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Denver Area
Denver to Pueblo
Colorado Springs Area
Royal Gorge Route
Marshall Pass Area
Gunnison River
Uncompahgre River
Tennessee Pass Area
Eagle River
Colorado River
Grand Jct.- Green Riv.
Green Riv.- Provo
Provo- Salt Lake
USGS History
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Uncompahgre River: Montrose to Grand Junction
(U.S.G.S. Bulletin 707, 1922)
STANDARD-GAGE LINE FROM MONTROSE TO GRAND JUNCTION.
Montrose Area
From Montrose to Delta the
railroad follows the valley of Uncompahgre River in a general course a little west of
north. The country north of Montrose is more broken than that to the south, so that a
general view of the valley can not be obtained from the railroad. Throughout most of the
distance from Montrose to Delta the land near the river is well cultivated, but not far
back from the river there is generally a line of bluffs on both sides of it, which range
in height from 50 to 150 feet. These bluffs are but the fronts of extensive terraces, many
of which are well cultivated, but the traveler can see only the barren shale underlying
them.
For a short distance out of Montrose there is nothing to interfere with the view to the
east, and the great Vernal Mesa, through which Gunnison River has cut its famous canyon,
stands out in bold relief. For some distance the fault noted near Cimarron is still
present, but halfway along the mesa the red sandstone beds of Carboniferous and Triassic
systems may be seen from the train he mesa in gentle curves. The mesa here is an arch - an
anticline, as it is called by geologists - but the middle of the arch has been planed off
by erosion, leaving the granite still at the surface. North of this point there is no
fault on the west side of the mesa.
Along the railroad there is a high-tension electric transmission line, which brings
electric power from Telluride, in the San Juan Mountains, for lighting Montrose, Delta,
and other towns along the road. Olathe (o-lay'the), a place of recent growth, by utilizing
the water supplied by the Gunnison tunnel is becoming a horticultural center. In passing
along the railroad the traveler will note that the farmers of the valley are troubled in
places with strong alkali, which makes the surface as white as if it had been cov
ered by snow. This alkali, which is brought to the surface by flooding, due to
overirrigation, makes farming difficult, but it can largely be removed by subsurface
drainage.
Delta Area
One of the most promising parts of the valley for agriculture is the terrace called
California Mesa, which the traveler may see on the west (left) as he approaches Delta. This mesa is served with water by
canals which divert it from Uncompahgre River at a place far up the valley. Delta is the
county seat of Delta County and was so named because, it stands on the delta formed where
Uncompahgre River enters Gunnison River. The south slope of Grand Mesa, the tableland to
the north, is one of the most noted fruitgrowing regions of western Colorado. The orchards
on this southward f acing slope are protected from frost in much the same manner as those
at Palisade, so that fine crops of apples, peaches, and other fruit are produced here
almost every year. The towns of Hotchkiss, Paonia, Cedaredge, and Austin are particularly
noted for their excellent fruit, which is carried to Delta on a standard-gage branch road
and thence shipped to other markets. Considerable coal is mined at Somerset, the terminu's
of this branch, and finds a ready market in the Uncompahgre Valley.
From Cimarron to Delta the railroad runs entirely on the Mancos shale, to which are due
the breadth of the valley and the smoothness of its sides. At Delta the shale lies in a
great structural trough-a syncline, as it is called by geologists-whose eastern edge rests
on the flank of Vernal Mesa and whose western edge rests on the Uncompahgre Plateau. Below
Delta the railroad changes its course from west of north to almost due west, and it
therefore soon reaches the edge of this shale valley and enters a canyon cut in the
underlying sandstone.
A short distance from the station at Delta the railroad crosses Uncompahgre River and then
runs along the bank of Gunnison River which the traveler has not seen since he left Black
Canyon. Here the Grand Mesa is in full view to the north (right). All the lower slopes of
this mesa are composed of the Mancos shale, which is so soft that it generally forms
valleys wherever it is exposed, but the shale in the mesa is protected by overlying
sandstone that is capped by a thick sheet of solidified lava (basalt). When this lava was
poured out the present lowlands had not been cut, and the whole surface stood at the same
level as that of the top of Grand Mesa. The volcano or volcanic vent from which this great
flow was ejected has not been definitely located, but it may have been at a considerable
distance, for this sheet is probably a part of the great lava flow that covered much of
this general region, a flow whose remnants can still be seen on Grand Mesa and Battlement
Mesa, to the north, on the Flattops, north of Glenwood Springs, and on other high mesas.
