Tuesday, November 4, 2008


When we saw the top part of this layer we stopped at "The Neck," on the North East end of Canyon Lands National Park we were actually standing on the Glen Canyon Group which is the upper layers of the Triassic. We were standing in the Navajo Sandstone which looks like great rolling sand dunes, because they are petrified sand dunes. From the neck, if you look east, you can see down into a big canyon and see alot of different layers. The first we see is the Navajo Sandstone which is a white cross-bedded layer, underneath that is the Kayenta Formation. According to the Canyon Lands Pamphlet the rangers gave us in the beginning of the park, the Kayenta is formed from meandering rivers, and there are deposits of lime stones and shales in these layers. The Wingate Formation is right underneath and it is evidence of another really dry time, created by rolling sandstones and this layer too will have the cross-bedding we see in the Navajo. These three layers keep the cliffs pretty sheer and straight due to composition although with the Kayenta it is a bit 'stair step' look to it because of it's lesser Resistance to weathering. As we drop down we come to the lower parts of the Triassic Era and the cliffs turn into steep to shallow slopes usually covered mostly with eroded rock and sediment from the higher layers, but here we see the Chinle formation and the Moenkopi. they are layers of shale, clay, sandstone. They are formed under water and swamps. In the Chinle we find a lot of petrified wood. In that layer as well we find a lot of Uranium.
Here we get to the Permian Era about 250 million years ago. It is best seen as you look around the canyon and see where the shallow slope immediately drops off into anther canyon. There is a white layer of rock that runs around the rim and it is made of sandstone. Sandstone is less resistant, so it creates these crevasses. That layer is the top of the Cutler Group called the White Rim Sandstone.

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