Detrital modes were determined for 11 samples from Site 974 (Table 2): eight from Unit I (Pleistocene) and three from Unit III (late Miocene). The Unit I samples are subdivided into resedimented ash and sand end-members. As shown in Figure 6, the Unit I sand has intermediate QFL and QmKP proportions, and for the most part, the lithic fraction is dominated by metamorphic components. In contrast, the Unit I resedimented ash samples are dominantly composed of volcaniclastic lithic fragments. One of the Unit III samples is similar in composition to the Unit I sand. The other two Unit III sand samples are quartzolithic with minor feldspar and a dominantly sedimentary lithic component.
Detrital modes were determined for 13 samples from Site 976: three from Unit I (Pleistocene), six from Unit II (Pliocene to Pleistocene), one from Unit III (lower Pliocene), and three from Unit IV (upper Miocene). As displayed in Figures 7-9, these samples form three compositional groups. Sand within Unit I is quartzose with a minor sedimentary lithic component. Unit II and III sand samples are quartzolithic with a dominantly metamorphic and lesser sedimentary lithic component. The Unit IV samples are feldspathic and characterized by a high proportion of plagioclase feldspar and volcanic-lithic components.
Detrital modes were determined for eight samples from Site 977 and three from Site 978: seven from Unit I (Pleistocene-Pliocene) at Site 977, three from Unit I (Pliocene) at Site 978, and one from Unit II (lower Pliocene to Miocene?) at Site 977. Unit I sand samples from both sites show a range in composition that is essentially a function of variation between the proportions of quartz and metamorphic lithic components (Fig. 7, Fig. 8, Fig. 9). The one sample from Unit II contains subequal proportions of quartz, feldspar, and lithic fragments with a moderately high amount of potassium feldspar and metamorphic and sedimentary lithic fragments (Fig. 7, Fig. 8, Fig. 9).
Detrital modes were determined for 10 samples from Unit I (Pleistocene-upper Pliocene) at Site 979. Most samples show a range in composition that is essentially a function of variation between the proportions of quartz and lithic components (Fig. 7, Fig. 8). In terms of their lithic proportions, the samples fall into two groups: one that is relatively enriched in volcanic lithic fragments and a second dominated by sedimentary and metamorphic lithic fragments (Fig. 10).
Detrital modes were determined for 10 sand samples from modern beaches along the Spanish coast. These show a range in composition that is essentially a function of variation between the proportions of quartz, metamorphic lithic fragments, and, to a lesser degree, plagioclase feldspar content (Fig. 7, Fig. 8, Fig. 10). The lithic fraction of one sample is entirely volcaniclastic.