Unit 2 Flashcards
What are Continental Margins consisted of?
Shelves-Slopes-Rises SSR
Describe everything about Shelves
The edges of the continents slope down from the shore into the ocean.
The part of the continent located under the water is known as the continental shelf.
In some places, the continental shelf is fairly shallow and in other places it becomes very deep.
Covered in sediments from land.
Most commercial exploitation from the sea, such as metals and hydrocarbons and oil, takes place at the continental shelf.
Sunlight penetrates the shallow waters, and many kinds of organisms flourish from microscopic algae to giant kelp; this the brings lots of animals.
Describe everything about slopes.
Gets deep quickly- where shelf goes down to the sea floor.
The steep slope where the continental shelf drops to the bottom of the ocean floor is called the continental slope.
Describe everything about Submarine Canyons
A steep-sided valley cut into the sea floor of the continental slope.
Some are large extensions of terrestrial rivers.
Describe everything about Ocean Basins
Located on either side of the mid-ocean ridge is the ocean basin.
Also known as the abyssal plain- lots of sediments are found here.
It’s made up of low hills (abyssal hills) and flat plains (abyssal plains).
This is the deepest part of the ocean floor.
Describe everything about Seamounts.
Steep sided, underwater volcanoes that do not reach the surface- biological hotspots that support a dazzling array of marine life.
Describe everything about Guyots
Flat-topped seamounts; wave erosion has flattened them.
Describe everything about Mid-Ocean ridges
An area where the earth’s plates are separating.
Rift Valley: steep sided central valley.
Longest ridge is the mid-Atlantic ridge.
Fastest ridge is the East Pacific Rise.
LMFE
MS
Describe everything about Rift Zones
In the center of the highest part of the mid-ocean ridge is a narrow trench called a rift.
An area of frequent earthquakes- divergent plate boundary.
Slides are steep down to abyssal plain/ deep ocean floor. RED
Describe everything about Trenches.
There are many steep-sided canyons and deep, narrow valleys in the bottom of the ocean.
Occur where two plates converge; denser plate sinks.
Ocean trenches are the deepest part of the ocean basin and are deeper than any valley found on land.
Trenches are found in areas in the Pacific called the rings of fire where there’s a lot of volcanic activity and earthquakes. TC
_____ of the US is underwater.
50%
Early mariners believed that oceans were large, featureless _____ or _____ in the earth’s crust. s we have seen there are huge underwater mountain ranges (_____), great canyons (_____) and deep valleys (_____). Early depth measurements (_____) allowed surveys to determine the depth of the water in fathoms (the length between a person’s fully outstretched hands-6 ft).
Depressions-Basins-Mid Atlantic Ridge-Monterey Canyon- Mariana Trench-Soundings.
Define Hydrography
Is defined as the science that measures and describes the physical features of bodies of water and the land areas adjacent to those bodies of water.
Sound waves use _____ to move through gases, liquids, and solids.
Pressure
How do light and sound travel in water and air?
In water, sound travels faster and more than light; the reverse is true in the air.
Describe everything about sound.
Light cannot be used —> absorbed by water very quickly; usually lighting no further than 30 meters.
In air, sound moves at around 340 meters per second but in seawater, is zooms along at around 1500 meters per second.
