This page lists 57 geological features that start with T, running from “Table Mountain” to “Tyrrhenian Basin.” The list covers mountains, volcanoes, glacial deposits, coastal landforms, rock types, ocean trenches and even a few features on other planets. Use it for school projects, travel planning, trivia or to learn how landscapes take shape.
Geological features are the natural landforms and rock formations that make up Earth’s surface and the ground beneath it. In 1815, the eruption of “Tambora” in Indonesia was so powerful that it cooled the global climate and caused the “Year Without a Summer” in 1816.
Below you’ll find the table with the feature, region, characteristics and description for each entry.
Feature: The name of each landform, rock type or geological structure, so you can quickly spot the one you want to look up.
Region: Where you can find each feature, from a specific country or mountain range to worldwide locations, so you can place it on a map.
Characteristics: A short summary of the key traits, such as shape, size or rock type, that helps you recognize and compare features at a glance.
Description: A brief explanation of how each feature forms and why it matters, with notable facts and examples that make it easier to remember.
Geological features
| Feature | Region | Characteristics |
|---|---|---|
| Table Mountain | South Africa | Flat-topped sandstone mountain |
| Tablelands | Worldwide | Flat, elevated terrain |
| Tafoni | Worldwide, especially coasts and deserts | Honeycomb-like cavities in rock |
| Taiga Soil Permafrost | Northern Eurasia and North America | Frozen ground beneath cold forests |
| Talus | Mountain slopes worldwide | Pile of broken rock fragments |
| Talus Cone | Mountain slopes worldwide | Cone-shaped rock debris pile |
| Tarn | Glaciated mountains worldwide | Small mountain lake in a hollow |
| Tectonic Plate | Global | Large moving slab of crust |
| Tectonic Basin | Global | Depression formed by crustal movement |
| Tell | Middle East | Mound built up over time |
| Terminal Moraine | Glaciated regions worldwide | Ridge of debris at glacier’s furthest reach |
| Terrace | River valleys and coasts worldwide | Step-like flat surface |
| Tepui | Venezuela, Guyana, Brazil | Flat-topped sandstone mesas with sheer cliffs |
| Thermal Spring | Worldwide, volcanic regions | Naturally heated water source |
| Thrust Fault | Mountain belts worldwide | Low-angle fracture where older rock rides over younger |
| Tidal Flat | Coastlines worldwide | Muddy or sandy area exposed at low tide |
| Tidal Inlet | Barrier coasts worldwide | Channel connecting a lagoon to the sea |
| Till | Glaciated regions worldwide | Unsorted mix of clay, sand, gravel and boulders |
| Tillite | Worldwide, ancient glacial deposits | Hardened glacial till |
| Tombolo | Coastlines worldwide | Sand or gravel bar linking an island to the mainland |
| Tor | Dartmoor, England, and granite uplands worldwide | Rocky outcrop on a hilltop |
| Tower Karst | Southern China, Vietnam, Thailand | Steep isolated limestone hills |
| Transform Fault | Mid-ocean ridges and plate boundaries | Plates slide horizontally past each other |
| Travertine Terraces | Pamukkale, Turkey; Mammoth Hot Springs, USA | White stepped pools of mineral deposits |
| Trench | Pacific Ocean and other ocean basins | Deep, narrow ocean depression |
| Tsingy | Madagascar | Sharp limestone needle forests |
| Tufa | Mono Lake, USA; Pamukkale, Turkey | Porous limestone from spring water |
| Tuff | Volcanic regions worldwide | Rock made of compacted volcanic ash |
| Tuff Ring | Volcanic regions worldwide | Low circular ridge of volcanic ash |
| Tundra Polygons | Arctic and subarctic regions | Patterned ground in frozen soil |
| Tunnel Valley | Formerly glaciated northern Europe and North America | Long channel cut beneath ice |
| Turbidite | Deep ocean floors worldwide | Layered rock deposited by underwater avalanches |
| Turbidity Current | Continental slopes worldwide | Underwater flow of sediment-laden water |
| Turtle Mountain | Alberta, Canada | Limestone mountain with a famous rockslide |
| Twin Peaks Volcano | Worldwide | Paired volcanic summits |
| Taupo Volcanic Zone | North Island, New Zealand | Active volcanic and geothermal belt |
| Tambora | Sumbawa, Indonesia | Stratovolcano with a huge caldera |
| Tengger Caldera | East Java, Indonesia | Large volcanic caldera with a sea of sand |
| Teide | Tenerife, Canary Islands | Volcano and Spain’s highest peak |
| Tibesti Mountains | Chad and Libya | Volcanic massif in the Sahara |
| Tibetan Plateau | Central Asia | Vast high-altitude plateau |
| Tien Shan | Central Asia | Long mountain range |
