Geologically Sardinia consists of two hilly regions of Pre-Tertiary rock, separated by a broad depression filled with Tertiary deposits.
Geologically considered, the country may be divided into three regions - a central, and the largest, comprising the whole width of the Aravalli system, formed of very old sub-metamorphic and gneissic rocks; an eastern region, with sharply defined boundary, along which the most ancient formations are abruptly replaced by the great basin of the Vindhyan strata, or are overlaid by the still more extensive spread of the Deccan trap, forming the plateau of Malwa; and a western region, of very ill-defined margin, in which, besides some rocks of undetermined age, it is more or less known or suspected that Tertiary and Secondary strata stretch across from Sind, beneath the sands of the desert, towards the flanks of the Aravallis.
This range separates the Bay of Bengal from the Andaman Sea; and it contains much that is geologically characteristic of the Arakan Yoma, and formations common also to the Nicobars and to Sumatra and the adjacent islands.
Nevertheless, under some of these flows remains of plants and insects of species now living in the islands have been found - a proof that the formation as well as the denudation of the country is, geologically speaking, recent.
Flora.-The pastoral wealth of Uruguay, as of the neighbouring Argentine Republic, is due to the fertilizing constitutents of "pampa mud," geologically associated with gigantic antediluvian animals, whose fossil remains are abundant.
Of all the Asiatic ranges the Himalayan is, geologically, the best known; and the evidence which it affords shows clearly that the folds to which it owes its elevation were produced by an overthrust from the north.
Geologically, spiders date from the Carboniferous Period, Arthrolycosa and others from the coal beds of Europe and North America being closely allied to the existing genus Liphistius.
Geologically, Syria belongs to two distinct regions of the earth's crust, the northern and smaller portion lying within the great belt of folding of southern Europe and central Asia, and the southern and larger portion belonging to the Indo-African area, which, though often faulted, is usually free from crumpling.
The folds are approximately parallel to those of the Taurus, and geologically these mountains may be said to belong to that range.'
Geologically, too, it is individual.
The primary triangulation was completed in 1880, a topographical map coloured geologically (1 :200,000) was published 1889-1897, and in addition to this there are being published an agronomical map on a scale of 1:100,000 (since 1887) and others.
- Geologically Louisiana is a very recent creation, and belongs to the " Coastal Plain Province."
- Geologically, the highlands of Bosnia and Herzegovina are to be regarded, in both their orographic and tectonic character, as a continuation of the South Alpine calcareous belt.
- Geologically Venezuela consists of three distinct regions: (1) South of the Orinoco a great mass of granite, gneiss, pyroxenite and other crystalline rocks, continuous with that of Guiana and probably of Archean age.
The rocks of Falcon are believed by Sievers to belong to the Andean system; while the outlying peninsula of Paraguana probably belongs, geologically, to the same massif as Goajira and the Sierra Nevada de Santa Maria in Colombia.
It seems probable that, in a period geologically not very remote, the " Albertine " system will consist of one great river, extending from the northern slopes of the Kivu range, where the Ruchuru has its rise, to the existing junction of the Victoria Nile with Albert Nyanza.
The Rhine connects the highest Alps with the mud banks of Holland, and touches in its course the most varied geological periods; but the river valley itself is, geologically speaking, of comparatively recent formation.
Geologically, British Burma consists of two divisions, an eastern and a western.
The Isle of Pines, so called from its araucarias (its native name is Kunie), geologically a continuation of New Caledonia, lies 30 m.
There are signs that this coastal strip was until a geologically recent period below sea-level; and that the coast-line is still receding is evidenced by the history of the town of Muza, once a flourishing port, now 20 m.
Geologically they are known to date back to the Oligocene period, and wings believed to be referable to them have been found in Liassic and Jurassic beds.
The Carpathians do not form an uninterrupted chain of mountains, but consist of several orographically and geologically distinctive groups; in fact they present as great a structural variety as the Alps; but as regards magnificence of scenery they cannot compare with the Alps.
There are no glaciers near its sources, although they must have existed there in geologically recent times, but masses of melting snow annually give rise to floods, which rush through the midst of the valley in a turbid red stream, frequently rendering the river impassable and cutting off the crazy brick bridges at Herat and Tirpul.
They owe their origin to depressions of the earth's crust of no very wide extent and not running very far into the continental mass, and geologically they are of recent age and still subject to change.
The latter, to which parallels in geologically similar regions in America are not unknown, is the most probable natural explanation that can be offered.
Wide tracts remain geologically unexplored.
Geologically the region is made up of Carboniferous limestones, clay slates and sandstones, containing anthracite and coal; of Cretaceous marls, chalk, sandstone and greensands - chalk cliffs, in fact, accompany the Don for 200 m.; and of Miocene limestones and clays.
