24 NEW YORK STATE MUSEUM 



VI 



REPORT ON THE GEOLOGICAL SURVEY 



In the last season the Director was obliged to take a large per- 

 sonal risk in order to continue field operations of an important 

 character, because of the failure of adequate provision for this 

 purpose. Only the well-worn appeal to the loyalty of some of 

 the more patient members of the geological staff and the generous 

 disposition of others in deferring immediate compensation for 

 their work has made this active field service possible. 



AREAL GEOLOGY 



In the work directed toward the completion of the great geologi- 

 cal map of the State on a scale basis of one mile to the inch, con- 

 siderable progress was made in the Adirondack region by Prof. 

 H. P. Gushing, Prof. W. J. Miller and Prof. C. H. Smyth, jr, who 

 was associated in the field operations with Dr A. F. Buddington. 



The geology of the Gouverneur quadrangle was in part reported 

 upon last year. Professor Cushing's report on his later operations 

 follow : 



The Gouverneur quadrangle. With the exception of scattered 

 patches of Potsdam sandstone, most of them very small, the entire- 

 area of the quadrangle is occupied by Precambrian rocks. Early 

 Paleozoic sediments seem to have once covered the entire quad- 

 rangle and to have been entirely removed by erosion except for 

 these Potsdam remnants. This sandstone was deposited on the 

 worn and irregular surface of the crystalline rocks and the patches 

 which remain are those portions of the sand which were deposited 

 in the deeper depressions of the old surface. Stach depressions 

 were substantially in all places where limestone was the surface 

 rock, and all the patches which remain rest upon limestone. In 

 many of them a small thickness of conglomerate is found at the 

 base of the sandstone, the angular pebbles having been derived 

 from the thin bands of quartzite in the limestone. The sandstone 

 is either red or gray in color and for the most part very thoroughly 

 indurated. It was deposited on sloping surfaces, for the most part, 

 and its dips rudely conform to these slopes. Locally the limestone 

 surfaces were intersected by joint cracks which had become 

 widened by solution, these became filled with sand, and such sand- 

 filled cracks still remain in places where the remainder of the 

 sandstone has been entirely worn away, and appear like dikes 



