8/16/2019 Sentinel Zion Park Landslide

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How a massive rockslide shaped Zion CanyonThe Sentinel, one of Zion National Park’s iconic peaks at 7,157 feet, towers above the canyon floor, but it was once much larger.University of Utah researchers have determined that 4,800 years ago, it shed 10 billion cubic feet of sandstone, a volume 4.4times larger than Utah’s 2013 Bingham Canyon slide at the Kennecott UtahCopper mine. The debris buried the canyon floor in a 2-mile-long swath to anaverage thickness of 310 feet, damming Virgin River and creating a lake thatexisted for 700 years. Computer modeling, right, shows the Sentinel: 1) prior tothe slide; 2) as the mountain of rock descended; and 3) after filling the canyon. Aphotograph of the canyon floor, bottom, shows how the contours of what’s leftof the debris, nearly half of which has been eroded away.

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Zion Lodge Zion Canyon

Elevated valleyfloor

The Sentinel Approximateformer size ofpeak and therockslide area

Sources: University of Utah, Google Earth The Salt Lake Tribune

The Sentinel

Rockslide