In the Petrified Forest National Park of Arizona, while stopped at the car park for the Crystal Forest Trailhead, I spotted this imposing lump of rock on the other side of the road. To me it looks like a dinosaur –obviously one needs a good imagination and the right Sun angle is helpful.  Photographer: Phil Lachman

“Dinosaur Rock” took shape during eons of erosion. The primary element of erosion here is associated with the dramatic summer thunderstorms. Wind and frost wedging also play roles. With little or no vegetation to hold the rock and soil in place any weathered material is easily removed by torrents of water — of course, gravity contributes too. Note the talus cones at the base of Dinosaur Rock — center of photo.

On a drive through Petrified Forest National Park, you will see some of the most colorful and plentiful petrified wood in the world. Should you visit be prepared to see the multihued badlands of the Painted Desert, archaeological sites, native grasslands and displays of over 200-million-year-old fossils.   Photo Phil Lachman