58 



NEW YORK STATE MUSEUM 



amphibolitic — cut by several white, fine-grained, aplite dikes and 

 a pegmatite dike. The relations are brought out in figure 4. 



The stock southeast of North pond shows large developments 

 of very gneissoid to amphibolitic facies of gabbro, especially in its 

 eastern portion. A ledge of rather typical, medium-grained gabbro 

 just east of the brook one-fourth of a mile north of its junction 

 with Rogers brook, contains many lenses and strips of nearly 

 Avhite Whiteface anorthosite as inclusions with parallel arrange- 

 ment. A number of small faults intersect the ledge. The rela- 

 tions are brought out in figure 5. On the small hill in the west- 

 ern part of the area, typical nonfoliated gabbro is involved with 



Fig. 5 A sketch o£ part of an outcrop near the brook at the southern 

 margin of the gabbro stock southeast of North pond. The normal gabbro 

 (cross-lines) contains manv r,arallel strips of VVhHeface anorthosite (black), 

 and the whole is intersected by several minor faults. 



Nvell-foliated gabbro, these two facies forming zones or belts not 

 very sharply separated from each other. This foliation is very 

 clearly a flow-structure due to magmatic currents, with the wavy 



