Volcanoes Sentence Examples
Extinct volcanoes are numerous in several of the ranges, e.g.
It is along the western side of the northern half of the chain that the line of volcanic action is apparent; the islands here (of which some are active volcanoes) are lofty.
In all these cases, however, the eruptions have now almost ceased; and the great volcanoes of the present day lie in the islands off the eastern and south-eastern coasts.
Finally in the east of Yezo rise the most westerly volcanoes of the Kurile chain.
On the Pacific slope extinct volcanoes (mentioned in Chinese annals) have been reported in the Ilkhuri-alin mountains in northern Manchuria.Advertisement
Since the Rev. William Ellis and a party of American missionaries first made the volcano known to the civilized ' Among the minqr phenomena of Hawaiian volcanoes are the delicate glassy fibres called Pele's hair by the Hawaiians, which are spun by the wind from the rising and falling drops of liquid lava, and blown over the edge or into the crevices of the crater.
All the volcanoes in the group were then quiescent.
Mineral Springs.The presence of so many active volcanoes is partially compensated by a wealth of mineral springs.
Volcanoes Fuji is the most remarkable volcanic peak.
The eastern ranges of the Bolivian Andes are formed of Palaeozoic rocks with granitic and other intrusions; the Western Cordillera consists chiefly of Jurassic and Cretaceous beds, together with the lavas and ashes of the great volcanoes; while the intervening plateau is covered by freshwater and terrestrial deposits through which rise ridges of Palaeozoic rock and of a series of red sandstones and gypsiferous marls of somewhat uncertain age (probably, in part at least, Cretaceous).Advertisement
In three of them the volcanoes are entirely extinct, while the fourth is still in great activity.
The existing volcanoes belong to four separate arcs or chains.
This part of Mexico is highly volcanic in character, the transverse ridge just described having a large number of extinct volcanoes and at least three (Colima, Jorullo and Ceboruco) that are either active or semi-active.
Farther north nearly the whole of the depression is filled with lavas, tuffs and agglomerates, derived from the Tertiary and recent volcanoes which form the most striking feature of the Andes of Ecuador.
There are twelve active volcanoes in the archipelago.Advertisement
There are eight other volcanoes, which although extinct or dormant have well-preserved cones.
With this possible exception there are no active volcanoes in Korea, and the region has also been remarkably free from earthquakes throughout historic times.
In Owen's Valley is a fine group of extinct or dormant volcanoes.
Along the south-eastern margin, in front of the Taurus, stands a line of great volcanoes, stretching from Kara-Dagh to Argaeus.
Then the country came once more under the sea, and the debris of the previous formations, mixed with fragments from the volcanoes then situated in West Finland, formed the so-called Bothnian series.Advertisement
A large part of the chain is covered by the products of the great volcanoes which still form the highest summits of the Chilean and Argentine Andes.
The recent lavas of the still active volcanoes of the south are olivine-bearing hypersthene-andesite and basalt.'
In Baluchistan these volcanoes appear to be extinct; though the Koh-i-Tafdan, beyond the Persian frontier, still emits vapours at frequent intervals.
The lavas and ashes which form these cones are mostly andesitic. Mud " volcanoes " occur upon the Makran coast, but it is doubtful whether these are in any way connected with true volcanic agencies.
Sulphur has long been worked on a small scale in the Koh-i-Sultan, the largest of the volcanoes of western Baluchistan.Advertisement
Nor should the evidences of active volcanic agency afforded by the mud volcanoes of the coast be overlooked.
The volcanoes of Bolivia lie almost entirely in the Western Cordillera - the great summits of the eastern range, such as Illimani and Sorata, being formed of Palaeozoic rocks with granitic and other intrusions.
Another chain of volcanoes runs from Ichinskaya (which burst into activity several times in the 18th and igth centuries) to Shiveluch, seemingly parallel to the above but farther north.
The two chains contain twelve active and twenty six extinct volcanoes, from 7000 to more than 15,000 ft.
The northern portion of the residency constitutes the most fertile portion, is generally flat with a hilly group in the middle, where the two inactive volcanoes, Karang and Pulosari, are found, while the north-western corner is occupied by the isolated Gede Mountain.
