ABSTRACTS OF PAPERS 87 



does nowadays, the sealevel being regarded constant. That the southern Hud- 

 son region at that time was elevated was vindicated by J. B. Woodworth 3 on 

 physiographic evidences already in 1905. 



Thus, when the land-ice receded from New England the southern part was 

 somewhat elevated, whereas the rest of the region was submerged, and the 

 more so the farther one comes northward. As a result, series of lakes were 

 ponded off the ice-edge as it withdrew. In these lakes the varve sediments 

 were deposited. A great number of profiles were measured in clay-pits and 

 natural exposures. One measurement overlaps the other, and the principal 

 result is an almost continuous series of annual layers registering the recession 

 of the ice-edge from Hartford, Connecticut, to Saint Johnsbury, Vermont. 



The material is not yet sufficiently worked up to permit me to give exact 

 figures, and to publish approximate ones does not seem appropriate. However, 

 the retreat of the ice-edge from Hartford to Saint Johnsbury took some thou- 

 sands of years. The recession was interrupted by some halts and readvances, 

 but on the whole it gradually increased from less than 200 feet a year in 

 northern Connecticut to about 1,000 feet south of Wells River, Vermont. 



Presented extemporaneously, with lantern slides. 



Discussed by J. F. Kemp, who gave a brief description of the technique 

 of the De Geer Method of investigating the laminated clays; by J. W. 

 Goldthwait, who spoke of the immense volume of data collected in the 

 last seven or eight months, and by H. F. Eeid and Frank Leverett. 



STRUCTURE OF THE CONNECTICUT BASIN DURING THE NEWARK EPOCH 



BY WILBUR G. FOYE 



(Abstract) 



Among the most important unsolved problems of the Connecticut Triassic 

 basin is the question of the nature of the depression within which the Newark 

 sediments accumulated. Two diagrams of the conditions which initiated the 

 sedimentation are most frequently given in the textbooks. The first, by Davis, 

 shows the depression to be due to the downwarping of a peneplaned surface. 

 The second, by Barrell, indicates that the depression was developed by the 

 tilting of a monoclinal fault-block. In his original paper, Professor Davis 

 recognized that the graben theory for the origin of the valley was possible ; 

 but, in the absence of conclusive ' evidence, the diagram was constructed to 

 show a warped peneplain. The writer believes there are strong reasons why 

 the diagram by Barrell should supersede the more widely recognized diagram 

 by Davis. 



Presented from notes, with lantern slide illustrations. 



Discussion was participated in by W. J. Miller, J. B. Woodworth, 

 W. M. Davis, C. E. Gordon, C. E. Longwell, IT. B. Kiimmel, W. N. Rice, 

 and L. S. Westgate, with reply by the author. 



3 J. B. Woodworth: Ancient water levels of the Champlain and Hudson valleys. New 

 York State Museum, Bull. 84, p. 229. Albany, 1905. 



