Trees along the Washington coast were killed by salt-water invasion when the land suddenly dropped during the last great Cascadia Subduction Zone earthquake in the year 1700.
Point Reyes National Seashore, California. An offset fence line reveals the 16 feet (5 meters) of lateral ground breakage that occured as the San Andreas Fault suddenly let loose during the 1906 San Francisco Earthquake.
The valley of ten thousand smokes. Public domain photograph of Alaska volcanic mountains, free to use, no copyright restrictions image - Picryl description
The beautiful beaches of the East Coast are part of a passive continental margin formed as the Atlantic Ocean opened and the edge of North America subsided and was covered by thick layers of sand and mud.
Earth’s outer shell is broken into tectonic plates that move relative to one another. The plates rip apart at divergent plate boundaries, crash together at convergent plate boundaries, and slide past each other More
The edge of the Gulf of Mexico is a passive continental margin formed as South America and the Yucatan Peninsula ripped away from North America, forming beautiful beaches and barrier islands.
Lava Beds National Monument, California. Tule Lake basin is partially filled with sediments and lava flows.
Lanfair Valley (basin) Public domain photograph of mountain range, free to use, no copyright restrictions image - Picryl description
Active subduction along the southern Alaska coast has formed a volcanic arc with features including the Katmai caldera and neighboring Mount Griggs. Katmai National Park and Preserve, Alaska.
hikers on hill slope with valley and hills in background The explosive volcanic activity that formed the giant crater (“caldera”) is due to silica-rich (granitic) magma formed as hot asthenosphere rises and mel More
Badwater Basin in Death Valley National Park is the lowest point in North America, 282 feet below sea level. The valley and surrounding mountain ranges are on the western edge of the Basin and Range Province.
Jennifer Natoli was a seasonal ranger at Redwood National and State Parks in California. In her version of the Oreo® cookie demonstration, the creamy filling is the layers of sediment and basalt on the ocean fl More
Fountain eruption during the 1959 eruption of Kilauea Iki. Public domain photograph of a volcano, eruption, volcanic smoke, ashes, lava, free to use, no copyright restrictions image - Picryl description
View through a collapsed roof (skylight) of red-hot lava flowing through a lava tube during 1969–1974 eruption of Mauna Ulu.
Pu'u O'o is a cinder cone formed by a fountain eruption during the ongoing activity on Kilauea Volcano that began in 1983.
A Continental Hotspot in the Yellowstone area results in many volcanic and geothermal features, including this hot spring pool. Crested Pool, Upper Geyser Basin.
Heart Spring Public domain photograph by National Parks Administration, nature conservation, tourism, free to use, no copyright restrictions image - Picryl description
Mammoth Hot Springs—Mammoth Hot Springs form in the northern part of the park where the hot water flows through limestone. Dissolved calcium carbonate is deposited on the surface as beautiful terraces.
Mammoth Hot Springs Terrace Public domain photograph by National Parks Administration, nature conservation, tourism, free to use, no copyright restrictions image - Picryl description
Sawmill Geyser Public domain photograph by National Parks Administration, nature conservation, tourism, free to use, no copyright restrictions image - Picryl description
Fishing Cone Spring. Hot Springs develop where the geothermal waters flow freely to the surface.
Old Faithful geyser. Geysers form where dissolved silica from rhyolite volcanic rocks constricts flow. Under pressure, the superheated water flashes from liquid to gas, propelling the column of water upward thr More
Available also through the Library of Congress Web site as a raster image.
Gates of the Arctic National Park and Preserve, Alaska. NPS sites in northern Alaska are vast wilderness areas that lie in the Brooks Range, a collisional mountain range that is younger and higher than the Appa More
A grocery store checkout counter can be used to demonstrate the gradual growth of a continent via terrane accretion. The conveyer belt represents the oceanic plate subducting beneath the continental plate. The More
The rock layers are lifting out of the sea as the Pacific Plate subducts beneath southern Alaska.
Hawaii Volcanoes National Park, Hawaii. The Hawaiian Islands form due to volcanic activity as the Pacific Plate rides over a hotspot rising from deep within the Earth's mantle.
The dark-colored lava flows formed over a billion years ago in the Keweenawan Rift, as the ancient North American continent tried to rip apart and low-silica (basaltic) magma poured out on the surface.
The layering in the upper part of the canyon formed over 200 million years ago, when the Colorado Plateau region was part of an ancient passive continental margin.
