Monday, June 10, 2013

What Is Your Favorite Volcanic National Park?

So many great choices! Would it be Rainier? Crater Lake? Lassen? Hawaiian Volcanoes? Haleakela? Yellowstone? Zion?

Wait a minute...Zion? Since when does Zion National Park have volcanoes? Since about 125,000 to 1.4 million years ago, actually. The western edge of Zion includes the Hurricane fault zone and a series of associated basalt flows and cinder cones. Firepit Knoll (above) and Spendlove Knoll (below) are two nearly symmetrical cones dating to around 220,000-310,000 years ago.

The park also has an outstanding example of an inverted stream. A flow filled North Creek and erosion removed the surrounding softer rock, leaving the former stream bottom as a prominent ridge.

It's a bit tricky to see, but cliffs drop off both sides of the road, which was built on the surface of the basalt flow. From higher up, the ridge is more obvious (below). The flow emanated from the Firepit/Spendlove Cones.

Where are these features, and how do they get missed by 95% of the park visitors? They can be viewed by following Kolob Terrace Road to Lava Point. The park brochure mentions the road, but I guess there are so many exciting things to see down in the canyon that folks don't set aside enough time to explore this road into the high country. It's both a shame and a blessing.

A blessing because I don't like crowds, but a shame because people are missing out on a very scenic and geologically interesting road. The road climbs 4,000 feet in 21 miles from the village of Virgin to Lava Point, one of the highest points in the national park. On the day we were there last week, the temperature dropped from 104 degrees in the valley to 78 degrees at the lookout. Aspen trees lined the last mile of the drive (most of the road is paved, except for this last bit, but the road is smooth).

The road begins in the Triassic Moenkopi Formation, and quickly ascends the lava flows to exposures of the Jurassic-aged Navajo Sandstone. This is the same unit that forms the spectacular cliffs of Zion Canyon. Without the vertical canyon walls, the Navajo weathers into a bewildering variety of beehives, castles, spires, domes, and whatever else your imagination conjures up.

The road crosses the park boundary several times, and passes through beautiful park-like meadows.

At road's end, we discover why the spot is called Lava Point. Columnar basalts form a cap on the edge of the plateau. At nearly 8,000 feet, the area is covered in a fir and aspen forest.

In a meadow near Blue Springs Reservoir, I caught a horse hanging out with a little friend catching flies on his back.
The cacti were in bloom here and there.
And then there is the view! From this vantage point, we can look into the deep canyons of Zion, and beyond to the Kaibab Plateau and the Grand Staircase. The view also extends to the high plateau country to the north.

There is a small campground set a few hundred yards from the edge of the plateau. There were a few people camping there, and all of six other cars at the viewpoint. It was cool, shady, quiet, and beautiful; a distinct contrast to the normal tourist haunts in Zion Canyon.
Give it a try next time you are in the region. And don't forget the Kolob Fingers, the other outlying, lesser-known part of Zion National Park.


Bill T said...

"Fav volcanic nat'l park?", how about Death Valley? Would the list of National parks with no volcanic history be shorter than the list of those with?

Lyle said...

In the Kolob Canyons section is the highest point in the park:Horse Ranch Meadows at 8726 feet. Looking at it from the end of the road, it has a lava flow on top as well. lieing on Cretaceous rocks some of which are of Dakota age according to the ranger.
Actually driving along i-15 to the south one can see lots of evidences of volcanism, both in lava caps of the cliffs, as well as cascades of eroded lava further down the cliffs.

Garry Hayes said...

In my mind, I always somehow separate the Kolob Fingers and the main part of Zion as two distinctive areas, so I tend to forget how much higher the Fingers are (but I don't forget how dramatic the cliffs are!). Thanks for the info.