Basin and Range Geology

Basin and Range Geology

If you’re driving to the California Trail Interpretive Center, you’ll notice the same thing the pioneers did more than a century ago: the road goes up and down a series of mountain ranges, all running from north to south. As Maj. Clarence Dutton, one of the [early explorers] colorfully noted, the map of Nevada looks like “an army of caterpillars crawling northward out of Mexico.”  In fact, Nevada is most mountainous state in the country, with 314 named mountain ranges.

Geologists call this kind of topography “Basin and Range.” Today, we know something the pioneers didn’t: how those mountains came to be in the first place.

Unlike the Cascade or Appalachian mountains, which are “compressional,” meaning they are caused by tectonic plates slamming into each other, Nevada’s many ranges are “extensional:” they are caused by the North American plate stretching out over several million years. Have you ever seen someone make pizza? When the cook stretches out the pizza dough, some parts of the dough stay up and some fall down, making ridges. The same thing happened to the Basin and Range province; the difference is that when a tectonic plate stretches out, earthquakes happen. Each mountain range in Nevada was built up by a series of earthquakes, where one side of the opening in the earth, called a “fault,” stayed up and the other side fell down. These faults are the reason Nevada has so many rich mines and hot springs: faults open up cracks in the earth that allow heat and mineral-rich fluids to flow up to the surface.

Now that you know the story of Nevada’s mountain ranges, keep an eye out for your favorite. Here in Elko, we love the Ruby Mountains the best.