Geologic units containing hornblendite

Hornblendite

A plutonic rock with M equal to or greater than 90 and hbl/(hbl+px+ol) greater than 90%.

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Alabama

Dadeville Complex; Mafic and ultramafic rock (Precambrian to Paleozoic): Mafic and ultramafic rock - ultramafic rock including enstatite pyroxenite, layered actinolite-tremolite amphibolite altered locally to serpentine, anthophyllite, and talc; metanorite; metagabbro; hornblendite; garnet-hornblendite, and massive amphibolite.

Arizona

Jurassic granitic rocks (Jurassic): Granite to diorite, locally foliated and locally alkalic; includes Triassic(?) granitoids in the Trigo Mountains. This unit includes two dominant assemblages of igneous rocks. The Kitt Peak-Trigo Peaks superunit includes, from oldest to youngest: dark, foliated or gneissic diorite, medium-grained equigranular to porphyritic granodiorite, and small, irregular intrusions of light-colored, fine-grained granite. The Ko Vaya superunit, limited to south-central Arizona, includes texturally heterogeneous K-feldspar-rich granitic rocks. (150-180 Ma)
Middle Miocene to Oligocene granitic rocks (Oligocene to Middle Miocene): Granite to diorite representing solidified magma chambers that were the likely source of overlying and nearby volcanic rocks of map unit Tv. The granitic rocks are typically equigranular and fine- to medium-grained. (14-26 Ma)

Idaho

Syenite, quartz syenite, monzodiorite, quartz diorite, gabbro, pyroxenite, and hornblendite; Late Proterozoic plutons; east-central Idaho (Late Proterozoic): Younger or Intermediate Precambrian age intrusive rock undifferentiated.

Massachusetts

Ammonoosuc Volcanics (Middle Ordovician): Ammonoosuc Volcanics - Hornblendite (ultramafic rock).
Belchertown Complex (Devonian): Belchertown Complex (intrudes De) - Hornblendite.
Fourmile Gneiss (Ordovician, Cambrian, or Proterozoic Z): Fourmile Gneiss - Ultramafic hornblendite.
Partridge Formation (Middle Ordovician): Partridge Formation (includes Brimfield Schist of Emerson, 1917) - Lenses of ultramafic rock, commonly hornblendite with or without olivine, orthopyroxene, spinel, cummingtonite, anthophyllite, ilmenite and chlorite.

Maryland

Georgetown Mafic Complex (Late Precambrian (?) - Early Paleozoic ): Georgetown Mafic Complex - Poorly exposed complex of tonalite, dark quartz diorite, gabbro, amphibolite, and undifferentiated basic rocks.

Nevada

Metamorphic rocks (Early Proterozoic): METAMORPHIC ROCKS-Gneiss and schist and lesser amounts of gneissic granite, pyroxenite, hornblendite, migmatite, pegmatite, and marble.

New York

South Carolina

Hammett Grove Meta-igneous Suite - ultramafic rocks (Paleozoic or Neoproterozoic): Hammett Grove Meta-igneous Suite - ultramafic rocks: metamorphosed ultramafic rocks: hornblendite, pyroxenite, serpentinite and talc schist

Texas

Virginia

Garrisonville Mafic Complex (Proterozoic Z-Cambrian): Garrisonville Mafic Complex - Metamorphosed mafic and ultramafic rocks
Georgetown Intrusive Suite (Cambrian): Georgetown Intrusive Suite - Tonalite, quartz gabbro, quartz diorite, metapyroxenite, and hornblendite.
Green Springs Pluton - Diorite and hornblendite. (Proterozoic Y-Pennsylvanian): Green Springs Pluton - Diorite and hornblendite.

Washington

Pre-Tertiary basic intrusive rocks (Triassic-Permian): Predominantly gabbro and metagabbro; includes hornblendite, peridotite, and pyroxenite. In Nighthawk district and near 49th Parallel in Okanogan County and in Orient district of Stevens County.
Tertiary-Cretaceous basic intrusive rocks (Cretaceous-Jurassic): Diorite and gabbro in western Snohomish County.