Chapter 18 Ocean MotionChapter 18 Ocean MotionChapter 19 OceanographyChapter 19 Oceanography

Chapter 18.3 and 19.1 Notes Chapter 18.3 and 19.1 Notes GuideGuide

WavesWaves

A A __wave_____wave___ is a rhythmic movement that is a rhythmic movement that carries energy through matter in space.carries energy through matter in space.

In the ocean, waves move through In the ocean, waves move through _seawater__._seawater__. Waves look like Waves look like __hills____hills__ and valleys.and valleys.

Waves are created by friction from Waves are created by friction from ___wind_____.___wind_____.

Waves ContinuedWaves Continued The The __crest_______crest_____ is the high point of a wave. is the high point of a wave. The The __trough_____trough___ is the low point of a wave. is the low point of a wave. Wavelength Wavelength is the horizontal distance between is the horizontal distance between

the crests or between the troughs of two waves.the crests or between the troughs of two waves. Wave Wave heightheight is the vertical distance between is the vertical distance between

crest and trough.crest and trough. Half the distance of the wave height is called the Half the distance of the wave height is called the

amplitude amplitude of a wave.of a wave.

Wave MovementWave Movement

As a wave passes, only As a wave passes, only _energy__energy_ moves moves forward, while the water molecules move forward, while the water molecules move around in around in _circles___circles__ and stay near their and stay near their original position.original position.

Waves break as they approach the shore, Waves break as they approach the shore, and drag along the bottom, causing them and drag along the bottom, causing them to eventually collapse. to eventually collapse.

Waves move in circles!!Waves move in circles!!

Wave BreakingWave Breaking

Formation of WavesFormation of Waves

When wind blows across a body of water, When wind blows across a body of water, wind wind __energy____energy__ is transferred to the is transferred to the water. If the wind speed is great enough, water. If the wind speed is great enough, the water begins to pile up and a the water begins to pile up and a __wave____wave__ is formed. is formed.

TidesTides

The rise and fall in sea level is called a The rise and fall in sea level is called a _tide___._tide___. A tide is giant A tide is giant __wave_____wave___ produced by the produced by the _gravitational____gravitational___ pull of pull of the the _Earth___Earth__ and the and the __Sun__.__Sun__.

A tide is a form of wave, but it is A tide is a form of wave, but it is _thousands___thousands__ of meters long. of meters long.

As the crest of the wave approaches As the crest of the wave approaches shore, sea level appears to shore, sea level appears to _rise__._rise__. This is This is _high_ _tide__._high_ _tide__.

TidesTides

As the trough of the wave approaches As the trough of the wave approaches shore, sea level appears to _drop. This is shore, sea level appears to _drop. This is called called __low__ __tide___.__low__ __tide___.

The The _tidal__ _range__tidal__ _range_ is the difference is the difference between the level of ocean at high and low between the level of ocean at high and low tide.tide.

Gravitational PullGravitational Pull The The ___moon______,___moon______, not the __ not the __sun______sun______ has most effect on the has most effect on the

tides.tides. However, the sun can However, the sun can __increase_______increase_____ or or ___decrease_______decrease____ the the

moon’s effects of tides.moon’s effects of tides. When the sun, earth and moon are lined up together, the combined When the sun, earth and moon are lined up together, the combined

pull causes pull causes ___spring ____ __tide_______.___spring ____ __tide_______. During spring tides, the During spring tides, the high tides are high tides are __higher_________higher_______ and the low tides are and the low tides are __lower______lower____ than normal.than normal.

When the sun, earth and moon form a right angle, When the sun, earth and moon form a right angle, ___neap________neap_____ _tides______tides_____ occur. During neap tides, high tides are occur. During neap tides, high tides are __low_______low_____ and low tides are and low tides are _high________high_______ than normal than normal

Spring TideSpring Tide

Sun

New MoonEarth Full Moon

Spring Tide

Spring TideSpring Tide

Neap TideNeap TideNeap Tide

3rd Quarter

1st Quarter

EarthSun

Neap TideNeap Tide

Ocean TopographyOcean Topography

Map of Ocean TopographyMap of Ocean Topography

Continental Shelf

Continental Slope

Abyssal Plain

The Ocean BasinsThe Ocean Basins __Ocean_________Ocean_______ basins which are low areas of the basins which are low areas of the

Earth have many features. Earth have many features. -The -The ____continental__shelf________continental__shelf____ is the gradually sloping is the gradually sloping

end of a continent that extends under the ocean.end of a continent that extends under the ocean. -The -The ____ continental __slope___________ continental __slope_______ extends from the extends from the

outer edge of a continent shelf down to the ocean floor.outer edge of a continent shelf down to the ocean floor. -The -The ____ continental __ _rise_________ continental __ _rise_____ is an area of is an area of

sediment directly after the continental slope.sediment directly after the continental slope. -The -The __abyssal___ __plain_____abyssal___ __plain___ is the flat ocean floor that is the flat ocean floor that

are 4,000 to 6,000 m below the surface of the ocean.are 4,000 to 6,000 m below the surface of the ocean.

The Continental MarginThe Continental Margin

The Ocean BasinsThe Ocean Basins -A _-A _mid___-_ocean___mid___-_ocean___ ridge is an area in the ocean basin where ridge is an area in the ocean basin where

new ocean floor is formed.new ocean floor is formed. -A _-A _trench__trench__ is the deepest part of the ocean floor, and is defined is the deepest part of the ocean floor, and is defined

as a long, narrow, steep sided, depression where one crustal plate as a long, narrow, steep sided, depression where one crustal plate sinks beneath each other. sinks beneath each other.

-A -A __hydrothermal vent__hydrothermal vent_ is also called a black smoker and are _ is also called a black smoker and are commonly found near mid-ocean ridges or hot spots.commonly found near mid-ocean ridges or hot spots.

- A _- A _seamount__seamount__ is a undersea volcano that no longer erupts. is a undersea volcano that no longer erupts. - A _- A _guyot__guyot__ is a flap topped seamount. is a flap topped seamount. -A -A _submarine canyon__submarine canyon_ is a deeply incised, steep-walled, is a deeply incised, steep-walled,

commonly V-shaped in profile that is cut into the rocks and commonly V-shaped in profile that is cut into the rocks and sediments of the outer continental shelf and slope.sediments of the outer continental shelf and slope.

Submarine CanyonSubmarine Canyon

Seafloor FeaturesSeafloor Features

Seafloor FeaturesSeafloor Features

SonarSonar

_Sonar___Sonar__ – An acronym for sound – An acronym for sound navigation and ranging, an instrument navigation and ranging, an instrument used to locate objects under water by used to locate objects under water by reflecting sound waves.reflecting sound waves.

Mapping by sonar from ships.Mapping by sonar from ships. Mapping By sonar from satellitesMapping By sonar from satellites

SonarSonar

How Sonar is Used!How Sonar is Used!