Table 1. Categories of detrital grains included in petrographic point counts of turbidite sand.

Table 1. Categories of detrital grains included in petrographic point counts of turbidite sand.

Categories of detrital grains

Modal constituents:

Q = total quartz = Q_m + Q_p

Q_m = monocrystalline quartz

Q_p = polycrystalline quartz = microcrystalline + cryptocrystalline

F = total feldspar = P + K

P = plagioclase

K = K-feldspar = orthoclase + perthite

L = unstable lithic fragments = L_s + L_v + L_m

L_s = sedimentary = claystone + mudstone + siltstone

L_v = volcanic = mafic (basaltic) + intermediate (andesitic) + silicic (rhyolitic)

L_m = metamorphic = quartz-mica tectonite + slate-phyllite

L_sm = sedimentary + metasedimentary

L_t = total polycrystalline fragments = L + Q_p

Accessory constituents:

Heavy minerals = opaque + non-opaque

Mica = muscovite + biotite

Biogenic = fossil fragments + sparry calcite

Other = trace constituents + altered grains + unknown