Reefs Sentence Examples

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.

Its coast, unlike that of the other islands of the archipelago, has few coral reefs.

In the dry season, however, it is obstructed by reefs, sandbanks, shallows, snags, trees and floating timber from the "Apostadero" up, so that even canoes find its ascent difficult, while savage hordes along its banks add to the dangers to be encountered.

Curacao consists of eruptive rocks, chiefly diorite and diabase, and is surrounded by coral reefs.

The head of the bay is fringed with islands and reefs, behind which is the mouth of the Santiago river, Poza Harbour, San Lorenzo Bay, Pailon basin and a network of navigable channels, all of which are difficult of access.

Few seas are more prolific in fish than the Persian Gulf and the Gulf of Oman; the great proportion of known species are edible and many have a commercial value for the isinglass or oil Shelly conglomerates and dead coral reefs of the littoral; red sandhills of the coast of Trucial Oman; alluvium of Turkish Iraq; river and lake deposits of Oman and the interior of Persia.

The surrounding seas contain great numbers of fish; the coral reefs abound with a great variety of molluscs; and there are numerous land-shells.

The reefs were left untouched till 1897, when an American company, which had obtained a concession in Phyong-an Do in 1895, introduced the latest mining appliances, and raised the declared export of 1898 to 240,047 pounds, believed to represent a yield for that year of 600,000 pounds.

Elsewhere the surface movements at least are controlled by the prevailing winds, which give rise in places to complex "transverse" currents, and near the coast are modified by the channels enclosed by the coral reefs.

The other islands are comparatively small, and may, in some cases, be regarded as detached parts of Roatan, with which they are connected by reefs.

A number of gold reefs intersect the surrounding district and in some of the reefs gold is mined.

There are, moreover, some rich gold quartz reefs in the neighbourhood.

The oyster being sedentary, except for a few days in the earliest stages of its existence, is easily exterminated in any given locality; since, although it may not be possible for the fishermen to rake up from the bottom every individual, wholesale methods of capture soon result in covering up or otherwise destroying the oyster banks or reefs, as the communities of oysters are technically termed.

A lighthouse has been erected at the entrance, but reefs render approach difficult, and the outer anchorage is fully exposed to west and north and not good holding.

The Araguaya has a course of 1080 m., considerable stretches of which are navigable for small river steamers, but as the river below Santa Anna Island is interrupted by reefs and rapids in two places - one having a fall of 85 ft.

The coast is very much indented, especially along the English Channel, and is rocky and lined with reefs and islets.

There are many rapids, caused by reefs of rock running across the bed, or by a sudden fall of from one to several feet, which produce very rough water below the swift glide; but the most dangerous places for navigation are where a point juts out into the stream, and the current, thrown back, causes a violent double backwater.

The entrance is contracted by Tiran and other islands, so that the passage is rendered somewhat difficult; and its navigation is dangerous on account of the numerous coral reefs, and the sudden squalls which sweep down from the adjacent mountains, many of which rise perpendicularly to a height of 2000 ft.

The slates of the Silurian have been bent into folds, and saddle reefs occur along the axis of the folds, as at Hargraves.

Numerous quartz reefs occur both in the Silurian and Ordovician rocks.

In these reefs the chief mineral is gold.

The sea around the Bahrein islands is shallow, so shallow as to admit only of the approach of native craft, and the harbour is closely shut in by reefs.

Except Bird and Denis islands, which are of coralline limestone, the Seychelles are of granite, with in places fringing reefs of coral based on granite foundations.

The lake is full of reefs, many just below the surface of the water, which is clear and very fresh.

Towards the centre, the Maldive, Chagos and Cocos groups are of characteristic coral formation, and coral reefs occur on most parts of the tropical coasts.

The junction of the great river Beni with the Madeira is at the Madeira Fall, a vast and grand display of reefs, whirlpools and boiling torrents.

The remainder of the Urubamba, as shown by Bosquet in 1806 and Castelnau in 1846, is interrupted by cascades, reefs and numberless other obstacles to navigation.

Barred by reefs, and full of rapids and impetuous currents, it cannot become a commercial avenue.

They are full of rapids and reefs.

