=) 4002 
of basalt, quartzite, and vein quartz are intermediate between those 
found to be characteristic of the rest of the Sandwich moraine and 
of the Buzzards Bay moraine. The percentage of ‘granite pebbles is 
more like that in the Buzzards Bay moraine, but the proportion of 
volcanic pebbles is more like that of the Sandwich moraine. In other 
words, pebble types of the two moraines are mixed, This may be ex- 
plained adequately as the result of overriding of the northern end 
of the Buzzards Bay moraine by southwestward-moving ice of the Cape 
Cod Bay lobe.. As the ice front fluctuated back and forth ina fair- 
ly narrow. belt, the debris that it was carrying was mixed with the 
debris into which it plowed or over which it advanced. 
Deposits West of the Buzzards Bay Moraine 
Gravels Derived from the Cape Cod Bay Lobe 
_ As the thick, active. .ice of the Buzzards Bay lobe melted back 
‘from the Buzzards Bay moraine, a long, low depression sloping: south- 
westward was uncovered between the western side: of the moraine and 
the ice front (Fig. 7). Sometime. later, while the Cape Cod Bay lobe 
was heaping up the ridges of the Sandwich moraine, its meltwaters 
were unablé to escape through the high western part of the moraine 
onto the high apex of the Mashpee pitted plain and found an outlet 
southward along this ‘trough. Sand and gravel deposits from that 
drainage now. cover most of the surface from the.vicinity of the 
Bourne Bridge southward through Pocasset, Cataumet, and North Fal- 
mouth to West Falmouth, 
The belt of lower ground gine which much of the meltwater es- 
caped was not, however, a smooth, straight:valley. It was littered 
with nee ay of stagnant ice that had been left by the Buzzards Bay 
lobe. Many of them did not melt away to form kettles until after the 
drainage from the north had ceased. Here and there between these 
blocks of ice were hills of debris formed by the glacier that now lay 
west of them. These were kames and bouldery knobs ‘of till, some of 
which still protrude above the later glacio-fluvial deposits. Over 
the lower surfaces between the blocks of. ice and.these depositional 
hills there was probably a veneer of outwash spread from the north- 
west. ~ 
‘The meltwater that issued from the Cape Cod Bay lobe was, of 
course, charged with debris. It must have spread along many shifting 
channels that. formed a .complicated braided pattern as the streams 
found their way around obstructions and moved over the uneven’ land 
surface already floored with loose debris. Water may have been 
ponded for a time against obstructions of stagnant ice or hillocks 
of till. Material washed into such temporary pools would form small 
deltas with steeply-inclined stratification. Gradually the outwash 
materials from the north piled up and-blanketed the earlier deposits 
almost completely; ponds were filled with sediment and disappeared; 
and a smooth plain ‘of sand and gravel, -sloping southwestward, was 
formed in this. trough. This .outwash plain had, however,the shape 
of a very narrow, partly-opened fan. On the north its high apex was 
