Recent photos of Joffre Peak show a new crack in the mountain, a sign one geologist says indicates a third landslide could happen at any moment.

Two massive landslides last week sent debris tumbling more than five kilometres down the mountain, about 180 kilometres northeast of Vancouver.

No one was injured.

In aerial photos taken on Saturday, geologist Drew Brayshaw says a crack about 20 to 30 metres long can be seen adjacent to the left of the second slide. This means a slab of unstable rock remains hanging there waiting to fall, he added.

"Whether that means it's gonna slide now, or it might be a week, a month, a year, but it's definitely lost stability," Brayshaw said.

"I think it's more likely than not that there will be another slide there."

Brayshaw, a geologist and environmental consultant in Chilliwack, says the next slide could be as big as the first.

The debris trail from landslides on Joffre Peak as seen from an airplane on Saturday, May 18, 2019. (Gerry Kollmuss)

Avoid the area, geologist says

Alpine permafrost helps to hold rocks in place, but rocks become more susceptible to landslides when it melts, said Brent Ward, co-director for the Centre for Natural Hazards Research at Simon Fraser University.

That melted snow accumulates in fractures in the rock, triggering landslides, he said.

Some research shows the frequency of large slides is increasing due to climate change, Brayshaw said. Landslides like these happen about once a year in the Coastal Range and usually in areas where there are no people, he added.

The two landslides last week at Joffre Peak washed away several backcountry ski routes, like the Twisting Couloir and Central Couloir.

The Cerise Creek trail to Keith's Hut is closed because of damage from the slide and B.C. Parks has also closed the Nlháxten/Cerise Creek Conservancy because of safety concerns.

Joffre Lakes Provincial Park, a popular hiking and walk-in camping spot, wasn't impacted.

Because of the threat of another slide, Brayshaw says anyone interested in hiking or climbing near Joffre Peak should pick another spot for the time being.

"I would certainly be interested in avoiding that area for skiing and climbing, at least, probably, until the rest of the summer," he said.