Exploration of the Ocean Oceanography: Oceanographers: study the ocean & its floor up to 6.4 km into the ocean floor Ocean floor: is made up of continental.

The Marine Environment

Exploration of the OceanOceanography:

Oceanographers: study the ocean & its floor up to 6.4 km into the ocean floorOcean floor: is made up of continental & oceanic

crustSubmersibles: underwater research vessels

Help oceanographers study the ocean depthsBathysphere: early type of submersible used

for deep-ocean diving Remained connected to the research ship for

communication & life support

SubmersiblesBathyscaph: self-propelled, free-moving

submarine used for deep-ocean divingCan hold one pilot & 2 scientistsHas made new discoveries where life was

thought to be non-existantRobot submersibles: enable oceanographers

to study the ocean at great depths & long periods of time

SONAR: SOund Navigation And RangingAid in mapping the ocean floorConsists of transmitter & receiverSound waves are sent out, bounce off

ocean floor & are reflected back to receiver

SONAR

Features of the Ocean Floor1. Continental Margins: shallower portions of

the ocean floor with thick wedge of sediments

a) Continental Shelf: shallow water at the edge of continents & ocean boundary

Affected by the rise & fall of sea level

b) Continental Slope: steeper slope of the seaward edge of a continental shelf

Boundary between continental & oceanic crusts Submarine Canyon: feature carved into

continental slope by fast moving currents

Continental Margin

Features of the Ocean Floor2. Deep Ocean Basin: oceanic crust with a thin layer

of sedimenta) Trenches: long, narrow deepest features on Earth’s

surface b) Abyssal Plain: extremely vast flat areas where the

ocean depth is greater than 4 km Covers about ½ the deep ocean basin

c) Mid-Ocean Ridges: continuous series of underwater mountain ranges that run along the ocean floors

Form when plates pull away from each other

d) Sea Mounts: submerged volcanic mountains at least 1000 m high

General associated with hot spots If above earth’s surface they form islands (Hawaii) Guyot/Tablemount: volcanic mountain with a flat top

Deep Ocean Basins

Shoreline FeaturesBeach: Area in which

sediment is deposited along the shoreBeaches and shorelines are

constantly undergoing changes as waves and currents act on them

Formation beaches and their features is caused by wave refraction: the bending of waves when they reach shallow water

Features of depositional shoresSpitTomboloBarrier island

Figure 10-7

Depositional FeaturesSpit: long narrow accumulation of sand with

one end attached to the land and the other extending into the sea

Tombolo: an island is attached to the mainland by a narrow piece of land such as a spit

Barrier Island: long ridge of sand or other sediment deposited or shaped by currents separated from mainland

Barrier island, New Jersey

Figure 10-9c

Features of erosional shoresHeadlandSea archSea stack

Figure 10-4

Erosional FeaturesHeadland: land, high and

with a sheer drop, that extends out into a body of water

Sea Arch: opening eroded out of a cliff face

Sea Stack: blocks of rock isolated from the land by sea. Sea stacks begin as part of a headland. Erosion by waves erodes the softer, weaker parts of a rock first, leaving harder, more resistant rock behind

Sea stack and sea arch, Oregon

Protective StructuresSeawalls: built

parallel to shoreGroins & Jetties:

wall like structures built into the water perpendicular to the shoreline in order to trap beach sand

Breakwaters: built parallel to shoreline in water in front of beach

Ocean Resources1. Fresh water

a) Needed throughout the worldb) Possible to make through distillation,

freezing, & reverse osmosis

2. Mineralsa) Nodules taken from deep ocean for making

steel & other resourcesb) Petroleum is the most valuable mineral taken

from ocean

Ocean Resources3. Food

a) Aquaculture: farming of the oceanb) Now restricted into zones for farming, fishing,

recreation, & no touch-no take

4. Ocean-Water Pollutiona) Becoming more dangerous as we use harsh

chemicals & dump them into the oceanb) BP oil spill controversy estimated between 90-

180 million gallons of oilc) Plastic bottles and bags in oceans