Download THE Neritic zone and open ocean

Oceans
Two zones
• Neritic Zone~ is the part of the ocean that extends
from the low tide line to the edge of the continental
shelf.
• Open-Ocean Zone~ is beyond the edge of the
continental shelf
Ocean as A Natural Resource
• Provides food
• Fishing provides about 16% of worlds protein
• Travel
• Shipping
• Recreation
• Mined for minerals
• Examples: gold, diamonds, silver
• Drilled for oil
• Removes Carbon
• Provides Oxygen
• Source of biomedical organisms with potential for fighting
disease
Studying the Ocean
 Scientist once though that life couldn’t exist on the
deep floor.
 In 1977, scientists diving in Alvin to the Galapagos Rift
discovered a new community of organisms.
 These organisms can withstand tremendous pressure,
high temperatures, utter darkness, and toxic
chemicals.
 They are called extremophiles because of their
extreme living conditions.
Hydrothermal Vents
 Hydrothermal vents are is an area where ocean water sinks
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through cracks in the ocean floor, is heated by underlying
magma, and rises again through the cracks.
Hydrothermal vents are located along ocean ridges, where
the plates are moving apart and new ocean floor is being
formed.
The water carries gases and minerals from the Earth’s
interior.
These chemical nutrients in the heated water support the
unique group of organisms in the hydrothermal vents
Bacteria feed directly on the chemicals that come through
the vents, like the algae at the surface, this bacteria forms the
base of the food chain.
https://www.youtube.com/watch?v=D69hGvCsWgA
Cold Seeps
 https://www.youtube.com/watch?v=QnLA1HyGahU
 Cold seeps are shallow areas on the ocean floor where gases
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penetrate through underlying rock and sediment layers
and emerge on the ocean bottom.
Gases Methane and Hydrogen Sulfide
Not necessarily cold but about the same temperature of the
surrounding water if not a little warmer. Shallow areas on
the ocean floor where gases filter through layers of rock
and sediment to form brine (salt) pools on the ocean floor
Form along areas of activity from plate tectonics
Hydrothermal vents are ‘hot’. Cold seeps were first found
in cooler waters, and thus their name of cold seep