288 B. L. CLAKK THE MEGAXOS GROUP 



thickness as exposed in the mine at N'ortonvillej is found intercalated 

 ])etween the coarse, white, qiiartzitic sands without a trace of shale. 



Evidence for unconformity betiueen Meganos and Tejon. — The most 

 important evidence for unconformity between the Meganos and the Tejon 

 is the great difference in strike between the beds of the two horizons, 

 seen at numerous localities; this is ver}^ noticeable at the coal mine at 

 StewartYille, where the difference approximates 50 degrees. The basal 

 sandstone of division D is here in contact with the Tejon. the thickness 

 of the standstone being approximately only 150 feet, ^lien followed to 

 the west of Stewartvllle, the sandstone soon disappears and the basal 

 beds of the Tejon rest directly on the upper dark-colored shale (division 

 ("), and a little to the west and south of Xortonville the Tejon rests on 

 the first sandstone member from the top of division C. To the south- 

 east of Stewartville the sandstone of division D emerges from under the 

 Tejon very rapidly, forming the ridge north of Deer Yalley; the shaly 

 sandstones and shales of division E also appear, and within 3 or 4 miles 

 of Stewartville they show their maximum thickness of 1,500 feet. In 

 the canyon to the south of the Star mine, a distance of not much more 

 than a mile from Stewartville, these upper shales of division E are well 

 developed. 



In going to the southeast, besides this difference in strike and the rapid 

 emergence of the upper Meganos beds from beneath the Tejon, a marked 

 difference in dip was obtained at a number of localities. In general it 

 appears that there is a difference in dip between the two horizons through- 

 out the entire length of the area. At the west end of the area southwest 

 of Nortonville there is a maximum difference in dip of 18 degrees between 

 the Upper Meganos beds and those of the Lower Tejon. In the vicinity 

 of Stewartville the difference approximates only about 5 degrees, while in 

 the vicinity of West Hartley the difference is between 15 and 20 degrees. 



In the western part of the area under discussion, heavy conglomerates 

 are found at the base of the Tejon. In some places the conglomerate has 

 a thickness approximating 20 feet. To the east, in the vicinity of Stew- 

 art^■ille and West Hartley, the conglomerate disappears and the chocolate 

 shales at the base of the Tejon rest on the shales and shaly sandstones of 

 division E of the Stewartville. making it impossible to find a sharp con- 

 tact anywhere. As has been already stated, in the western part of the 

 area the l)asal Tejon conglomerate rests on the dark shale of division C, 

 and at a number of localities a sharp contact was located. This contact 

 is decidedly irregular, and the bedding planes of the shale are cut off and 

 butt into the conglomerate. It is a noticeable fact, also, that there is con- 

 siderable carbonaceous material at the contact. 