| Tian Shan Glaciers | Central Asia | Ice masses in a high mountain range |
| Tongariro | North Island, New Zealand | Active volcanic complex |
| Torres del Paine | Patagonia, Chile | Granite spires and glacial valleys |
| Transantarctic Mountains | Antarctica | Long mountain range dividing the continent |
| Trap Rock | Deccan, India; Siberia; Columbia Plateau | Stepped basalt lava layers |
| Tristan da Cunha | South Atlantic Ocean | Remote volcanic island |
| Tsunami Deposit | Coastlines worldwide | Sand sheet left by ocean waves |
| Tunguska Crater Field | Siberia, Russia | Site of a 1908 air burst |
| Tarim Basin | Western China | Large desert basin |
| Taklamakan Desert | Xinjiang, China | Large sand sea in a basin |
| Tanganyika Rift | East Africa | Deep rift valley lake basin |
| Teton Range | Wyoming, USA | Young fault-block mountains |
| Tonga Trench | South Pacific Ocean | Second deepest ocean trench |
| Tharsis Bulge | Mars | Giant volcanic plateau |
| Tyrrhenian Basin | Mediterranean Sea | Deep sea basin |
Descriptions
Table Mountain
A flat-topped mountain overlooking Cape Town, made largely of resistant sandstone. Its level summit is often covered by a cloud “tablecloth.”
Tablelands
High, flat-topped areas of land bordered by steep slopes or cliffs. They form where erosion strips away surrounding terrain but leaves a hard cap rock.
Tafoni
Small cave-like hollows and pits that form in cliffs and boulders. Salt crystals growing in the rock gradually break it apart from inside.
Taiga Soil Permafrost
Frozen ground that lies under much of the northern evergreen forest belt. It stays frozen for years and shapes how water drains and plants grow.
Talus
A sloping pile of loose rock fragments that collects at the base of a cliff. The debris falls from above through frost wedging and rockfalls.
Talus Cone
A cone-shaped heap of rubble that builds up beneath a gully or cleft in a cliff. Rocks funnel down the channel and fan out at the bottom.
Tarn
A small lake that fills a bowl-shaped hollow left behind by a glacier. Tarns are common in the Alps, the Rockies and the Lake District.
Tectonic Plate
One of the giant slabs of rock that make up Earth’s outer shell. Their slow movement causes earthquakes, volcanoes and mountain building.
Tectonic Basin
A low area of land formed when the crust stretches, sinks or folds. These basins often collect sediment over millions of years.
Tell
A mound created by repeated layers of human settlement. It is a landform as much as an archaeological one, and rises well above the surrounding plain.
Terminal Moraine
A ridge of rock and sediment pushed forward by a glacier and left behind when it stops advancing. Long Island, New York, sits on one.
Terrace
A flat, step-like ledge along a river valley or coastline. Terraces mark former river or sea levels left higher as the land rose or the water dropped.
Tepui
Table-top mountains of the Guiana Highlands that rise abruptly from the jungle. Their isolated tops host many plants found nowhere else.
Thermal Spring
A spring where groundwater heated by deep rock or magma rises to the surface. Many are used for bathing and some are rich in minerals.
Thrust Fault
A fault where one block of rock is pushed up and over another at a shallow angle. Thrust faults are common in the Himalayas and Alps.
Tidal Flat
A broad, flat stretch of coast that is covered at high tide and exposed at low tide. These areas are important feeding grounds for birds.
Tidal Inlet
A narrow channel between barrier islands that lets tides flow in and out of a bay or lagoon. Inlets can migrate or close over time.
Till
The jumbled sediment deposited directly by glacier ice. It contains everything from fine clay to huge boulders in no particular order.
Tillite
Rock formed when old glacial till turned to stone. Tillites provide evidence of ancient ice ages, including some from when Africa was near the pole.
Tombolo
A narrow strip of sand or shingle that connects an island to the shore. It builds up as waves bend around the island and drop sediment.
Tor
A freestanding pile of weathered rock crowning a hill. Tors are found on moors in southwest England and in granite landscapes elsewhere.
Tower Karst
Tall, steep-sided limestone hills that rise from flat plains. The dramatic landscapes around Guilin and Ha Long Bay are famous examples.
Transform Fault
A fracture where two tectonic plates slide sideways past one another. California’s San Andreas Fault is the best-known example.
Travertine Terraces
Layered, stair-like pools built from calcium carbonate left by flowing hot spring water. They form striking white formations that look like frozen waterfalls.