It seems to be a sublimation-product formed in volcanoes by the interaction of the vapour of ferric chloride and steam.
Raised shore-lines, occasional earthquakes, and slow measurable elevation of the land about active volcanoes, indicate that elevation is now in progress, but the geological evidence shows no sign of former submergence of a connecting isthmus.
In the Alaskan Range and the Aleutian Range there are more than a dozen live volcanoes, several of them remarkable; the latter range is composed largely of volcanic material.
Their only remarkable features are the volcanoes on the easterly islands, already mentioned.
The town of Shemakha, near the eastern end of the system, was the scene of volcanic outbreaks as late as 1859, 1872 and 1902; while in the adjacent peninsula of Apsheron mud volcanoes exist in large numbers.
The last phase in the history of the Caucasus was marked by the growth of the great volcanoes of Elbruz and Kasbek, which stand upon the old rocks of the central zone, and by the outflow of sheets of lava upon the sides of the chain.
There are no volcanoes.
Its centre is traversed from south-east to north-west by the Coiron range which extends from the Rhone to the Mont Mezenc (5755 ft.), the highest point in the department, and the oldest of its many volcanoes.
The Central is the axis of the system, is distinguished by a line of lofty volcanoes and paramos, some of which show their white mantles 2000 to 3000 ft.
Although volcanoes are by no means absent, they are much less important than in Ecuador, and their products take a far smaller share in the formation of the Andes.
The peaks of this system are much higher than those of the Coast Range, varying from 5000 to 11,000 ft., and the highest of them are cones of extinct volcanoes.
Oil has been discovered near the mud volcanoes of Minbu, but it seems to lie at too great a depth to be profitably worked.
The Napo rises on the flanks of the volcanoes of Antisana, Sincholagua and Cotopaxi.
There have been no active volcanoes since the Pliocene Tertiary time, but the country is still subject to dangerous earthquakes.
Mineral springs are common, especially near former volcanoes.
Above its surface tower a great number of volcanoes and several craters, and its waters are alive with water-fowl, a multitude of ducks of various species breeding on its islands.
Altogether 107 volcanoes are known to exist in Iceland, with thousands of craters, great and small.
They are grouped in dense masses round the volcanoes from which they have flowed, the bulk of the lava dating from outbreaks which occurred in prehistoric times.
Many of the Icelandic volcanoes during their periods of quiescence are covered with snow and ice.
At Myvatn there are several volcanoes, which were particularly active in the years 1724-1730.
There are often long intervals between the successive outbreaks, and many of the volcanoes (and this is especially true of the chains of craters) have only vented themselves in a solitary outburst.
The geysers and other hot springs are due to the same causes as the active volcanoes, and the earthquakes are probably manifestations of the same forces.
Some bright spots are visible by the earth-light when the moon is a thin crescent, which were supposed by Herschel to be volcanoes in eruption.
Most are of coral formation, but the hills of Manus are believed to be extinct volcanoes.
Another group of extinct volcanoes is in the Vakinankaratra district, S.W.
Here the volcanic action, which preceded the general upheaval of recent strata and the folding of the edges of the interior highlands, is still in evidence in occasional boiling mud volcanoes on the coast-line.
Evidence of extinct mud volcanoes exists through a very wide area in Baluchistan and Seistan.
Although, in the explored portion of the Fuegian chain, the volcanoes which have been mentioned from time to time have not been met with, there seem to have existed to the south, on the islands, many neo-volcanic rocks, some of which appear to be contemporaneous with the basaltic sheet that covers a part of eastern Patagonia.
The volcanoes of Lanin (12,140 ft.), Quetropillan (9180 ft.), Villarica (10,400 ft.), Yaimas and Tolhuaca are all more or less active; the first is in the main chain, while the others are on the western slope.
The western, which reaches an altitude of about io,000 ft., then ceases to exist as a continuous chain, there remaining only a short, high ridge, called by Edward Whymper the " Pacific range of the equator," and between this ridge and the crystalline Andean axis, the " avenue of volcanoes," to use his words, arises amidst majestic scenery.
