156 GEOLOGY OF OLD HAMPSHIKE COUlsTY, MASS. 



THE SAVOY SCIIIST-TIIE UPPER SERICITE-SCHIST. 



DISTKIBUTION. 



A bi-oad band of sericite-schist enters the .State from Vermont across 

 the eastern half of Rowe and the whole of Heath, and as it crosses Charle- 

 mont it extends over into Berkshii-e County. It occupies the western half 

 of Hawley, Plainiield, and Cummington, where, much narrowed, it comes 

 again wholly within the limit of Hampshire County. 



It runs south in a narrow band, 1 to 2 miles wide, of nearly vertical 

 strata or of strata with high easterly dip, across Middlefield, Chester, and 

 Blandford, and in the latter town expands broadly eastward across this town 

 and Russell, attaining a width of above 7 miles. It divides and wraps around 

 the Hoosac schist below, and extends south across Granville in two bands 

 in the east and west parts of this town, on either side of and dipping away 

 from the older formation. The East Granville gneiss thus forms the nucleus 

 of an anticline having its axis inclined to the north, so that the Hoosac and 

 Rowe schists and the Chester amphibolite, and finally the Savoy schist, 

 appear in succession on either flank. On the east the succession can not be 

 followed higher, as the Savoy schist, which forms the long ridge of Sodom 

 Mountain, has at its foot the sandstones of the Trias, covered mostly by the 

 Glacial and post-Glacial beds. On the west the Savoy schist is a closely 

 folded syncline, bounded by the amphibolite band (Chester) on either side, 

 and doublv looped to include Liberty Hill and Sweetman Mountain, and 

 running out to the south before reaching the State line. (See map, 

 PI. XXXIV.) 



On the north, wliere it Iwoadens out so suddenly in folding round the 

 north end of the anticline, it dips under the Goshen spangled mica-schist, 

 and the axis of the anticline is continued northward l^eneath the latter, and 

 by an upward undulation brings up the Savoy schist in an interesting 

 faulted quaquaversal in the middle of Goshen, and again, farther north, 

 brings up once more by a stronger upward curve the underljnng Cambrian 

 gneiss at Shelburne Falls. 



BOUNDARY UPON THE ROCKS BELOW. 



Where the Chester amphibolite band is present in force as a single 

 massive bed, as across Rowe, Chester, and Granville, the transition between 

 the two is very sudden. 



