Racetrack Rocks Mystery Solved
No this isn’t school work or us pretending to be smart but it is us broadening our horizons and in an effort to do so we’ll be bringing you our favourite science story every Saturday! Where better to kick this off than with a mystery unravelled – the Racetrack Rocks.
Over sixty years ago scientists discovered strange tracks in the muddy bed of the Racetrack Playa found in California’s Death Valley – the tracks were made by stones but the scientists couldn’t figure out how the stones were moving along the dry lake bed. Everything from high winds, water and ice had been proposed but debunked many agreed though that a combination of wind and water had to factor but the mystery remained. That is until now!
A team of scientists led by geologist Richard Norris outfitted fifteen rocks with GPS to track movement (if any), set up a weather station and time-lapse cameras to capture the rocks during heavy periods of rain and snow. As luck would have it the team were present when they made their breakthrough, following a period of weather (rain > snow > sub zero temperatures), sixty stones had moved and enough data had been gathered to explain how.
The stones moved on a bright day, the heat caused a thin sheet of ice to break apart, these ice fragments clung to the rocks, increasing their surface area on their upwind side, coupled with the wind and the water pushing against them, the stones moved forward.
The teams findings have been published in PLOS ONE, geologist, Paula Messina, who was not involved with the project spoke about the work, highlighting that “…that technology has reached a point where we can solve the mystery of the Racetrack rocks. That’s something scientists couldn’t have done even a few years ago.”
In the video below, Norris explains the study and his report in more detail:
Editor-in-Chief, part-time super villain and hoarder of cats. If you can’t find me writing, I’m probably in the kitchen!