Pichincha (15,804 ft.) and Cotocachi (16,297 ft.) are the loftiest volcanoes of the western range.
The volcanoes Campainero (12, 470 ft.) and Pasto (14,000 ft.) are also in that zone.
The great volcanoes, active and extinct, are not confined to any one zone.
Somewhat later Pliocene deposits in the Val d'Arno, as well as the tuffs associated with the Pliocene volcanoes in central France, yield plants of a more familiar type, a considerable proportion of them still living in the Mediterranean region, though some are only now found at distant localities, and others are extinct.
Near volcanoes they contain many volcanic minerals, and around coral islands they are often in large part calcareous.
These must either have been ejected by submarine volcanoes or drifted by the wind from active vents, as the fine ash discharged by Krakatoa was wafted over the whole globe.
Minahassa, the north-eastern extremity, consists of a plateau divided into sections by volcanoes (Klabat, 6620 ft., being the highest).
Eruptions still take place at intervals, but the volcanoes for the most part seem to have reached the solfataric stage.
The legends are thick in every culture, from floods to plagues to volcanoes and the ground rising up to swallow people, to the influence of men who slaughtered whole nations for entertainment.
Looking ahead toward the volcanoes on the Chilean altiplano.
Active volcanoes and vast lava deserts stand in direct opposition to utterly boundless glacial landscapes.
As the subducting oceanic crust melts as it goes deeper into the Earth, the newly-created magma rises to the surface and forms volcanoes.
Topics include tropical cyclones, volcanoes, burglary, AIDS. iii.
This amazing country is full of incredible landscapes featuring glaciers, hot springs, geysers, active volcanoes and vast lava deserts.
Pressure was building at the Earth's very core... Volcanoes, millions of years extinct, suddenly erupted into burning, gushing life.
The backbone of the country is the Andean highlands, made up of two mountainous chains and over 30 volcanoes.
Did you know that not all volcanoes erupt lava?
Active volcanoes, ice fluted pyramids and immense rock monoliths are just a few examples of what this fantastic continent has to offer.
Barnacles When you are exploring the seashore, you will notice the rocks are covered in small white volcanoes.
Shield volcanoes are low or almost flat, which makes them look like a big shield volcanoes are low or almost flat, which makes them look like a big shield.
The youngsters made their own volcanoes with bicarbonate soda and vinegar and found out about what happened in Montserrat.
They visit deep ocean volcanoes in research submersibles reaching depths four times greater than the most advanced submarines.
When the mists clear however the view across to the snow capped volcanoes of the mainland is stunning.
Shield volcanoes are low or almost flat, which makes them look like a big shield.
Within its borders are snow-capped mountains, smoking volcanoes, large rivers, lush tropical coastal plains and dense Amazonian jungle.
Some of the volcanoes of the western districts of Victoria have been in eruption probably subsequent to the advent of the black-fellow.
The atmosphere is a cause of disease in the neighborhood of chemical works, large towns, volcanoes, &c., in so far as it carrie, acid gases and poisons to the leaves and roots; but it is usual tc associate with it the action of excessive humidity which brings about those tender watery and more or less etiolated condition, which favor parasitic Fungi, and diminish transpiration and therefore nutrition.
The sixth book is devoted to the explanation, in accordance with natural causes, of some of the more abnormal phenomena, such as thunderstorms, volcanoes, earthquakes, &c., which are special causes of supernatural terrors.
North of the two first-mentioned volcanoes Lake Taupo spreads over 238 sq.
Halite may occur as a sublimate on lava, as at Vesuvius and some other volcanoes, where it is generally associated with potassium chloride; but its usual mode of occurrence is in bedded deposits, often lenticular, and sometimes of great thickness.
In 1788 he visited Vesuvius and the volcanoes of the Lipari Islands and Sicily, and embodied the results of his researches in a large work (Viaggi alle due Sicilie ed in alcune parti dell' Apennino), published four years later.
It is the accretion of countless eruptions from over twenty volcanoes, and covers an area of 1300 sq.m.
