Manhattan Schist #1
John Kaprielian
Layered Outcrops On Mars
NASA/JPL-Caltech
Manhattan Schist
John Kaprielian
Moru Kopje, Serengeti
Gregory G. Dimijian, M.D.
Chiricahua National Monument
Mark Newman
Peggys Point Lighthouse, Nova Scotia #1
Theodore Clutter
Iron Oxide Stains
Charlie Ott
Cretaceous Granodiorite Outcrops, Idaho #1
William Mullins
Cretaceous Granodiorite Outcrops, Idaho #2
William Mullins
Cretaceous Granodiorite Outcrops, Idaho
William Mullins
Igneous Outcrop
E.r. Degginger
Grand Canyon West
Mark Newman
Orange Lichens
Ted Kinsman
Cliffs Of Tsingy Limestone, Madagascar
Greg Dimijian
Tsingy Limestone, Madagascar
Greg Dimijian
Granite From The Idaho Batholith
William Mullins
John Day Fossil Beds #1
Tracy Knauer
Crumpled Strata Of Metamorphic Rocks
Gregory G. Dimijian, M.D.
Colorful Sandstone In Arizona
Adam Jones
Joshua Tree National Park
Jeffrey Lepore
Buffalo National River, Arkansas
Bruce Roberts
Red Sandstone Cliff, Utah
Charlie Ott
Coal Seams In A Cliff Face
Charlie Ott
Eroded Red Sandstone, Utah
Charlie Ott
Rock Formation, Utah National Park #1
Photo Researchers, Inc.
Trench Dug By Opportunity On Mars
NASA / JPL-Caltech
Mars Surface From Opportunity
NASA / JPL-Caltech
Opportunity Rover On Mars #4
NASA / JPL-Caltech
Martian Rock #1
NASA / JPL-Caltech / Cornell Univserity
Chiricahua National Monument #1
Mark Newman
Chiricahua National Monument #2
Mark Newman
Point Reyes Historic Lighthouse
Ron Sanford
Rock Formation, Mexico
Art Wolfe
The Devils Tower National Monument
Rafael Macia
Ancient Lake Sediments
William H. Mullins
Balanced Rock, Idaho #1
William H. Mullins
Columnar Basalt In Idaho
William H. Mullins
Red Sandstone
Richard and Ellen Thane
Spider Rock, Canyon De Chelly
George Ranalli
Grand Canyon
Richard and Ellen Thane
John Day Fossil Beds
Tracy Knauer
Racetrack Playa #2
GIPhotostock
John Day Fossil Beds
Jim Corwin
Chiricahua Mountains, Arizona
Gregory G. Dimijian, M.D.
Soit Ngum Kopje, Serengeti
Gregory G. Dimijian, M.D.
Enchanted Rock Exfoliating
Gregory G. Dimijian, M.D.
Metamorphic Rocks
Gregory G. Dimijian, M.D.
Serengeti Kopje
Gregory G. Dimijian, M.D.
Enchanted Rock, Texas #1
Gregory G. Dimijian, M.D.
Checkerboard Mesa, Utah #1
Gregory G. Dimijian, M.D.
Remarkable Rocks #2
Gregory G. Dimijian, M.D.
Volcanic Basalt
Science Source
Natural Jetty Formed By Igneous Rock
G. R. Roberts
Stair Hole, Dorset, England
G. R. Roberts
Balanced Rocks In Arizona
James Steinberg
Devils Tower, Wyoming
ER Degginger
Chugwater Formation, Wyoming
Jean-Louis Klein & Marie-Luce Hubert
Cowboys Chasing Horses
Jean-Louis Klein & Marie-Luce Hubert
Cowboys Chasing Horses #1
Jean-Louis Klein & Marie-Luce Hubert
Balanced Rocks, Chiricahua Nm
James Steinberg
Rocks At Hermanus, South Africa
Gerard Lacz
Badlands, Theodore Roosevelt Np
Willard Clay
Granite Sea Stack, Malaysia
Fletcher & Baylis
Erosion, Spitzbergen
M. Watson
Folded Rock With Anticline
Dan Guravich
Tree On A Rock
Richard Hansen
Saudi Arabian Desert #3
Ray Ellis
Granite Layer
Karl H. Switak
Peggys Point Lighthouse, Nova Scotia
Theodore Clutter
Volcanic Dike In Granite
A.b. Joyce
Pancake Rocks, New Zealand
A.b. Joyce