Explanation of Plates 



Plate I 



A. — 'McKay lake, showing marl bed underlain by sand and gravel in upper 

 middle of photograph. {Photograph by Canadian Air Board from elevation of 

 1,300 feet.) 



B. — Alternate chocolate brown and grey laminae from McKay lake. Uncom- 

 pressed sediments. Natural size. 



Plate II 



A. — Section of bottom deposit, McKay lake, taken with Albatross sampler, 

 about three-quarters natural size. Sediments compressed; chocolate brown and 

 grey laminated ooze. Pins are separated by 100 double laminae, i.e., one red and 

 one grey laminae. 



B.^ — -Section of bottom deposit, McKay lake, taken with Albatross sampler. 

 Section slightly desiccated. 



(a) I-4- inches, dark grey to black ooze with a little white marl. 



{b) 95 inches, chocolate red ooze. 



(c) 191 inches, greenish olive to deep greyish olive ooze. 



{d) 8 inches, fuscous to fuscous black ooze. 



{e) 2 inches, slate grey clay. 



M. Double laminae of marly material in ooze. 



