472 SAMUEL WEIDMAN 



along joints and fissures in the closely folded and faulted pre- 

 Pennsylvanian rocks of the Arbuckle region. Detached from their 

 position along fissures some slickensided specimens might be taken 

 for specimens showing glacial striae, but no one observing such phe- 

 nomena should have any difficulty in distinguishing glaciated sur- 

 faces from purely rock pressure surfaces in field exposures, because 

 they are formed under quite different geological conditions, and are 

 invariably to be observed under entirely different geological environ- 

 ments. 



It should be stated in this connection that the most abundant 

 striations and other evidences of supposed glaciation appear to be 

 associated with one of the latest, if not the latest, conglomerate, 

 deposited in both the Arbuckle and Wichita regions. This is especi- 

 ally true of the striations on the rock floor on which the latest con- 

 glomerate rests. However, some striated boulders and pebbles 

 within the conglomerates have also been discovered in much earher 

 beds. 



STRIATED ROCKS IN THE ARBUCKLE MOUNTAINS 



The striae thus far observed on the rock surfaces beneath the 

 conglomerate in the Arbuckle region range from fine lines to fairly 

 prominent grooves reaching an inch in width and one-fourth inch 

 in depth. They usually run in nearly parallel directions and form 

 distinct markings varying from a few inches to several feet in 

 length. 



The striated rock surface, shown in Figure 2 was found along the 

 Santa Fe Railroad about 2^ miles north of Daugherty, where the 

 underlying floor is exposed beneath a small projecting mass of the 

 conglomerate. After two attempts by the writer to take a satis- 

 factory photograph of this example in the field had failed, a frag- 

 ment of the striated floor, (Fig. 2) was removed and photographed 

 in a studio at Norman. The striae at this place have a trend N. 

 25° E., as indicated by their position combined with the fact that 

 the conglomerate overlying the striated floor contains abundant 

 porphyry boulders and cobbles derived from porphyry outcrops 

 (East Timbered Hill) which occur to the west. One of these por- 

 phyry cobbles which exhibits distinct grooving, and finer striations 



