PHYSICAL OCEANOGBAPHY OF THE GULF OF MAINE 



617 



described. On the western member of the pair (fig. 58) this appears as a core (10°) 

 over the offshore edge at a depth of 30 to 80 meters, but as a body of cold bottom 

 water (8°) well in on the bank on the eastern profile (fig. 59), with the column of 

 water nearly homogeneous in temperature from surface to bottom (inclosed by 

 isotherms for 10° and 12°, evidence of active tidal mixing) on the northeastern part. 



Stations 



Meter 



Fig. 59.— Temperature profile running from the eastern side of the basin, southeastward across the eastern end of Georges 

 Banli to the continental slope, July 22 to 23, 1914 (stations 10220 to 10225) 



AVith the August profile crossing the shelf off Marthas Vineyard (fig. 60), they 

 also afford an instructive demonstration of the continuity of the zone of warm 

 bottom water (10°) all along the offshore slope of Georges Bank at the 100 to 150 

 meter level in summer (though not farther east), with lower temperatures on the 

 shoaler bottom of the bank, on the one hand, as well as deeper down the slope, on 

 the other. 