But just before reaching the Uaupes there is a long series of reefs, over which it violently flows in cataracts, rapids and whirlpools.

The Coca river may be penetrated as far up as its middle course, where it is jammed between two mountain walls, in a deep canyon, along which it dashes over high falls and numerous reefs.

The islands number over eighty, and are interspersed with reefs.

The structure of coral animals (sometimes erroneously termed "coral insects") is dealt with in the articles cited above; for the distribution and formation of reefs see Coral-Reefs.

The Algerian reefs are divided into ten portions, of which only one is fished annually - ten years being considered sufficient for the proper growth of the coral.

The object of their visits was the investigation of the fauna and flora of the atoll, more especially of the formation of the coral reefs.

The coasts are in some parts precipitous; in others the mountains recede inland, and the coast is flat and bordered by coral reefs.

The common dead are buried or exposed to sharks on the reefs; bodies of chiefs are exposed in the fork of a tree.

The islands were discovered by the Dutch in 1616, and visited in 1767 by Philip Carteret; but no landing seems to have been effected, owing to the surrounding reefs, until the arrival of the "Challenger" in 1875.

Grand Cayman, a rock-bound island protected by coral reefs, is 17 m.

The islands though numerous are not as in Scotland and Norway a dominant feature of the coast, being generally small and often mere clusters of reefs.

Along two-thirds of its eastern side the coast is almost a straight line, without any inlet, Tamatave, the chief port on this side of the island, being only protected by coral reefs.

Throughout this distance the river is a hopeless labyrinth of rocks, islands, reefs and rapids.

The coral reefs fringing the coast are here broken by a straight channel with deep water giving access to the harbour, which consists of a series of natural channels and basins.

The Florida Keys are known for their spectacular coral reefs, excellent marina facilities and quiet restful anchorages.

Blast the pirates with a full broadside from your cannons to earn extra points, or lure them onto the reefs to destroy them.

Most modern reefs are built by corals and algae, but sponges, bryozoans and bivalves have all formed reefs in the geological past.

They are often seen in and around the deep, cold-water coral reefs west of Norway and Britain.

By 1997 27% of the world's coral reefs had been lost.

Additionally, most of the islands are made up of surrounding coral reefs and lagoons, just superb for snorkeling and diving activities.

Renowned for having the most exquisite coral reefs in the world and a refuge to rare marine life.

The island is surrounded by colorful coral reefs, hence the name Coral Island.

My guide - Itay - escorted me around stunning coral reefs teeming with tropical fish that glimmered brightly in the clear blue water.

The three-spot damselfish is a territorial herbivorous species common to Caribbean reefs.

A gale apprehensive took in and furled the Royals and top gallants and also a couple of reefs in top sails.

Many species of shark can be seen, including hammerheads, silkies, gray reefs and oceanic white-tips.

The reefs are composed of finger corals and brain corals covered with colorful sponges, hydroids, sea whips and sea fans.

The reefs are teeming with colorful tropical fish such as angel, butterfly, surgeonfish and graceful moorish idols.

Three reefs in the main, and a small jib made us fly into the increasing waves.

The forecast was giving lots of Easterly so we housed the topmast, put in two reefs and set the storm jib.

We visit rocky reefs and the vast beds of waving kelp which are home to hundreds of species.

Coral reefs are irresistible magnets to many varieties of fish and support a huge amount of marine life.

The East coast is marked by fine coral reefs, whilst the west coast offers dramatic drift diving through granite outcrops.

It has a diameter of some 40 miles with over 700 shallow patch reefs in its interior.

The Islands The Islands are a number of shallow reefs and coral pinnacles with deeper sandy gulleys between them.

There are rocky caves and reefs, massive sandbanks and vast gravel plains, each with their own range of wildlife.

Compared with coral reefs, vast swathes of the ocean appeared to be devoid of life.

Below the sea surface, kelp forests, sea caves, and rocky reefs are found, all supporting a wealth of marine life.

These reefs are home to sea horses, frog fish, giant sand eels and many other marine creatures.

Take scuba diving lessons around coral reefs, get your PADI open water scuba diving certification, or take advanced scuba diving classes.

If you enjoy scuba diving or snorkeling, Fiji travel provides plenty of opportunity to do so and is renowned for its coral reefs.

