REGION OF THE GULF COAST 183 



the other districts the Pleistocene glaciers were confluent, 

 extended beyond the line of the present coast, and prob- 

 ably reached the sea, although their limit is undetermined. 

 In the high mountain region there has been post-glacial 

 uplift of the mountains, and in connection with that uplift 

 great moraines, which were probably formed at the water's 

 edge, have become part of the land. In the other districts 

 the apparent absence of similar great moraines is pro- 

 visionally explained by the hypothesis that the sea surface 

 then lay lower with reference to the land and that the 

 subsequent submergence of a portion of the land has con- 

 cealed the zone of morainic deposit. 



Assuming that a change has transpired in the relation 

 of land and sea since the epoch of maximum glaciation, it 

 is of interest to inquire whether that change was a sinking 

 of the land or a rising of the sea. The general theory of 

 the subject has not yet reached such a condition as to 

 afford a satisfactory answer, but, on the contrary, is so 

 unsettled as to find advantage in every local determina- 

 tion of the nature of the change which may be made on 

 independent grounds. In the case of the high mountain 

 district, the geologic recency of orogenic movement is 

 indicated in other ways, and the post-Pleistocene emerg- 

 ence of land is therefore referred with confidence to land 

 change rather than water change. In the other districts 

 we have no evidence of recent orogenic change, and the 

 mountains appear to have been produced by the dissec- 

 tion of broad plateaus. The uplands about the Alexander 

 Archipelago and Prince William Sound, and those of 

 Kenai Peninsula and Kadiak Island, all contain traces of 

 uplifted peneplains, the uplift having occurred so long ago 

 that the resulting plateaus were profoundly sculptured 

 before the advent of Pleistocene glaciers. The districts 

 of the Alexander Archipelago and Kadiak Island are also 

 characterized by peneplains near present sea-level; and 



