Table 5.1.

Definition of grain parameters used in modal analyses of sandstones

Q–F–LQ = Qm + Qp, where: Q is total quartz grains; Qm is monocrystalline quartz; and Qp is polycrystalline quartz
F = P + K, where: F is total feldspar grains; P is plagioclase, including albite; and K is potassium feldspar
L = Ls + Lm1 + Lm2 + Lv, where: Ls is total sedimentary lithic fragments (mudstone + shale + siltstone + chert + argillite); Lm1 is total low-grade metamorphic lithic fragments (slate + quartzite); Lm2 is medium-high grade metamorphic lithic fragments (phyllite/schist + phyllitic quartzite + quartz–mica–fcldspar aggregate); and Lv is total volcanic lithic fragments (vitric + lathwork + felsic + microlitic types)
Qm–F–LtQm = monocrystalline quartz
F = total feldspar
Lt = total lithic fragments + polycrystalline quartz
Qp = polycrystalline quartz
Qp–Lvm–LsmLvm = total volcanic and metavolcanic lithic fragment = Lv
Lsm = total sedimentary and metasedimentary lithic fragments = Ls + Lm1 + Lm2
Lm–Lv–LsLm = Lm1 + Lm2
Qp (2–3) = polycrystalline quartz with 2–3 crystals/grain
Qnon = non-undulatory quartz
Qund = Undulatory quartz
Qp(>3) = polycrystalline quartz with >3 crystals/grain