Sliding Rocks on Racetrack Playa, Death Valley National Park: First Observation of Rocks in Motion
Image acquired with a handheld digital camera on January 9, 2014. Image on the left shows the wide-angle view; interior black frame indicates the view in other frames. In close-up frames, blue arrows show stationary rocks and red arrow—a rock in motion (moving from left to right). Total movement lasted ∼18 seconds. Dark, flat areas on the pond are panels of ∼3 mm thick ice surrounded by rippled water several centimeters deep. Ice thickness estimated from inshore ice panels. Broken ice panels accumulated on the upstream side of the moving rock in the last two images. Images have been cropped but not otherwise edited.