58 Smithsonian Exploration in Alaska in 1904 



" Now to consider the geological structure of the terrace more 

 closely, (i) Above is to be found an earthy layer, covered with 

 moss, 30-52 centimeters (12-20 inches) thick. (2) Under this a 

 layer from 2-4 meters thick composed of layers of clay with coarse 

 shingle corresponding, petrographically, to the rocks of the nearby 

 mountains. With the shingle in this layer was also found pieces 

 of wood, bones, etc. Through this clayey and loamy deposit be- 

 sides the stones, roots, and pieces of wood, were lamellar layers of 

 ice up to 15-18 centimeters thick, stretching through the mass. 

 (3) Underneath this alluvial layer there is a vertical wall of ice 

 five and even seven meters thick. With this ice wall the section 

 closes, because below it comes the sliding talus to be found every- 

 where along the slope of the terrace. Under the place where the 

 mammoth lay Herz dug to the depth of 2.25 meters. At first the 

 excavation passed through deposits of earth alternating with thin 

 layers of ice, but at a depth of 1.90 meters a compact mass of ice 

 was found, which was not passed through at 2.25 meters depth." 



Tolmatschow reviews the several suppositions that may be drawn 

 about the thickness of the fundamental ice bed, for it appears in 

 the Beresowka section the lower surface of this ice was hidden by 

 talus. He does not think that it extends down to the level of the 

 Beresowka as Herz thought,*'^ and it is not represented that way in 

 the profiles given, because in this case the structure of the bank 



would be quite different Tolmatschow says : " The large 



dimensions of the sliding mass make me suppose that under the 

 ice wall and high above the level of the Beresowka are to be found 

 other deposits of clay and loam. The photographs (pi. viii) and 

 the sketches made by Herz give the sharp contrast between the 

 vertical ice wall and the slope of the bank. If the thickness of the 

 ice was greater there could not be such a contrast." 



The writer can state that in apparently analogous cases observed 

 in Alaska the ice rests on top of considerable thicknesses of homo- 

 geneous Pleistocene clays such as appear to form the body of the 

 terrace on the Beresowka. 



" By the washing away of these deposits the ice sheet above is 

 undermined, the layers become loosened so that they fall and slide 

 little by little with all that is to be found on them. Only in this 

 way it seems to me, can be explained the singular fact that the 

 mammoth, which lay in a sliding place, therefore in a secondary 

 deposit, was found nevertheless in such a way, that there can be 

 no doubt left about the place and position from which it has fallen." 



" See translation, Smithsonian Rep., 1903. pp. 616, 618. 



