Saturday, July 23, 2011

A visit to Craters of the Moon, Idaho

I'm an Idaho girl. Usually when I say this to people not from Idaho, they think of potatoes... and they don't think of volcanoes. Idaho contains the largest, youngest lava field in North America, with features similar to what you'd find in Hawaii. It's fairly close to Yellowstone National Park, and many visitors to the Craters are surprised at the stark beauty that the black rocks can express. Here are a few shot of what you can see (and do!) when visiting Craters of the Moon National Monument and Preserve.


First and foremost, here's a little introduction to the geology of the Craters area. Approximately 65 Ma, the mountain west began experiencing extensive normal faulting throughout the region. We call this the Basin and Range province, where repetitive north-south trending mountain ranges are evenly spaced with valley separating them. As this continued, an area of hot upwelling mantle, or hotspot, began blowtorching its way beneath the North American plate. Roughly 8-10 Ma, the Craters area sat above this Yellowstone hotspot. As the hotspot melted and thinned the underlying lithosphere, it created explosive rhyolite eruptions, similar to the type of volcanics you find at Yellowstone today. As the plate continued to move, the hotspot left the area, and is currently beneath Yellowstone National Park. Because the lithosphere has been thinned, it becomes more difficult to create ranges from Basin and Range normal faulting - the lithosphere just doesn't have enough heartiness to it. Instead, the lithosphere rifts apart, releasing the pressure on the underlying mantle, allowing the mantle to melt to create magma. The magma slowly migrates to the surface along the length of the rift. Approximately every 2,000 years (beginning 15,000 years ago), the Craters will erupt along the propagating rift, and create lava flows, fire fountains, cinder cones, and other basaltic features. The last eruption at the Craters was abut 2,000 years ago... which means... any day now we could see more lavas erupting in the middle of Idaho!

Things to do
Ranger Tours
I was once a National Park Service Park Ranger, so I'd suggest taking a Ranger Tour! The rangers at the Craters will lead you through caves (lava tubes), around the youngest cinder cone in the park (Broken Top), or give you an introduction to the geology, cultural history, and modern history (did you know that the Oregon Trail passes through the park?). There is a very informative visitor's center with cool displays and nice bathrooms. Believe me, the Craters are in the middle of nowhere. You'll be thankful for clean bathrooms.

The Loop Road
Most of the main features are accessible along the park's 7 mile loop road. Off of this road, you can hike to the top of a cinder cone (Inferno Cone), or hike into the mouth of a volcano (North Crater Trail). You can also explore several lava tubes, which are the park's proud caves. The caves stay nice and cool all summer long. In fact, you can find ice in some of them all year round! The caves are by permit only, so be sure to get your permit from the visitor's center before going. 

Wildflower Season
Surprisingly, there is a lot of life out on the cinders and lava. Wildflowers typically start blooming in early June. Different species will bloom at different times throughout the summer, and one flower (the Blazing Star) is only open at night as it's pollenated by moths. Peak time for the wildflower bloom is usually the end of June or beginning of July, depending on how much precipitation has fallen. My favorite is the bitterroot, which is also the state flower of Montana. It grows right out of the cinders, indicating that the lavas are holding water, even though it's hot and dry on the surface.
Winter
The Craters are open year round. At about 6,000 feet elevation, they get their fair amount of snow. In fact, there is so much snow there in the winter that the 7 mile loop road is closed to vehicles, and opened for cross-country skiing! You can also take snowshoes out onto the lava flows. Have you ever summit a cinder cone on snowshoes? It's an amazing experience!

Well, that's my plug for visiting Idaho and visiting a national park. There's also a campground that can accommodate RVs and tents, in case you have so much fun that you decide to stay the night. There are also a lot of special events that happen. For example, the astronomical society brings out their telescopes twice per summer and allow the public to explore the night sky. The views of the Milky Way are absolutely stunning! Here are a few more pictures of the Craters. Hope to see you in Idaho!

In the mouth of North Crater, viewing the Pioneer Mountains
Backside of Inferno Cone, covered with dwarf buckwheat flowers


Dwarf buckwheat in bloom

all photos property of Tiffany A. Rivera

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