EARTH GEOLOGY EARTHQUAKES VOLCANOES SINKHOLES & LAND SUBSIDENCE LANDSLIDES & MASS MOVEMENTS WEATHER PHENOMENA OCEAN & COASTAL PHENOMENA NATURAL PHENOMENA HUMAN IMPACTS ON EARTH SYSTEMS SINKHOLES & LAND SUBSIDENCE LANDSLIDES & MASS MOVEMENTS WEATHER PHENOMENA OCEAN & COASTAL PHENOMENA NATURAL PHENOMENA HUMAN IMPACTS ON EARTH SYSTEMS STRANGE SOUNDS MYSTERY BOOMS THE HUM SKY TRUMPETS SPACE SOUNDS OCEAN SOUNDS ANIMAL SOUNDS SONIC WONDERS BROADCASTS SKY STRANGE CLOUDS STORM STRUCTURE ATMOSPHERIC OPTICS AURORAS & PLASMA PHENOMENA MYSTERIOUS OBJECTS & LIGHTS MAN-MADE SKY PHENOMENA STORM STRUCTURE ATMOSPHERIC OPTICS AURORAS & PLASMA PHENOMENA MYSTERIOUS OBJECTS & LIGHTS MAN-MADE SKY PHENOMENA SPACE ASTRONOMICAL EVENTS SOLAR & SPACE WEATHER PLANETARY GEOLOGY & IMPACTS ALIEN LIFE & HABITABILITY SOLAR SYSTEM MYSTERIES COSMIC MYSTERIES SPACE EXPLORATION & OBSERVATION ASTRONOMICAL EVENTS SOLAR & SPACE WEATHER PLANETARY GEOLOGY & IMPACTS ALIEN LIFE & HABITABILITY SOLAR SYSTEM MYSTERIES COSMIC MYSTERIES SPACE EXPLORATION & OBSERVATION ANIMALS & NATURE ANIMAL ANOMALIES & MASS DIE-OFFS PREHISTORIC EARTH LIVING EARTH ODDITIES MASS DIE-OFFS ANIMAL ANOMALIES & MASS DIE-OFFS PREHISTORIC EARTH LIVING EARTH ODDITIES CONTACT // REPORT EARTH GEOLOGY EARTHQUAKES VOLCANOES SINKHOLES & LAND SUBSIDENCE LANDSLIDES & MASS MOVEMENTS WEATHER PHENOMENA OCEAN & COASTAL PHENOMENA NATURAL PHENOMENA HUMAN IMPACTS ON EARTH SYSTEMS SINKHOLES & LAND SUBSIDENCE LANDSLIDES & MASS MOVEMENTS WEATHER PHENOMENA OCEAN & COASTAL PHENOMENA NATURAL PHENOMENA HUMAN IMPACTS ON EARTH SYSTEMS STRANGE SOUNDS MYSTERY BOOMS THE HUM SKY TRUMPETS SPACE SOUNDS OCEAN SOUNDS ANIMAL SOUNDS SONIC WONDERS BROADCASTS SKY STRANGE CLOUDS STORM STRUCTURE ATMOSPHERIC OPTICS AURORAS & PLASMA PHENOMENA MYSTERIOUS OBJECTS & LIGHTS MAN-MADE SKY PHENOMENA STORM STRUCTURE ATMOSPHERIC OPTICS AURORAS & PLASMA PHENOMENA MYSTERIOUS OBJECTS & LIGHTS MAN-MADE SKY PHENOMENA SPACE ASTRONOMICAL EVENTS SOLAR & SPACE WEATHER PLANETARY GEOLOGY & IMPACTS ALIEN LIFE & HABITABILITY SOLAR SYSTEM MYSTERIES COSMIC MYSTERIES SPACE EXPLORATION & OBSERVATION ASTRONOMICAL EVENTS SOLAR & SPACE WEATHER PLANETARY GEOLOGY & IMPACTS ALIEN LIFE & HABITABILITY SOLAR SYSTEM MYSTERIES COSMIC MYSTERIES SPACE EXPLORATION & OBSERVATION ANIMALS & NATURE ANIMAL ANOMALIES & MASS DIE-OFFS PREHISTORIC EARTH LIVING EARTH ODDITIES MASS DIE-OFFS ANIMAL ANOMALIES & MASS DIE-OFFS PREHISTORIC EARTH LIVING EARTH ODDITIES Geology: Key Facts Earth is powered from within. Internal heat drives mantle convection, volcanism, crustal deformation and plate tectonics. Landscapes are temporary. Mountains, canyons, arches, cliffs and coastlines continuously change through uplift, weathering and erosion. The seafloor is a dynamic geological landscape of ridges, trenches, seamounts, fracture zones and sedimentary basins. Earth’s magnetic field changes. Magnetic poles drift, field strength varies and polarity has reversed many times. Continents move and reorganize. They split apart, collide, subside and assemble into supercontinents. What Is Geology? Geology is the science of Earth’s materials, structure, physical processes and history. It examines rocks, minerals, tectonic plates, mountains, ocean basins, geothermal activity, magnetic fields and the deep interior of the planet. Geologists use rock layers, fossils, seismic waves, mineral chemistry, magnetic records, satellite measurements and ocean-floor surveys to reconstruct how Earth formed and how it continues to evolve.

