Christine Barmwater, age 8, of Bartlesville, Okla., for her question:

WHAT IS THE FLOOR OF THE OCEAN LIKE?

Much like the land's surface, the floor of the ocean varies greatly with slopes, shelves, plains, hills and steep walled canyons. Ridge and seamount are two words used by oceanographers to describe the mountain like features underwater, and they also use the words basin and trench. Deeps is the word they use to describe places where the ocean floor drops far down.

The ocean floor's average depth is about 12,000 feet, with three spots winning honors for being the deepest: 35,640 feet for the Mariana Deep in the Pacific Ocean, 30,246 feet for the Milwaukee Deep in the Atlantic Ocean and 24,440 feet for the Sunda Trench in the Indian Ocean.

When you start down into the ocean, you quickly leave the light we know on land. The golden world is gone the minute you drop below the water level and all becomes pale green. At less than 50 feet below the surface the red rays of the sun are too faint to be seen, and a bit deeper all a yellow tints begin to vanish. The green takes on a bluish tone, grows dimmer and a chill sets in.

At a depth of 600 feet the green is gone and only a strange, translucent blue can be seen and a bit deeper the last rays of the sun cannot penetrate even slightly and you are in a world of total blackness.

Down in the blackness near the ocean's floor the deep sea fish have learned to cope. Some have brilliant head and taillights, like fireflies. Others are blind and have tentacles or fins that act like sensitive feelers.

There's no seaweed in the black depths of the ocean., so the.fish must feed upon one another or on minute sea life. Some fish have rapier teeth so long that their mouths cannot be closed. Others have hinged fangs that hold the prey.

Weird eels are also found on the black sea's ocean floor. They have small heads but their mouths are many times as large as their entire bodies. Their stomachs are so elastic and their jaws so easily unhinged that they can swallow and slowly digest fish two or three times larger than themselves.

The mysterious ocean floor beyond the reach of light also has many fish with no pigment that look like glass, with blood visibly circulating and the last meal that was swallowed clearly visible.

At great depths the ocean's temperature is 28 degrees, the freezing point of salt water, but the great pressure at that depth makes the formation of ice impossible.