GLACIAL SrC'DlES LV GREENLAND 237 



relatively rigid agency . which did not press the blocks hard 

 upon the lee slope after their removal. 



At the point where the glacier grinds against the projecting 

 side of the East Branch hill, the ice was notably crevassed, the 

 fractures being most open at the side and gradually closing as 

 thev passed away toward the axis of the glacier. They were 

 directed obliquely up stream according to the general law of 

 lateral crevasses. Immediately against the obstructing projec- 

 tion the ice was broken up into numerous blocks and fragments 

 and somewhat piled up against the side of the hill or tumbled 

 back upon the upper surface of the glacier. The same thing 

 occurs on the opposite side where the glacier rubs hard against 

 the Sierra nunatak. 



just north of the point of forceful contact with the East 

 Branch hill, a very interesting instance of contortion and 

 upward thrust was observed. The accompanying figure (67) 

 shows the nature of this better than any verbal description. It 

 may be observed that near the base there are two quite pro- 

 nounced lines which have the appearance of special shear 

 planes. The contortion of the central belt in being forced 

 obli(|uely upward is well displayed in the photograph. While 

 the cause of the phenomena cannot be positively stated, it 

 associated itself in my mind with the obtrusion of the projecting 

 point of East Branch hill immediately below it. Whether this 

 be the cause or not, the phenomena impress me as a clear case 

 of forceful localized thrust with resulting foliation and shear 

 planes. 



At the point where the East Branch glacier joins the Bow- 

 doin glacier, a large amount of debris had accumulated from a 

 medial moraine derived from the Obelisk nunatak lying between 

 the East Branch and the Obelisk glacier. The accumulated 

 rubbish was the terminal dump of the medial moraine. There 

 appeared to be much ice beneath this accumulated debris. It 

 was obvious that both it and the extremity of the East Branch 

 glacier had become essentially stationary. The more active 

 Bowdoin glacier (or the Obelisk glacier, for the two are con- 



