Great Basin

“ The most conspicuous topographic features of the better known portion of the Great Basin are long, narrow, and frequently sharp-crested ridges, with a gentle slope on one side and a steep escarpment on the other. The steeper side in a large number of instances is known to be the upraised side of a fault. Each of these basin ranges, as they are termed, may be considered as the upturned edge of a block of the earth's crust, in general from 60 to 100 or more miles long, and 10 to perhaps 20 miles wide. ”

“ But the occasion justified our eagerness. A smooth silicious basin, seventy-two feet in diameter and four feet deep, with a hole at the bottom as in a washing-basin on board a steamer, stood before us brimful of water just upon the simmer; while up into the air above our heads rose a great column of vapour, looking as if it was going to turn into the Fisherman's Genie. The ground about the brim was composed of layers of incrusted silica, like the outside of an oyster, sloping gently down on all sides from the edge of the basin. ”

“ Can you find the man who had any knowledge of the Great Basin, as it is called, that believed there could be an ear of corn ripened in it? There is not that man on the earth, when you have excepted the people called the Latter-day Saints. ”

“ BASIN DEPOSITS DEPOSITS IN DRY BASINS. On desert areas without outlet to the sea, as on the Great Basin of the United States and the deserts of central Asia, stream-swept waste accumulates indefinitely. The rivers of the surrounding mountains, fed by the rains and melting snows of these comparatively moist elevations, dry and soak away as they come down upon the arid plains. They are compelled to lay aside their entire load of waste eroded from the mountain valleys, in fans which grow to enormous size, reaching in some instances thousands of feet in thickness. ”

“ This Great Basin is yet to be adequately explored. And here, on quitting the banks of a sterile river, to enter on arable mountains, the remark may be made, that, on this western slope of our continent, the usual order or distribution of good and bad soil is often reversed; the river and creek bottoms being often sterile, and darkened with the gloomy and barren artemisia; while the mountain is often fertile, and covered with rich grass, pleasant to the eye, and good for flocks and herds. ”

“ When we first approached this valley, there was not a man upon the face of the earth who ever had beheld these valleys of the mountains, or knew anything of the Great Basin, who knew that corn, or any other kind of grain could be raised here. ”

“ In fact, the Great Basin region, as the term has been used on a previous page, there 163 meets the Pacific, and the islands rising from the adjacent portion of the ocean seem to be the summits of mountains of the Basin Range type. Owing to the dryness of the climate in southern California and adjacent portions of Mexico, the deeply alluvial-filled valleys are treeless, and agriculture is only possible with the aid of irrigation. ”

“ FIG. 45.—FREIGHTING BORAX ACROSS THE DESERT The slow crumbling of the rocks, and the setting free of those constituents which are soluble, the work of the streams in gathering the rock waste into the lakes, the dry air and the heat of the long summer days, have all conspired together to give us these valuable deposits in the dried-up lakes of the Great Basin.
No portion of the earth seems to be without value to man. The great bodies of water are convenient highways. The rich valleys and timbered mountains offer useful products. ”

“ The valley, sometimes called the Great Basin, has an elevation of from four to five thousand feet, being surrounded and intersected by mountain ranges, which rise from five to seven thousand feet above the level of the basin. The Wasatch range extends along the east side of the valley; at its western base is a narrow strip of land, the most fruitful in the Territory. In many other parts the soil is alkaline and sterile. In other districts there are fertile basins, with soil of good quality, yielding in places from fifty to ninety bushels of grain to the acre. ”

“ This is an area of interior drainage, made up of many minor basins, of which the chief is that of the Great Salt Lake in Utah. See Great Basin.
The Columbia and Snake River Plateaus. Large areas drained by these streams in Idaho, Oregon, and Washington are of volcanic origin, and along the Snake River in Idaho and Oregon the lavas form plateaus about 4000 feet in altitude. They are a natural desert, since the region is arid, but are capable of great development under the process of irrigation. ”

“ In the case of a large hollow in a very dry climate the rate of evaporation may be sufficient to prevent the water from ever rising to the lip, so that there is no outflow to the sea, and a basin of internal drainage is the result. This is the case, for instance, in the Caspian sea, the Aral and Balkhash lakes, the Tarim basin, the Sahara, inner Australia, the great basin of the United States and the Titicaca basin. These basins of internal drainage are calculated to amount to 22% of the land surface. ”

“ OF the many characteristic features of the arid region of the far West known as the Great Basin, none attract the attention of the traveler more forcibly than the desert mud-plains that have been left by the evaporation of former lakes. ”

“ NOT much more than fifty years ago the Great Basin region, lying between the Rocky Mountains and the Sierra Nevadas, was almost unknown. Previous to 1840, a few daring men had penetrated west of the Rocky Mountains. ”

“ The lower lacustral deposits of the Great Basin, the aqueo-glacial deposits of the Mississippi Valley, and the ancient deltas of the Atlantic slope are correlated, partly because (1) each attests a great and similar climatal episode, because (2) it is evident that each of these episodes was so extreme as to affect the entire breadth of the continent, and because (3) there are no indications among American geologic deposits of other episodes with which these might be confused ”

“ Even the deserts, where living things of every description find the struggle for existence very hard, become indispensable. If the climate in the Great Basin had been moist, the salts would not have been preserved, but would have been carried away to the ocean, from which only common salt could have been recovered in commercial quantities. ”

“ In all the valleys throughout the Great Basin are to be seen traces of water, and on the sides of the hills water-marks have been left that are visible at the distance of a mile, and can be traced for many miles. ”