These rocky reefs provide shelter for a tremendous variety of marine animals and plants and make an excellent place to study the seashore.

For another, the conference was supposed to be about the carbonate sedimentology of reefs.

The most surprising sighting was a European shag Phalacrocorax aristotelis swimming past the reefs.

Marine Life There are several reefs scattered around with urchins, sponges, starfish, octopus qnd many species of reef fish.

Squid triggerfish tangs passed us on great coral reefs.

The underwater visibility on some of these reefs has to be seen to be believed, sometimes reaching 60 meters plus.

They can range from colorful reefs to large pelagic species and from cave systems to sunken wrecks.

Coral fishing, which fell off between 1889 and 1892 on account of the temporary closing of the Sciacca coral reefs has greatly decreased since 1884, when the fisheries produced 643 tons,-whereas in 1902 they only produced 225 tons.

The islands, inclusive of rocks and reefs, exceed loo in number and have a total area of 650o sq.

Finally you arrive in Aqaba, on the shores of the Red Sea, and have an opportunity to snorkel over colorful coral reefs.

The coastline is rugged, with treacherous reefs stretching far out to sea to wreck unwary ships.

The family spent their vacation scuba diving in many different abysses and reefs.

Increased acidity has a detrimental effect on the living coral reefs, as well as shelled creatures.

As the ocean continues to become more acidic because of carbon dioxide emissions, coral reefs are becoming decimated.

If the water temperature increases by as little as three to four degrees, scientists estimate that as much as ninety-seven percent of the world's coral reefs will be wiped out.

Coral reefs are a delicate eco-system found in the warm waters near the equator.

If you constantly marvel at stunning shots taken of rainbow colored fish darting around exquisite coral reefs, you might have wondered what equipment is used for underwater photography.

Whether you are interested in sun-drenched beaches, vibrant tropical reefs, exclusive shopping, or unique cultural venues, western Caribbean cruises offer something for every passenger.

Other options include snorkeling through spectacular coral reefs, embarking on a deep-sea fishing expedition or swimming with dolphins.

It offers white sand beaches, clean water and coral reefs.

Eco-burials that occur in the ocean are currently only performed by Eternal Reefs, Inc. This company uses the cremated remains of individuals and mixes it with cement.

The cement mixture is then used to create artificial reefs.

It is believed that this type of reef will help with the recovery of reefs that have been decimated by pollution.

The black, blue and pale green colors will blend beautifully while you are swimming among coral reefs or catching a wave.

This beautiful towel elegantly captures two dolphins swimming in a calm sea of blue, high above an abundance of colorful coral reefs and sea flowers.

Scientists know that damaged coral reefs due to pollution or climate changes spell trouble for the local marine population.

Removing major portions of coral reefs to make supplements would end up hurting marine life more than it would help people.

In these settings, the family can enjoy seeing specimen such as coral reefs, octopuses, exotic fish, sea urchins, starfish, jellyfish, sea turtles, seaweed, kelp, and mollusks.

Cozumel Reefs National Park, a 30,000 acre protected reserve at the southern end of the island, contains approximately 85 percent of the island's dive sites.

Tropical scene setter themes include island beaches, coral reefs, and bamboo or thatch hut patterns.

The lodes occur in Silurian metamorphic micaceous schists, intruded by granite, porphyry and diorite, and traversed by numerous quartz reefs, some of which are gold-bearing.

The Sciacca reefs were again closed for three winters by a decree of 1904.

The coasts are fairly indented, and, protected by these reefs, which often support a chain of green islets, afford many good harbours and safe anchorages.

Barrier reefs are rare; fringing reefs are numerous, except on the east side, which is nearly free, and there are many small isolated reefs and volcanic banks among the islands.

Desis lives invariably between tide-marks upon the rocks and coral reefs, and may be found at low tide either crawling about upon them or swimming in tidal pools and feeding upon small fish or crustaceans.

Along much of the western coast and along nearly the whole of the eastern coast extends a line of sand reefs and narrow islands, enclosing shallow and narrow bodies of water, such as Indian river and Lake Worth - called rivers, lakes, lagoons, bays and harbours.

