l)'2S K. M. KINDLE DEb\)KIM ATIOK IN NOVA SCO'JM A AND ONTARIO 



thick. The sand of these delta deposits, where it is in contact witli the 

 side of the tank, shows as a black band above the clay in lignres 4 and 5. 

 The inequality of the load of sediment thus placed on the soft clay bed 

 resulted in the unequally weighted clay breaking through the weakest 

 point in the sand-bed covering it and forming a small clay dome or plug 

 extending through the sand, as seen in the photograph, figure 4, directly 

 under the arrow. This occurred at the completion of the second delta. 

 After this photograph was taken the sand load on the clay was consider- 

 ably increased to a nearly uniform depth over the clay. By means of 



i 



Figure 4. — Stratified Clays (iciwsited from Water in experimental Tanlc 



Showing- "mud lump" and deformation produced by differential weighting of the clay 

 beds with sand. The surfaces of each of the four strata below the sand were perfectly 

 horizontal before the introduction of the sand. Note the great disturbance of the char- 

 coal band in lower half of section and the clay plug pushed through the sand below the 

 arrow. 



current scour the sand was then somewhat reduced in thickness at one 

 point, a small tube being used to introduce a stream of water for this 

 purpose. Additional pressure was then placed on the sand by means of 

 a bag of shot. This resulted in the clay slowly rising at the point where 

 the sand load had been reduced on the side of the tank by scour (figure 

 5). The mass squeezed out through the sand assumed the shape on the 

 upper surface of a steep-sided half dome, the contact with the face of the 

 tank preventing the formation of a complete dome. The plug of clay 

 continued to rise till it was slightly above the surface of the water in the 

 tank. Examination of the photographs shows that marked disturbance 



