Tilted layers showing bedding planes in strata of sedimentary rock in coastal cliff at Odeceixe, Algarve, Portugal, Europe

Petrified sand dunes, White Canyon State Park, Red Cliffs Desert Reserve near St. George, Utah, United States of America

Petrified sand dunes, White Canyon State Park, Red Cliffs Desert Reserve near St. George, Utah, United States of America

Ephemeral Spring on Red Wall of Roaring Springs Canyon, North Kaibab Trail, Grand Canyon North Rim, UNESCO, Arizona, United States of America

The interior of the Supai Tunnel along the North Kaibab Trail, Grand Canyon North Rim, UNESCO, Arizona, United States of America

A canyon that drains into Dead Wash, Petrified Forest National Park, Arizona, United States of America

Aerial of the Trou du Natron volcanic crater and its natron lakes, Tibesti Mountains, Chad

Aerial of the Trou du Natron volcanic crater and its natron lakes, Tibesti Mountains, Chad

Aerial of the Trou du Natron volcanic crater and its natron lakes, Tibesti Mountains, Chad

Aerial of the Trou du Natron volcanic crater and its natron lakes, Tibesti Mountains, Chad

Aerial of the Trou du Natron volcanic crater and its natron lakes, Tibesti Mountains, Chad

Aerial of the rocky mountains around Zouar, Tibesti Mountains, Chad

Continental drift between North American and Eurasian tectonic plates, Thingvellir National Park, UNESCO, in winter, Western Region, Iceland

Continental drift between North American and Eurasian tectonic plates, Thingvellir National Park, UNESCO, in winter, Western Region, Iceland

Continental drift between North American and Eurasian tectonic plates, Thingvellir National Park, UNESCO, in winter, Western Region, Iceland

People and continental drift of North American and Eurasian tectonic plates, Thingvellir National Park in winter, UNESCO, Western Region, Iceland

Boulder pile in a valley leading to Dead Wash, Petrified Forest National Park, Arizona, United States of America

Petrified forest, Agia Marina, Agios Nikolaos Geopark geological structures, Greece

White saxaul (Haloxylon persicum), Sharaan Nature Reserve, AlUla, Medina Province, Saudi Arabia

Glacial iceberg detail from ice calved off the Sawyer Glacier in Tracy Arm, Southeast Alaska, United States of America

Sandstone rock formations in the desert canyons of the Ashar Valley, Medina Province, Saudi Arabia

Sandstone rock formations in the desert canyons of the Ashar Valley, Medina Province, Saudi Arabia

Remarkable sandstone rock carved by erosion in the Ashar Valley, AlUla, Medina Province, Saudi Arabia

Olympus Mons, Mars

Les Terres Noires de Robine sur Galabre under the snow. Jurassic (Toarcian) marls rich in organic matter, tender and very sensitive to gullying, colonized mainly by Scots pines and forming remarkable reliefs in the Digne Geological Reserve, Alpes de Haute Provence, France.

Les Terres Noires de Robine sur Galabre under the snow. Jurassic (Toarcian) marls rich in organic matter, tender and very sensitive to gullying, colonized mainly by Scots pines and forming remarkable reliefs in the Digne Geological Reserve, Alpes de Haute Provence, France.

Les Terres Noires de Robine sur Galabre under the snow. Jurassic (Toarcian) marls rich in organic matter, tender and very sensitive to gullying, colonized mainly by Scots pines and forming remarkable reliefs in the Digne Geological Reserve, Alpes de Haute Provence, France.