This page lists 36 geological features that start with B, from “Badlands” to “Brine Pool.” The list covers landforms, rock types, and water features, from towering mountains to quiet sandy shores. People use this kind of knowledge in geography classes, hiking and travel planning, land use, and natural resource work.
Geological features are the natural shapes, structures, and materials that make up the surface of the Earth. They are built and reshaped by forces like volcanoes, water, wind, and ice. One famous example is the “Basalt Column” formation at the Giant’s Causeway in Ireland, which looks almost man-made.
Below you’ll find the table with the feature name, region, characteristics, and description for each entry.
Feature: The name of each geological feature, listed alphabetically, so you can quickly find the exact term you want to look up.
Region: Where in the world you can find the feature, including well-known places, which helps you connect each term to real locations.
Characteristics: A short set of key traits that sum up the feature, so you can compare similar landforms at a glance.
Description: A plain-language explanation of what the feature is and how it forms, so you understand it without any technical background.
Geological features
| Feature | Region | Characteristics |
|---|---|---|
| Badlands | Worldwide (notably North America, Argentina, Italy) | Eroded, barren, layered terrain |
| Barchan Dune | Deserts worldwide (Sahara, Namibia, Peru) | Crescent-shaped, wind-formed |
| Barrier Island | Coastlines worldwide (US Atlantic and Gulf coasts) | Long, narrow, sandy, coastal |
| Barrier Reef | Tropical seas (Australia, Belize) | Coral-built, offshore, long |
| Basalt Column | Ireland, Iceland, USA, Scotland | Hexagonal, volcanic, columnar |
| Basin | Worldwide | Low-lying, bowl-shaped, depression |
| Batholith | Worldwide (Sierra Nevada, Patagonia, Idaho) | Massive, igneous, intrusive |
| Bay | Coastlines worldwide | Coastal, curved inlet, sheltered |
| Bayou | Southern United States (Louisiana, Texas) | Slow-moving, marshy, swampy |
| Beach | Coastlines worldwide | Sandy or pebbly, shoreline, wave-shaped |
| Beach Ridge | Coastlines and lake shores worldwide | Elongated, sandy, wave-deposited |
| Bedding Plane | Worldwide | Sedimentary, layered, flat surface |
| Bedrock | Worldwide | Solid, underlying, ancient |
| Bench | Mountains and river valleys worldwide | Flat, step-like, elevated |
| Bergschrund | Glaciers worldwide (Alps, Himalayas, Andes) | Crevasse, icy, steep |
| Berm | Beaches worldwide | Raised, sandy, shoreline ridge |
| Biogenic Sediment | Ocean floors worldwide | Organic, fine-grained, deposited |
| Black Smoker | Mid-ocean ridges worldwide | Hydrothermal, deep-sea, mineral-rich |
| Block Mountain | Worldwide (Sierra Nevada, Black Forest) | Fault-bounded, uplifted, steep |
| Blowhole | Coastlines worldwide (Hawaii, Australia, New Zealand) | Sea cave, spouting, coastal |
| Blowout | Coastal dunes and dry plains worldwide | Wind-eroded, hollow, sandy |
| Bluff | River valleys and coastlines worldwide | Steep, high, cliff-like |
| Bog | Northern Europe, Canada, Russia, Ireland | Wet, acidic, peat-forming |
| Bolson | Southwestern United States, Mexico | Enclosed, desert, basin |
| Boulder Field | Mountains and cold regions worldwide | Rocky, frost-shattered, high-elevation |
| Braided River | New Zealand, Alaska, Himalayas, Iceland | Multi-channel, gravelly, shifting |
| Breakwater Reef | Tropical coasts worldwide | Coral, protective, nearshore |
| Butte | Southwestern United States (Monument Valley) | Isolated, flat-topped, steep-sided |
| Basalt Plateau | Worldwide (Deccan, Columbia River) | Volcanic, vast, flat |
| Boiling Mud Pot | Yellowstone (USA), Iceland, New Zealand | Geothermal, bubbling, acidic |
| Barrier Spit | Coastlines worldwide | Sandy, narrow, extended |
| Bornhardt | Australia, Brazil, Africa | Dome-shaped, granite, isolated |
| Bottomland | River valleys worldwide | Flat, fertile, floodplain |
| Braided Stream | Mountain and glacier outwash areas worldwide | Shallow, sediment-heavy, interlaced |
| Breccia | Worldwide | Rock, angular fragments, cemented |
| Brine Pool | Gulf of Mexico, Red Sea | Underwater lake, salty, deep-sea |
Descriptions
Badlands
Dry terrain where soft rock and clay have been cut into ridges, gullies, and canyons by wind and water. Little vegetation grows, so the colorful rock layers stay exposed.
