THE OVERLAND ROUTE— COUNCIL BLUFFS TO OGDEN. 



19 



The to^vii of North Bend (see sheet 2, p. 22) takes its n?_me from 

 the northward hend of Platte River at this point, west of which the 



raihoad foUow^s the river in a southwesterly dhection 

 for a long distance. South of the river, opposite North 

 Bend, the bluffs arc conspicuous, especially west of 

 Morse Bluff, and consist of loess and glacial drift 

 overlying shale of Benton (Cretaceous) age.* 



North Bend. 



Elevation 1,274 feet, 

 ropulation 1,105. 

 Omaha 61 miles. 



This 



time 



the bottom of a sea. It contains many fossil shells of extinct species 

 of marine mollusks, such as oysters (see PL IV, A, Bj ip, 20), clams, 

 and snails, as well as many fossils of types not represented by living 

 forms, such as ammonites and scaphites. It underlies the superficial 

 glacial deposits between Fremont and a point a few miles Avest of 



Schuvler. 



In the vicinity of Schuyler, the seat of Colfax County, little other 



than the cultivated fields on the alluvial plain can be seen from the 



train. The Dakota sandstone, which here lies a little 

 below the surface (sec fig. 3, p. 16), is of economic 

 importance because of the artesian water it contains, 

 and this water is held in confinement by the overlying 



Schuyler. 



Elevatiou 1,348 feet. 

 Popuh\tioTi 2,152. 

 Omalia 73 miles. 



shale. About 6 miles west of the 



wn 



between 



Lambert and Riohland, the traveler passes from the Benton shale to 



ould 



from anything he can see. 



The westbound traveler is here passmg directly toward the center 



dimentarv rocks 



} formed 

 formatic 



m 



Ltions'of the Upper Cretaceous series — the Dakota sandstone 

 and the Benton shale — and now enters upon the third, the Niobrara, 



* The Benton shale lies conformably on 

 the Dakota sandstone, that is, the beds 

 of the Dakota were not affected by erosion 

 before those of the Benton were laid down 

 upon them. In Nebraska and some other 

 areas a thin limestone (Greenhorn) near the 

 middle of the Benton separates a lower 

 Bhale (Graneros) from an upper shale 

 (Carlile). The lowest beds crop out near 

 Fremont, where the Dakota passes under- 

 noath it not to reappear at the surface 

 again toward the west for a distance of 



about 450 miles. It 

 representing the first 



a miirine shale 

 leuosits formed 



after the sea invaded the interior of North 

 America in the Upper Cretaceous epoch. 

 2 The Niobrara limestone, so named be- 1 the Union Pacific Railroad in eastern 



Hiver in northeastern Nebraska, appears 

 to extend across the eastern part of the 

 State in a broad band under Tertiaiy and 

 later deposits. It is exposed for 125 miles 

 along the valley of Kepublican River, but 

 to the north is seen only in Loup Valley 

 near Genoa until Missouri and Niobrara 

 rivers are reached, in Holt, Knox, Cedar, 

 and Dixon counties, where it can be 

 in large exposures. The material is mainly 

 a soft limestone, chalk rock, or limy clay, 

 presenting considerable variation in com- 

 position from place to place. The geologic 

 age of this formation is shown in the table 

 presented on p. 15. It is the youngest 

 Cretaceous formaiiou that is exposed near 



exposures 



Nebraska. 



