Page 65 - Introduction to Mineral Exploration

48 A.M. EVANS & C.J. MOON

Sn greisen 15c
(Low-sulfide Au-quartz vein) (36a)
(Homestake Au) (36c)
Anorthosite intrusions
(Anorthosite Ti) (7b)

E. Porphyroaphanitic intrusions present
High-silica granites and rhyolites
Climax Mo 16
(Fluorspar deposits) (26b)
Other felsic and mafic rocks including alkalic
Porphyry Cu 17
Wallrocks are calcareous
Deposits near contact
Porphyry Cu, skarn-related 18a
Cu skarn 18b
Zn-Pb skarn 18c
Fe skarn 18d
Carbonate-hosted asbestos 18e
Deposits far from contact
Polymetallic replacement 19a
Replacement Mn 19b
(Carbonate-hosted Au) (26a)
Wallrocks are coeval volcanic rocks
In granitic rocks in felsic volcanics
Porphyry Sn 20a
Sn-polymetallic veins 20b
In calcalkalic or alkalic rocks
Porphyry Cu-Au 20c
(Epithermal Mn) (25g)
Wallrocks are older igneous and sedimentary rocks
Deposits within intrusions
Porphyry Cu-Mo 21a
Porphyry Mo, low-F 21b
Porphyry W 21c
Deposits within wallrocks
Volcanic hosted Cu-As-Sb 22a
Au-Ag-Te veins 22b
Polymetallic veins 22c
(Epithermal quartz-alunite Au) (25e)
(Low-sulfide Au-quartz vein) (36a)

Extrusive rocks

F. Mafic extrusive rocks
Continental or rifted craton
Basaltic Cu 23
(Sediment-hosted Cu) (30b)
Marine, including ophiolite-related
Cyprus massive sulfide 24a