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Geologic units containing gabbroid

Earth material > Plutonic rock
Gabbroid
A plutonic rock with Q < 20% or F < 10%, P/(A+P) > 65%, and pl/(pl+px+ol) between 10 and 90%.
Subtopics:
Quartz monzogabbro
Monzogabbro
Quartz gabbro
Gabbro
Anorthosite

California - Michigan - Montana - Wyoming
California
Miocene marine rocks and Franciscan schist (Cretaceous(?) to Miocene)
Michigan
Metagabbro (Early Proterozoic)
Metagabbro - Mafic to ultramafic bodies defined and delineated principally by positive magnetic and gravity anomalies; includes diorite bodies. Comagmatic with unit Xmi
Montana
Diorite and gabbro (Phanerozoic | Mesozoic | Cretaceous(?))
Diorite and gabbro: dark, moderately fine grained rocks in sills, dikes, and irregular bodies; not readily distinguished from similar rocks of other ages. Hence in the less well-known areas errors in age assignment may remain. These rocks are assigned to the Cretaceous(?).
Stillwater complex (Archean Proterozoic(?) preCambrian-Proterozoic(?) preCambrian(?) Phanerozoic | Paleozoic(?) Mesozoic(?) Cenozoic | Cambrian(?) Ordovician(?) Silurian(?) Devonian(?) Carboniferous(?) Permian(?) Triassic(?) Jurassic(?) Cretaceous(?) Tertiary)
Stillwater complex: consists chiefly of ultrabasic intrusive rocks and metamorphic rocks not yet named or subdivided.
Tertiary dikes and sills (Phanerozoic | Cenozoic | Tertiary)
Tertiary dikes and sills: mostly granophyric rocks in west and alkalic rocks in east, but includes some quartz diorite and other rocks. These dikes and sills are in part offshoots of the Tertiary coarse-grained intrusive rocks.
Wyoming
Mafic intrusive rocks (Proterozoic | Paleoproterozoic )
MAFIC INTRUSIVE ROCKS. Sierra Madre--Gabbro of Elkhorn Mountain; age 1,800 Ma. Medicine Bow Mountains--Mullen Creek 5 and Lake Owens 7 Mafic Complexes; older than 1,700 Ma.

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