SIERRAN VALLEYS OF THE KLAMATH REGION 165 



into the mountain valleys, but in the remainder of the Klamath 

 region it is unrecognizable. At many places there are gravel- 

 covered benches which may represent the Red Bluff level, but 

 they are short and do not fall into a definite system. They may 

 just as well represent some subsequent stage in the down-cutting 

 of the valleys. 



Below Lowden's Ranch on the Trinity river the valley con- 

 tains a heavy deposit of gravel, the genesis of which I do not 

 know, but several features of this locality are evident and inter- 

 esting. An inspection of a map of Trinity county will attract 

 attention to an unusual meandering course of Trinity river for 

 about ten miles below Lowden's. Nothing similar occurs any- 

 where else in the Klamath region. The meanders are like those 

 of a sluggish stream on a broad flood-plain. However, this 

 portion of the Trinity valley is quite narrow, and the crooked- 

 ness of the river is due to the crookedness of the valley. It is a 

 meandering valley cut down about 500 feet below the surface of 

 the gravel deposit mentioned above. The gravel ridges on the 

 inside of the curves scarcely anywhere reach the original surface, 

 but we can reconstruct the old flood-plain on which these 

 meanders originated. It was the floor of a valley several miles 

 wide, which was bounded on either hand by steep mountains 

 which rose 500 to 1,000 feet above it. I am not certain that we 

 are not here dealing with another remnant of the Neocene valleys 

 and their alluvial filling,^ but the meanders themselves certainly 

 originated after the uplift and rearrangement of the drainage 

 system. Perhaps the new Trinit}^ river used an old Neocene 

 deposit as a stage on which to perform its evolutions. 



Oscar H. Hershey. 

 Berkeley, Calif., 

 January 28, 1903. 



' Diller has mapped this gravel deposit in the Fourteenth Ann. Rept. U. S. Geol. 

 Surv., Plate XLV, as one of the Neocene areas of Trinity county, but its relation to 

 the other deposits is not clear. 



