This list includes 70 Earth science words that start with B, from “B horizon” to “Butte”. They cover landforms, soils, rocks, processes, and climate terms useful in education, fieldwork, and communication.

Earth science words that start with B are terms used to name Earth’s materials, processes, and landforms. For example, “Butte” became a cultural symbol in western mapping and landscape writing.

Below you’ll find the table with the following columns: Word, Definition, Category, Example, Further reading.

Word: The exact term as used in Earth science; you can scan quickly to find specific vocabulary.

Definition: A concise one- or two-sentence explanation of the term; you use this to understand meaning and classroom context.

Category: Shows the general topic, like landform, process, or material, so you can group and compare related words.

Example: Gives a short real-world instance or location that illustrates how the term appears in nature or study.

Further reading: Links to deeper articles or glossaries so you can explore reliable sources and expand your understanding.

Earth science words that start with B

TermCategoryFieldTypical units/scale
Basinlandformgeomorphologykm to 1,000s km
Baylandformoceanographykm
Beachlandformgeomorphologym to km shoreline
Barrier islandlandformgeomorphologykm long
Bedrockrockgeologym to km thickness
Bedloadprocesshydrologykg/s, m3/s
Beddingrockgeologycm to m layers
B horizonsoilsoil sciencecm depth
Barchanlandformgeomorphologym to km
Basaltrockgeologyg/cm3, Ma
Base levelprocessgeomorphologym elevation
Bathymetrymeasurementoceanographym, km
Batholithrockgeologykm scale
Beach cusplandformgeomorphologym spacing
Bauxitemineralgeology% Al2O3
Bedformlandformgeomorphologycm to m
Biotitemineralgeologyg/cm3
Black smokeroceanoceanography°C, m depth
Blowoutlandformgeomorphologym to 100s m
Blue schistrockgeologykm scale
Boreholemeasurementgeologym depth
Brackish wateroceanhydrologyppt, PSU
Breakeroceanoceanographym height
Bulk densitymeasurementsoil scienceg/cm3
Buoyancyprocessgeophysicsdimensionless, N
Burial metamorphismprocessgeologyMa, km depth
Buttelandformgeomorphologym height
Basementrockgeologykm depth
Barrier reeflandformoceanographykm
Back-arc basinlandformgeologykm wide
Backwashprocessoceanographym/s
Barlandformgeomorphologym to km
BarometermeasurementmeteorologyhPa, Pa
Baroclinicprocessmeteorologykm scale
Beaufort scalemeasurementmeteorologyscale 0–12
Banded iron formationrockgeologym to km thickness
Bifurcationprocesshydrologym scale
Bogsoilsoil sciencem peat depth
Bolidehazardgeologym to km size
Boundary layeratmospheremeteorologym to km
Brineoceanoceanographyppt, PSU
Bulk modulusmeasurementgeophysicsPa
Buoymeasurementoceanographym position, m/s
Briniclelandformoceanographycm to m
Blue holeoceanoceanographym depth
Braided riverlandformgeomorphologym to km width
Bridgmanitemineralgeophysicsg/cm3
Brecciarockgeologycm to m clasts
Block faultingprocessgeologykm scale
Benthicoceanoceanographym depth
Bergschrundlandformgeomorphologym
Bitumenrockgeology%
Bioturbationprocessgeologycm to m
Black carbonatmosphereclimatologyµg/m3
Black shalerockgeologym thickness
Box coremeasurementoceanographym, cm sample
Bolsonlandformgeomorphologykm scale
Bedrock weatheringprocessgeomorphologymm/yr
Breakwaterlandformgeomorphologym to km
BackscattermeasurementoceanographydB
Blowholelandformgeomorphologym
Brecciationprocessgeologycm to m
Bentonitemineralsoil science% clay
Bajadalandformgeomorphologym to km
Benchlandformgeomorphologym to km
Breachhazardhydrologym3/s
Blind faulthazardgeologykm scale
Boulderlandformgeomorphologym size
Brine pooloceanoceanographym, °C
Basin inversionprocessgeologykm scale

