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TABLE OF FORMATIONS

Formation
Era Period or Epoch and thickness Lithology
(feet)
Recent Stream and_ glacier

deposits, felsen-
meer, talus, soil
Cenozoic —_ —_.--
Pleistocene Glacial and glacio-
fluvial deposits

Post-Lower
Cretaceous; Sustut group Conglomerate, sand-
possibly post- stone, shale, coal
Paleocene

Mesozoic
or
Cenozoic Relations not known

Upper Cretaceous or | Sustut group (Sifton | Conglomerate
Paleocene formation)

Relations not known

Lower Cretaceous Uslika formation | Conglomerate, minor
(Aptian) 4,200 argillite

Erosion interval

Granodiorite; adamel-
lite-granite; minor
syenite, syeno-
diorite, pegmatite,
aplite, lampro-
phyre, feldspar
porphyry

Quartz diorite, dior-
ite; minor syeno-
Mesozoic Upper Jurassic or Omineca intrusions diorite, meladior-
Lower Cretaceous ite, amphibolite,

andesite

Hornblendite, appin-
ite, meladiorite,
hornblende diorite;
biotite pyroxenite;
minor feldspathic
pyroxenite, uralite
amphibolite

Intrusive contact

Upper Triassic and_ | Takla group Andesitic flows and
Jurassic +12,000 breccias; minor
basaltic flows; tuff,
agglomerate, shale,
conglomerate, lime-

stone

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