CONCLUSIONS

Sand recovered on ODP Leg 149 is predominantly quartzofeldspathic with a lesser metamorphic and sedimentary lithic component.

There appears to be a distinct link between grain size and composition within the Cenozoic samples, probably because of a combination of transport and depositional history. Fine sand detrital modes reflect the overall passive margin, rift-to-drift evolution and show a crude basement unroofing trend from the Mesozoic to the Cenozoic. The detrital modes of Cenozoic very fine sand are a function, to some degree, of a superposed compressional tectonic event that resulted in a minor increase in metamorphic lithic content during the Oligocene and Miocene, perhaps associated with enhanced uplift(?) on the adjacent Iberia Peninsula.

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