“ Many of the depressions in the Great Basin, as well as some of the outlying valleys referred to, have rivers and lakes which exhibit certain interesting features that are unfamiliar to people dwelling in humid lands. The streams are fed in part by the small precipitation on the desert valleys, and by springs, frequently of heated water, but mainly by the rain and melting snow on the mountains. ”

“ So, too, the section of the Cordilleras lying to the east of what is commonly called the Great Basin, between the Rocky Mountains and the Sierra Nevada, has also enjoyed a long reign of peace. In glaciated countries the record is naturally less clear than in those parts of the world which have been subjected to long-continued, slow decay of the rocks. Nevertheless, in those fields boulders are often found poised in position which they could not have maintained if subjected to violent shaking. ”

“ In leafy regions, blessed with copious rains, we learn to measure the productive capacity of the soil by its natural vegetation. But this rule is almost wholly inapplicable here, for, notwithstanding its savage nakedness, scarce at all veiled by a sparse growth of sage and linosyris [16] , the desert soil of the Great Basin is as rich in the elements that in rainy regions rise and ripen into food as that of any other State in the Union. ”

“ Greater pressure of some portions of the crust than of others upon the plastic interior would induce each phase of upward energy in mountain-building. Where isolated blocks of the crust yielded slowly to the resulting quasi-hydrostatic pressure of the interior, mountains of the Uinta type were formed; but large areas, as the Great Basin, being swelled upward and anon subsiding, as the interior pressure increased and diminished, have become marked by tilted mountain ranges. ”

“ The rock floor of the coal basin contains a variety of ancient materials. Some rocks were river deposits, some were marine limestones, a few were lava and volcanic ash, and many were granite and gneiss which crystallized at great depths and became exposed only after streams had stripped away the thick overburden. The basin floor thus holds a complex story, in which land and sea, vulcanism and quiet, erosion and deposition, all played their respective roles. Only in the west, along the margin of the Connecticut Valley, is the involved story at all clear. ”

“ There are stony wastes, or alluvial fans, where mountain streams emerge upon the plains, in time of flood, bringing detritus in their torrential courses from the mountain canyons and depositing it along the mountain base. The barrenness extends into the mountains themselves, where there are bare rock cliffs, stony slopes and a general absence of vegetation. With increasing altitude vegetation becomes more varied and abundant, until the tree limit is reached ”

“ Guided by the principle that great oceanic basins are to be considered rather as original marine areas that have been limited by the elevation of their boundaries, than as having been formed by the excavation of terrestrial areas, we have to inquire what evidence there is that the basin of the Atlantic has undergone any considerable change within a compara tively recent period. ”

“ There are several large arid wastes within the basin, such as Great Salt Lake Desert, Carson Desert, and Mohave Desert, and the climate of the whole region is dry. Agriculture is confined to irrigated lands, but the mineral resources are of great importance. ”

“ Contentment and satisfaction are great somnifacients. The Grand Basin was glorious in sunshine, the peaks crystal-clear against a cloudless sky, the huge blocks of ice thrown down by the earthquake and scattered all over the glacier gleamed white in the sunshine, deep-blue in the shadow. We wound our way downward, passing camp site after camp site, until at the first place we camped in the Grand Basin we stopped for lunch. Then we made the traverse under the cliffs to the Parker Pass, which we reached at 1.30 P. M. The sun was hot ”

“ Without these mountains, whose gorges are fed during the spring, and even in the summer, by melted snow, there would be no water. The levels of the valleys are still unknown; it is yet a question how far they are irregular in elevation, whether they have formed detached lakes, or whether they slope uniformly and by steps toward the Great Salt Lake and the other reservoirs scattered at intervals over the country.
The water-shed of the Basin is toward the north, south, east, and west: the affluents of the Columbia and the Colorado rivers carry off the greatest amount of drainage. ”

“ Nothing can be a clearer truth than that this great difference of chemical and mechanical deposits requires the supposition of some great physical revolution in the relations of land and sea. If we suppose that, in consequence of a subterranean movement somewhere, the oceanic basins were filled by sediments from other lands, or other lines of wasting coasts, the change from coloured sandstones to oolitic deposits in the same basin would be intelligible, though we might never know the local position of such tracts of land or lines of coast. ”

“ A description of the descent of flood waters from the highland tributaries into the Central Basin has been given in Water-Supply Paper No. 88. It has been shown that the lands of the Central Basin are covered even in ordinary freshets, and that in the event of a great flood the waters merely rise higher, being, for the greater extent, almost quiescent, and beyond the flooding of houses and barns and the destruction of crops, little damage is done. ”

“ Its form is approximately that of an isosceles triangle, with the sharp angle extending into Lower California, W. of the Colorado river; the northern edge being formed by the divide of the drainage basin of the Columbia river, the eastern by that of the Colorado, the western by the central part of the Sierra Nevada crest, and by other high mountains. The N. boundary and much of the E. is not conspicuously uplifted, being plateau, rather than mountain. ”

“ It is these heavy rains, of brief duration, when great volumes of water rapidly run off from the barren slopes, that cause the deep channels, or arroyas, which cross the desert. Permanent streams are rare. Many mountains are quite without perennial streams, and some lack even springs. Few of the mountain creeks succeed in reaching the arid plains, and those that do quickly disappear by evaporation or by seepage into the gravels. In the N.W. there are many permanent lakes without outlet fed by the mountain streams ”

“ The quantity of mud, sand, and pebbles constituting many a modern delta proves indisputably that no small part of the inequalities now existing on the earth's surface are due to fluviatile action; but the principal valleys in almost every great hydrographical basin in the world, are of a shape and magnitude which imply that they have been due to other causes besides the mere excavating power of rivers. ”