Divergent plate boundary Picryl description: Public domain photograph of National Park, nature, free to use, no copyright restrictions image.
Glacier Bay National Park and Preserve, Alaska
The Coastal Ranges are forming as material from the ocean is scraped off the top of the subducting Juan de Fuca Plate.
Nicole Bader, GIP intern explaining plate tectonics at Glacier National Park, Montana.
Denali National Park, Alaska. Denali (also formerly known as Mt. McKinley) and other high peaks in the Alaska Range are built on crust that thickened as terranes came crashing in from the south.
Scientists have found evidence of plate tectonics on Jupiter moon Europa. This conceptual illustration of the subduction process. NASA/Noah Kroese, I.NK
Sunny beach, Canaveral National Seashore, 2015.
The Hawaiian hotspot continues to build the Hawaiian island chain. Eruption of Halema‘uma‘u in 2015.
Volcanic activity above the Hawaii Hotspot continues to build the chain of islands. A steam plume from lava flowing into the ocean can be seen in the distance.
A river flows through a canyon in iceland / A river runs through a canyon public domain stock photo.
Basalt lava field and shoreline. Active flow of molten lava is entering the ocean in the distance causing a large plume of steam.
Sunset Crater Volcano National Monument, Arizona. Another prominent cinder cone, Sunset Crater Volcano, forms where volcanic activity associated with the Basin and Range Province is encroaching on the western e More
Pahoehoe lava has a smooth, ropey surface, formed when the lava is very hot and free-flowing. Hawaii Volcanoes National Park.
The Samoan Islands consist of interlocking shield volcanoes with basalt lava flows, cinder cones, and collapse calderas.
Mt. St. Elias is the second-highest peak in the United States. It consists of metamorphosed sedimentary and volcanic rocks of the Chugach Terrane.
A vertical dike was once magma that cooled and hardened on the flanks of Haleakala Volcano.
The San Andreas Fault is just one of many active earthquake faults in a broad zone of shearing along the transform plate boundary in the San Francisco Bay Area.
Crater Lake in Crater Lake National Park partially fills the large depression formed when a composite volcano erupted and collapsed in on itself 7,700 years ago.
As the mid-ocean ridge separating the Farallon and Pacific Plates entered the subduction zone, the Farallon Plate separated into the Juan de Fuca and Cocos Plates. A transform plate boundary developed where the More
500 Million Years Ago—Iapetus Ocean Opens. Land that will later become Florida is part of Africa. The Yucatan Peninsula and Cuba may have been on the north side of South America.
Golden Gate National Recreation Area, California. Long ridges and valleys around San Francisco Bay are in the zone of shearing along the transform plate boundary.
Where tectonic plates converge, the one with thin oceanic crust subducts beneath the one capped by thick continental crust. A subduction zone consists of material scraped off the ocean floor near the coast (acc More
The light-colored granite rocks are the cooled remnants of magma chambers that fed ancient volcanoes when the subduction zone extended through California and into Mexico.
250 Million Years Ago—Iapetus Ocean Closes. Pangea forms as the continents collide. The Appalachians are part of a larger zone of continental collision that includes the Marathon and Ouachita mountains in the s More
One of the many outstanding murals at the Thomas Condon Visitor Center at John Day Fossil Beds National Monument depicts ancient life on the Columbia Plateau landscape. Note the columnar basalt columns in the foreground.
Most earthquakes and volcanoes occur where the moving plates interact along their boundaries, and at hotspots.
As fluid basalt lava flows into the ocean it forms a pile of globular structures known as pillows.
Haleakala National Park Aa lava has sharp, angular blocks that develop when the lava is cooler and more sluggish.
Katmai National Park Public domain photograph by National Parks Administration, nature conservation, tourism, free to use, no copyright restrictions image - Picryl description
As the plate stretches and thins, the underlying asthenosphere flows upward and expands like a hot-air balloon, lifting the region to higher elevations. The continental crust breaks along faults, forming long m More
Sedimentary layers of the ancient passive margin. As the Colorado Plateau rose upward, rivers carved downward, exposing those layers on the walls of canyons.
The topography and bathymetry (underwater topography) of the northern Pacific Ocean reflect the movement of the Pacific Plate over the Hawaiian Hotspot. Prior to 42 million years ago, the Pacific Plate was movi More
The pinnacles are the eroded remnants of hardened volcanic breccia—slurries of mud and rock from explosive eruptions.