The main feeder of Albert Edward Nyanza, and western head-stream of the Nile, the Ruchuru, rises on the north side of the volcanoes north of Lake Kivu (see Mfumbiro).
Nicaragua boasts Caribbean islands, 19 smoldering volcanoes and beautiful, unspoiled beaches.
I could put on a show of force - Order volcanoes to spew out poison, Have tectonic plates tear them to shreds.
The seismic signals recorded around active volcanoes show a much greater variety than signals recorded in the vicinity of tectonic earthquakes.
A link is provided to the Smithsonian 's Global Volcanism Program for information on active volcanoes.
Some things you can find on topographic maps free online are volcanoes and earthquake fault lines, mountain ranges and deserts.
Not only does it boast miles of sun-drenched beaches, volcanoes and tropical forests, but the Caribbean also possesses a rich history and unique cultural diversity.
Will we be plagued with volcanoes becoming active, earthquakes shaking the globe and tidal waves flooding the planet, or will it be a spiritual transition?
Once he's mastered geography, broaden his knowledge and fancy his curiosity by exploring the world of volcanoes, earthquakes and other natural occurrences that have shaped both our planet and the continental plates.
It is home to Volcanoes National Park, which includes Kilauea, one of the world's most active volcanoes as well as Mauna Loa, the world's largest.
The most popular of the Big Island attractions, Volcanoes National Park, established in 1916, encompasses 377 square miles.
It includes Kilauea, one of the most active volcanoes in the world as well as Mauna Loa and Mauna Ulu.
Visitors can view exhibits about the volcanoes at the Kilauea visitors' Center and the Jagger Museum.
Maui, Kauai and the Big Island are better suited for travelers looking to explore Hawaii's natural gems, such as active volcanoes, lush rainforests, stunning sunsets, seaside cliffs, and pink, black and white sand beaches.
The Aloha State has something for everyone, from breathtaking beaches and active volcanoes to historical sites and dozens of award-winning golf courses.
Kids love the showmanship of the teppanyaki chefs, as they create smoking volcanoes, flip shrimp tail into their hats and expertly slice and dice ingredients.
Physically its continuity is broken by Monte Urticu and several smaller hills which rise within it, but these are all composed of volcanic rock and are the remains of Tertiary volcanoes.
In Tertiary times the Central Plateau was the theatre of great volcanic activity from the Miocene, to the Pleistocene periods, and many of the volcanoes remain as nearly perfect cones to the present day.
The number of main craters may be about twenty-five, but there are very many small eruptive cones on the flanks of the old volcanoes.
Among these are to be found a singularly large number of both active and inactive volcanoes, including the well-known Salak and Gede in the north, and bunched together at the eastern end the Chikorai, Papandayan, Wayang, Malabar, Guntur, &c., ranging from 6000 to 10,000 ft.
All the other lakes of Central Italy, which are scattered through the volcanic districts west of the Apennines, are of an entirely difierent formation, and occupy deep cup-shaped hollows, which have undoubtedly at one time formed the craters of extinct volcanoes.
A number of small extinct volcanoes, however, appear in all directions.
Free or native sulphur, known also as "virgin sulphur," occurs in connexion with volcanoes and in certain stratified rocks in several modes, viz.
The dioxide has been known since the earliest times and is found as a naturally occurring product in the gaseous exhalations of volcanoes and in solution in some volcanic springs.
The highest volcanoes, Tabanan, Batur and Gunung Agung (Bali Beak), have respectively heights of 7545 ft., 73 8 3 ft., and 10,497 ft., the central chain having an average altitude of 3282 ft.
Mud volcanoes occur at Minbu, but they are not in any sense mountains, resembling rather the hot springs which are found in many parts of Burma.
Whether the mud " volcanoes" of the Irrawaddy valley have any connexion with volcanic activity may be doubted.
