When the attempt was made to mark this boundary the commissioners were unable to agree on a line across the Puna de Atacama in the north, where parallel ranges enclosing a high arid plateau without any clearly defined drainage to the Atlantic or Pacific, gave an opportunity for conflicting claims. In the south the broken character of the Cordillera, pierced in places by large rivers flowing into the Pacific and having their upper drainage basins on the eastern side of the line of highest crests, gave rise to unforeseen and very difficult questions.
The Cordillera, which bounds them on the west, is formed of folded beds, while the Sierras which rise in their midst, consist mainly of gneiss, granite and schist.
Elsewhere the plants generally indicate a higher horizon and are considered to correspond with the Rhaetic of Europe_ Jurassic beds are known only in the Cordillera itself, and the Cretaceous beds, which occur in the west of the country, are of freshwater origin.
As far west, therefore, as the Cordillera, there is no evidence that any part of the region was ever beneath the sea in Mesozoic times, and the plant-remains indicate a land connexion with Africa.
The Lower Tertiary consists largely of reddish sandstones resting upon the old rocks of the Cordillera and of the Sierras.
Previous to the existence of the strait, and across its site, there poured into Australia a wealth of Papuan forms. Along the Pacific slope of the Queensland Cordillera these found in soil and climate a congenial home.
Lofty lines of fold mountains form the " backbones " of North America in the Rocky of Mountains and the west coast systems, of South America in the Cordillera of the Andes, of Europe in the Pyrenees, Alps, Carpathians and Caucasus, and of Asia in the mountains of Asia Minor, converging on the Pamirs and diverging thence in the Himalaya and the vast mountain systems of central and eastern Asia.
These ranges appear to belong to two systems. The Cordillera of Merida is one of the branches of the Andes, and the strike of the folds which compose it is usually from south-west to north-east.
The oldest rocks in the country are the granites, gneisses, &c., of the southern massif and the crystalline schists which form the axis of the Cordillera and the Caribbean chain.
The Cretaceous beds form a band along each side of the Cordillera and along the southern flank of the Caribbean chain, and they spread over the greater part of the provinces of Falcon and Lara.
Its situation near the high cordillera gives it a cold, changeable climate.
The line adopted starts from Lake Suches, the source of a small river of that name flowing into the north of Lake Titicaca, crosses the Cordillera by the Palomani to the Tambopata river, follows that stream to the mouth of the Lanza, thence crosses to the source of the Heath river, which forms the dividing line down to its junction with the Madre de Dios, descends that river to the mouth of the Torosmonas, thence in a straight line north-westerly to the intersection of the Tahu.amanu river by the 69th meridian, and thence north on that meridian to the Brazilian frontier.
The coast, extending from the base of the Western or Maritime Cordillera to the Pacific Ocean, consists of a sandy desert crossed at intervals by rivers flowing through narrow, fertile valleys.
The Western Cordillera, overhanging the Peruvian coast, contains a long line of volcanic mountains, most of them inactive, but their presence is probably connected with the frequent and severe earthquakes, especially in the southern section of the coast.
Near the Cordillera and on its lower slopes a tall branched cactus is met with, and there are Salicornias and Salsolas near the coast.
From the Gulf of Guayaquil to the borders of the Morrope Valley, and is traversed by three rivers - the Tumbes, Chira and Piura, the two former receiving their waters from the inner Cordillera and breaking through the outer range.
The Nepena, Casma, Huarmey, Fortaleza and Supe rivers rise on the slope of an outer range called the Cordillera Negra, and are consequently dry during the great part of the year.
9 a through the outer range from their distant sources in the snowy Cordillera, and have a perennial supply of water.
Here the Western Cordillera recedes, and the important valley of Arequipa, though on its western slope, is 7000 ft.
The Maritime Cordillera of Peru has no connexion with the coast ranges of Chile, but is a continuation of the Cordillera Occidental of Chile, which under various local names forms the eastern margin of the coastal desert belt from Atacama northward into Peru.
The maritime chain separates into two branches, which run parallel to each other for 100 m., enclosing the remarkable ravine of Callejon de Huaylas - the eastern or main branch being known as the Cordillera Nevada and the western as the Cordillera Negra.
In most parts ofithe Peruvian Andes the line of perpetual snow is at 16,400 ft.; but on the Cordillera Nevada, above the Callejon de Huaylas, it sinks to 15,400 ft.
At the point where the river Santa breaks through the Cordillera Negra that range begins to subside, while the Maritime Cordillera continues as one chain to and beyond the frontier of Ecuador.
The Central Cordillera consists mainly of crystalline and volcanic rocks, on each side of which are aqueous, in great part Jurassic, strata thrown up almost vertically.
The central chain continues to run parallel with the Maritime Cordillera until, at Cerro Pasco, another transverse knot connects it with the Andes in to° 30' S.
