Word Finder - reefs

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A chain or range of rocks, sand, or coral lying at or near the surface of the water.

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A large vein of auriferous quartz; hence, any body of rock yielding valuable ore.

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A portion of a sail rolled and tied down to lessen the area exposed in a high wind.

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A reef knot.

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To take in part of a sail in order to adapt the size of the sail to the force of the wind.

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To pull or yank strongly, especially in relation to horse riding.

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(of paddles) To move the floats of a paddle wheel toward its center so that they will not dip so deeply.

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Reef the paddles.

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The itch; any eruptive skin disorder.

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Dandruff.

The Rand reefs, first mined in 1886, cover a large area.

They are apparently volcanic. Coral reefs lie off the coasts and render them difficult of access.

The formation is noted for its regularity as regards both the thickness and the gold-tenor of the ore-bearing reefs, in which respect it is unparalleled in the geology of the auriferous formations.

It is surrounded by coral reefs, and is richly wooded.

Round most of the islands there is a luxuriant coral growth; but, as the reefs lie at no great distance, and follow the line of the coast, the inter-island channels are comparatively safe.

No auriferous reefs have been found.

The discovery of alluvial gold in 1851 brought many immigrants to the district; but the opening up of the quartz reefs in 1872 was the principal factor in the importance of Bendigo.

This was a conservative estimate, and was made before the full extent of the reefs was known; in 1904 Lionel Phillips stated that the main reef series had been proved for 61 m., and he estimated the gold remaining to be mined to be worth £2,500,000,000.

In the Mwanza district are conglomerate reefs of great extent.

Its coasts are encircled with coral reefs, extending in some places 3 m.

Coral reefs protect the coasts in many parts; they are frequently interrupted, but the passages through them are often difficult of navigation.

These new structures would rest uncomfortably upon eroded formations and this, Wayland Vaughan points out, is what we actually observe in the case of living and fossil coral reefs.

To the north the reefs continue, marking the former extension of the land, for about 160 m., ending with the Huon Islands.

The coast-line is fringed with small islets and shoals and reefs, which make navigation dangerous.

The principal formation is coralline limestone; the eastern coast is defended by coral reefs, and the neighbouring sea (extending as far as New Guinea, and thus demonstrating a physical connexion with that land) is shallow, and abounds in coral in full growth.

Here the reefs are generally less perfect than elsewhere, seldom forming complete central lagoons, and as they were formerly exposed to the constant attacks of the Mopla pirates from India, the people are hardier and more vigorous than their less warlike southern neighbours.

Minikoi atoll, with the numerous wrecks on its reefs, its lighthouse, and its position on the track of all eastward-bound vessels, is a familiar sight to seafarers in these waters.

The Kevori grits, and the raised coral reefs are upper Cainozoic, and perhaps Pleistocene; but the reefs occur inland up to a height of 2000 ft.

The group, consisting of small islands and reefs (which mark the extreme northern range of the coral-building polyps), is of oval form, measuring 22 m.

Even the reefs are not wholly formed of coral.

As in other countries, however, the working of quartz reefs gradually compensated for this.

The Great Barrier Reef forms the prominent feature off the north-east coast of Australia; its extent from north to south is 1200 m., and it is therefore the greatest of all coral reefs.

Molybdenum, in the form of molybdenite (sulphide of molybdenum), is found in Queensland, New South Wales and Victoria, associated in the parent state with tin and bismuth in quartz reefs.

The northern horn of the bay is formed by Filey Brigg, a narrow and abrupt promontory, continued seaward by dangerous reefs.

The Squamipennes, or scaly-finned fishes, are principally found in the seas of southern Asia, and especially near coral reefs.

Johannesburg owes its existence to the discovery of gold in the Witwatersrand reefs.

Off the island, which was discovered by the Portuguese in the 1 5th century, are extensive and very dangerous reefs.

The alluvial gold-fields were the richest ever opened up, but as these deposits have become exhausted the quartz reefs at deep levels have been exploited, and several mines are worked at depths exceeding 2000 ft.

The shores are rocky, there are no harbours, and the roadstead off Grand Bourg is difficult of access, owing to the surrounding reefs.

The average depth varies from 1500 to 2500 fathoms, and from this level innumerable volcanic ridges and peaks rise almost or quite to the surface, their summits for the most part occupied by atolls and reefs of coral formation, while interspersed with these are depressions, mostly of small area, among which the deepest soundings recorded have been obtained.

In an area to be defined roughly as lying about the Tropic of Cancer, between Hawaii and the Bonin Islands, there are scattered a few small islands and reefs, of most of which the position, if not the existence, is doubtful.

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.

As to the distribution of coral reefs within the Pacific area, in Micronesia the northern Marianas (volcanic) are without reefs, which, however, are well developed in the south.

The Pelew islands have extensive reefs, and the Caroline, Marshall and Gilbert islands are almost entirely coral.

Of the Polynesian Islands, the Hawaiian chain presents the type of a volcanic group through which coral reefs are not equally distributed.

The main island of Hawaii and Maui at the east end are practically without reefs; which, however, are abundant farther west.

Round the volcanic Marquesas Islands, again, coral is scanty, but the Society Islands, Samoa and Tonga have extensive reefs.

The Loyalty Islands exhibit this type, in which former reefs appear as low cliffs, elevated above the sea, and separated from it by a level coastal tract.

For the much debated question as to the conditions under which atolls and reefs are formed, see Coral Reefs.

As to the local distribution of reefs, it has been maintained that in the case of active volcanic islands which have no reefs, their absence is due to subterranean heat.

Festschrift zum 70ten Geburtstage von Ernst Haeckel, 19(34) has restored the conditions existing in the lagoons and atoll reefs of the Jurassic sea of Solnhofen in Bavaria; he has traced the process of gradual accumulation of the coral mud now constituting the fine lithographic stones in the inter-reef region, and has recognized the periodic laying bare of the mud surfaces thus formed; he has determined the winds which carried the dust particles from the not far distant land and brought the insects from the adjacent Jurassic forests.

Vera Cruz is an open anchorage inside a series of reefs which afford no protection to vessels from the " northers."

There are gold-bearing quartz reefs at Madibi, near Mafeking, where mining began in 1906.

The lakes were small at first, and each had its own outlet at the lowest depression in -the height of land to the south; but as the ice melted back, neighboring lakes became confluent at the level of the lowest outlet of the group; the outflowing streams grew in the same proportion and eroded a broad channel across the height of land and far down stream, while the lake waters built sand reefs or carved shore cliffs along their margin, and laid down sheets of clay on their floors.

The eastern coast is fringed by long-stretching sand reefs, enclosing lagoons so narrow and continuous that they are popularly called rivers.

The western coast has fewer and shorter off-shore reefs; much of it is of minutely irregular outline, which seems to be determined less by the work of the sea than by the forward growth of mangrove swamps in the shallow salt water.

It has a relatively rapid descent toward the inner lowland, and a very gradual descent to the coast prairies, which become very low, flat and marshy before dipping under the Gulf waters, where they are generally fringed by off-shore reefs.

Nearly all the rest of the coast is fringed by off-shore reefs, built up by waves from the very shallow sea bottom; in virtue of weak tides, the reefs continue in long unbroken stretches between the few inlets.

The Niagara limestone contains the oldest known coral reefs of the continent.

Barrier and fringing reefs, as well as atolls, occur in the group, but the channels between the islands are dangerous chiefly from the strong currents which set through them.