660 GEOLOGY OF OLD HAMPSHIEE COUNTY, MASS. 



Granby and South Hadley to blend with the extensive delta of the 

 Chicopee River last described.. Starting at the northeast corner of the 

 area, one can trace the coarse gravels of the Belchertown notch (307 feet 

 above sea) southwest continuously to the Granby line, in a band about 50 

 rods wide, resting against sandstone on the north and till on the south, like 

 a river course, the coarse gravels of the notch (6 inches) becoming gradu- 

 ally finer, at the town line consisting of a 1- to 2-inch gravel. Just here 

 the band expands westward and southward in the broad, perfectly hoi-i- 

 zontal Granby plain of fine sand, which extends south with nearly half 

 the full width of the town, and west as a much narrower band, sending off 

 a long lobe south on the east side of Granby Hill, and another broader 

 lobe west of the same hill, which starts south with a bottom of 6 -inch 

 gravel (at 266 feet above sea) but grows finer as it goes south. 



The dejiosits extend still farther west and grow still narrower just south 

 of the notch of the Holyoke range, where the waters seem for a little way to 

 have passed over the bai'e sandstones, and they then expand into the broad 

 sand plain of Moody Corners (in the wood road running north from the 

 Coi'ners fine cross-bedded sands are exposed, above 30 feet thick), which 

 extends west across the north of South Hadley, sending several other lobes 

 southward. We have here two elements, diverse in character and origin, 

 which together form, I believe, the bottom deposits of the lake : to the north 

 are the coarse gravels which have plainly come through the Belchertown 

 notch and been swept southward by a strong current in the many lobes 

 just described, and to the south is the enormous body of the sands of the 

 Chicopee River delta described above. 



Southward the lobes of the northern deposits blend with the sands of 

 the southei-n deposit at a common level without the intervention of any 

 scarp which could indicate difference of age between the two deposits; 

 and this is the basis of the decision indicated above — that they are strictly 

 synclu-onous and together form the flood deposit of the Springfield Lake. 



A further and most interesting conclusion is that the floods of the 

 northern basin continued for a long time to pass across the Belchertown 

 notch into the southern basin after the latter was fully abandoned by the 

 ice, although (1) the level of the sands in the Belchertown notch is about 

 40 feet above the level of the high terrace of the lake to the north, and (2) 

 the abundant kettle-holes show that the water ceased to pass through the 

 notch before the ice had melted out from below the sands spread there. 



