Subject: Origin of Reefs

Martine Berube (
Mon, 18 May 1998 11:35:59 +0200 (MET DST)

Dear Marla,
I don't know much about reefs. You made me go back to my marine ecology
textbook and here are what I found:

1- The fringing reefs are formed close inshore on rocky coastline by the
growth of corals and associated hydrozoans (stinging corals), alcyonarians
(soft corals) and calcareous corals.
2- The barrier reefs are separated from the land by a lagoon, usually formed
by coastal subsidence, during which only the seaward reef, by continued
upward growth, is able to maintain contact with the sea surface. 
3- Atolls are simply annular reefs formed round subsiding volcanic islands.

Have a good day!

At 12.18 PM 14-05-1998 -0700, you wrote:
>What is the origin of the following reefs:  1) Fringing  2) Barrier
>and   3) Atolls?
Martine Berube
Unit of Evolutionary Genetics
Department of Molecular Biology
Free University of Brussels (ULB)
CP 244
Bld du Triomphe
B-1050 Brussels, Belgium
Tel: +32 2 650 5427
Fax: +32 2 650 5421