Figure 3 Modal classification of gabbroic rocks

Modal classification of gabbroic rocks based on proportions of plag, ol, opx, cpx, and hbl. leuco- and mela- may be used as adjectives to denote light and dark colored repsectively. a) Gabbroic rocks enriched in plag, px, and ol b) Gabbroic rocks enriched in plag, opx, and cpx c) Gabbroic rocks enriched in plag, px, and hbl

Figure 3

Figure 3

Modal classification of gabbroic rocks based on proportions of plag, ol, opx, cpx, and hbl. leuco- and mela- may be used as adjectives to denote light and dark colored respectively.
a) Gabbroic rocks enriched in plag, px, and ol
b) Gabbroic rocks enriched in plag, opx, and cpx
c) Gabbroic rocks enriched in plag, px, and hbl

Anorthosite

(abc) It contains >90% Plagioclase

Leuco-

adjective used for light colored gabbroic rocks that contain 65-90% Plagioclase

Gabbroids

Group of gabbroic rocks with 35-65% Plagioclase

Mela-

adjective used for dark colored gabbroic rocks that contain 10-35% Plagioclase

Ultramafic rocks

They contain <10% plagioclase

Gabbro, Gabbronorite, Norite

(a) They contain 10-90% Plagioclase, >90% Pyroxene, and <10% Olivine

Troctolite

(a) It contains 35-65% Plagioclase, <10% Pyroxene, and >90% Olivine

Plagioclase-bearing ultramafic rocks

(a) It contains Pyroxene, Olivine, and <10% Plagioclase

Olivine gabbro, Olivine gabbronorite, Olivine norite

(a) They contain Pyroxene, Olivine, and 10-35% Plagioclase

Norite

(b) It contains Plagioclase, >95% Orthopyroxene, and <5% Clinopyroxene

Gabbro

(b) It contains Plagioclase, >95% Clinopyroxene, and <5% Orthopyroxene

Gabbronorite

(b) It contains Plagioclase, 50% Orthopyroxene, and 50% Clinopyroxene

Cpx norite

(b) It contains 50-95% Orthopyroxene, and 5-50% Clinopyroxene

Opx norite

(b) It contains 5-50% Orthopyroxene, and 50-95% Clinopyroxene

Plagioclase-bearing pyroxenite

(b) It contains opx, cpx, and <10% Plagioclase

Horblende gabbro

c) It contains 35-65% Plagioclase, >90% Hornblende, <10% Pyroxene

Px Hbl gabbro, Px Hbl gabbronorite, Px Hbl norite

c) They contain Pyroxene, Hornblende, and 10-35% Plagioclase

Horblende pyroxenite

c) It contains <10% Plagioclase, 10-50% Hornblende, and 50-90% Pyroxene

Pyroxene hornblendite

c) It contains <10% Plagioclase, 50-90% Hornblende, and 10-50% Pyroxene

Plagioclase-bearing pyroxenite

c) It contains <10% Plagioclase, >90% Pyroxene, and <10% Hornblende

Plagioclase-bearing hornblendite

c) It contains <10% Plagioclase, >90% Hornblende, and <10% Pyroxene