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Earliest Drainage of the Province. 10] 
present ; while farther southward some axial drainage may have 
been developed before the beginning of cycle 1, as defined above. 
This axial drainage was at first consequent upon the folded sur- 
face and afterward became subsequent by the process of stream 
adjustment, but how far the process had gone previous to the 
beginning of cycle 1 is not known. 
1.—CRETACEOUS CYCLE. 
In the post-Paleozoic history of stream development the first 
cycle was long and complex—probably very much longer than 
all the time which has elapsed since its conclusion. It began 
with the final emergence of the western part of the Appalachian 
region above sealevel, near the close of the Carboniferous, and 
ended with the production of the Cretaceous baselevel peneplain 
which has already been described in Part I. It covered a period 
of elevation, deformation and erosion, but the products of this 
erosion were carried far beyond the margin of the sea as located 
in succeeding epochs and deeply buried beneath the later sedi- 
ments; hence we are deprived of the evidence which might be 
afforded by the character of the material, as to the relative eleva- 
tion and slope of the land. It is not known how many partial 
peneplains may have been formed during this time, but it is in- 
ferred that it was in general a period of rapid degradation and 
correspondingly rapid sedimentation. 
As stated above, little is known of the process by which the 
Appalachian valley and the western portion of the province 
was added to the Paleozoic continent—whether the folding and 
emergence took place at the same or at different periods. If the 
corrugation was extremely slow the larger streams may have 
been and probably were able to cut their channels through the 
rising folds and for a long time hold their original or antecedent 
courses toward the northwest. On the other hand, if the folds 
rose rapidly the streams must have been ponded and most of 
them diverted to entirely new courses in the synclines; but by 
the process of river adjustment the final result would be the same 
in either case. The difference would be that if the folding were 
very slow the drainage would be first antecedent and then subse- 
quent, while if it were rapid it would be first consequent and then 
subsequent. Since there is no evidence in this region, so far as 
known, that lakes formed by corrugation ever existed, only the 
first hypothesis—that of slow and long-continued folding—need 
