COXTIXENTAL CREEP 



357 



friction are of a totally different order, and even in glaciers a consider- 

 able grade is reqiii]*ed to initiate motion. 



The actual argument from example which can be made for the Ter- 

 tiary range's is that of overthrusting. In many places, in Asia, for in- 

 .stance, the thrusting is from the north in accord with Taylor's theory; 

 in other places it is from the south, as in the Alps of Europe, the Atlas 

 Tanges of Africa, and the mountains of northern Venezuela and the West 

 Indies. Thousands of miles of the Tertiary ranges of Xorth and South 

 America are thrust toward the west, while important movements of the 

 same age in the eastern Rocky Mountains were thrusts to the east. Tay- 

 lor states that these are minor matters, and that the theory must be 

 judged by the trend lines. Suess, however, recognizes these northward 

 movements and concludes that they are derived from northward move- 

 ments of one vortex in Africa and another in South America. It would 

 seem that if a certain conclusion is drawn from certain facts in Asia, 

 scientific principles demand a like conclusion from like facts in Europe 

 .and America. 



As evidence of an actual separation of the northern continents from 

 ihe north polar region, Taylor cites the outlines of the west coast of 

 Greenland and adjacent portions of Labrador and the northern islands. 

 According to Taylor, these coasts are linear and the lines of Greenland 

 l&t into those of Labrador, etcetera, to a marked degree, thus indicating, 

 in his opinion, an actual partition of Labrador (and North America) 

 from Greenland. Such a movement is, however, by no means the only 

 •conclusion to be drawn from such a parallelism, even though it be exact. 

 If these straight coastlines are due to Tertiary breaks of one kind, tliey 

 may be due to Tertiary breaks of another kind, and may 1)e ordinary 

 normal faults of Tertiary age. They may not be related to the Tertiary 

 at all but may be Triassic faults. If man had been ^^resent during the 

 closing stages of the glacial epoch he would have seen in the Connecticut 

 Yalley of New England a complete, though small, analogue of Balfin 

 Ba}^ which now separates Greenland from Labrador. He might have 

 concluded, therefore, that the crust of western New England had parted 

 from that of eastern New England. Now that the glacial waters have 

 receded from the Connecticut Valley, we can see, not that the crvstalline 

 rocks east and west of it have been dragged aj)art, but that a block of 

 them capped by the Triassic has been faulted down between them. A 

 similar explanation is perfectly reasonable and perfectly satisfies the 

 known facts of Baffin Bay. 



Furthermore, assuming that Labrador did recede from Greeiihmd, 

 what is the significance of the hole 200 or more miles wide which was 



