Above: Google Earth image of Red Mountain north of the small town of Ivins. A massive prehistoric landslide is outlined with a white line.
Geologists and other observant local have known about this feature for years and naturally many wonder: Is another catastrophic landslide possible off of the flank of Red Mountain?
To get a better idea, a small group of geologists were led up to the top of the mountain to take a closer look.
The "trail" to the top is nothing more than a cairned scramble straight up the prehistoric landslide. I'm not kidding when I say straight up, we're talking about 1400 vertical feet in just 1/2 mile.
The views of the surrounding desert from on top are endless.
Above: geologist Marc Deshowitz observes the western extension of Red Mountain rising above the Kayenta subdivision.
It was a great day to get out of the office, stretch the legs a bit,and look at some rocks, but we couldn't find any evidence for eminent failure. It appears large landslides don't happen too often off of Red Mountain, and if I lived in the area, I wouldn't lose too much sleep over it (smaller rock falls tumbling down the mountain are certainly more likely).
Beautiful pictures. I was in the area recently, except across the valley looking at Red Mountain from the petroglyphs along the Santa Clara River
ReplyDeleteThanks. I love those petroglyphs. There are supposed to be some dinosaur tracks there amongst the rock art somewhere. If I can find them, I'll write about them here.
ReplyDeleteActually, the geologists found evidence of past movement on the west side of Red Mountain with one down to the west fault showing clearly at least 40 feet of vertical offset confirming the aerial observation of a down to the west fault on the western flank of Red Mountain.
ReplyDeleteThe west side of Red Mountain is considered by the Utah Geological Survey to be a low risk/moderate liklihood area. Low risk because there would be minimal loss of life or property if an event were to occur and moderate likelihood if the right conditions like a lot of rainfall couple with a mild earthquake. That is how they assess GeoHazard risks.
The potential of one life lost is a high enough risk for me to stay away from building anything on the west side of Red Mt. near the base of slope.
Correction to my previous post . . . the Utah Geological Survey assessed Landslide risk on the west side of Red Mountain as Low Likelihood and Low Risk. Rock falls were assessed as Moderate Likelihood and low risk. Sorry for my error on the previous post.
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