The Tanana-Kuskokwim Lowland Section in the vicinity of the Tanana 

 River study sites is characterized by extensive g I aciof I uv i a I deposits 

 and large alluvial fans (Figure 9). The area is immediately south of the 



l**!nfi35iJ 



^^^ 



Figure 9. G I ac i of I uv i a I deposits in Dry Creek floodplain, 



Yukon-Tanana Upland section. The Tanana River basin lies in an area of 



discontinuous permafrost. The climate is typified by cold, dry winters and 



warm, relatively moist summers with an annual precipitation of around 32 cm, 

 including about 90 cm as snow. 



The Alaska Range Section is characterzed by glaciated ridges between 

 mountains to 2,900 m (Figure 10). Unmodified moraines and associated drifts 

 dominate the surficial geology. The area is underlain by discontinuous 

 permafrost. Normal temperatures range from 2 to 17 C in the summer and -33 

 to l°C in the winter. An annual precipitation of 43 cm includes 275 cm as 

 snow. 



60 