Forbes was also interested in geology, and published memoirs on the thermal springs of the Pyrenees, on the extinct volcanoes of the Vivarais (Ardeche), on the geology of the Cuchullin and Eildon hills, &c. In addition to about 150 scientific papers, he wrote Travels through the Alps of Savoy and Other Parts of the Pennine Chain, with Observations on the Phenomena of Glaciers (1843); Norway and its Glaciers (1853); Occasional Papers on the Theory of Glaciers (1859); A Tour of Mont Blanc and Monte Rosa (1855).
But generally these volcanoes are quiescent.
But he and his colleagues were now, in Disraelitish phrase, " exhausted volcanoes."
The lavas and ashes ejected by these volcanoes consist of liparite, dacite, andesite and basalt.
But the foundation on which the volcanoes rest is exposed along the east coast of Hondo (in the Kwanto, Abukuma and Kitakami hills), and also in the island of Yezo.
They are considered to be volcanoes, and the mountains of the neighbouring Uliasser islands the remains of volcanoes.
Volcanic dust thrown into the air settles out slowly, and some of the products of submarine and littoral volcanoes, like pumice-stone, possess a remarkable power of floating and may drift into any part of the ocean before they become waterlogged and sink.
The peaks of the Guatemala Cordillera rise round it, culminating near its southern end in the volcanoes of San Pedro (7000 ft.) and Atitlan (11,719 ft.).
Fine lakes and waterfalls, innumerable pools, in temperature from boiling-point to cold, geysers, solfataras, fumaroles and mud volcanoes still attract tourists in large numbers.
Nothing in the general physiognomy of the islands is more remarkable than the number and distribution of the volcanoes, active or extinct.
Iii north-western Wyoming there are extensive and heavy lava sheets, uplifted and dissected, and crowned with a few dissected volcanoes.
The Cascade Range is in essence a maturely dissected highland, composed in part of upwarped Colombian lavas, in part of older rocks, and crowned with several dissected volcanoes, of which the chief are (beginning in the north) Mts Baker (Io,827 ft.), Rainier (14,363 ft.), Adams (12,470 ft.) and Hood (11,225 ft.); the first three in \Vashington, the last in northern Oregon- These bear snowfields and glaciers; while the dissected highlands, with ridges of very irregular arrangement, are everywhere sculptured in a fashion that strongly suggests the work of numerous local Pleistocene glaciers as an important supplement to preglacial erosion.
Bougainville, the largest of the group, contains Mt Balbi (10,170 ft.), and two active volcanoes.
Cinder cones and tufa cones abound, but one of the most distinguishing features of the Hawaiian volcanoes is the great number of craters of the engulfment type, i.e.
Another curious feature of Mauna Loa, and to some extent of other Hawaiian volcanoes, is the great number of caves, some of them as much as 60 to 80 ft.
Though less superstitious than the Tahitians, the idolatry of the Sandwich Islanders was equally barbarous and sanguinary, as, in addition to the chief objects of worship included in the mythology of the other islands, the supernatural beings supposed to reside in the volcanoes and direct the action of subterranean fires rendered the gods objects of peculiar terror.
Human sacrifices were slain on several occasions, and vast offerings presented to the spirits supposed to preside over the volcanoes, especially during the periods of actual eruptions.
Most of the islands are mountainous, with still active volcanoes.
The great chain of volcanoes which runs through Sumatra and Java is continued eastwards into the Moluccas, and terminates in a hooklike curve which passes through the Damar Islands to the Banda group. Outside this hook lies a concentric arc of non-volcanic islands, including Tenimber, the Lesser Kei Islands, Ceram and Buru; and beyond is still a third concentric arc extending from Taliabu to the Greater Kei Islands.
Upon the floor of older rock rise a number of volcanoes, some of which are now extinct while others are still active.
Bonvalot noted some extinct volcanoes in the northern Tibet desert.
Aluminium sulphate Al(S04)3, occurs in the mineral kingdom as keramohalite, Al 2 (SO 4) 3.1811 2 0, found near volcanoes and in alum-shale; aluminite or websterite is a basic salt, Al 2 (SO 4) (OH)4.71120.
The volcanoes have long been extinct, but the diminished energy now causes hot springs and geysers in all parts of the plateau, about loo in number.
