Volcanic rocks

Massive flows of porphyritic meta-andesite, metabasalt, spilite, and keratophyre, volcanic breccia, and subordinate amounts of fine-grained volcaniclastic rocks. In southwest Oregon includes hornblende, pyroxene, and plagioclase porphyritic andesite flows, breccia, agglomerate, tuff, and locally, some basalt flows and dacitic tuffs of the Applegate Group
State Oregon
Name Volcanic rocks
Geologic age Triassic and (or) Jurassic
Lithologic constituents
Metamorphic > Metaigneous > Metavolcanic > Metaandesite
Metamorphic > Hydrothermally-altered > Spilite
Metamorphic > Metaigneous > Metavolcanic > Metabasalt
Igneous > Volcanic > Mafic-volcanic > Andesite (Flow, Pyroclastic)Includes pyroxene and hornblende andesites
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic-tuff)
Comments Unit is considered possibly correlative with the Hayfork Terrane by Irwin (1994)
NGMDB product
Counties Jackson - Josephine