Barchan Dune
A crescent-shaped sand dune with its horns pointing downwind. It forms where wind blows steadily from one direction and sand is limited.
Barrier Island
A long, narrow sandy island that runs parallel to the mainland coast. It shields the shore from storms and waves and shifts over time.
Barrier Reef
A long coral reef separated from the shore by a deep lagoon or channel. It forms a natural wall that breaks incoming ocean waves.
Basalt Column
A tall, many-sided rock pillar formed when thick lava flows cool and crack. The Giant’s Causeway is a famous example.
Basin
A large bowl-shaped depression in the Earth’s surface. Basins can collect water, sediment, or both, and often hold valuable resources such as oil and groundwater.
Batholith
A huge body of granite-type rock that cooled slowly deep underground. It is later exposed when overlying rock erodes away.
Bay
A broad curved inlet of the sea where the land wraps around the water. Bays often offer calm water and make good natural harbors.
Bayou
A slow, sluggish waterway found in low, flat wetlands, often branching off a river or lake. It is typically lined with cypress trees and thick vegetation.
Beach
A strip of sand, gravel, or pebbles along the edge of a sea, lake, or river. Waves and currents constantly reshape it.
Beach Ridge
A low ridge of sand or gravel piled up by waves along a shoreline. Series of ridges can record how the coast has moved over time.
Bedding Plane
The flat surface that separates one layer of sedimentary rock from the next. It marks a pause or change in how sediment was laid down.
Bedrock
The solid rock that lies beneath loose soil and sediment. It forms the foundation of the landscape.
Bench
A flat, step-like ledge on a hillside or valley wall. Benches are often left behind by old river levels or glaciers.
Bergschrund
A large crevasse at the top of a glacier where moving ice pulls away from the stagnant ice or rock above. Climbers often must cross it.
Berm
A raised, nearly flat ridge of sand or gravel on a beach, marking the reach of normal high tides or storm waves.
Biogenic Sediment
Sediment made from the remains of living things, such as shells and microscopic plankton skeletons. It builds up on the sea floor over long periods.
Black Smoker
A deep-sea vent that spews hot, dark, mineral-laden water. The minerals solidify into chimney-like towers around the vent.
Block Mountain
A mountain formed when a block of crust is pushed up between faults, or when surrounding land drops. It often has steep sides and a flat top.
Blowhole
An opening in coastal rock where waves force water and air up through a hole, sending spray high into the air.
Blowout
A bowl-shaped hollow in sand or soil carved out by wind where vegetation has been lost.
Bluff
A high, steep bank or cliff, often overlooking a river, lake, or sea. It is usually broader and less sheer than a true cliff.
Bog
A wetland with soggy, acidic ground built from thick layers of partly decayed plants called peat. It is fed mostly by rain.
Bolson
A flat desert basin surrounded by mountains, with no outlet to the sea. Water drains inward and often forms a temporary lake.
Boulder Field
A wide area covered with large angular rocks, often created by repeated freezing and thawing that cracks bedrock apart.
Braided River
A river that splits into many shifting channels separated by small gravel or sand bars. It forms where there is lots of sediment and variable flow.
Breakwater Reef
A coral or rock formation close to shore that blunts incoming waves, working much like a man-made breakwater.
Butte
A small, isolated hill with a flat top and steep sides. It is a remnant left after surrounding rock has been eroded away.
Basalt Plateau
A broad upland made of thick layers of lava that spread across large areas. Some of the biggest on Earth formed from massive eruptions.
Boiling Mud Pot
A hot spring where limited water mixes with clay and volcanic gas, creating bubbling pools of thick mud.
Barrier Spit
A narrow strip of sand attached to land at one end and extending into open water, built by longshore currents.
Bornhardt
A bare, dome-shaped rock hill that rises sharply from a surrounding plain. Uluru-like inselbergs are classic examples.
Bottomland
Low-lying land beside a river, built from sediment deposited during floods. It is often rich farmland.
Braided Stream
A shallow stream that divides and rejoins around gravel bars, common where rivers carry more sediment than they can move.
Breccia
A rock made of sharp, broken fragments cemented together. It often forms in fault zones, landslides, or volcanic explosions.
Brine Pool
A pool of extremely salty water on the sea floor that is denser than the surrounding ocean, creating a shoreline-like edge underwater.