Taxonomy term

appalachian mountains

Travels in Geology: The geological riches of Quebec's Gaspé Peninsula

A drive around Quebec’s Gaspé Peninsula — bordered by the St. Lawrence River to the north and Chaleur Bay to the south — reveals a rugged coastline dotted with quaint fishing villages, ancient rock formations and an abundance of Devonian-aged fossils that draw amateur and professional geologists alike.
14 Dec 2017

Tectonic rejuvenation in North America's ancient mountains

The mountains of eastern North America, like the Appalachians, Adirondacks and White Mountains, are old: They grew as the pieces of the supercontinent Pangea collided and assembled more than 300 million years ago. It’s been long thought that, after forming — and subsequently undergoing additional uplift and deformation due to rifting during the opening of the Atlantic Ocean — the mountains fell dormant between about 160 million and 200 million years ago. But new work is adding to a growing body of evidence suggesting the ranges were tectonically active well after that.

29 Sep 2016

A real rift in the midcontinent

In the heart of the U.S. Midwest, basalt cliffs and lava flows point to a massive break in the continental crust that occurred a little more than a billion years ago, a feature known as the Midcontinent Rift. Splitting the strong, thick North American craton — the stable interior of the continent — would have required dramatic geologic events. Geologists have long suspected two leading scenarios: a plume of hot mantle rock that sat beneath the several-hundred-kilometer-thick lithosphere, something like the one that sits below Yellowstone today; or mantle material upwelling beneath a zone where the Grenville Orogeny had pulled the rigid continental crust apart as a new supercontinent formed.

30 Jul 2014

Travels in Geology: Thrills and spills at West Virginia's New River Gorge

When Budget Traveler magazine named Fayetteville, W.Va., one of the “Coolest Small Towns in the USA”, it credited not just the town’s young atmosphere and unique shops, but also the local geology, which is nothing short of spectacular.

09 Oct 2008