Redwood National and State Parks, California. Visitors to Olympic National Park, Oregon Caves National Monument, or Redwood National and State Parks can look down and imagine the top of the Juan de Fuca Plate a More
Shenandoah National Park, Virginia. The rugged Appalachian Mountains are the eroded remnants of much higher mountains that formed as continents collided 300 million years ago.
Lava Beds National Monument, California. The top of Sconchin Butte, a cinder cone, is a popular hiking destination along the main road through Lava Beds National Monument.
Shaded relief map of United States, highlighting National Park Service sites in Colisional Mountain Ranges. Letters are abbreviations for parks.
Grand Teton National Park, Wyoming. The east side of the Teton Range is a steep fault escarpment rising from the adjacent basin (Jackson Hole).
The Marathon Mountains are the westernmost part of the ancient collisional mountain range that extends, in pieces, from the Maritime Provinces of Canada to west Texas.
The Colorado River has eroded through Paleozoic passive continental margin strata and older rocks, forming the Grand Canyon.
Oceanic islands and continental fragments approaching the subduction zone are too thick and buoyant to subduct. Instead, they attach to the edge of the continent as accreted terranes.
Badlands area in Petrified Forest National Park. The Amazon-like landscape has evolved over more that 200 million years from a green tropical forest to red Painted Desert. Layers of the Late Triassic Chinle For More
The landscapes of National Park System sites along hotspot tracks differ depending on if the plate riding over the hotspot is capped by thin oceanic or thick continental crust. Oceanic Hotspots: Sites in Hawaii More
shaded, raised relief map of north america Shaded relief map of United States, highlighting National Park Service sites along modern and ancient passive continental margins. Letters are abbreviations for parks.
Dry Tortugas National Park, Florida. The beaches of Dry Tortugas at the western end of the Florida Keys are fragments of shells broken up by wave action, and coral reefs developed in the shallow, warm waters.
Petrified logs along the Blue Mesa Trail. As the Colorado Plateau lifted upward, younger sedimentary layers eroded away, exposing the Chinle Formation, along with its colorful badlands, petrified logs, and othe More
Blocks of thick continental crust fit together nicely along the edges of their shelves to form the supercontinent called Pangea.
Kilauea Volcano in Hawaii Volcanoes National Park has a large caldera on its summit. Smaller collapse craters are found on the floor and flanks of the caldera, including Halemaumau and Kilauea Iki. The Volcano More
So much magma erupted that the upper part of the mountain collapsed into the void, forming the caldera. Paul Rockwood painting, NPS.
The sandstone, shale and chert layers are part of a thick pile of sediments that were deformed and uplifted as Gondwanaland collided with the southern edge of ancient North America 280 million years ago.
750 Million Years Ago—Old Continent Rips Apart. The long mountain ranges and rift valleys were similar to those forming today in East Africa and the Basin and Range Province.
A hotspot is like the hot wax rising in a lava lamp. When the lamp is off, the cold wax is more dense than the oil. When you turn the lamp on the heated wax rises because it expands and becomes less dense than More
Crater Lake National Park, Oregon. Crater Lake lies inside a caldera formed as Mt. Mazama violently exploded and collapsed 7,700 years ago.
Plate convergence that built Alaska outward as a series of accreted terranes during the past 200 million years continues today. Kenai Fjords has oceanic sedimentary layers that have been metamorphosed, uplifted More
200 Million Years Ago—Ocean separating northern Alaska and a continental fragment begins to close.
Grooves on the basalt lava flow rocks in Keweenaw National Historical Park reveal the north-to-south direction that ice flowed across the region during the last ice age.
The upper portion of the canyon reveals continental shelf and coastal plain sedimentary layers of the ancient passive continental margin.
Geysers, hot springs and other geothermal features in Yellowstone National Park (right) are reminders that the supervolcano that lies directly above the hotspot is still very much alive.
The Columbia Plateau and Steens Basalt are the initial surfacing of the giant plume head.
"Today"—Atlantic Ocean and Gulf of Mexico Open. The modern oceans originated about 200 million years ago when Europe, Africa and South America ripped away from North America. Fragments of the collision zone mou More
If divergence continues, the continental crust completely breaks apart and thinner oceanic crust forms between the two continental blocks. The ocean basin sinks below sea level because the crust is thinner and More
The idea of continental drift, inspired by the observation that the continents fit together like picies of a giant jigsaw puzzle, provided strong evidence for the theory that later developed as plate tectonics. More