If these remnants are not a part of a single flow they are probably parts of independent
flows that occurred at about the same time. As the West Elk Mountains, east of Somerset,
were a center of great volcanic activity at about this time the lava may have originated
there. The striking thing about these lava flows is the enormous amount of erosion that
has taken place since they occurred. The date of the flow can be fixed only as some time
in the Tertiary period, but it was long enough ago to permit the removal from the valleys
of rocks at least a mile in thickness.
The sandstone and interbedded shale, immediately below the lava cap in Grand Mesa contain
beds of coal and were formerly called the Laramie formation, which belongs at the top of
the Upper Cretaceous series, but now they are known
to be older and to correspond with the heavy sandstones that form the, Mesa Verde, in the
southwestern part of the State, and hence they are called the Mesaverde formation. The
same formation carries the coal at Anthracite and Crested Butte, northwest of Gunnison. At
that place the coal beds contain coal of high rank, but in the Grand Mesa, which is
farther from volcanic disturbances, the coal is of much lower rank, most of it being
subbituminous, or what was formerly called " black lignite." A large, mine is
operated at Somerset, but in that part of the mesa which is visible from the river bank
-west of Delta coal is mined only for local use.
On the, left, but not visible in many places, is the broad upward swell (anticline) known
as the Uncompahgre Plateau, which is composed of sandstones that underlie the shale seen
about Montrose and Delta. These sandstones will be seen in the canyon between Delta and
Grand Junction. Around the margin of the plateau the massive red sandstones are deeply cut
by the streams which flow from this upland in rugged canyons that have nearly vertical
walls. These canyons are visible from the trains of the Denver & Rio Grande Western
Railroad from Delta to the Utah State line. The interior of the plateau is unbroken and
consists of a gently undulating upland without marked surface features.
Just after passing Roubideau siding, near milepost 378, the sandstone that underlies the
shale makes its appearance. This sandstone, which contains thin beds of coal, has been
called the Dakota sandstone, but the best authorities now place it in the bottom of the
Mancos shale, and hence the Dakota may not be present. The rocks rise rather steeply in
the direction in which the train is moving, and soon variegated shale and maroon sandstone
may be seen. These rocks are in part the same as those which the traveler may have seen at
many places along the Front Range. A dinosaur skeleton was once found across the river
from Grand Junction in rocks of the same kind.
At milepost 379 the railroad crosses the river, and from this place to Grand Junction
the best views of the canyon may be obtained on the left. In the upper end of the canyon
the walls are composed of variegated shale and sandstone of the Gunnison formation as
shown in Plate
LXXVI, B.
 At first the
only part of the Gunnison formation that is seen is the upper shale, which gives to the
canyon walls bands of rather strong color, but after watching these colors for several
miles one would welcome any change from the everpresent maroon and green. Although the
canyon is fairly narrow and there is not much land in it that can be irrigated, several
at-tempts at irrigation on a small scale have been made. The method used employs no dams
or ditches but only a current wheel, which is placed in the stream in such a position that
the current turns it, and as it is provided with buckets, a small quantity of water is at
each revolution lifted from the river to the top of the wheel, where it is automatically
dumped into a trough that carries it to the land to be irrigated. Although this is a
primitive arrangement it is excellently adapted to the irrigation of small tracts of land.
A number of these wheels may be seen in the canyon.
In general the canyon grows deeper downstream, and at Escalante, siding, milepost 385 (see sheet 7), the second member of the Gunnison
formation-a hard sandstone-appears near the railroad grade. Within a short distance it
rises above the grade, and below it may be seen a dark shale. This shale also rises
downstream, and at milepost 388 the top of a brick-red massive sandstone (Triassic)
appears beneath it on the opposite side of the valley. Wherever it is exposed this
sandstone, on account of its deep and uniform color and its massiveness, is the dominating
feature of the canyon. As the rocks dip toward the northeast and as the general course of
the stream and of the railroad is toward the northwest, the rocks exposed on the two sides
of the canyon are not necessarily the same. Even if the stream followed a straight course
the beds at the same level on its opposite sides in the same stretch would be different,
but the difference is greatly exaggerated because the stream swings from side to side in
great meanders. At many places a point on the outermost part of a bend to the left is more
than a mile from the outermost part of the next bend to the right. The farther the stream
swings to the left the lower or older are the rocks in the canyon walls, and the farther
it swings in the opposite direction the higher or younger are the rocks in the walls.