The chief points of correspondence between these two great land masses, besides the southward tapering, are as follows: - (i) The areas of ancient fundamental rocks of the north-east (Laurentian highlands of North America, uplands of Guiana in South America), which have remained without significant deformation, although suffering various oscillations of level, since ancient geological times; (2) the highlands of the southeast (Appalachians and Brazilian highlands) with a north-east south-west crystalline axis near the ocean, followed by a belt of deformed and metamorphosed early Palaeozoic strata, and adjoined farther inland by a dissected plateau of nearly horizontal later Palaeozoic formations - all greatly denuded since the ancient deformation of the mountain axis, and seeming to owe their present altitude to broad uplifts of comparatively modern geological date; (3) the complex of younger mountains along the western side of the continents (Western highlands, or Cordilleras, of North America; Andean Cordilleras of South America) of geologically modern deformation and upheaval, with enclosed basins and abundant volcanic action, but each a system in itself, disconnected and not standing in alignment; (4) confluent lower lands between the highlands, giving river drainage to the north (Mackenzie, Orinoco), east (St Lawrence, Amazon), and south (Mississippi, La Plata).
North America is bathed in frigid waters around its broad northern shores; its mountains bear huge glaciers in the north-west; the outlying area of Greenland in the north-east is shrouded with ice; and in geologically recent times a vast ice-sheet has spread over its north-eastern third; while warm waters bring corals to its southern shores.
The relation of the Americas to each other and to the rest of the world, as the home of plants and animals, is greatly affected by the breadth of the adjacent oceans, and also by the geologically recent changes of altitude whereby the breadth of the narrower parts of the lands and the oceans has been significantly altered.
Geologically the Riouw and Lingga Islands are appendages of the Malay Peninsula, not of Sumatra.
The island consists in the main of limestone, and its elevation above the sea is geologically recent.
Coast of Apulia, Italy, and belonging geologically to the opposite Dalmatian coast; it was indeed separated from the rest of Italy by an arm of the sea as late as the Tertiary period.
The first of these three belongs geographically, and probably geologically, to New Siberia Archipelago, from which it is only 97 m.
Historically and geologically, however, these springs are of considerable interest.
Geologically, they have also been differentiated as the Gneiss Islands and the Trap Islands.
Geologically the anthracite and bituminous coals mainly belong to the same formation, the Carboniferous, and this is especially true of the better qualities; though it is stated by the United States Geological Survey that the geQlogic age of the coal beds ranges from Carboniferous in the Appalachian and Mississippi Valley provinces to Miocene (Tertiary) on the Pacific coast, and that the quality of the coal varies only to a very uncertain degree with the geologic age.
The earliest forms of this class geologically are the Nautiloidea.
Geologically and structurally Cyrenaica is a mass of Miocene limestone tilted up steeply from the Mediterranean and falling inland by a gentle descent to sea-level again at the line of depression, which runs from the gulf of Sidra through Aujila to Siwa.
The prevalence of south-west winds during nine months of the year and of north-west during three (April - June) has a strong influence on the temperature and rainfall, tides, river mouths and outlets, and also, geologically, on dunes and sand drifts, and on fens and the accumulation of clay on the coast.
The southern and larger part of the Rhine province, belonging geologically to the Devonian formations of the lower Rhine, is hilly.
This last, together with some of the Mysidae and the species Glyptonotus entomon, exhibits Arctic characteristics, which has suggested the idea of a geologically recent connexion between the Caspian and the Arctic, an idea of which no real proofs have been as yet discovered.
Fiinen, geologically a part of southern Jutland, has similar characteristics, a smiling landscape of fertile meadows, the typical beech-forests clothing the low hills and the presence of numerous erratic blocks, are the superficial signs of likeness.
Its attendant islands lie mainly to the south and are parts of itself, only separated by geologically recent troughs.
Of the nearest point of the archipelago, and as it belongs geologically to Sweden (from which it is distant only 22 m.) must be considered to be physically an appendage rather than an internal part of the kingdom of Denmark.
Broadly speaking, the Balkan Peninsula may be divided into four areas which geologically are distinct.
But though geologically the one set of mountains must be separated from the other, geographically it is convenient to include within the Southern Uplands the whole area between the Central Plain and the Border.
Geologically, the core of the island consists of crystalline rocks; but in the W.
It is probable that the lakes themselves are evidence of (geologically) a comparatively recent deliverance from the thraldom of the ice covering, which has worn and rounded the lower ridges into the smooth outlines of undulating downs.
Geologically the group is composed mainly of Triassic, Cretaceous and Tertiary strata, penetrated by intrusive rocks.