On account of its sand reefs, the east coast has not so many harbours as the west coast.

It issues from the south-west corner of Lake Ladoga in two channels, which are obstructed by sandstone reefs, so that the better of the two has a depth of only 7 to 16 ft.

The coast line, including larger bays, but excluding reefs, islets, keys and all minute sinuosities, is about 2500 m.

They contain corals, but are not coral reefs.

It is the centre of an important gold-field, the reefs of which improve at the lower depths, the deepest shaft on the field being 2558 ft.

The coral reefs are of especial interest from their bearing on the general question of the formation of coral reefs.

Coral reefs remove calcium from solution in the sea on a vast scale.

It is not at all certain that the masses on which coral reefs are built consist entirely of the remains of the skeletons of reef-forming organisms and it is probable that chemically precipitated carbonate of lime predominates.

Such material, it is suspected, may form the massive bases on which barrier or fringing or atoll reefs are built up.

Interesting speculations as to the periods of origin of great coral reefs have been made by Wayland Vaughan, Andrews and Daly and Humphreys.

In Pleistocene times, then, when there were prolonged glacial ages, the sea-level was lowered and at the same time there was a reduction in sea temperature, so that the rate of reproduction of the coral polypes, and so the growth of reefs, was diminished.

Corals would now grow luxuriantly in these shallow coastal waters of increasing temperature, forming reefs and extensive coral flats.

In so far as it depends on solution of calcareous rock the Semper-Murray theory of coral reefs is unsatisfactory.

The central plateau is a plain whose surface presents "rounded, flat-topped hills and low ridges and reefs of limestone," with narrow intervening valleys.

The Aughrabies or Hundred Falls, as they are called, are divided by ledges, reefs and islets, the last named often assuming fantastic shapes.

The remarkable " stone reefs " of the north-east coast are ancient beaches hardened by the infiltration of carbonate of lime.

They are quite distinct in their formation from the coral reefs of the same coast.

The others are either difficult of access, or are rendered practically useless by dangerous reefs, sand bars and shoals.

The principal gold-bearing reefs are found along the Witwatersrand (" The Rand ").

Other auriferous reefs are found all along the eastern escarpment of the Drakensberg and are worked in the De Kaap (Barberton) district, on the Swaziland frontier, in the Lydenburg district, in the Murchison Range and in other places in the Zoutpansberg.

The reefs are narrower than those of the Rand, and the, ore is usually very hard.

About this time gold reefs were discovered in the Zoutpansberg district near Marabastad, and a few gold seekers from Europe and Cape Colony began to prospect the northern portions of the Transvaal.

Besides these there are a number of small indentations, sheltered anchorages formed by islands and reefs like that of Puerto Cabello, and estuaries and also open roadsteads, like those of La Guaira and Carupano, which serve important ports.

Under favourable conditions mining may be conducted under the protection of a few yards of solid rock only, as in the submarine work for the removal of reefs in the harbours of San Francisco and New York.

There are two harbours,difficult of access owing to the number of reefs and sunken rocks.

It appears to consist in the main of a continuation of an axis of old schists and slates, with granite intrusions, and flanked by coastal plains with Cretaceous or Jurassic, and Miocene beds, with Pleistocene sands and reefs and volcanic rocks.

Many ships have been wrecked on the jagged reefs which fringe their base.

The greater elevations are for the most part formed of limestones, except in the south, where they are largely volcanic. The coasts of the Gulf of Akaba are steep, with numerous coral reefs on both sides.

Coral formations are abundant; immense reefs, both barrier and fringing, skirt both coasts, often enclosing wide channels between the reef and the land.

The reefs on the eastern side are the more extensive; they occur in places as much as 25 m.

As the ocean warms and becomes more acid, the reefs die off.

Gold is obtained chiefly from quartz reefs, but there are still some important alluvial deposits being worked.

The islands on the southern margin of the Louisiade Archipelago are raised coral reefs, but the majority are mountainous, rarely, however, exceeding 3000 ft.; all of them are richly forested, but of little agricultural value.

The material is largely calcareous, and has probably been derived from the disintegration of the reefs, and from the shells of animals living in the shallows.

If the reefs impede navigation they form some good harbours.