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The Ohio Journal of Science [Vol. XIX, No. 2, 



PROBABLY ERUPTED FROM SEVERAL FISSURES. 



From this fact it becomes at once evident that it could 

 not have come from a single orifice, for there are two distinct 

 summits from each of which it flowed in both directions. One of 

 these is Katmai Pass, the other is in the vicinity of Novarupta 

 Volcano. The altitude of both is in the neighborhood of 3,000 

 feet. From Katmai Pass the mud flow not only reaches into 

 the Valley of Ten Thousand Smokes, but extends down the 



li 



Photograph by D. B. Church 



PART OF THE MUD FLOW ACROSS THE PASS FROM THE VALLEY. 



Looking toward Observation Mountain from the upper flat of Mageik Creek. 



The layers of Katmai ash covered by a secondary flow are plainly 



shown in the bluff, two- thirds of the way up. 



valley of Mageik Creek to the foot of Observation Mountain, 

 against which it accumulated to a thickness of 30 or 40 feet. 

 (See picture above). 



Novarupta, although situated in the floor of the Valley, is 

 located near a col which separates the two arms of the Valley 

 that encircle the Broken Mountains. On the west side of 

 this col the surface of the mud flow descends till it joins the 

 branch coming down from the Pass at an altitude of about 

 2300 feet, then continues its descent across the front of Cerberus 

 and Mageik down the main valley to the terminus of the flow, 



