4S Ailing — Problems of Adirondack Precambrian. 



highly metamorphosed into crystalline limestones, quartz- 

 ites, paraschists and paragneisses. The thickness, the 

 stratigraphy, and the conditions nnder which it was 

 deposited are unknown. From the earliest reconnais- 

 sance the series has been regarded as highly folded into 

 anticlines and synclines, which subsequently have been 

 severely compressed and squeezed. Recently, however, 

 Dr. W. J. Miller has questioned this belief. 2 He says: 

 "That the Adirondack Grenville strata are more or less 

 folded is admitted, . . . but, in the light of recent studies, 

 the writer (Miller) doubts the interpretation of folded, 

 tilted, and foliated structures as due to intense lateral 

 compression." He recognized that steep dips are uni- 

 versal over the area, but that the Grenville was exten- 

 sively folded he denied. In view of the fact that the 

 commercial graphite schists are members of the Grenville 

 series it was an economic necessity to arrive at the truth 

 regarding the structure of the old sediments. The writer 

 went into the field with as unbiased a mind as possible 

 but has been convinced by numerous instances of folded 

 strata that Miller's contention is untenable. 



The graphite schist that outcrops on Bear Pond Moun- 

 tain, in the township of Ticonderoga, Essex Co. (Para- 

 dox Lake quadrangle), was found to have been strongly 

 folded. The summit of the mountain is probably an anti- 

 cline while the south side is a syncline, both of which 

 pitch strongly westward. The present surface so trun- 

 cates the folds that the line of outcrop follows a Z-shaped 

 pattern on the map. On the eastern edge of Hooper 

 Brothers' property, in the township of Dresden, Wash- 

 ington Co. ("Whitehall sheet), the succession of the Gren- 

 ville beds was found to be the reverse of that at the mine. 

 The most plausible explanation is that the rocks have 

 been folded back upon themselves. The rocks all show 

 crinkling and stretching, which is to be expected in such 

 disturbed strata. Another example of anticlinal folding 

 was observed upon the Flake Graphite Company's prop- 

 erty, Greenfield, Saratoga Co. (Saratoga quadrangle). 

 Again one and one quarter miles west of Conklingville 

 (Luzerne sheet) the Grenville rocks are dipping 30 

 degrees north 20 degrees east into a hill. Tracing the 

 beds with care they were found to return sharply on 

 themselves and it was demonstrated that they form a syn- 



- Miller, W. J. : Jour. Geol., 24, pp. 587-619, 1916. 



