Figure 11. Mean sand compositions for Sites 974, 976, 977, 978 and 979, and beach samples (Table 2) plotted on QFL and QmFLt ternary diagrams where Q is total monocrystalline and polycrystalline chert; F is total feldspar; L is total lithic fragments including extrabasinal carbonate lithic fragments; Qm is total monocrystalline quartz; and Lt is total lithic fragments including extrabasinal carbonate lithic fragments plus polycrystalline quartz. Arrow indicates likely direction of compositional shift if altered volcaniclastic debris is underestimated in middle Miocene samples from Site 976. Compositional fields from Dickinson et al. (1983): CI = craton interior; TC = transitional continental; BU = basement uplift; RO = recycled orogenic; DA = dissected arc; TA = transitional arc; UA = undissected arc; QR = quartzose recycled; TR = transitional recycled; LR = lithic recycled.

Figure 11. Mean sand compositions for Sites 974, 976, 977, 978 and 979, and beach samples (Table 2) plotted on QFL and QmFLt ternary diagrams where Q is total monocrystalline and polycrystalline chert; F is total feldspar; L is total lithic fragments including extrabasinal carbonate lithic fragments; Qm is total monocrystalline quartz; and Lt is total lithic fragments including extrabasinal carbonate lithic fragments plus polycrystalline quartz. Arrow indicates likely direction of compositional shift if altered volcaniclastic debris is underestimated in middle Miocene samples from Site 976. Compositional fields from Dickinson et al. (1983): CI = craton interior; TC = transitional continental; BU = basement uplift; RO = recycled orogenic; DA = dissected arc; TA = transitional arc; UA = undissected arc; QR = quartzose recycled; TR = transitional recycled; LR = lithic recycled.