In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water (six fathoms or less beneath low water).

Many reefs result from abiotic processes—deposition of sand, wave erosion planning down rock outcrops, and other natural processes—but the best-known reefs are the coral reefs of tropical waters developed through biotic processes dominated by corals and calcareous algae. Artificial reefs such as shipwrecks are sometimes created to enhance physical complexity on generally featureless sand bottoms in order to attract a diverse assemblage of organisms, especially fish.

Read more about Reef:  Biotic Reef

Other articles related to "reef, reefs":

Blue Reef Aquarium Portsmouth
1.0928095°W / 50.7801159 -1.0928095 Blue Reef Aquarium Portsmouth is an aquarium situated on Clarence Esplanade, Southsea, Portsmouth, England ... an underwater walkthrough tunnel offers close encounters with reef fish ... In 2007 the aquarium opened the Blue Reef Beach Club ...
Geologic Reef - Geologic Reef Structures
... Ancient reefs buried within stratigraphic sections are of considerable interest to geologists because they provide paleo-environmental information about the ... In addition, reef structures within a sequence of sedimentary rocks provide a discontinuity which may serve as a trap or conduit for fossil fuels or ... including some major extinct groups Rugosa and Tabulata, have been important reef builders through much of the Phanerozoic since the Ordovician Period ...
Aquarium Lighting - Marine - Reef
... The lighting used for reef aquariums is the highest intensity of all aquarium types ... Lamp colour plays an important role in reef aquarium lighting for both aesthetic preference and to optimally sustain the photosynthetic life within the ... Another light source in reef aquariums today is metal halide lighting ...
Blue Reef Aquarium - Hastings
0°35′46″E / 50.8559909°N 0.5961998°E / 50.8559909 0.5961998 Blue Reef Aquarium Hastings is an aquarium in Hastings, England which opened on 21 ... From the hidden world of UK waters, Blue Reef transports visitors to the spectacular ‘underwater gardens’ of the Mediterranean and the stunning beauty of tropical waters home to ... The centrepiece of the aquarium is the coral reef housed within a large ocean display with its underwater walkthrough tunnel ...
Pocklington Reef
... / 10.81222°S 155.73833°E / -10.81222 155.73833 Pocklington Reef is a coral reef and a mostly submerged atoll in the far southeast of Papua New Guinea ... the closest island, Loa Boloba, which is a tiny coral islet within the fringing reef near Cape Deliverance, the south east point of Rossel Island (Yela) in ... Pocklington Reef sits on top of Pocklington Ridge, which extends northeast from Rossel Island ...

Famous quotes containing the word reef:

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    Ralph Waldo Emerson (1803–1882)

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    Aeschylus (525–456 B.C.)