Topography, Hydrology, and Mass Wasting Flashcards

Vocabulary practice flashcards covering topography formation, stream drainage patterns, hydrology terms, and types of mass wasting events based on the study guide.

Topography

The shape of the land surface that forms through processes such as weathering, erosion, deposition, uplift, flooding, volcanic activity, and tectonic movement.

Floods

Events that occur when too much water enters a stream or river channel and the channel cannot hold it, spreading out on floodplains and lower parts of rivers.

Landslides

The downhill movement of rock, soil, or sediment caused by gravity when slopes become unstable due to heavy rainfall, earthquakes, or steep slopes.

Sheetwash

A thin layer of water flowing over the ground surface that removes and transports sediment during rainfall.

Dendritic

A stream drainage pattern that looks like tree branches, forming where rock types are uniform and the land is gently sloped.

Radial

A drainage pattern where streams flow outward from a central high point like a volcano or mountain.

Rectangular

A drainage pattern with many right-angle bends caused by fractures or faults in rock.

Parallel

A drainage pattern characterized by streams flowing side-by-side in the same direction on steep slopes.

Trellis

A drainage pattern where main streams run parallel and smaller streams enter at right angles, common in folded mountains.

Competence

The maximum size of sediment a stream can carry.

Drainage divides

High areas of land that separate different drainage basins or watersheds.

Hyporheic zone

The area beneath and beside a stream where groundwater and stream water mix.

Perennial

A stream that is connected to the water table and flows year-round.

Ephemeral

A stream that is above the water table and only flows after rainfall.

Thalweg

The deepest and fastest-flowing part of a stream channel.

Slump

A type of landslide where a block of soil or rock moves downward along a curved surface, often looking like a backward-tilted block.

Dam

A barrier built across a river used to store or control water.

Mass wasting

The downhill movement of rock, soil, or sediment due to gravity.

Creep

The slowest type of landslide involving very slow movement of soil downhill on gentle slopes over long periods of time.

Rockfall

A mass movement where rocks fall freely from steep cliffs, common after weathering or earthquakes.

Mudflow

A fast-moving mixture of water and sediment that happens after heavy rain.

Debris flow

The rapid flow of rocks, mud, and water, commonly occurring on steep slopes.

Liquefaction

A process where water-saturated sediment loses strength during shaking (usually from earthquakes) and behaves like a liquid, triggering ground failure.

Saltation

The bouncing movement of sediment particles, typically sand-sized, along the stream bed.

Cut bank

The outside bend of a river where erosion occurs.

Point bar

The inside bend of a river where deposition occurs.

Meandering stream

A river characterized by winding curves and bends caused by continuous erosion and deposition.

Stream gradient

The measure of a stream's steepness, defined as the change in elevation over a certain distance.