Coastal landslide caught on film

When a large crack rang through the air, followed by a rumble, Robert and Chris Wills knew to grab their cameras and start shooting. Chris, a geologist, and his son Robert knew they were in for the show of a life time.

As we were admiring the waves, a crack and the ensuing sound of a waterfall of rocks caught our attention. Everyone on the beach spun to see a small stream of rock flowing down the cliff face below the arch. I never could have expected what happened next. Two minutes later, a few chunks of rock fell from the underside of the arch and I started my camera.

Then the arch started to buckle in on itself and squeeze out rock from beneath it. With this, the collapse of the arch shortly followed and the entire surrounding hillside started to slip off into the ocean in a thundering roar. Boulders the size of a piano crashed into the surf and the sand, sending up a large splash of debris that got me a little nervous. It all lasted less than 10 seconds and left the beach quiet in comparison. T he roar of the surf nothing compared to the thunder of the rockslide.

Stunning Marin beach landslide caught on camera (two galleries), SF Chronicle

(Thanks, Joel!)