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The epipelagic zone, mesopelagic zone, bathypelagic zone, abyssopelagic zone, and the hadalpelagic zone are the major marine life zones in the ocean.


The epipelagic zone, mesopelagic zone, bathypelagic zone, abyssopelagic zone, and the hadalpelagic zone are the major marine life zones. Each zone is characterized by depth, with the hadalpelagic zone being the deepest.


Epipelagic -Sunlight reaches this zone. Photosynthesis is possible, hence marine plant life is found at this depth as is most of the life in the ocean.

Mesopelagic - Some light reaches this zone but not enough for photosynthesis to occur. Many of the animals found in this zone have special adaptations for living in low light, such as the lantern fish.

Bathypelagic -No light reaches this depth. Giant squid and angler fish are found at this depth, and whales may dive this deep for prey.

Abyssopelagic -Even fewer animals live in this zone. By this depth, the temperature is close to freezing and the pressure is immense. Many animals are bioluminescent.

Hadalpelagic -Deep sea trenches are in the hadalpelagic zone. Animals may survive of the remains of other organisms which have fallen to the ocean floor. Some survive near hydrothermal vents.


Wind and ocean currents are nothing else than heat transfering agents.


What do you tink happens when you bring a pot of water to the boiling point? Those bubbles that rise from the bottom to the top transfer the heat from the burning flame (warming up the base of the pan) to the surface where the gas is liberated into air.

That vertical movement that is so easily seen in a transparent kettle, doesn't wait for the 100°C limit. It starts the minute that a difference of temperature sets in (for whatever reason) within the kettle.

That happens because warm water (or air) is lighter than cold water (or air); it is less dense. It therefore moves up and leaves space for the cold air to move in.


Therefore the Sun has a lot to do with air and water movements since it is at the origin of the temperature differences that can be measured (to make things simple) at the Equator and at the Poles.




Oxygen as a gas is made up of molecules that each are built from two atoms of the element oxygen, that is denoted by #O#.

There is another form of oxygen, known as ozone #O_3#, that has three oxygen atoms per molecule. Though highly poisonous, it is an essential part of the upper atmosphere (it stops dangerous UV rays).


Earth's four spheres are: the lithosphere , the atmosphere , the hydrosphere , and the biosphere .


Every thing on Earth can be placed in one of the four major subsystems or spheres.

The Lithosphere refers to the land mass which includes all forms of terrestrial structures and zones.

The Atmosphere refers to the blanket of air that covers the air which is itself divided into subspheres: the troposphere, the stratosphere, the mesosphere, and the thermosphere which contains the ionosphere and the exosphere.

The Hydrosphere refers to all water bodies, liquid and frozen (sometimes called the cryosphere), salt and fresh, surface or underground.

The Biosphere refers to all living creatures that exist.



The slower the igneous rocks form the larger the crystals that are formed. The igneous rocks that form on or near the surface cool quickly with small crystals.


Generally the granite that forms deep in the earth has large crystals. lava that reaches the surface and cools quickly has small crystals. Obsidian or volcanic glass cools so quickly that the crystals are so small that they can't be seen.


A magnitude 5 earthquake would be 100 times stronger than a magnitude 3 earthquake.


The Richter scale, used to measure earthquake magnitudes, is a base 10 logarithmic scale. This means that a magnitude 5 quake would be 10 times stronger than a magnitude 4 (10^1 power), and would be 100 times stronger than a magnitude 3 (10^2 power).

This estimate is only accurate using the Richter scale, and much more subjective measurements of earthquake power and energy output are calculated using more complex equations.

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