Classification - Origin of Potassium-rich Silica-deficient Igneous Rocks - page 83

Mel

Mel

Mel

Mo

Wo

Wo Wo

Mel

Cpx

Italite
Lc Ks Ks Lc

Madupite
Wyomingite Vesbite

Cecilite

Cpx

Cpx

Cpx

Phl

Mel Lc

Phl Phl Lc Qz

Mel Kf

Kf

Mo

Mo

Cpx Cpx

Cpx Cpx

Cpx
Wyomingite
Madupite
Lc

Sanidinite

Vesecite

Alnoite

Kf

Ks Kf

Alaskite
Charnockite

Kf

Kf

Qz

Jumillite

Shonkinite
Cascadite

Orendite

Phl

Hy Hy

Phl Phl Phl

Phl

Ol Ol

Ol Ol Ol

Fig. 3.10 An ' exploded ' view of the subtetrahedra in the modi ed normative tetrahedron of
Fig. 3.9 . The corner of the isolated subtetrahedra are labelled with the names of the modal minerals
most closely represented by the normative minerals, Cpx = Clinopyroxene, Hy = Hypersthese,
Kf = Potassium feldspar, Mel = Melilite, Ol = Olivine, and Phl = phlogopite. The joins, planes and
volumes (underlined) are named for rocks for which the assemblage is most closely representative
(after Yoder 1986)

Fig. 3.11 Subtetrahedra of
Fig. 3.10 from reaction of
phlogopite (Phl) and
potassium feldspar (Kf), to
form olivine + leucite + H 2 O,
illustrating the heteromorphic
relations of
jumillite

Cpx

Cpx

Lc

Lc

Kf

Absarokite

shonkinite to
missourite absarokite (after
Yoder 1986)

-

Missourite
Kajanite

Phl

Ol

Ol