Constructive and Destructive Forces (Erosion and Deposition) (copy)

Constructive Forces

Processes that build up landforms, such as volcanic activity and sediment deposition.

Destructive Forces

Processes that break down landforms, such as erosion and weathering. These often lower the elevation of surface features.

Erosion

The geological process in which earthen materials are worn away and transported by natural forces such as wind or water.

Deposition

the laying down of sediment carried by wind, flowing water, the sea or ice.

topographic maps/ contour maps

a map that accurately shows the shape and changing elevations of the land

agents of erosion/deposition

water, ice, wind, and gravity that cause the removal or deposition of sediment and soil.

surface features

produced by various processes such as erosion and deposition, including hills, valleys, and plains.

physical/mechanical weathering

Breaking rocks into smaller pieces without changing their chemical composition (e.g., ice wedging/freezing and thawing)

chemical weathering

Breakdown of rocks through chemical reactions, such as oxidation (rust), carbonation, or acids in rainwater

contour intervals

The vertical distance between contour lines indicating a change in elevation.

sinkhole

A depression produced in a region where soluble rock has been removed by groundwater

hot spot volacano

An area where material from deep in the mantle rises and then melts, forming magma

landslide

a slide of a large mass of dirt and rock down a mountain or cliff

gradient

the steepness of the slope of a stream or river

floodplain

an area along a river that forms from sediments deposited when the river overflows its banks

oxbow lake

a horseshoe-shaped body of water formed when a river breaks through the neck of a meander.

sediments

rock fragments that have been transported to a different location including: silt, sand, clay, pebbles, and boulders.

V shaped valley

a valley shaped like a “V” that is formed by the erosive action of a river or stream cutting through rock and soil over time.

U shaped valley

a valley shaped like a “U” that has been carved out by a glacier and had sediment removed.

delta

A triangular landform (wetland) made of sediment deposited where a river empties into a slower-moving or standing body of water like a lake or ocean

sand dune

A rolling hill or ridge of windblown sand built up through deposition.

abrasion

the process of wearing away surfaces through friction or impact, often caused by the movement of sediment.

moraine

A mound, ridge, or pile of unsorted sediment (till) deposited directly by a melting glacier.

buttes

steep, flat-topped hills that stand alone on a plain

striations

a small groove, scratch, ridge, or line that is part of a parallel series on a surface