Geoscientists explore origins of Mackenzie Mountains

When geologists at Colorado State University look west toward the Rocky Mountains they stare into the face a fundamental geologic question: How do some major mountain ranges form at great distances from plate tectonic boundaries? The Colorado Rocky Mountains were uplifted between 80 to 55 million years ago while the Pacific-North America plate boundary was many hundreds of miles to the west.

Warner College of Natural Resources Associate Professor of Geosciences Derek Schutt and colleagues have been awarded a $1.1 million National Science Foundation EarthScope grant to explore the Mackenzie Mountains in northwestern Canada, to help address this enigma.

Remarkable mountains

A seismograph site similar to the ones to be installed for the project.

The Mackenzie Mountains, like the Colorado Rocky Mountains, are remarkable in that they formed hundreds of miles away from tectonic plate boundaries where mountain building forces usually occur. While there are multiple hypotheses on these occurrences, there is currently a lack of scientific consensus and data on the creation of these ranges.

“The nearest tectonic plate boundary to the Mackenzie Mountains is 600 miles away,” said Schutt. “This project offers a wonderful opportunity to explore the causes behind an enigmatic mountain range.”

Exploring the Earth’s structure

Schutt will lead the 5-year project with co-principal investigators CSU Geosciences Department Head and Professor Richard Aster and University of Alaska Professor Jeff Freymueller. They aim to use seismology to explore the Earth’s structure to depths of hundreds of miles to identify the transmission of forces uplifting the range and to study the area’s deformation and seismic activity.

The proposed project area. Red dots mark potential seismograph sites.

These data will be collected through the deployment of 40 state of the art autonomous seismographs and 3 continuous, highly accurate, GPS instruments along a nearly 1,000 km transect running through the heart of the mountain range. GPS surveys at 25 additional sites will augment these methods.

Understanding geological processes

Insights from these investigations will provide better understanding of past and present-day geologic processes responsible for valleys, plateaus, mountains, volcanoes, earthquakes and other features in this remarkable part of Canada and mountains around the globe.

With Joel Cubley of Yukon College, the project will engage undergraduate students from Whitehorse in fieldwork, data analysis. These students will be invaluable to the effort due to their local knowledge and experience working in the Territory’s challenging environment. In turn, they will gain valuable experience and insights into geosciences careers and research opportunities.

“We are very much looking forward to collaborating with our Canadian colleagues in learning more about these mysterious mountains, and about how the processes of plate interior mountain building are supported on our planet,” said Aster.

Seismically active area

Additionally, the project will provide much improved study of regions of active faulting throughout the seismically active area. Even without large population centers, knowledge of seismic activity risks is important to protect the regional environment from risks to infrastructure and transportation in the region.

For more information about the project, visit the project’s website.