62 Hershey — Some Western Klamath Stratigraphy . 



lines, probably in part metagabbro, diabase and diorite. In 

 part of the area that properly belongs to the Nordheimer, the 

 shale exists only as large inclusions. Ten miles south of 

 Orleans, the plutonics have so thoroughly usurped the area 

 that 1 gave up tracking the shales. These igneous masses 

 must extend down into the Blue Chert series, but there is also 

 a great amount of igneous material in the latter that has no 

 representative in the Nordheimer. I am compelled to admit 

 that the western portion of the Klamath region has had at 

 least two marked epochs of igneous activity between early 

 Devonian and late Jurassic times. 



No traces of fossils having yet been discovered in the Nord- 

 heimer, its age can only be conjectured. It may be late 

 Devonian, but that would imply a strong nonconformity in the 

 Devonian series. It is more likely Carboniferous. Some of 

 its characters suggest the Baird formation. It might also be a 

 western representative of the Triassic Fit shales, but it is not 

 likely to be any younger. These suggestions show that there 

 is nothing definite upon which to base an argument as to its 

 age. 



On the western side of the fault, a belt from four to seven 

 miles wide is occupied, so far as sediments are concerned, by a 

 series which I have heretofore described as a portion of the 

 Bragdon formation. It is about 5000 feet thick and consists 

 of a rapid alternation of soft black slates (produced by the 

 shearing of thin-bedded shales) and of gray crushed coarse 

 sandstones. The latter occur from top to bottom of the forma- 

 tion and it is difficult to determine that they are more abundant 

 in one quarter than in another. The coarser grains are largely 

 various colored cherts like those common in the Bragdon con- 

 glomerates of the eastern area. In fact, this alleged western 

 Bragdon is identical in essential characters with the eastern 

 Bragdon except that the conglomerates of the latter are here 

 replaced by coarse sandstones, and that it is more highly 

 altered by shearing. I have treated the subject at such length 

 in former papers on this region that it is unnecessary to repeat 

 the comparison any further. Perhaps this western formation 

 is not the Bragdon, but I am as yet so far from convinced of 

 it that I will continue to refer to it under that name ; at any 

 rate, its identity with the original Bragdon is not essential to 

 this paper. It has yielded no fossils except some apparent 

 seaweed impressions several miles north of Orleans. 



The original bedding planes are clearly apparent in the 

 Orleans region so that there is no difficulty in determining the 

 structure. In the central portion of the belt it lies at low 

 angles, inclined to form a slight syncline. Within a quarter 

 of a mile of the fault, near the Klamath River, it dips steeply 



