AREA B — BOOK CLIFFS. 175 



; marked Ko. 11 are undoubtedly the Green Eiver group of 



■ y, as fossils were obtained from the beds farther east. The 



1 them and the Wahsatch (No. 10 of the section) cannot be 



awn in the western partof the cliffs, as the variegated charac- 



cer c. i. : \fahsatch group noticed farther east is here almost lost. 



A' '-r..fiA.Q 19 the summit is 3,400 feet above the valley. Between 



and 21 , the plateau character is well preserved. The streams 



'- do not canon very rapidly and the angle of dip in the strata 



.t 4P. Grass and sage-brash grow everywhere on the plateau. 



verlooking Grand River Yalley are composed of sandstones 



aiinated greenish sHales with spurs projecting southward 



like faces on the west side, while the eastern slopes are more 



rounue i and grassed over. 



Nf^?. vf riic head of the creek, flowing northwest from Station 21, a num- 

 ber 0-' .sphaltum springs were found. They are really in the district 

 ass^igtsfd to Dr. Endlich's party, but as they were visited by us, I insert 

 the jlestripiion : These springs are found in two canons, marked a and 

 ?> or > ' area B (Plate XI). On the north side of canon a a space 



abi it square is covered with the hardened asphaltum, and a line 



material leads to the crevice above, from which it came, 

 it early on a cool morning and no flow was noticed. Near 

 luij '.. ; V ■;■ :, however, the tar was solt. On the opposite side of the canon 

 'A sinr.lnr sv'ot was noticed, and farther down the caSon four or five more. 

 ;um appeared to come from 'under a steel-gray sandstone, 

 ich is an oolitic limestone. In some places the latter ap- 

 pijcv. '. t.> ii. elude irregular masses of limestone. Canon h was tributary 

 ^o '?. ^r <t ov:. the east side contained an area of about 50 square feet on 

 ardened asphaltum formed the surface. Several points were 

 re it oozed from the side of the canon, but the rocks were 

 Eot 'v;i' exposed. It, however, is at about the same level as those in 

 thi? I's^i^in canon. 



<Two SQlphur springs were noted in connection with the asphaltum. 



Tbey were first detected by their odor. The water flowing over the 



tar has coated it with sulphur. An oily substance was noted on the 



r ...< .- At <,]je water. The temperatures were 45^ F. and 47° F., while 



at 55^ F. The time was 9 a. m. The discovery of these 



due to Mr. J. E. Mushback, of our party. Others of the 



■he same region probably have similar springs, and Dr. 



es the occurrence of asphaltum farther north, which is prob- 



ted in som,e way with this locality. The subject will be dis- 



cu;ic',... '-i~ ais report. 



P., ( .Pen Stations 21 and 23 the divide is narrow, in some places 



ly room enough for the trail. The caiions on both sides are 



is often difficult to find a way of descent. An oolitic lime- 



jd all along the divide, and also fine green shales, that are 



gillaceous. 



ii:r! i-water Fork appears to occupy a slight synclinal depression 



uortlr.v'^iit of Station 23. On the west side of the stream there is a dip 



alrnortt &av north, and on the east side the beds dip a few degrees north 



n lying between Stations 25 and 26 and the edge of Grand 

 Y was not visited, but simply seen from the stations. The 

 r shales continue to form the surface-rocks on the highest 

 the variegated Wahsatch beds showing in the canons, 

 ing Grand River Valley, we find the sandstones of the 



