Taxonomy term

rockfall

Lidar sheds light on roadside rockfall hazard

Rockfalls represent a significant hazard on many U.S. roadways that wind through steep terrain. But with money tight for roadside hazard mitigation, engineers are looking for more efficient ways to assess where and when unstable slopes could give way. In a new study, researchers suggest that lidar might be a cost-effective solution.

21 Jul 2017

Down to Earth With: Yosemite's first park geologist Greg Stock

As a child growing up in the foothills of California’s Sierra Nevada Mountains, Greg Stock and his family took frequent trips to Yosemite National Park. One of his first memories is of hearing and seeing a giant rockfall tumble down the face of El Capitán. Today, Stock studies such rockfalls and how they impact safety in the area as the first park geologist employed at Yosemite. 
 
09 Feb 2016

Seismometers listen for falling rocks

Scores of natural rockfalls occur in California’s Yosemi­­te Valley every year, often with little or no advance warning, posing hazards to people and infrastructure. In 1980, for example, a fall near Yosemite Falls killed three people and injured 19. Efforts to record and document rockfalls are rudimentary, relying only on eyewitness accounts and after-the-fact observations of fresh talus piles, which means many events are likely going unreported. In a new study, however, researchers interested in whether there’s a better way to monitor these events propose that seismic and infrasound sensors can help keep tabs on the granite slabs dropping from Yosemite’s cliffs.
 
25 Aug 2015

Yosemite's cliffs in retreat

This past winter, two athletes grabbed the world’s attention as they climbed up the sheer walls of Yosemite National Park’s El Capitan. But some geologists are more concerned with what falls down these precipitous faces — namely, rocks. Park geologist Greg Stock has developed a history of rockfalls in Yosemite valley dating back 15,000 years, which reveals how its cliffs have crumbled since glaciers disappeared at the end of the last ice age.

 
11 May 2015

Witnessing geology in action: A rockfall in the garden of the gods

In lieu of doing a "year in review" issue this year, EARTH asked our staff and some frequent contributors to write a short commentary on something that grabbed their attention in 2013. We gave everyone carte blanche. What follows is a collection of extremely varied, often very personal insights into how the planet impacted each individual. In this commentary, EARTH's roving reporter Mary Caperton Morton muses on on how witnessing a rockfall made her think about geologic time.

21 Nov 2013