Thera is also of special interest to geologists owing to its remarkable volcanic phenomena.
In the African portion Ruwenzori is regarded by some geologists to be a block mountain or horst.
PRE-Roman Britain Geologists are not yet agreed when and by whom Britain was first peopled.
We give below that which seems to us to be the most satisfactory (based very largely on personal acquaintance with most parts of the range), considering, as in the case of the limits of the chain, only its topographical aspect, as it exists at the present day, while leaving it to geologists, botanists and zoologists to elaborate special divisions as required by these various sciences.
A feature of special interest to geologists in the present conditions of the island is the great power of the wind both as a transporting and denuding agent.
Upon them rest the unfossiliferous strata known to Indian geologists as the Transition and Vindhyan series.
This severance, it is true, may be geologically recent, and some geologists see, in the five rapids of the San Juan, remnants of a connecting ridge which the river has swept away.
The Spaniards called them "bolsons " (purses), a term that geologists have retained.
Swedish geologists distinguish between bottengrus (bottom gravel, bottom moraine) and ordinary krossgrus (terminal and side moraine).
A few geologists regard the sedimentary rocks here classed as Keweenawan as Palaeozoic; but they have yielded no fossils, and are unconformable beneath the Upper Cambrian, which is the oldest sedimentary formation of the region which bears fossils.
This older classification, which has little support except that which is traditional, is still adhered to by many geologists; hut the fact seems to be that the system is set off from the Pennsylvanian (Upper Carboniferous) more sharply than the Cambrian is from the Ordoviciao, the Silurian from the Devonian, or the Devonian from the Mississippian.
Naturalists will of course prefer other limits according as they are geologists, botanists or zoologists.
Throughout this vast space of elevated plateau and mountain face geologists now trace a system of main chains, or axes, extending from the Hindu Kush to Assam, arranged in approximately parallel lines, and traversed at intervals by main lines of drainage obliquely.
The hills of the north-western shore afford a variety of granites and crystalline slates of the Laurentian system, whilst Valamo island is made up of a rock which Russian geologists describe as orthoclastic hypersthenite.
Beyond, again, lies a broad furrow, or ` longitudinal fold,' as geologists call it, parallel to the ridges, and then rises the last elevation, a belt of low calcareous hills, on which, here and there among the waves of beech forest, purple or blue with distance, a white cliff retains its local colour and shines like a patch of fresh snow.
140 species,' belonging to the Mollusca, Foraminifera, Echinodermata, Actinozoa and Plantae; but the researches of French geologists made the total number of Madagascar fossils known in 1907 to be not fewer than 280 species.
Dr Hugh Falconer with the assistance of a committee of geologists excavated it.
The place is a centre for artists, geologists and botanists, for the ascent of Snowdon, Moel Siabod, Glydyr Fawr, Glydyr Fach, Tryfan, &c., and for visiting Llyn Ogwen, Llyn Idwal, Twll du (Devil's Kitchen), Nant Ffrancon and the Penrhyn quarries.
This has led certain geologists to classify the Devonian, Carboniferous and Permian into one grand system; E.
The earlier geologists had been in the habit of dividing the Quaternary deposits into an older Diluvium and a younger Alluvium; the latter is still employed in England, but the former has dropped out of use, though it is still retained by some continental writers.
" The occurrence of stones and boulders far removed from their parent source early attracted the attention of geologists, but for a long period the phenomena, now known as of glacial origin, were unexplained, and the drifts were looked upon as little more than ` extraneous rubbish,' the product of geological agents, quite distinct from those which helped to form the more ` solid ' rocks that underlie them."
In the opinion of Russian geologists the separation of the Caspian from the great ocean must have taken place at a comparatively recent geological epoch.
It is probable for this reason that the average conductivity of the earth's crust, as deduced from surface observations, is too large; and that estimates of the age of the earth based on such measurements are too low, and require to be raised; they would thereby be brought into better agreement with the conclusions of geologists derived from other lines of argument.
The north and south direction of the river has been largely determined by faults, though the geologists of the Egyptian Survey are finding that the influence of faulting in determining physical outline has, in some cases, been overestimated.
The upper part certainly belongs to the Cretaceous formation; the lower part has been considered to be of Karroo age by some geologists, while others regard the whole formation to be of Cretaceous age.
Geologists and anthropologists are not yet agreed on the question whether the climate and condition of the country have undergone large changes since these implements were deposited.
The surface in Denmark is almost everywhere formed by the so-called Boulder Clay and what the Danish geologists call the Boulder Sand.
The territory as a whole has been very imperfectly examined by geologists, and no opinion can at present be hazarded as to the mineral wealth or poverty of the company's property.
It is not to be supposed that one of these great geologists was necessarily in the wrong; each had right on his side.
O'Neill, geologists; H.
Zermatt was long known to botanists and geologists only, and has an interesting though very local history.
Some Finnish geologists - Sederholm for one - consider it probable that during the Glacial period an Arctic sea (Yoldia sea) covered all southern Finland and also Scania (Sickle) in Sweden, thus connecting the Atlantic Ocean with the Baltic and the White Sea by a broad channel; but no fossils from that sea have been found anywhere in Finland.
This is due in some degree to the energy of the early British geologists, whose work profoundly influenced all subsequent thought in the science, as may be seen by the general acceptation of so many of the English stratigraphical terms; but the natural conditions were such as to call forth and to stimulate this energy in an unusual way.
This lake lies in a great pit or caldera created by the wrecking in prehistoric times of the volcano Mount Mazama, which according to geologists once had an altitude of about 14,000 ft.
