Figure F11. Comparison of downhole variation of the ratios of siliciclastic and volcaniclastic grains for all the northern sites (see Table T1 for further information). Q = total quartzose grains, F = total feldspar grains, Lv = total volcanic grains, Lm = total metamorphic lithic grains, Biot = biotite, Musc = muscovite, Cpyx = clinopyroxene, Hnbld = hornblende, Other = actinolite, epidote, sphene, zircon, olivine, opaque minerals (e.g., pyrite, magnetite, and chromite), limonite, prehnite, and pumpellyite.