Ancient geologic events may have left deep 'scars' that can play a crucial role in earthquakes, mountain formation, and other ongoing geomorphological processes on our planet, says a new study.
These multi-million-year-old geological structures, situated at sites away from existing plate boundaries, may trigger changes in the structure and properties at the surface in the interior regions of continents.
"This is a potentially major revision to the fundamental idea of plate tectonics," said study lead author Philip Heron from University of Toronto.
"It's based on the familiar global tectonic map that is taught starting in elementary school," said co-author Russell Pysklywec, who is also chair of University of Toronto's department of earth sciences.
"What our models redefine and show on the map are dormant, hidden, ancient plate boundaries that could also be enduring or 'perennial' sites of past and active plate tectonic activity," he added.
The team used Toronto's SciNet -- Canada's most powerful computer and one of the most powerful in the world -- to make numerical models of the crust and upper-mantle into which they could introduce ancient scar-like anomalies.
Using these models, the researchers found that different parts of the mantle below the Earth's crust may control the folding, breaking, or flowing of the Earth's crust within plates -- in the form of mountain-building and seismic activity -- when under compression.