Armor, in hydrology and geography is the association of surface pebbles, rocks or boulders with stream beds or beaches. Most commonly hydrological armor occurs naturally; however, a man-made form is usually called riprap, when shorelines or stream banks are fortified for erosion protection with large boulders or sizable manufactured concrete objects. When armor is associated with beaches in the form of pebbles to medium sized stones grading from two to 200 millimeters across, the resulting landform is often termed a shingle beach. Hydrological modeling indicates that stream armor typically persists in a flood stage environment.^[1] Water covers 70% of the Earths surface. ... Sea wave polishing pebbles into rounded corners Pebbles For other uses, see Pebble (disambiguation). ... Boulder In geology, a boulder is a rock with grain size of usually no less than 256 mm (10 inches) diameter. ... The bed of this stream is made up of rocks, some very rounded (having had a longer life in the stream) and some not. ... Ninety Mile Beach Australia. ... Water covers 70% of the Earths surface. ... Riprap (also known as rip rap or shot rock) is rock or other material used to stabilize shore. ... Shore A shore or shoreline is the land at the edge of a large body of water, such as an ocean, sea, or lake. ... Severe soil erosion in a wheat field near Washington State University, USA. For erosion as an operation of Mathematical morphology, see Erosion (morphology) Erosion is displacement of solids (soil, mud, rock and other particles) by the agents of ocean currents, wind, water, or ice by downward or down-slope movement... Ninety Mile Beach Australia. ... A landform comprises a geomorphological unit. ... A shingle beach is a beach which is armoured with pebbles or small to medium sized cobbles. ... Flood stage is the point at which the surface of a river, creek, or other body of water has risen to a sufficient level to cause damage. ...

See also

• flood control
• Storm tide

A flood (in Old English flod, a word common to Teutonic languages; compare German Flut, Dutch vloed from the same root as is seen in flow, float) is an overflow of water, an expanse of water submerging land, a deluge. ... A storm tide is a tide with a high flood period caused by a storm. ...

References