TEE KATMAI REGION, ALASKA 



577 



were thaught to imply that its formation was the result of the 

 extrusion of a mass of semi-fluid mud, this deposit was termed " the 

 great hot mud-flow," and has been so described.' 



To the Geophysical Laboratory members of the 1919 expedition 

 the evidence seemed opposed to the idea connoted by the term 



Fig. 6. — -Topographic map of the Valley of Ten Thousand Smokes and adjacent 

 region, from surv^eys made by topographers of National Geographic Society's ex- 

 peditions. 



"mud-flow," and early discussions among us led to the expression 

 of the opinion by Dr. Zies that the evidence was much more in 

 harmony with the idea of the movement of a dry, highly heated 

 mass of sand and pumice than of a water-bearing mud. This 



' Professor Griggs's article in the Ohio Journal of Science (Vol. XIX [December, 191 8] 

 No. 2, p. 117) gives an interesting description of this deposit and its remarkable 

 features. 



