Zion National Park 3

(9/27 and 9/28) Geology notes.

In and west of Zion, we saw part of the same cross-section of rock layers we saw at Capitol Reef, with the early Mesozoic Moenkopi formation at the bottom and the mid-Mesozoic Navajo sandstone near the top. The difference is that, at Capitol Reef, the relatively thin Navajo layer was the frosting on the cake. In Zion, the canyon walls rise very high above the valley floor and they are mostly Navajo sandstone--huge monoliths of it.

As we proceeded upriver in the canyon, we rose above the softer underlying layers so that at the end only the Navajo was left. No longer being undercut by erosion of softer sediments, the Navajo was now cut only by the Virgin River itself, and the canyon walls came very close together in a section called the Narrows. The only way to continue upriver would have been to wade in the river itself. We did not, but many others (mostly young people) did.

On 9/28, we decided we were ready to get away from the crowds for a while, so drove to a dry wash and a reservoir west of the park to look for birds. We saw only a few birds, but did recognize some of the same rock layers we had seen at Capitol Reef, and did enjoy having some of the desert to ourselves for a while.

Zion National Park 2

(9/27) In the park and beyond.

The Scenic Drive in Zion follows the Virgin River up the canyon until it is too narrow for vehicles. Private cars are not allowed on the Drive; shuttle buses take visitors to various stops along the canyon road. Our destination today was Riverside Walk, the trail at the end of the road that goes further into the canyon.

It's only a 2-mile round trip but typical to our Gire style it took us until late lunchtime to complete it! There were plants, some flowering, to photograph. . .

. . . birds and squirrels to watch. . .

. . . and more impressive scenery to view. Hanging gardens were in several locations along the trail. Hanging gardens are locations on the sheer rock walls where water seeps through and permits various plants to get a foothold.

For our late afternoon and evening, we followed up on some information given to us about birds. When I ( Judy) asked a ranger about good birding locations in the park, he asked if I wanted to see condors. I said, "Do you ever get a 'no' to that question?"

To get to the condor roost we had to drive outside the park, then up onto several mesas (a total of about 4600' climb). By the time we actually found the roost (missed it the first time around), it was getting dark. But we did see California Condors -- 4 of them roosting in a bare tree. We didn't get to see them fly in but there was no mistake about what the birds were. Hopefully we'll see them in flight over the Grand Canyon.

Zion National Park, Utah 1

(9/26) Arriving at Zion.

The trip from Bryce to Zion is short, only about 90 miles, but the last 15+ are spectacular! Massive Navajo Sandstone cliffs can be seen for quite a distance. After entering the park the 2-lane road narrows to no shoulders and downward twists and turns as it approaches the 1.1-mile long tunnel.

Just before the tunnel is a small parking lot for those who want to hike the 1-mile round trip up to a canyon overlook. We did - the trail brings you up over the tunnel and you're looking down on the switchbacks you will follow after leaving the tunnel! It was a tough trip for me (Judy) with my fear of heights, mid-day heat (high was 97!), and still recovering from a chest cold. But it was worth it!

Our lodging in Zion is just outside the park at Desert Pearl Inn, on the banks of the Virgin River, the stream that cut the canyon. And what a spot it is. Here is our view from the private patio off our room. What a great place to enjoy a glass of wine with the setting sun. Everyone should have this view at the end of a day!

Bryce Canyon National Park 4

(9/24 and 9/25 continued)

We enjoyed Bryce Canyon both from the overlooks at the top . . .

. . . and from a trail down into Fairyland Canyon.

It was one of the most delightful places we have ever experienced.

Bryce Canyon National Park 3

(9/24 and 9/25 continued)

Geologists refer to rock spires of variable thickness such as these at Bryce Canyon, as "hoodoos."

To an early observer their shapes may have suggested the presence of magical powers.

According to Paiute Indian legend, before there were Indians, there were the Legend People. For something bad that the Legend People did, Coyote turned them all into rocks. You can see them now in Bryce Canyon, some standing in rows, some sitting down, some holding onto others.