In North America, the principal region of volcanic activity lay in the west; great thicknesses of igneous rocks occur in the Lower Carboniferous rocks of British Columbia, and from the middle of the period until near its close volcanoes were active from Alaska to California.
The mountainous regions contain numerous lakes, many evidently occupying the craters of extinct volcanoes.
On the south and south-east the valley is bounded by two volcanoes, Lubuk Raja and Si Buwal Buwali, whence were derived the volcanic tuffs of the valley and of the plateau of Sipirok, with their lakes, which are drained by the Batang Toru and its affluents.
To the north of the volcanoes, which rise to 9500 ft.
South of the volcanoes the northern affluents of the Ombilin - Sumpur, Sello and Sinamar - flow through valleys parallel to one another in a north-west to south-east direction.
Generally the lower valleys of the rivers lie at elevations of 600 to woo ft.; higher up they rise to 2500 or 3000 ft.; the mountain chains rise to 5500 ft.; the volcanoes tower up from 6500 to nearly ro,000 ft.
Besides a valuable account of the principal sacred sites of Judaea, Samaria and Galilee as they existed in the 7th century, he also gives important information as to Alexandria and Constantinople, briefly describes Damascus and Tyre, the Nile and the Lipari volcanoes, and refers to the caliph Moawiya I .
The northern part of the mountain chain of the northern peninsula is volcanic, its volcanoes continuing the line of those of Makian, Ternate and Tidore.
In the south, the older beds disappear and the whole chain is formed chiefly of Cretaceous beds, though Eocene and probably Jurassic rocks are Medit Er R Anean Plutonic Rocks Volcanic Rocks o Active Volcanoes present.
The actual vents which were the sites of the small volcanoes still remain distinct, and the erupted lavas form high ground in the middle of Ayrshire.
The northern chain is of volcanic formation, and contains the peak of Lombok (ii,81o ft.), one of the highest volcanoes in the Malay Archipelago.
Nowhere in the world can there be found another such assemblage of snow-clad peaks, several of which are active volcanoes.
At the same time Cotopaxi and Sangay, the two active volcanoes, have actually increased in elevation since the measurement of La Condamine in 1742.
It has been sometimes classed among the extinct volcanoes, but smoke has been seen issuing from it at different dates, and a violent eruption occurred on January 12, 1886.
Sangay, or Sangai, the next and last large volcano to the south, is in a state of frequent eruption, however, and is known as one of the most restless volcanoes of the world.
Its fame rests on Humboldt's publication of the tradition that great numbers of this tiny fish had been thrown out during the eruptions of Imbabura and other volcanoes.
Among the volcanoes in the province are Tutupacu, the last eruption of which occurred in 1802, Huaynaputina and Hachalayhua, which were in violent eruption in 1606, Coropuna, Ornate, Ubinas and Candarave - the last three still showing signs of activity.
The islands are mainly of volcanic origin, and their surface is much broken by hills, isolated volcanoes and mountain ranges, trending north and south, north-west and southeast, or north-east and south-west.
The greater part of southern Luzon is occupied by isolated volcanoes and irregular masses of hills and mountains.
A line of volcanoes crosses it from north to south, and extensive lava beds cover a considerable part of its surface.
The whole system is volcanic, and a considerable number of volcanoes are still intermittently active, noticeably in central and southern Chile.
Many of the mountains are extinct volcanoes.
In some cases these sedimentary rocks lie deeply buried under lavas poured out by volcanoes long extinct.
It's impossible to discuss volcanoes and not discuss the properties of volcanic ash -- rock that has literally been pulverized into dust or sand by volcanic activity.
The absence of active volcanoes in Australia is a state of things, in a geological sense, quite new to the continent.
In the southern region of unfolded beds are found the lavas of the " harras " of Arabia, and in India the extensive flows of the Deccan Trap. In the central folded belt lie the great volcanoes, now mostly extinct, of Asia Minor, Armenia, Persia and Baluchistan.
The district abounds in geysers, springs, mud volcanoes and other phenomena; some of the waters have petrifying powers, and some of the springs are vividly coloured.
