42 GUIDEBOOK OF THE WESTER:?? UNITED STATES. 



of fragments of tlie diabase, were also formed. This tuff contains 

 fossils of the same kinds that are found in the sandstone. As Wilbur 

 is approached some of the sandstone may be seen overlying the 



l1 forming prominent bluffs on the 

 Wilbur the railroad crosses some 



Winchester. H 



North Umpqua River is crossed. To the left is a miU 

 Wilbur. dam, a place of fascinating interest during the 



Elevation 493 feet. salmou seasou^ when the big fish endeavor to jump 

 Population 354.* over the dam instead of going up the fish ladder. 



Between Winchester and Roseburg the railroad 

 crosses two areas of Eocene sandstone^ but these are 

 entirely suiTounded by diabase, which continues to 



Winchester 



Elevation 482 feet. 



seattVsTQ miles. ' be the prevalent rock along the route as far as Green, 



30 miles from Winchester. 



A mile north of Koseburg the railroad reaches South Umpqua Eiver, 

 which unites with the North Umpqua to form the main stream in 

 Garden VaUey, a few miles to the northwest. At the left arc bluffs of 

 lava in which are inclosed some fragments of Eocene shale, as shown 

 in Plate XIII (p. 35). Deer Creek is crossed just north of the town. 



From Roseburg^ wliich is the seat of Douglas County, a stage line 



runs across the Coast Range to Myrtle Point and Coos 

 Roseburg. Bay. This bay is one of the important harbors of the 



Elevation 487 feet. wcst coast and the port of shipment for the Coos Bay 

 SftHpS^mSs" ^^^1 fi^l^7 which produces more coal than any other 



field in Oregon. 



The bold hills about Rosebm-g are all composed of diabase. About 

 15 miles northeast of the town, on Little River, a tributary of the 

 North Umpqua, above GHde, Eocene fossils are abundant. 



A mile south of Roseburg the deeply decomposed diabase affords 

 good examples of spheroidal weathering. Specimens were collected 

 here for the educational series of rocks prepared by tlie United States 

 Geological Survey and distributed in 1898 to aU the higher educa- 

 tional institutions of the country. 



At Green there is a sudden change to the older rocks that compose 

 the Klamath Mountains — conglomerates, sandstones, and shales of 



Cretaceous age, associated with more siliceous rocks. 

 Green. hard sandstones, and cherts of Jurassic age, and slates, 



•Elevation 537 feet. limestoncs, and grecnish lavas of Devonian and Car- 



Seattle 389 miles. ^ -n 



bomferous age. 

 The core of the Klamath Mountains is composed of large masses 

 of granitic rocks and serpentine, which are intruded into the Devon- 

 ian, Carboniferous, and Jurassic rocks Just mentioned. These 

 older sedimentary rocks cross the country traversed by the railroad 

 between Roseburg and Medford, occurring in belts running northeast- 

 ward toward the Blue Mountains. 