Bryce Canyon National Park 2

(9/24 and 9/25 continued)

While the rock of the Claron formation was buried by younger sediments and under pressure, it developed a system of perpendicular stress joints. Now that this beautiful pink and white rock is exposed, it erodes along those joints.

Erosion in one direction separates the rocks into fins . . .

. . .then erosion in the perpendicular direction through the fins produces spires, or at least spire-topped fins.

The caprocks on these spires are from the more resistant limestone or sandstone beds and have rather broad tops.

When the caprock erodes off, the less resistant rock below erodes more quickly, and the spires then have more pointed tops.

Bryce Canyon National Park, Utah 1

(9/24 and 9/25)

Once again, we found ourselves on top of a mesa, admiring both the forest on top . . .

. . . and the scenery on the sides. Unlike Canyonlands or Mesa Verde, however, at Bryce we were not looking into steep-sided canyons but rather onto fantastically decorated slopes.

The rock here glows in varying shades of salmon, pink, and white.

This colorful rock, the Claron formation of early Cenozoic age, is the youngest sedimentary rock we have seen or will see on the Colorado Plateau. It lies above the late Mesozoic rock we saw at Mesa Verde, above the early and middle Mesozoic rock we saw at Arches and Capitol Reef and will see again at Zion, and way above the Paleozoic rock we will see at the Grand Canyon.

The Claron formation is special for its colors and for the way it erodes. It is composed of silt, sand and lime carried down to landlocked lakes by rivers from mountains having marine sediments. When lake levels were low, the roots of aquatic plants helped oxidize the iron that was present, contributing the colors. When lake levels were higher, a whiter limestone was deposited, but most of that has been eroded off here. The white bands seen here may be due to deposition during drier periods when the mineral concentration in the water was very high and plants did not grow. After a period of uplift, this rock was exposed by headward erosion of stream beds from a neighboring valley into the sides of the mesa.

Grand Staircase-Escalante National Monument, Utah

(9/23) Today, on the way from Capitol Reef to Bryce Canyon, we crossed this huge (100 by 200 miles) preserve.

Approaching it on Boulder Mountain, we enjoyed our first views of brilliant fall color in the Aspen trees.

The eastern part of the monument is a striking landscape of white Navajo Sandstone hills and canyons, very popular for hiking.

In places the hills had the "Capitol dome" shape we saw in Capitol Reef.

Toward the end of our drive, we crossed an impressive badlands and looked up to have our first sight of the pink cliffs of Bryce Canyon.

Capitol Reef National Park 2

(9/22)  Geology of Capitol Reef

The second day, we followed a west-to-east route across the park with the aid of a book that identified the rock formations The rocks exposed along this route span the Triassic and most of the Jurassic periods -- the age of dinosaurs -- and they exhibit considerable variety. What we learned is that, here at least, the thin-bedded, easily eroded rocks (shales, siltstones, and some sandstones) were deposited in wet environments, while the thick erosion-resistant sandstones were formed in desert conditions by wind blown sand.

The oldest formation we encountered was the Moenkopi, chocolate-brown shaley slopes at the bottom and columns of alternating siltstones and sandstones above. A shallow sea here fluctuated in level, so that sometimes this area was near the shore where the water had considerable movement and at other times this area was farther offshore where there was little or no current. Of the particles carried down to the sea from the mountains, the sand dropped out first, near the shore, while the silt got carried into deeper water and the finest particles (forming shale) were deposited farthest from shore.

Above the Moenkopi is a striking gray-green band of soft claystone, part of the Chinle formation, which was deposited by rivers after the sea had retreated to the west. Other parts of the Chinle continue up to the base of the high cliff, including some thin-bedded sandstone that was deposited by fast-flowing rivers.

The high cliff itself is Wingate Sandstone, formed from quartz sand that was deposited when this area was part of a huge desert.