Trench
A long, steep-sided canyon on the sea floor where one plate dives beneath another. The Mariana Trench holds the deepest point on Earth.
Tsingy
Jagged limestone spires that form a maze of blades and pinnacles. The Tsingy de Bemaraha is a UNESCO World Heritage Site.
Tufa
A soft, porous rock that forms when calcium carbonate precipitates from spring or lake water. Mono Lake in California has famous towers of it.
Tuff
A rock formed from volcanic ash that has been squeezed and cemented together. It is light and easy to carve, so it has been used for building and cave homes.
Tuff Ring
A wide, low ring of ash and rock fragments around a volcanic vent. It forms when rising magma meets water and explodes.
Tundra Polygons
Many-sided patterns that appear on the ground in cold regions. They form as frozen soil cracks and expands over many seasons.
Tunnel Valley
A long, narrow valley carved by meltwater flowing under an ice sheet. Many are now filled with lakes or sediment.
Turbidite
A sedimentary deposit left by a turbidity current, a fast underwater flow of sediment. Layers grade from coarse at the bottom to fine at the top.
Turbidity Current
A fast-moving, dense flow of water and sediment that races down the sea floor. These currents carve submarine canyons and can snap seabed cables.
Turtle Mountain
A mountain near the town of Frank, where a huge 1903 rockslide buried part of the community. It is still monitored for movement.
Twin Peaks Volcano
A volcano with two adjacent summits, often formed by separate vents or a collapse of an older cone. Examples include sets of neighbouring cones in Iceland and the Andes.
Taupo Volcanic Zone
A region of intense volcanic activity running through the centre of New Zealand’s North Island. It includes giant calderas and many geothermal fields.
Tambora
A volcano whose 1815 eruption was the largest in recorded history. It caused the “Year Without a Summer” across the Northern Hemisphere in 1816.
Tengger Caldera
A huge volcanic caldera containing several smaller cones, including Mount Bromo. A wide plain of volcanic sand lies on its floor.
Teide
A large volcano rising to 12,198 feet, the tallest mountain in Spain. It sits inside a vast caldera and is a national park.
Tibesti Mountains
A group of volcanic mountains in the central Sahara. Emi Koussi, its highest peak, reaches about 11,204 feet.
Tibetan Plateau
The world’s highest and largest plateau, averaging over 14,000 feet. It formed through the collision of India with Asia and feeds many major rivers.
Tien Shan
A major mountain system stretching across Kyrgyzstan, Kazakhstan, Uzbekistan and China. Its peaks exceed 24,000 feet and it holds many glaciers.
Tian Shan Glaciers
Glaciers in the Tian Shan range that supply water to dry lowland areas. Many are shrinking as the climate warms.
Tongariro
A volcanic complex with several craters, popular for the Tongariro Alpine Crossing hike. Its colourful crater lakes and steaming vents are a highlight.
Torres del Paine
Dramatic granite towers rising above lakes and glaciers in southern Chile. The spires were shaped by uplift of magma and later glacial erosion.
Transantarctic Mountains
A mountain range that cuts across Antarctica, separating East from West. It is one of the longest mountain chains in the world.
Trap Rock
Layers of basalt lava that form stair-like hillsides after repeated eruptions. The name comes from a Swedish word for stairs.
Tristan da Cunha
A remote volcanic island group rising from the mid-Atlantic seafloor. Its 6,765-foot peak is a volcano that erupted in 1961.
Tsunami Deposit
A layer of sand and debris laid down inland by a tsunami. Geologists use these deposits to learn about past tsunamis.
Tunguska Crater Field
A remote forested area in Siberia flattened by an air burst in 1908. Scientists still study the landscape and the sediments around it.
Tarim Basin
A huge basin that holds the Taklamakan Desert and is ringed by high mountains. It contains thick sediments and large oil and gas reserves.
Taklamakan Desert
A vast desert of shifting dunes in the Tarim Basin. Some dunes reach heights of over 300 feet.
Tanganyika Rift
A section of the East African Rift holding Lake Tanganyika, the second deepest lake on Earth. The basin is slowly pulling apart.
Teton Range
A steep mountain range that rises straight from the valley floor with no foothills. It formed along the Teton Fault and rises to 13,775 feet.
Tonga Trench
A deep trench near Tonga where the Pacific Plate dives beneath another plate. It reaches depths of more than 35,000 feet.
Tharsis Bulge
A vast region of Mars with enormous volcanoes, including Olympus Mons. It is one of the largest volcanic provinces in the solar system.
Tyrrhenian Basin
A deep basin between Italy, Sicily, Sardinia and Corsica. It is volcanically active and features seamounts and underwater volcanoes.