Descriptions

Basin
A large low area where sediments collect or water pools, including drainage basins and ocean basins.
Bay
A coastal indentation where the sea extends into land, often sheltered and important for ecosystems and shipping.
Beach
A shoreline made of sand, pebbles, or cobbles, shaped and sorted by waves and tides.
Barrier island
A narrow, sandy island parallel to shore that protects the coast and shifts with storms and tides.
Bedrock
The solid rock layer beneath soil or sediment that forms the Earth’s crustal foundation.
Bedload
Coarse sediment particles moved along a streambed by rolling, sliding, or hopping.
Bedding
Layering in sedimentary rocks produced by changes in deposition over time.
B horizon
The subsoil layer beneath topsoil, often richer in clay and minerals leached from above.
Barchan
A crescent-shaped sand dune formed by a consistent wind direction and limited sand supply.
Basalt
A dark, fine-grained volcanic rock that makes up much of the ocean crust and volcanic flows.
Base level
The lowest elevation to which a stream can erode, commonly taken as sea level.
Bathymetry
Measurement and mapping of seafloor depth and underwater topography.
Batholith
A very large, deep-seated intrusive igneous body formed from cooled magma.
Beach cusp
Regular crescentic features on a beach formed by wave-sediment interactions.
Bauxite
A weathering-derived aluminum ore formed in tropical soils and used to produce aluminum.
Bedform
Small-scale structures like ripples and dunes formed on sediment beds by flowing water or air.
Biotite
A common dark mica mineral found in igneous and metamorphic rocks.
Black smoker
A seafloor hydrothermal vent that emits hot, mineral-rich fluids and builds chimney structures.
Blowout
A wind-eroded depression in a dune field where sand has been removed.
Blue schist
A high-pressure, low-temperature metamorphic rock often blue from minerals like glaucophane.
Borehole
A drilled hole used to sample subsurface rocks, fluids, or to place monitoring equipment.
Brackish water
Water with salinity between fresh and seawater, typical of estuaries and some coastal aquifers.
Breaker
A wave that collapses as it enters shallow water and transfers energy to the shore.
Bulk density
Mass per unit volume of soil or sediment, important for water and root relationships.
Buoyancy
An upward force a fluid exerts on an object, depending on displaced fluid density.
Burial metamorphism
Metamorphism caused by deep burial and heating of sediments without major tectonic deformation.
Butte
An isolated, steep-sided hill with a flat top, smaller than a mesa.
Basement
Older, often crystalline rocks that lie beneath younger sedimentary layers.
Barrier reef
A coral reef running parallel to a shore and separated from it by a lagoon.
Back-arc basin
A seafloor basin formed behind a volcanic arc at a convergent plate margin.
Backwash
Water flowing seaward down a beach face after a wave breaks.
Bar
A ridge of sand or gravel deposited by currents in rivers or nearshore zones.
Barometer
An instrument that measures atmospheric pressure, useful for weather forecasting.
Baroclinic
A fluid state where density varies with both temperature and pressure, driving weather systems and instabilities.
Beaufort scale
A descriptive scale for wind strength and sea conditions, from calm to hurricane-force.
Banded iron formation
Ancient layered sedimentary rocks rich in iron, formed under early Earth ocean conditions.
Bifurcation
A point where a river splits into two or more separate channels.
Bog
A waterlogged, acidic peatland dominated by mosses and low-nutrient conditions.
Bolide
A large, bright meteor that explodes in the atmosphere and can produce impact effects.
Boundary layer
The lowest part of the atmosphere directly influenced by the Earth’s surface, affecting turbulence and weather.
Brine
Highly saline water often found in evaporite basins or under sea ice, denser than normal seawater.
Bulk modulus
A material property describing resistance to uniform compression, used in studies of Earth’s interior.
Buoy
A floating instrument platform that measures ocean conditions like temperature, waves, and currents.
Brinicle
An underwater icicle formed when very cold, salty brine sinks and freezes seawater beneath ice.
Blue hole
A deep, steep-walled submarine sinkhole, notable for clear water and distinctive marine records.
Braided river
A river system with multiple intertwining channels separated by transient bars and islands.
Bridgmanite
A high-pressure silicate mineral believed to be the most abundant in Earth’s lower mantle.
Breccia
A rock composed of angular fragments cemented together, formed by collapse, faulting, or volcanism.
Block faulting
Crustal deformation where large blocks move along faults, creating horsts and grabens.
Benthic
Relating to the bottom of a water body and the organisms or processes that occur there.
Bergschrund
A large crevasse at the head of a glacier separating moving ice from the mountain slope.
Bitumen
A viscous, carbon-rich residue in oil sands or source rocks, important for unconventional petroleum.
Bioturbation
Reworking of sediments by organisms, which alters layering and preserves biological signals.
Black carbon
Soot-sized particles from incomplete combustion that absorb sunlight and influence climate and air quality.
Black shale
Organic-rich sedimentary rock that can be a source of hydrocarbons and preserve ancient environments.
Box core
A sampling device that collects near–undisturbed square samples of seafloor sediment.
Bolson
An enclosed desert basin with internal drainage, common in arid regions.
Bedrock weathering
Breakdown of solid rock at or near Earth’s surface by physical and chemical processes.
Breakwater
A built structure that reduces wave energy to protect a shoreline or harbor.
Backscatter
Strength of sound or light reflected back to a sensor, used to map seafloor and sediments.
Blowhole
A coastal vent where waves force water or air upward through a sea cave opening.
Brecciation
The breaking and fragmentation of rock into angular pieces during deformation or impact events.
Bentonite
A swelling clay formed from altered volcanic ash, important in drilling and sealants.
Bajada
A broad apron where multiple alluvial fans merge at the base of mountain fronts in arid zones.
Bench
A relatively flat terrace or step on a slope, often formed by erosion or deposition.
Breach
A failure or opening in a levee, dam, or barrier that allows sudden water release and flooding.
Blind fault
A fault that does not break the surface, posing seismic risk because it is hidden from view.
Boulder
A large rock fragment transported and deposited by gravity, ice, or water.
Brine pool
A localized seafloor depression filled with extremely saline water, chemically distinct from surrounding seawater.
Basin inversion
Tectonic uplift and deformation that reverses prior subsidence of a sedimentary basin.
If you think there is a missing term, let us know using the contact form.