FEALE.] GEOLOGY EAGLE EIVER. 83 



the creeks g and 7^ flow towards the Eagle they cut deeper and deeper, 

 until tbe gypsiferous beds are exposed. The course of the streams is, 

 in general, north 32^' west, being entirely different from that of Eoche- 

 Moutonuee Creek and its parallel streams. The latter flow north 40° east. 

 The branches between the mouth of the Piuey and the head of the canon 

 above creek / have a direction almost due north. What the exact rela- 

 tion is between the beds on both sides of the Eagle I cannot say. 

 In the shales forming the central masses there is a great variety in the 

 dips, owing probably to a number of minor folds, to elucidate which 

 would have required more time than I had at my disposal. 



On the north side of the river in, Mr. Marvine's district, the red sand- 

 stones overlying the GypvSiferous series dip a little east of north at an 

 angle of from 6° to 8°. On the south side, as we have already seen, the 

 dip is west of north. 



Between the two, therefore, there is either a line of faulting or fold- 

 ing ; I incline to believe the latter. I could find nothing that indicated 

 the existence of a fault. There may have been more than one fold, all, 

 however, very gentle in character. The axis of a synclinal fold, I think, 

 runs along the edge of the hills on the south side, having a direction 

 about north 70° west. The southern half of the fold is all that is left, the 

 other side having been removed by erosion. There was probably 

 another fold between this and the river. Between creek g and the 

 caiion there is a patch of Cretaceous rocks forming a semi-quaquaversal. 

 This was, I think, the head of the synclioal fold referred to abov^e. The 

 cause of the basin may have been the crossing of the first fold by a sec- 

 ond. 



In the hill south of Eagle River, and between it and creek /i, there is a 

 gentle synclinal fold, the axis of whicfi is parallel to the one first de- 

 scribed. In the valley above, with the exception of some irregular dips 

 in the gypsiferous beds, it is obliterated. Just beyond this fold is the 

 anticlinal fold, the axis of which is occupied by the river. This may be 

 a prolongation of the fold between Eagle Eiver and creek </, where we 

 have the volcanic rock capping the hills. The folds seem to radiate 

 from a point near here and to become broader and shallower as we go 

 down stream. I could not determine whether the ends of the strata 

 were broken or not beneath the volcanic material. I will refer to this 

 again in a subsequent portion of the report. 



Below tbe mouth of creek /i, the Eagle is in a canon-like valley 

 which continues to the Grand. As I have already said, this valley 

 is" the axis of an anticlinal fold, the rocks on both sides dipping 

 away from the river, the red sandstones (Triassic) being on top, 

 and pink gypsiferous sandstones below. In the gypsiferous hills 

 or the north side of the river, Mr. Marvine noticed indications of 

 an anticlinal fold that he thinks may be the prolongation of the one 

 in the canon. I am inclined to think, however, that ib was merely a 

 local fold in those beds, and that the river above the canon still keeps 

 in the same axis, although erosion has removed so much material that 

 it is difficult to decide. As I have already mentioned, there is a gentle 

 synclinal fold occupying the hill on south side of the river. It is on the 

 summit, and its axis is parallel to the course of the river. This fold is 

 represented at E in section C, Plate III, which is made on the line G, C, 

 E, F, of map A. Section D is a section across the valley of the Eagle 

 from station Ko. 9, the Eed Beds capping the station resting on the gyp- 

 siferous beds. 



Bordering the river on the north side, a short distance above its mouth, 

 is an irregular layer of eruptive rock, probably basalt, which forms a 



