Earth Science 11^th Edition Vocabulary Chapter 15

By Megan Andrews (GLY 1001 Student North Campus Fall 2006)

abrasion-the grinding and scraping of a rock surface by the friction and impact of rock particles carried by water, wind, or ice.

backshore- the inner portion of the shore lying landward of the high tide shoreline. It is usually dry, being affected by waves.

barrier island- a low elongated ridge of sand that parallels the coast.

baymouth bar- a sandbar that completely crosses a bay sealing it off from the open ocean.

beach- an accumulation of sediment found along the landward margin of the ocean or a lake.

beach drift - the transport of sediment in a zigzag pattern along a beach caused by the uprush of water from obliquely breaking waves.

beach face- the wet breaking surface that extends from the berm to the shoreline.

beach nourishment- the process by which large quantities of sand are added to the beach system to offset losses caused by wave erosion.

berm- the dry gently sloping zone on the backshore of a beach at the foot of the coastal cliffs or dunes.

breakwater- a structure protecting a near shore area.

coastline- coasts seaward edge the landward limit of the effect of the highest storm waves off the shore.

coriolis effect- the deflective force of earth's rotation on all free moving objects.

diurinal tidal pattern- tidal pattern exhibiting one high tide and one low tide during the tidal day, a daily tide.

emergent coast- a coast where land that has been formally below sea level has been exposed either because of a crustal uplift or a drop in sea level.

estuary- a partially enclosed coastal water body that is connected to the ocean. salinity here is measured reduced by the freshwater flow of rivers.

fetch- the distance that the wind traveled across the open water.

foreshore- that portion of the shore lying between the normal high and low water marks; the internal zone.

groin- a short wall built at a right angle to the shore to trap moving sand.

hard stabilization- any form of artificial structure built to protect a coast or to prevent the movement of sand along the beach.

longshore current- a near shore current that flows parallel to the shore.

marine terrace- a wave cut platform that as been exposed above sea level.

mixed tidal pattern- a tidal pattern exhibiting two high tides and two low tides per tidal day with a large in equality in high water heights, low water heights, or both.

neap tide- lowest tidal range occurring near the times of the 1st and 3rd quarter phases of the moon.

nearshore zone- the sone of the beach that extends from the low tide shoreline seaward where waves break at low tide.

offshore zone- the relatively flat submerged zone that extends from a breakerline to the edge of the continental shelf.

sea arch- an arch formed by wave erosion when caves on opposite

sea stack- an isolated mass of rock standing just off shore produced by wave erosion of a head land.

sea wall- a barrier constructed to prevent waves from reaching the area behind the wall. its purpose is to defend property from the force of breaking waves.

semidiurnal tidal patterns- 2 high tides and two low tides per tidal day with small inequalities between successive highs and successive lows, semidaily tide.

shore- seaward of the coast this zone extends from the highest level of wave action during the storms to the lowest tide level.

shoreline- the line that marks the contact between land and sea. It migrates up and down as the tide rises and falls.

spit- an elongated ridge of sand that projects from the land in to the mouth of the adjacent bay.

spring tide- highest tidal range that occurs near the times of the new and full moons.

submerged coast- a coast with a form that is largely the result of the partial drowning of a former land surface either because of a rise of sea level or subsidence of the crust or both.

surf- a collective term of breakers also the wave activity in the area between the shoreline and the outer limit of breakers.

thermonaline circulation- movements of ocean water caused by density differences brought about by variations in temperature and salinity.

tidal current- alternating horizontal movement of water associated with the rise and fall of tide.

tidal delta- a delta like feature created when a rapidly moving tidal current emerges from a narrow inlet and slows depositing its load of sediments.

tidal flat- marshy or muddy area that is uncovered by the rise and fall of tide.

tide- periodic change in the elevation of the ocean surface.

tomboro- a ridge of sand that connects an island to the mainland or to another island.

upwelling- the rising of cold water from deeper layers to replace warmer water that has moved away.

wave-cut-cliff- a seaward facing cliff along a steep shoreline formed by wave erosion at its base, mass, and wasting.

wave height- vertical distance between the trough and crest of a wave.

wavelength- horizontal distance separating successive crests or troughs.

wave period- the time interval between the passage of successive crests at a stationary point.

wave refraction- process by which the portion of a wave in shallow water slows. causing the wave to bend and tend to align itself with the underwater contours.