Numerous extinct volcanoes rise near Neuwied.
Among still active volcanoes the following are the best known Name of Volcano Height in feet.
North and east of the Fossa Magna the structure is concealed, to a very large extent, by the outpourings of the volcanoes which form so marked a feature in the northern part of Hondo.
The rift-valley faults continue down the depression, marked by numerous volcanoes, in the region of the Natron Lake and Lake Manyara; while the steep walls of the deep depression of Tanganyika and Nyasa represent the western rift system at its maximum development..
The geography of the Western province includes many interesting features, the in many ways peculiar Albert Nyanza (q.v.), the great snowy range of Ruwenzori (q.v.), the dense Semliki, Budonga, Mpanga and Bunyaraguru forests, the salt lakes and salt springs of Unyoro and western Toro, the innumerable and singularly beautiful crater lakes of Toro and Ankole, the volcanic region of Mfumbiro (where active and extinct volcanoes rise in great cones to altitudes of from 11,000 to nearly 15,000 ft.), and the healthy plateaus of Ankole, which are in a lesser degree analogous in climate and position, and the Nandi plateau on the east of Victoria Nyanza.
While the majority of his researches bear on one or other of the subjects just mentioned, others deal with such widely different topics as the birds of Greenland, ocean temperatures, the Gulf Stream, barometric measurement of heights, arcs of meridian, glacier transport of rocks, the volcanoes of the Hawaiian Islands, and various points of meteorology.
In other areas, however, there is still volcanic activity, and in many cases volcanoes to which only tradition attributes eruptions can hardly be classified as extinct.
Orizaba is sometimes included among the semi-active volcanoes, but this is a mistake.
The principal volcanoes of the Chillan group are the Nevado (9528 ft.) and the Viejo.
It is, however, impossible to subdivide the Sierra Madre into a northern and a volcanic chain; for the volcanoes are isolated by stretches of comparatively low countr y; at least thirteen considerable streams flow down between them, from the main watershed to the sea.
The present volcanoes lie along a line (with offshoots) which runs parallel to the west coast, but some distance to the east of the fissures from which the early Tertiary lavas were poured.
Lava streams are seldom emitted from these volcanoes, the material erupted consisting chiefly of ash and scoriae, which are spread over a very wide extent of country.
There is a railway connecting not only the coalfields of the Ombilin valley with Padang, but also the Ombilin river and the Lake of Singkara with the most productive and densely populated plateaus and valleys, north and south of the line of the volcanoes Singalang, Merapi and Sago.
The group of islands, Cheduba and others, in the north-east, off the Burmese coast, are remarkable for a chain of mud volcanoes, which are occasionally active.
The southern half on the other hand is covered by a mountain range whose chief peaks are situated along the southern border, namely Halimun mountain, the volcanoes Salak, Pangerango and Gede, and the Megamendung.
The precise age of the volcanoes of the Eifel, many of which are in a very perfect state of preservation, is not clear, but they are certainly Tertiary or Post-tertiary.
Kyaukpyu contains numerous "mud volcanoes," from which marsh gas is frequently discharged, with occasional issue of flame.
To the south of Rotoiti is Tikitere, a sombre valley abounding in mud volcanoes, springs and other active volcanic phenomena.
Volcanic in origin - the Jebel ed-Druz is a group of extinct volcanoes - the friable volcanic soil is extraordinarily fertile.
The central part of the Malay Arch;- group is a volcanic region, many of the volcanoes being.
The remarkable line of volcanoes around the whole coast of the Pacific and along the margin of the Caribbean and Mediterranean seas is one of the most conspicuous features of the globe.
On these chains are the volcanoes and many thermal springs.
The depression is marked by a line of volcanoes, including Fuji, and is in part buried beneath the products of their eruptions.
A group of large volcanoes occurs on the limestone platform s6uth of the Grand Canyon, culminating in Mt San Francisco (12,794 ft.), a moderately dissected cone, and associated with many more recent smaller cones and freshlooking lava flows.
During the Tertiary period the great volcanoes of the Andes were formed, and there were smaller eruptions in the Sierras.