Scripps operates oceanographic research vessels recognized worldwide for their outstanding capabilities. Equipped with innovative instruments for ocean exploration, these ships constitute mobile laboratories and observatories that serve students and researchers from institutions throughout the world. Birch Aquarium at Scripps serves as the interpretive center of the institution and showcases Scripps research and a diverse array of marine life through exhibits and programming for more than 430,000 visitors each year. Learn more at scripps.ucsd.edu and follow us at Facebook, Twitter, and Instagram.
About UC San Diego
At the University of California San Diego, we constantly push boundaries and challenge expectations. Established in 1960, UC San Diego has been shaped by exceptional scholars who aren’t afraid to take risks and redefine conventional wisdom. Today, as one of the top 15 research universities in the world, we are driving innovation and change to advance society, propel economic growth, and make our world a better place. Learn more at www.ucsd.edu.