USGS believes ‘seismic signals’ are linked to landslide in Rocky Mountain National Park

A landslide closed part of Rocky Mountain National Park. The a slide has occurred in Upper Chaos Canyon park area on Tuesday and there is an investigation into what caused it.


Rocky Mountain National Park

The Google Earth photo shows several outcrops on the southern shoulder of Hallett Peak that fell around 4:30 p.m. Tuesday. Rainstorms are forecast for the region through July 3, which could contribute to additional rockfall activity. No one was hurt.

The US Geological Survey says the landslide was “preceded approximately 100 seconds earlier by an M1.5 earthquake-like signal located at or near the surface in the area where the landslide occurred. is produced”.

“There are actually two seismic signals associated with the landslide. The sequence started with what sounds like a very small earthquake, then about 100 seconds later there is a second, more gradual rumble signal that sounds like much more to the type of signal we’re seeing from landslides similar to what was filmed,” USGS’s Kate Allstadt told Golden.

RMNP has closed all areas of Chaos Canyon west of Lake Haiyaha to all users due to rockfall activity and potential impacts. the closure will remain in effect until the forecast thunderstorms pass and the grade can be assessed by National Park Service geologists.

Scientists alternatively say “sudden rockfalls with significant free fall can generate signals that resemble shallow earthquakes”.

“So we think they are related. The earthquake was quite small magnitude, 1.5, so you wouldn’t even feel it if you were just standing on it. So it’s unlikely, but not impossible, that the earthquake triggered the landslide. But what we think is more likely is that the earthquake actually reflects some information about the triggering of this landslide,” Allstadt said.

Additional information from the RMNP:

The hiking trail to Lake Haiyaha, Lake Haiyaha itself, and the hiking trails on the north side of Hallett Peak remain open. The bouldering area in lower Chaos Canyon on the north and east shores of Lake Haiyaha will remain open.

Park visitors who plan to recreate in the rocky areas of the park are reminded to always exercise due diligence and exercise caution. Rocky slopes on and near mountain peaks can be unstable. Recreational users should know their own limitations and choose routes that are within reach of everyone in their group.

For more information about Rocky Mountain National Park, visit or call the park information office at (970) 586-1206.

Virginia F. Goins