This panorama was photographed on February 1, 2009 and is available in the project. The following is a transcript of the narration for this panorama. To listen to the narration, enter the project at this location and press the play button.
We have now reached the half way point of the South Kaibab Trail, about 3 1/2 miles each from the trailhead and Phantom Ranch. There’s a sign just a few yards away from this spot that let’s you know.
We are also about halfway down through the big descent through the Redwall Limestone and the Muav Limestone. Looking up the trail, we can see just how far down we have come. Notice all the little retaining walls that the trail builders created for us to smooth out the bumps in the trail – they help make the South Kaibab Trail the hiker’s superhighway that it is.
Looking down the trail , we can see that we still have plenty more switchbacks ahead of us, but there aren’t any more hiding around the corner. We will reach the base of the Muav Limestone and the end of the switchbacks, right here where we see the trail disappearing around the corner.
We are standing on a small platform that makes for a nice rest spot, particularly on a relatively cool day like this in February, but just what rock formation are we standing on? Its hard, pitted appearance says that it is probably limestone, but that doesn’t help much, since we know that we are somewhere between the Redwall and the Muav, both of which are limestone.
I’m an amateur geologist in the true sense of the word – I love it, but I’m definitely no expert. And I usually do have trouble telling the Redwall and the Muav apart – to my eye they blur together into just one big massive cliff that makes me huff and puff when passing through it, whatever trail I’m on. And there’s a further complication – there’s a third kind of limestone, the Temple Butte, that sneaks in between the Redwall and the Muav here and there.
There’s a big time gap, which geologists call an unconformity, of over a hundred million years between the creation of the Redwall and Muav Limestones. One ancient sea laid down the Muav about 500 million years ago. Then that sea retreated and part of the Muav eroded away, until another sea invaded the area 340 million years ago and began to deposit the Redwall. But during part of that time gap, a third sea just reached into this area of a while, and this area was near its shoreline. So here and there that third sea laid down bits of Temple Butte Limestone, and several references I have read say that the South Kaibab Trail passes though one of those bits, so there’s got to be some Temple Butte around here somewhere.
Well I love puzzles, and we do have a couple of clues. Here’s a portion of a geological map from the United States Geological Service mapping geological formations in this area. I’ve placed an orange dot where I think our current position is, but given the fairly small scale of the map it’s hard to tell. Light purple is the Redwall, to the right of it the beige area is the Muav, and in between them you can see a curving e-coli bacteria shape of darker purple, which my dot sits right on top of, which is the Temple Butte Limestone.
So just where in our panorama is it? Here’s the second clue. This is a picture from the USGS web site that is labelled as Temple Butte cliffs along the South Kaibab Trail. And voila! We can see that the photographer shot that picture in just about the same exact spot where we stand. So we can be confident that we are seeing the Temple Butte here as we look off to the southwest. But that e-coli shape on the USGS map shows the Temple Butte continuing off to the northeast and curving around the corner. So judging by the color and character of the rock, this is my best guess of where we see the Temple Butte going off in that direction. And by following the boundary line right through our spot, I conclude that this little platform we are standing on is the very top of the Temple Butte.
Heading up the trail from here, we zig-zag up the switchbacks to a panorama spot at the top of the Redwall cliffs, with a beautiful view down the entire set of switchbacks. Going down the trail, we complete the descent down the switchbacks to another rock boundary, right at the true beginning of the desert.