Wherever the brick-red sandstone rises 100 feet or more above the water there is an inner
box canyon with vertical walls, but where this sandstone is below the water the canyon
walls recede by slopes and terraces. This compound character of the canyoun is shown in Plate LXXVI, A.
At milepost 400, 2 miles beyond Bridgeport siding, the railroad enters a tunnel that is
excavated entirely in the massive brick-red sandstone, which is ideal material in which to
drive a tunnel, for the roof needs no, timber to support it, and the portals are equally
durable. This tunnel is 2,256 feet long-nearly half a mile.
In places the walls of the canyon are about 500 feet high, but they lack both the
ruggedness and the regularity that characterize the other great canyons on this route.
Finally they begin to decrease in height, until, half a mile beyond milepost 410, the
traveler begins to see open country, and soon he finds himself back in the same shale
valley that he left a few miles below Delta. A mile farther along the train reaches the
station in the small village of Whitewater. Here Grand Mesa looms up on the right as the
most conspicuous feature in the landscape. On leaving Whitewater the railroad again enters
the canyon, which, however, is nowhere so deep nor so interesting as it is farther up. Its
walls are composed entirely of rocks of the Gunnison formation, or of rocks lying above
it, and at no place does the brick-red sandstone again make its appearance. The river
meanders broadly, swinging first to one side and then to the other in sharp curves which
make the mileage of the railroad much more than it would be if the course were fairly
straight.
As meanders like those in which the Gunnison flows in this canyon could not have been
begun while the river was cutting the canyon they must have been there before the canyon
was cut, and as geologists are agreed that such meanders can be formed only by a sluggish
stream, the Gunnison of the time when these meanders were young was not so rapid as it is
to-day; it was a lazy river that flowed slowly and wound about in the broad valley in
which it was flowing. The meanders were therefore formed when this part of the country was
essentially a shale plain, above which only here and there mountains lifted their heads.
As already stated, such a plain is supposed to have been in existence when the lava that
now caps Grand Mesa was poured out, so that the meanders which the traveler sees to-day in
the river were probably formed when it was flowing at a level a mile higher than it is
now, before any of the sandstones that now form the walls of its canyons were exposed.
According to this interpretation the meanders are very old and are simply inherited from
the former channel of the river.
Grand Junction Area
Near milepost 420 the Gunnison formation disappears below the river, and from this
point down to the junction of Gunnison River with Colorado River it appears only in
places, and the canyon is cut mainly in the sandstone, shale, and coal beds of the lower
Mancos. The height of the walls also declines, and finally, after skirting the bluff on
the right for a considerable distance, the train passes through a small cut and crosses
the bridge spanning Colorado River and is soon at the station in Grand Junction.
Grand Junction is one of the largest towns of western Colorado. It stands at the junction
of the main line of the Denver & Rio Grande Western Railroad and the line over
Marshall Pass, on the flat plain at the junction of Gunnison and Colorado rivers, and is
therefore on the natural route of railroad travel. Colorado River especially carries a
large volume of water, and as its fall above Grand Junction is considerable it affords an
excellent supply of water for irrigation. Water has been taken from the river for this
purpose by many private companies, but generally it has been taken out only a short
distance above the land to be irrigated, and consequently it has neither sufficient head
nor volume, to irrigate all the land adjacent to the town. Recently the United States
Reclamation Service has dammed Colorado River 20 miles above Grand Junction and is
carrying the water in the, High Line canal to the terrace or bench land back from the
river and near the foot of the Book Cliffs.
Grand Junction is the center of a great fruit-growing country that extends up Colorado
River nearly to De Beque, up the Gunnison a short distance, and down Colorado River to
Fruita and Loma. Apples, pears, and peaches are the principal fruits raised. Views of the
orchards and the method of irrigating them are shown in Plate LXXVII,
A, B. Besides fruits the valley produces vegetables, principally sugar beets and potatoes.
Sugar beets find a ready market at the sugar factory at this place, and many beets are
shipped here from other parts of the two valleys.
The town has broad, well-paved streets, good business houses, and a very attractive
residence section, whose streets are well shaded by trees that afford relief from the rays
of the sun. These trees, together with the orchards, make this part of the valley look
like an oasis in a desert.
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