Bryce Canyon (5 July)
Our trip in the shuttle bus took us to Rainbow point 9115 feet (2778
meters) above sea level. Our driver provided a lot of information as we
climbed, especially about the forest, the species in it, and the place
of fires as a natural phenomenon in forests. He showed us
a tree that had been hit by lightning. A tourist was impaled with hundreds of splinters from the tree. The tourist is no more but the tree survives, despite a big chunk of its bark and some of the wood being blasted.
As we have moved from park to park, brochures and visitor centres have provided information on the geology of each park and how it fits in with the bigger picture. Unfortunately, some of the information, especially about time frames, varies from source to source!
The brief story is that rock and rock material has been building for up to a billion years. There are various layers of different types of rock and that rock has changed through pressure, heat, etc. In addition, earthquakes and volcanoes have shaken it up and twisted it about. Glaciers have had a bit of an effect but more significantly, water has entered cracks in rocks and has frozen overnight at high altitude (and therefore expanded), placing pressure on the rock and widening the crack. It thaws and then more water enters a slightly wider crack and the process repeats. This is the main cause of bits of rock falling away and leaving fins of strangely shaped rock sticking up from the more rapidly eroded softer rock. As the process continues, arches are formed in the fins and some of these then collapse to create hoodoos, the mushroom-like shapes in the pictures below.
What makes this collection of parks so special is that they form a staircase of showing this process over different eras. The bottom of the staircase can be seen in the Grand Canyon where, about six million years ago, the Colorado River began to carve a channel through the rock. It is a mile deep, taking us to the beginning rocks in the process. Bryce Canyon is at the other end, revealing only the top layers which are being eroded to form hoodoos. Arches Park lies somewhere between the two.
As we have moved from park to park, brochures and visitor centres have provided information on the geology of each park and how it fits in with the bigger picture. Unfortunately, some of the information, especially about time frames, varies from source to source!
The brief story is that rock and rock material has been building for up to a billion years. There are various layers of different types of rock and that rock has changed through pressure, heat, etc. In addition, earthquakes and volcanoes have shaken it up and twisted it about. Glaciers have had a bit of an effect but more significantly, water has entered cracks in rocks and has frozen overnight at high altitude (and therefore expanded), placing pressure on the rock and widening the crack. It thaws and then more water enters a slightly wider crack and the process repeats. This is the main cause of bits of rock falling away and leaving fins of strangely shaped rock sticking up from the more rapidly eroded softer rock. As the process continues, arches are formed in the fins and some of these then collapse to create hoodoos, the mushroom-like shapes in the pictures below.
What makes this collection of parks so special is that they form a staircase of showing this process over different eras. The bottom of the staircase can be seen in the Grand Canyon where, about six million years ago, the Colorado River began to carve a channel through the rock. It is a mile deep, taking us to the beginning rocks in the process. Bryce Canyon is at the other end, revealing only the top layers which are being eroded to form hoodoos. Arches Park lies somewhere between the two.
We walked along some of the rim and had some spectacular views. Time to let the pictures do the talking.
Spectacular. Later in the day we rested and watched a chipmunk climb onto the wheel of a motorhome.
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