Adapted from a release written by Alison Auld for Dalhousie University
One published in Science Advances The first detailed image of the newly developed subduction zone near the coast of the Haida Gwaii Islands in British Columbia has been revealed.
International researchers gather data from the study during a 2021 cruise of the 2021 Lamont-Doherty Earth observation ship Marcus G. Langseth. They used 15km of underwater cables in the area near northern British Columbia, equipped with thousands of underwater microphones called water pipes (called speech) to map the deep structures below the Earth.
Their data confirm that the Queen Charlotte fault system can produce powerful giant earthquakes that can produce strong shaking and tsunamis.
In areas where one tectonic plate dives on another, in this case, the Pacific plate is found below the North American plate. The field is known for producing powerful tremors. In fact, the Queen Charlotte fault system represents Canada’s largest earthquake danger, causing the country’s largest recorded earthquake in 1949 and the famous earthquake in 2012 caused a tsunami.
“The region is actively becoming a subduction zone, so understanding the fault structure here tells us the early stages of subduction development,” said Collin Brandl, a postdoctoral research scientist at the Lamont-Doherty Earth Observatory, part of the Columbia Climate School. “Our study provides the first direct observation of the Haida Gwaii thrust, the “mega” of the system, which can help improve hazard analysis in the region, prepare residents for future earthquakes and tsunamis.”
Brandl’s co-author is part of an international team from the University of New Mexico, Western Washington University, U.S. Naval Research Laboratory, Boise State University, Dalhousie University in Nova Scotia, University of British Columbia, University of Victoria, University of Victoria, Canadian Geological Survey, Canadian Geological Survey and Geely University.
Media interviews with Collin Brandl can be arranged by emailing [email protected].
