Moqui Marbles and Martian Blueberries

May 19, 2013

Moqui Marble Madness

Photographer: Bret Webster; Bret’s Web siteBret’s Facebook page 
Summary Author: Bret Webster 

May 2013 Viewer's Choice The photo above shows Moqui Marbles in their native habitat of southern Utah. These curious rocks are actually concretions having iron (hematite) rinds. Very similar rocks, called blueberries, have been observed repeatedly on Mars by the rovers. Click here to see an image taken by the Opportunity rover of the blueberries. Some scientific papers implicate the possibility of life on Mars playing a role in their formation while others do not. Discussions about the pros and cons of their formation have been quite lively at times. However, the consensus seems to be that both the marbles and the blueberries were created beneath the surface as naturally occurring substances, most likely minerals, precipitated from flowing groundwater. Pictured with the marbles is a Devil's-Claw cactus (Sclerocactus parviflorus).

Photo details: Camera Model: Canon EOS 5D Mark II; Lens: EF24-105mm f/4L IS USM; Focal Length: 24mm;
Focus Distance: 0.64m; Aperture: f/8.0; Exposure Time: 0.0013 s (1/800); ISO equiv: 200; Software: Adobe Photoshop CS5.1 Windows.