Page 301 - Ultimate Visual Dictionary (DK)

THE OCEAN FLOOR

KEY DEEP-OCEAN FLOOR SEDIMENTS

Calcareous
ooze
Pelagic clay
Glacial
sediments
Siliceous
ooze
Terrigenous
sediments
Continental
margin
sediments
Metalliferous
muds
Major nodule
fields

DEVELOPMENT OF AN ATOLL
ECHO-SOUND PROFILE
OF OCEAN FLOOR Event mark indicates
synchronization of Volcanic
Sand wave survey equipment island Coral
grows on
Sea shoreline
level

Sand
wave
Minor oscillations
caused by ship’s Seabed
movement profile Lagoon FRINGING REEF Eroded
volcanic
Coral continues island
to grow, forming subsides
barrier reef
Mid-ocean
ridge Velocity of sound in Reference code
water (4,898 ft∕sec;
1,493 m∕sec)
BARRIER REEF
Coral continues Lagoon
Ocean to grow where
trench waves bring food
Dead
coral

Volcanic island ATOLL
becomes submerged Coral
submerged
too deeply
to grow

Magma Sediment Volcanic island SUBMERGED ATOLL
(molten rock) is submerged
farther

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