Here is a closeup of the Kayenta formation, from the early Jurassic, with soft rocks from intermittent stream flows (thin-bedded) sandwiched between hard desert sandstones from dryer periods (thick-bedded).

Above the Kayenta is another massive desert sandstone, the Navajo. The Sahara-like desert that existed in the West at that time was one of the largest ever known. The whitish rock of the Navajo Sandstone tends to weather into rounded forms such as the one in this picture, called Capitol Dome.

Above the Navajo is the reddish Entrada formation, When we saw it in Arches National Park, it was the massive desert sandstone from which the arches were formed. Here the desert sandstone alternates with siltstone layers deposited under tidal-flat conditions, indicating that this area was near the edge of the dune field.

We saw several younger layers as well, some resembling the older layers, but you get the picture. The rocks are beautiful on an esthetic level and part of the beauty is in their variety. We found it satisfying to know the reasons for the variety.

We should mention that we had two cloudless nights here, outside the small town of Torrey, where there is no sky glow from city lights. The B and B where we stayed was on a high ridge with 360-degree views. The Milky Way was clearly visible and there were so many stars that it was hard to make out constellations.

Capitol Reef National Park, Utah 1

(9/21) Our first look at the park

Why do they call this park "Capitol Reef"? Well, it protects a long north-south ridge that was an obstruction to westward traveling pioneers. They referred to any such obstruction as a "reef." A prominent rock formation here often weathers in the form of a white dome reminiscent of the Capitol dome. The ridge itself also has an odd name -- the "Waterpocket Fold." It is a 100-mile long fold in the Colorado Plateau where the normally level rock strata are pushed up on one side exposing a cross-section of rock types. The "waterpockets" are depressions in the sandstone that hold water after a rain. For us, the park provided an opportunity to enjoy beautiful landscapes and learn some geology.

The first day, we drove the Scenic Drive, without knowing much about the rocks we were seeing, and walked sections of two trails. The first trail was along the "Grand Wash," which is dry most of the time, but caries a lot of water after a deluge.

The second walk was along the "Capitol Gorge," a narrow passageway through the rocks that was once a pioneer road.

At lunch, we enjoyed a great ambience . . .

. . . as well as live entertainment (an Antelope Squirrel).

The Mormon settlers who once lived here grew fruit near the river. The park service still maintains the orchards and allows visitors to pick the fruit.

Natural Bridges National Monument, Utah

(9/20)

On the drive from Mesa Verde to Capitol Reef, we drove through much beautiful country, especially near the Colorado River Valley. Because it was a long drive, the only place we stopped for photographs was at Natural Bridges National Monument.

Natural Bridges is in arid canyon country sparsely covered with a stunted pinyon pine-juniper woodland.

The meandering canyon here is a beautiful white sandstone.

Here we learned that natural bridges are different from arches. Arches are formed when rock fins are eroded by rain water as we learned in Arches National Park. Natural bridges are formed when a river following a meandering canyon cuts through a rock wall separating two sides of a meander to create a shortcut. The rock wall remaining above the cut-through is the bridge. At Natural Bridges National Monument, there are three such bridges. This one is called Sipapu. The original course of the river was around the left end of the sunlit rock wall to the left of the bridge.

At the second bridge, Kachina, the river originally flowed around the right end of the rock wall seen here, but cut a channel through the wall and now flows under the resulting bridge.

The course of the river at the third bridge, Owachomo, has an interesting twist, so to speak. The river originally flowed around the left end of a rock wall, but then cut through it. More recently, the river cut another shortcut (without a bridge) to the right, leaving the channel under the bridge high and dry.

These photos don't convey the sizes of the bridges. Sipapu is quite large with a height of 220 feet and a span of 268 feet, while Kachina, about as large, is 210 feet high and spans 204 feet. Owachomo, the smallest, is only 106 feet high but spans 180 feet. Had we more time, we would have hiked down to the bridges. Even viewing them from an overlook, we found them fascinating and beautiful.