the difference between continuous asymmetric spreading and small-scale 

 discrete jumps of the spreading axis which are too small to be resolv- 

 able with the existing data is largely a matter of semantics. 



There are indications in both the magnetics and seismic data 

 (Fig. 4, profile 4) that the southern limb of intermediate spreading 

 may have extended further to the east. The trough in profile 4 and the 

 apparent "extra" segment of magnetic anomalies seen on this profile may 

 represent a "failed" segment of the intermediate spreading axis. Note 

 that these features are continuous with the SD 2 boundary to the west. 



The final stage of sea-floor spreading in the Caroline Basin also 

 occured west of F.Z, 2 (Fig. 12), It spanned a minimum of 2 m.y. 

 between 12.5 - 14.5 m.y. B.P. The criteria used in the identification 

 of this feature are essentially identical to some of those used by 

 Bracey (1975), with the exception that in this case I can show sym- 

 metry of magnetic anomalies about the proposed spreading axis (Fig 8). 

 As in the case of the intermediate spreading, there are also indica- 

 tions here of asymmetric spreading rates, the northern limb moving 

 more rapidly than the southern. 



While Bracey's (1975) anomaly identifications were in part correct, 

 he erroneously selected the wrong strike direction, partially invali- 

 dating his interpretation. To paraphrase some criteria used in addition 

 to magnetic anomaly identifications by Bracey: (1) The seismic 

 profiles crossing this part (west of F.Z. 2) of the West Caroline Trough 

 (Fig. 4) are dissimilar to those to the east, both in morphology and 

 in sediment thickness. The western profiles show a sediment-free 



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