In modern scientific literature the principal Servian names are those of the electrician Nicholas Tesla, the botanist Dr Josif Panchich, and the geologists Dr Yovan Zhuyevich and Dr Yovan Tsviyich (Cynic).
Divergent opinions have been held as to the mode of origin of the East African lakes, especially Tanganyika, which some geologists have considered to represent an old arm of the sea, dating from a time when the whole central Congo basin was under water; others holding that the lake water has accumulated in a depression caused by subsidence.
Its fires are not volcanic, but result from the combustion of coal some distance underground, giving off much smoke and steam; geologists estimate that the burning has been going on for at least 800 years.
Most geologists include the Atlantic with the other oceans in the view they adopt as to its age; but E.
The geographers who have hitherto given most attention to the forms of the land have been trained as geologists, and consequently there is a general tendency to make origin or structure the basis of classification rather than form alone.
Into types has usually had regard rather to geological structure than to external form, so that some geologists would even apply the name of a mountain range to a region not distinguished by relief from the rest of the country if it bear geological evidence of having once been a true range.
Russia, rich in salt-springs, but very poor in fossils, are now held by most Russian geologists to be Triassic. The Permian deposits contain marine shells and also remains of plants similar to those of England and Germany.
Such being the characters of the Quaternary deposits in Russia, the majority of Russian geologists now adopt the opinion that Russia was covered, as far as the above limits, with an immense ice-sheet which crept over central Russia and central Germany from Scandinavia and N.
To judge by the osteological remains which the researches of geologists have brought to light, there was perhaps scarcely a county in England or Wales in which, at one time or another, wolves did not abound, while in Scotland and Ireland they must have been still more numerous.
BONE BED, a term loosely used by geologists when speaking generally of any stratum or deposit which contains bones of whatever kind.
From these structural and palaeontological evidences, geologists suppose that the formation of the cave was carried on simultaneously with the excavation of the valley; that the small streams, flowing down the upper ramifications of the valley, entered the western opening of the cave, and traversing the fissures in the limestone, escaped by the lower openings in the chief valley; and that the rounded pebbles found in the shingle bed were carried in by these streams. It would be only at times of drought that the cave was frequented by animals, a theory which explains the small quantity of animal remains in the shingle.
16) from Marchi's work, when compared with that of the catacomb of Sant' Agnese already given, presents 1 In Rome the three strata are known to geologists as tufa litoide, tufa granolare and pozzolana.
It is possible that some of these rocks are also of Huronian age, but it is doubtful whether the rocks so designated by the geologists of the " Alert " and " Discovery " expedition are really the rocks so known in Canada, or are a continuous portion of the fundamental or oldest gneiss of the north-west of Scotland and the western isles.
They have long been known to geologists and are found at Okhotsk, Siberia, in association with a large mass of perlitic obsidian.
Elie de Beaumont's name is widely known to geologists in connexion with his theory of the origin of mountain ranges, first propounded in a paper read to the Academy of Sciences in 1829, and afterwards elaborated in his Notice sur le systeme des montagnes (3 vols., 1852).
Among other scientists of a later date who have published important works on Brazil are the American geologists O.
His work on palaeontology shows him the predecessor of all the Scandinavian geologists, and his contributions in this field alone would have been sufficient to perpetuate his fame.
A start was made through the efforts of the palaeontologists and geologists, with only indirect or incidental aid from the archaeologists.
Geologists are agreed that littoral and hemipelagic deposits similar to those now forming are to be found in all geological systems, but the existence in the rocks of eupelagic deposits and especially of the abysmal red clay, though viewed by some as probable, is totally denied by others.
Bi ckstr6m after the Norwegian geologists T.
The Bad Lands of the White river are also noted for their wealth of animal fossils, which have been found in such quantities as to cause geologists to believe that the vertebrates perished there in droves during a severe storm or flood.
In1868-1870and1877-1878he was president of the Geologists' Association.
Among the scientific celebrities were de Saussure, the most many-sided of all; de Candolle and Boissier, the botanists; Alphonse Favre and Necker, the geologists; Marignac, the chemist; Deluc, the physicist, and Plantamour, the astronomer.
The term lava is applied by geologists to all matter of volcanic origin, which is, or has been, in a molten state.
The marble and graphite, as well as some other indirect evidence of life less susceptible of brief statement, have been thought by many geologists sufficient to warrant the inference that life existed before the close of the era when the Archean rocks were formed.
These geologists appropriated the term " culm " for the whole of this facies in the west of England, and subsequently traced the same type on the European continent, where it is widely developed in the western centre.
Between 1850 and 1860 French and English geologists were induced to examine into the facts, and found irresistible the evidence that man existed and used rude implements of chipped flint during the Quaternary or Drift period.
The discovery of radio-activity may, by explaining the interior heat of the great bodies of the universe, solve a difficulty which since the middle of the 19th century has been discussed by physicists and geologists - that of reconciling the long duration which geologists claim for the crust of the earth with the period during which physicists have deemed it possible that the sun should have radiated heat.
Until the fourth decade of the 19th century all stratified rocks older than the Carboniferous had been grouped by geologists into a huge and indefinite "Transition Series."
But on the south side the crystalline rocks are succeeded by a broad belt of slates, as to the age of which the evidence is at present conflicting and the opinion of geologists divided.
This and other evidence (which is considered in more detail in the article Archaeology) is now generally accepted by geologists as carrying back the existence of man into the period of the post-glacial drift, in what is now called the Quaternary period, an antiquity at least of tens of thousands of years.
African geologists believe all these remarkable pipes to be connected with volcanic outbursts which occurred over the whole of S.