REPORTING SUMMARY
CORAL REEFS
 Located at Pacific Ocean and Carribean Sea
 Atolls –discontinuous ring-shaped reefs, enclosing more or less circular lagoons
 Corals are coral polyps (anemones) or animals, whereas nullipore algae are plants
 Their secretions mostly consists of calcium carbone
 The central part of the reef is primarily composed of cemented skeletal remains that by
gradual solution and recrystallization become limestone.
 Materials of engineering value obtained from coral reefs are:
1. coral – composed of skeletons with some sand and clay,
2. limestone & limestone sands
3. cascajo – generally in fragments with mixture of clay and loam