The guides below are organized from the deepest parts of the planet to its surface landscapes, ocean basins and geological history. Earth’s Interior and Internal Heat Explore Earth’s crust, mantle, outer core and inner core, and discover how primordial heat, radioactive decay, mantle convection, plumes and deep reservoirs power the planet from within. Explore Earth’s Interior and Internal Heat Geothermal Systems Explained Learn how underground heat and circulating water create hot springs, geysers, fumaroles, mud pots, steam vents, travertine terraces and hydrothermal alteration. Explore Geothermal Systems Related: Yellowstone Geysers and Hydrothermal Features Magnetic Anomalies and Pole Shift Explained Discover how Earth’s geodynamo generates the magnetic field, why the magnetic poles drift, how reversals and excursions occur, and what the South Atlantic Anomaly means for satellites and technology. Explore Magnetic Anomalies and Pole Shift Rock Formations and Landforms Explained From mountains and canyons to hoodoos, arches, basalt columns, sea stacks, monoliths and moving rocks, discover how tectonics, weathering, rivers, glaciers, waves and wind sculpt Earth’s surface. Explore Rock Formations and Landforms Ocean Geology and the Seafloor Explained Explore oceanic crust, seafloor spreading, abyssal plains, mid-ocean ridges, trenches, fracture zones, seamounts, submarine canyons, pockmarks and ocean-floor mapping. Explore Ocean Geology and the Seafloor Related guides: Submarine Volcanoes and Seamounts Hydrothermal Vents Explained Methane Seeps Explained Geologic History of Earth Explained Travel through 4.54 billion years of Earth history—from planetary formation and the Hadean to the rise of oxygen, Snowball Earth, supercontinents, dinosaurs, ice ages and the modern world. Explore the Geologic History of Earth Lost Continents and Microcontinents Explained Explore Zealandia, Mauritia, Greater Adria, Argoland, the Seychelles and other fragments of continental crust—and learn the difference between genuine tectonic reconstructions and myths about Atlantis-style sunken continents. Explore Lost Continents and Microcontinents Choose the Right Geology Guide How These Geological Systems Connect Earth’s geological systems do not operate independently. Internal heat drives mantle motion and contributes to plate tectonics. Moving plates create mountains, ocean basins, faults, volcanic regions and geothermal systems. At the surface, rivers, glaciers, waves, wind and weathering reshape the rocks produced or uplifted by tectonic activity. Beneath the oceans, new crust forms at mid-ocean ridges and older crust is recycled at trenches. Over billions of years, these processes reorganize continents and oceans, alter climate and atmospheric chemistry, and create the environments in which life evolves. Frequently Asked Questions About Geology Geology is the science of Earth’s rocks, minerals, internal structure, surface features, physical processes and history. Earth is approximately 4.54 billion years old. Earth consists of the crust, mantle, liquid outer core and solid inner core. Earth’s internal heat comes mainly from energy retained since planetary formation and the radioactive decay of isotopes within the planet. Most of the mantle is solid rock, but it can flow slowly over geological time. A geothermal system forms where underground heat interacts with water, fractures and permeable rock. Earth’s magnetic field is generated mainly by the movement of electrically conductive liquid iron in the outer core. Yes. The magnetic poles drift, and the magnetic field has reversed polarity many times during Earth’s history. Landforms develop through tectonic uplift, volcanism, weathering, erosion, rivers, glaciers, waves, wind and gravity. Oceanic crust is dense, basalt-rich crust formed mainly at mid-ocean ridges and recycled at subduction zones. Continental drift is the movement of continents as parts of tectonic plates. A supercontinent is a large landmass formed when most or many continental blocks join together. Yes, in a geological sense. Continental fragments can become submerged, isolated, buried or incorporated into mountain belts. Zealandia is a large, mostly submerged region of continental crust in the southwest Pacific that includes New Zealand and New Caledonia. Geology helps explain natural hazards, water supplies, mineral resources, landscapes, climate history and the physical evolution of Earth. Explore Related Earth Oddities Hubs Explore faults, tectonic settings, seismic hazards, monitoring and historic earthquakes. Discover eruption types, volcanic hazards, monitoring systems and major volcanic regions. Strange Natural Phenomena Investigate unusual natural events involving water, ice, biological activity and rare landscapes. Human Impact on Earth Systems Explore pollution, contamination, industrial disasters, plastic waste, PFAS and radioactive hazards. Explore Earth From Its Core to Its Ancient Continents Geology connects Earth’s internal heat, magnetic field, moving plates, surface landscapes, ocean basins and deep-time history. Use the guides above to explore each major part of the planet’s geological system in greater detail. Terms of Service affiliate disclaimer CONTACT//REPORT Privacy Overview