242 O. H. Hershey — River Terraces of California. 



The tiny caiion is no wider than the stream and is cut into the 

 rock below the graveL The valley also preserves splendid 

 remnants of the higher terraces np to several hundred feet, 

 especially at the upper end where there is a beautiful display 

 of three sharp terraces, each a rock bench capped with graveL 

 Opposite the village of Hoopa, each side of the valley has a 

 w^ell marked remnant of the principal upper terrace, several 

 hundred feet above the stream and other remnants indicate 

 strongly that at that level the valley once had a flat floor of 

 similar shape and size as the present. 



At the lower end of Hoopa valley, the river leaves the 

 Bragdon slate belt and to its mouth traverses a gorge in Paleo- 

 zoic schists. In ascending the Klamath River from Weitchpec, 

 traces of the terrace system are observed in the canon at 

 various places, particularly at the mouths of Blufl and Red 

 Cap Creeks, but there is no prominent development of them 

 until Orleans is reached. Here for several miles the river is 

 traversing a comparatively soft belt of schist and has eroded a 

 basin over one-fourth mile in average w^idth, the slopes of 

 which are finely terraced. The broad lower -terrace, on which 

 is built the village of Orleans, is the valley floor proper and 

 has a level about 30 feet above the ordinary stage of the river. 

 The stream flows through the basin in a rock canon no wider 

 than the river. Gravel-capped rock benches rise behind each 

 other to a level of 400 or 500 feet above the river and are 

 extensively mined. The main one at several hundred feet 

 seems to correspond in degree of preservation with the main 

 upper terrace on the Trinity River. The altitude of Orleans 

 is nearly 800 feet. 



Continuing up the Klamath River and then up the Salmon 

 River traces of the terrace system are encountered at many 

 places in the canon, particularly at the mouths of tributary 

 streams, but there is no pronounced development of them 

 until ]^ordheimer is reached. From here to the Forks of 

 Salmon, the valley is wide enough to have a well-marked flat 

 bottom, which is traversed by the river in a narrow rock canon 

 cut down from 30 to 60 feet. Discontinuous remnants of the 

 higher terraces up to several hundred feet are present all along 

 the river for many miles. The altitude of the river at the 

 Forks of Salmon is about 1700 feet. 



Up the South Fork of Salmon River, traces of the lower 

 terrace are hardly anywhere absent, except in a few of the 

 narrowest gorges. Wherever the rocks are soft this lower 

 terrace spreads out to a broad, flat gravel bar, always elevated 

 above the present river level. It is well developed at Cecil- 

 ville, altitude about 2650 feet, where the village is built on it. 

 The present canon has a depth of about 25 feet and its usual 



