Coral-islands Sentence Examples
They are coral islands of comparatively recent elevation, and in no place rise more than 250 ft.
Oceanic islands are divided according to their geological character into volcanic islands and those of organic origin, including coral islands.
Next to these come the coral islands Nomuka and Lifuka in the Hapai group; Tofua, 2846 ft., Late or Lette, 1800 ft.
In the region of tropical hurricanes the navies, while in the Mediterranean and in the Indian Ocean converging wind system of a circular storm causes a heaping many soundings were made in connexion with submarine up of water capable of devastating the low coral islands of the cables to the East.
Pure calcareous sand and calcareous mud are formed by wave action on the shores of coral islands where the only material available is coral and the accompanying calcareous algae, crustacea, molluscs and other organisms secreting carbonate of lime.Advertisement
Recent limestones are being produced in this way and also in some places by the precipitation of calcium carbonate by sodium or ammonium carbonate which has been carried into the sea or formed by organisms. The precipitated carbonate may agglomerate on mineral or organic grains which serve as nuclei, or it may form a sheet of hard deposit on the bottom as occurs in the Red Sea, off Florida, and round many coral islands in the Pacific. Only the sand and the finest-grained sediments of the shore zone are carried outwards over the continental shelf by the tides or by the reaction-currents along the bottom set up by on-shore winds.
Here the broad distinction has been drawn between volcanic and coral islands; but this requires amplification, both because the coral islands follow more than one type, and because the work of corals is in many cases associated with the volcanic islands in the form of fringing or barrier reefs.
The coral islands are generally of the form well known under the name of atoll, rising but slightly above sea-level, flat, and generally of annular form, enclosing a lagoon.
In considering the flora of the islands it is necessary to distinguish between the rich vegetation of the fertile volcanic islands and the poor vegetation of the coral islands.
The low coral islands suffer frequently from drought; their soil is sandy and unproductive, and in some cases the natives attempt cultivation by excavating trenches and fertilizing them with vegetable and other refuse.Advertisement
It may, however, be that, moving among small coral islands for scores of generations and thus without materials, they lost the art.
The forests of the coast belt resembled those of the coral islands of the neighbouring parts of the Indian Ocean.
Heliopora coerulea is found between tide-marks on the shore platforms of coral islands.
Near volcanoes they contain many volcanic minerals, and around coral islands they are often in large part calcareous.
Idyllic palm-fringed coral islands set in the crystal-clear turquoise waters of the Caribbean Sea.Advertisement
The littoral vegetation of coral islands is derived from sea-borne fruits.
The various minor groups to the north of these (Ellice, Phoenix, Union, Manihiki and the America Islands) are coral islands.
They honeymooned in Maldives, a remote archipelago of coral islands in the Indian Ocean with baby Suri in tow.