The Huallaga rises north of Cerro Pasco, and, passing Huanuco, flows northwards on the other side of the Central Cordillera for 300 m.
The country between the Huallaga and the Ucayali, traversed by the Eastern Cordillera, is called the Pampa del Sacramento, and is characterized by extensive grassy plains.
Geology.'--The Eastern Cordillera., which, however, is but little known, appears to consist, as in Bolivia, chiefly of Palaeozoic rocks; the western ranges of the Andes are formed of Mesozoic beds, together with recent volcanic lavas and ashes; and the lower hills near the coast are composed of granite, syenite and other crystalline rocks, sometimes accompanied by limestones and sandstones, which are probably of Lower Cretaceous age, and often covered by marine Tertiary deposits.
The Cordillera Negra in this region is in many places cut by numerous dikes of diorite, and it is near these dikes that silver ores are chiefly 1 See L.
In the Cordillera Nevada the Mesozoic rocks which form the chain are often covered by masses of modern volcanic rock.
1809), a native of Huamantanga in the Maritime Cordillera, studied under Dr Jussieu, and became an eminent botanist.
Of private lines, the estimated cost to be about £37,500,000-a sum far beyond the resources of the republic. The two transandean lines were the famous Oroya railway, running from Callao to Oroya (1893), which crosses the Western Cordillera at an elevation of 15,645 ft., and later on to Cerro de Pasco (1904), the Goillarisquisga coal mines (1904) and Hauri (1906); and the southern line from Mollendo to Lake Titicaca, which reached Arequipa in 1869, Puno in 1871 and Checcacupe (Cuzco branch) in 1906.
The department includes an arid, sand-covered region on the coast traversed by deep gorges formed by river courses, and a partly barren, mountainous region inland composed of the high Cordillera and its spurs toward the coast, between which are numerous highly fertile valleys watered by streams from the snow-clad peaks.
The department is traversed by the Cordillera Occidental, and is bounded N., E.
Long, which cuts a way through the Cordillera, and enters the Pacific at Istapa, after forming at San Pedro a fine waterfall more than 200 ft.
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.).
The rim of the Valley is formed by spurs of the transverse cordillera on the north and south sides - the Sierra de Guadalupe (650 to 750 ft.
ARAGUA, one of the smaller states of Venezuela under the redivision of 1904, lying principally within the parallel ranges of the Venezuelan Cordillera, and comprising some of the most fertile and healthful valleys of the republic. It is bounded E.
The more southerly of the two Costa Rican ranges, known as the Cordillera de Talamanca, rises south of the Gulf of Nicoya, and extends midway between the two oceans towards the south-east.
It follows exactly the curve of the mainland, and is continued into Panama, under the name of the Cordillera de Chiriqui.
The mountain ranges which form part of the great Mexican Plateau consist of two marginal chains known as the Sierra Madre Occidental, on the west, the Sierra Madre Oriental, on the east, and a broken, weakly-defined chain of transverse ranges and ridges between the 18th and 10th parallels known as the Cordillera de Anahuac. All these chains are known locally under diverse names.
To a part of these ranges has been given the name of Cordillera de Anahuac, but there is no true cordillera across this part of Mexico.
In the main it is a broad trough, wider towards the north than towards the south, and unsymmetrical, Hudson Bay occupying much of its north-eastern part, while to the west broad plains rise gradually to the foot-hills of the Rocky Mountains, the eastern member of the Cordillera which follows the Pacific coast of America.
The Mesozoic sediments were almost entirely laid down to the west and south-west of the protaxis, upon the fiat-lying Palaeozoic rocks, and in the prairie region they are still almost horizontal; but in the Cordillera they have been thrust up into the series of mountain chains characterizing the Pacific coast region.
The Rocky Mountain region as a whole, best named the Cordillera or Cordilleran belt, includes several parallel ranges of mountains of different structures and ages, the eastern one constituting the Rocky Mountains proper.
The highest mountains of the Cordillera in Canada are near the southern end of the boundary separating Alaska from the Yukon Territory, the meridian of 141°, and they include Mount Logan (1 9,54 o ft.) and Mount St Elias (18,000 ft.), while the highest peak in North America, Mount McKinley (20,000 ft.), is not far to the north-west in Alaska.
When its vast area stretching from the international boundary to beyond the Arctic circle is opened up, it may be expected to prove the counterpart of the great mining region of the Cordillera in the United States to the south.
Paraguay proper, or the country between the Paraguay and the Parana, is traversed from north to south by a broad irregular belt of highlands, which are known as the Cordillera Ambaya, Cordillera Urucury, &c., but partake rather of the character of plateaus, and form a continuation and outwork of the great interior plateau of Brazil.
The eastern chain is known as the Andes of Ecuador, or the Cordillera Oriental, and the western as the Cordillera Occidental (Western Cordillera).
This, however, is erroneous, for Whymper located a detached range running parallel with the Cordillera on the west, for a distance of 65 m.