SECT. 3] 



CROSS-CORRELATION OF DEEP-SEA SEDIMENT CORES 



841 



percentage of fine fraction averages 65%. This is about normal for foraminiferal 

 lutites in the North' Atlantic. Apparently horizontal transportation of sediment 

 has had a negligible effect at station A 164-44. In sharp contrast is the corres- 

 ponding zone in core A 173-4 from the northeast flank of the mount. Here the 

 percentage of fine fraction in most samples exceeds 99%. Evidently this station 

 received much fine material from the top of the mount during the latter part of 

 the last ice age. From this we infer that the general direction of deep circulation 



Muir Seamount 

 33°45'N, 62°35'W , 



I5km 



Possible deep 



current dtrecliun 

 during Fiexuosa 

 nterval of warm 

 climate 



1460 m 



AI64-44 AI73-4 



1007. Left IO0%Right Left 

 Worm Cold W 



Right 

 C 



> Coiling of 

 Globorotalia 

 truncatulinoldes 



AI64-44 AI73-4 



Fine Fraction: < JAjj. 

 0% I007o 0% 



100% 



Fig. 5. The Muir Seamount cores. 



in the region of the Muir seamount during the last ice age must have been from 

 southwest to northeast. However, within the fiexuosa zone of core A173-4 the 

 coarse fraction reaches 90%, a value which can only be explained by current 

 scour winnowing. Thus, the direction of deep circulation must have been quite 

 different during the time of relatively warm climate represented by the fiexuosa 

 zone. To account for current scour at this station, A 172-4, it is necessary to 

 suppose that the direction of deep circulation was parallel to the long axis of 

 the seamount. The fact that the percentage of coarse fraction in the fiexuosa 

 zone of core A 164-44 is normal for the depth of water suggests that the direction 



