1S97.] DRAKE — THE GEOLOGY OF INDIA X TEERITORY. 345 



nearly east and west apparently. The uplift of the monoclinal 

 fold being on the riorth side, outcrops of the Silurian strata extend 

 farther east on that side of the fold. Another east and west anti- 

 clinal fold appears to lie about one mile north of Bunch. Silurian 

 rocks are exposed along this uplift one and a half miles northwest 

 of Bunch, and on Elk creek about six miles W. N. W. from Bunch. 

 Lithology of the Salisaw Creek Area. — Marble and saccharoidal 

 sandstone are practically the only kinds of rocks exposed in these 

 outcrops. There is, however, a bed of chert some twenty-five feet 

 thick one-half mile west of Marble, which is most likely Silurian. 

 This chert consists of angular pieces, from an eighth to a fourth inch 

 in diameter, of pink and also white chert scattered through a ground 

 mass of gray chert. At the base of the chert bed, there is some 

 saccharoidal sandstone containing chert nodules. The saccharoidal 

 sandstone usually lies at the top of the Silurian beds in this area, 

 and is from one inch to twenty-five or thirty feet thick. The grains 

 composing the sandstone vary considerably in size : the largest are 

 about two millimeters in diameter. These sandstones may be 

 seen along Walkingstick creek above the Marble bed, at almost 

 every place where the top of the marble is exposed. They also out- 

 crop one-half mile east of Marble on Salisaw creek, and northwest 

 of Marble along Dry creek. The marbles are generally of a pink 

 color, rather coarsely crystalline, seamed, and lie in massive beds ; 

 twenty-five to thirty feet of massive marble is exposed at all the 

 larger Silurian areas marked on PL IV, and the base of the marble 

 was not seen at any place. Mr. J. D. Rice, who quarries marble at 

 Marble P. O., gave me the following section from a drill hole on 

 Dry creek, northwest of Marble P. O. 



FEET. 



Pink marble 25 



Light gray marble 100 



Deep pink marble 2 i 



Dark gray marble 2\ 



Deep pink marble 5 



Dark gray marble • i 



Relation to the Silurian of A?'kansas. — K section^ of the Silurian 

 deposits in Arkansas gives something over one hundred and fifty 

 feet of pink, chocolate and gray-colored marbles on top, which beds 



^ Ann. Kept. Geol. Sur. Ark., 1890, Vol. iv, pp. 10, 11, 214. 



