358 



glaciers that swept over the region. The materials of the Seven-Mile Hill 

 deposits and those beneath the lava flows of the Nantan plateau indicate 

 that the glaciers came from the White Mountains to the eastward. This is 

 also indicated by the dip of the clays and sands. But the deposits of the 

 Cibicu divide indicate by their composition that they came from the west 

 and northwest (and possibly from the southwest), as do also the Hinton 

 and Salt river deposits the latter being composed of quartzites, gneiss, vitre- 

 ous Tonto sandstone, Archean and Palaeozoic rocks, and biotite granite, all 

 of which are exposed in the upper Canyon creek region, the Ellison dome 

 and the Tonto basin, and south of Salt river along the western face of 

 the Plateau. It is also quite probable that some of the debris came from 

 the mountains to the northward. 



From the inadequate data at hand it would seem that at least the deixjsits 

 below the partly consolidated conglomerate series are Tertiary, extending 

 to the early Tertiary, as Gilbert. Marvin, and the writer concluded when 

 examining the region, and that the remainder are Quaternary, as was also 

 then concluded. This being the case, as the facts at hand seem to indicate, 

 we would, therefore, have had glaciation here in the early Tertiary, prob- 

 ably in the Eocene period, repeated again in the Quaternary. Laking in 

 consequence of blocking lava flows and faulting probably played their 

 parts as did also the subsequent development of drainage, which is, in 

 part, inverted and, in part, diverted. 



The finding of glacial material forming the opening series of the Eocene 

 in many parts of the world brings again to the fore with emphasis the fact 

 that glacial epochs have occurred at the beginning (or the close) of each 

 great era of geologic time. This raises the question again, Why do geologic 

 eras close? Is there not a cosmic cause? And as the writer has sug- 

 gested in previous publications,* may not these changes both in climate and 

 in the readjusting and rebuilding of the earth's crust be due to results 

 brought about by our solar system having reached one or the other terminus 

 of the great elipse around which it is whirling with its company of planets, 

 meteors, planetoids, secondary planets, and comets, much as our exti'eme 

 yearly seasons are caused by similar positions of the earth with reference 

 to the path it travels around the sun and to the inclination of its axis. 



♦Regan, Albert B., The Glacial Epoch, Trans. Acad. Sci. of Kansas, Vol. XXVI, 

 1913, pp. 70-83 ; Sunspot, Vol. 1, No. 11, January, 1916. pp. 13-30. 



