Photo by Lindy Elkins-Tanton, DTM.
Monserrat's Sougriere Hills Volcano. (Photo by Michael Acierno, DTM)
On the road to Mount Heckla, located on the south of Iceland. [Photo by Michael Acierno, DTM]
"Double O Arch" in one of the countless rock fins of the Entrada Sandstone along the flank of the Salt Valley Anticline in Arches National Park, near Moab, Utah. (Photo by Christian Klimczak, DTM)