OILBEBT. 



GREAT SALT LAKE VALLEY. 393 



TheOquirrh range is a mountain ridge rising several thousand feet 



above the plain and composed of Paleozoic rocks. At the northern 

 end Hit's*' are of Carboniferous limestones and quartzites. Therange 



,.iids abruptly at the southern margin of the lake and its strata dip 

 steeply toward the. water. At low stages of Lake Bonneville it pro- 

 jected as a bold promontory, and at, its northern face received the im- 

 pact of waves generated in a broad sheet of water 1 ,000 feet (300 m.) 

 in depth. As a result it is sculptured in the most elaborate and beau 

 tiful manner. Above the Bonneville level tower sea cliffs hundreds of 

 feel in height. At the Provo level terraces hundreds of feet in width 

 are carved from the limestone. At intermediate levels the face presents 

 a succession of minor cliffs and terraces, and at lower levels near the 

 shore of the modern lake are fossil beaches and spits of shingle. A 

 Climb of 600 feet (180 m.) to the Provo terrace will be repaid by a view 

 of the phenomena of fossil shores such as can have few equals. 4i ' 



Tooele rallci/.—T\\vn\y miles west of the Oquirrh range the plain is 

 interrupted by a similar ridge, the Aqui range, and this, too, ends 

 abruptly at the shore of the lake. The lowland between the two moun- 

 tain ridges is called Tooele valley at the north and Rush valley far- 

 ther south. The t wo valleys are separated by a small cross range except 

 at one point where a low pass connects them. Before the formation of 

 Lake Bonneville Push valley was drained northward to Tooele valley 

 and traces of the drainage channel are still to be seen at the pass, but 

 the waves and currents of Lake Bonneville transported an immense 

 quantity of detritus to the pass and built across it a spit so massive 

 that the waters of Push valley have never been able to reopen the way. 

 The Utah Western Railway will carry the party nearly to the northern 

 base of this spit 40 and an Opportunity will be afforded to walk or 

 drive to and along its crest. 



Little Cottonwood canyon.— -The loftiest portion of the Wasatch range 

 is about 1*0 miles (32 km.) south of Salt Lake city, and includes peaks 

 rising 7.000 feet (2,100 m.) above the valley. Little Cottonwood is one 

 of a group of creeks which head in this lofty region, course through deep 

 gorges, and issue upon the plain below, Where they become tributary to 

 the Jordan river. In Pleistocene time the high mountain region gath- 

 ered snows to form a dozen glaciers, and one of these, following Little 

 Cottonwood canyon, protruded a short distance beyond its mouth, 

 depositing lateral and terminal moraines of Alpine type. The ice foot 

 was washed by the water of Pake Bonneville, and the terminal moraines 

 were partly buried by delta deposits. The southern lateral moraine 

 stands as a narrow embankment of typical form; the northern appears 

 to have been afterward overriden by t lie ice. so that its material is spread 

 into a low fiat hill. The walls of the canyon at its mouth are of dark 

 quartzite, but the moraines consist chietly of white granite derived from 



