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Geologic units containing diorite

Arizona

Early Proterozoic granitic rocks (Early Proterozoic)

Wide variety of granitic rocks, including granite, granodiorite, tonalite, quartz diorite, diorite, and gabbro. These rocks commonly are characterized by steep, northeast-striking foliation. (1600-1800 Ma)

Early Proterozoic metamorphic rocks (Early Proterozoic)

Undivided metasedimentary, metavolcanic, and gneissic rocks. (1600-1800 Ma)

Early Proterozoic metasedimentary rocks (Early Proterozoic)

Metasedimentary rocks, mostly derived from sandstone and shale, with minor conglomerate and carbonate rock. Includes quartz-rich, mostly nonvolcanic Pinal Schist in southeastern Arizona and variably volcanic-lithic sedimentary rocks in the Yavapai and Tonto Basin supergroups in central Arizona. (1600-1800 Ma)

Early Proterozoic metavolcanic rocks (Early Proterozoic)

Weakly to strongly metamorphosed volcanic rocks. Protoliths include basalt, andesite, dacite, and rhyolite deposited as lava or tuff, related sedimentary rock, and shallow intrusive rock. These rocks, widely exposed in several belts in central Arizona, include metavolcanic rocks in the Yavapai and Tonto Basin supergroups. (1650 to 1800 Ma)

Early Tertiary to Late Cretaceous granitic rocks (Late Cretaceous to Early Tertiary)

Porphyritic to equigranular granite to diorite emplaced during the Laramide orogeny. Larger plutons are characteristically medium-grained, biotite +/- hornblende granodiorite to granite. Smaller, shallow-level intrusions are typically porphyritic. Most of the large copper deposits in Arizona are associated with porphyritic granitic rocks of this unit, and are thus named 'porphyry copper deposits'. (50-82 Ma)

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)

Middle Miocene to Oligocene volcanic rocks (Oligocene to Middle Miocene)

Lava, tuff, fine-grained intrusive rock, and diverse pyroclastic rocks. These compositionally variable volcanic rocks include basalt, andesite, dacite, and rhyolite. Thick felsic volcanic sequences form prominent cliffs and range fronts in the Black (Mohave County), Superstition, Kofa, Eagletail, Galiuro, and Chiricahua Mountains. This unit includes regionally extensive ash-flow tuffs, such as the Peach Springs tuff of northwestern Arizona and the Apache Leap tuff east of Phoenix. Most volcanic rocks are 20-30 Ma in southeastern Arizona and 15 to 25 Ma in central and western Arizona, but this unit includes some late Eocene rocks near the New Mexico border in east-central Arizona. (11-38 Ma)

Middle Proterozoic granitic rocks (Middle Proterozoic)

Mostly porphyritic biotite granite with large microcline phenocrysts, with local fine-grained border phases and aplite. Associated pegmatite and quartz veins are rare. This unit forms large plutons, including the Oracle Granite, Ruin Granite, granite in the Pinnacle Peak - Carefree area northeast of Phoenix, and several bodies west of Prescott. (1400-1450 Ma)

Orocopia Schist (Late Cretaceous to Early Tertiary)

Mostly gray, fine-grained quartz-feldspar-mica schist, with sparse metabasalt and metachert. The unit is exposed in tectonic windows in the southwestern corner of Arizona. It is interpreted as metamorphosed marine sandstone that was tectonically emplaced beneath southwestern Arizona during early Tertiary subduction of Pacific Ocean sea floor. (65-165 Ma)

Proterozoic granitic rocks (Proterozoic)

Undivided Early and Middle Proterozoic granitic rocks (units Xg and Yg). (1400-1800 Ma)

Tertiary to Early Proterozoic gneissic rocks (Early Proterozoic to Tertiary)

Gneissic rocks with complex histories, typically with well developed, light-colored granitoid layers and dark-colored biotite- and amphibole-rich layers. Protoliths are of Tertiary to Proterozoic age. This unit includes variably mylonitic gneisses in metamorphic core complexes that have been exhumed from middle crustal levels by large-displacement middle Tertiary normal faults, and gneiss exposed at scattered locations near the Colorado River in southwestern Arizona. These rocks are interpreted to record Proterozoic, Mesozoic, and Tertiary metamorphism and deformation. (15-1800 Ma)

California

Cenozoic (Tertiary) granitic rocks, unit 1 (Death Valley) (middle to late Miocene)

Cenozoic (Tertiary) granitic rocks--quartz monzonite, quartz latite, and minor monzonite, granodiorite, and granite; found in the Kingston, Panamint, Amargosa, and Greenwater Ranges in southeastern California.

Mesozoic gabbroic rocks, unit 1 (Trinity Ophiolite) (Ordovician)

Gabbro and dark dioritic rocks; chiefly Mesozoic

Mesozoic gabbroic rocks, unit 2 (undivided) (Triassic to Cretaceous)

Gabbro and dark dioritic rocks; chiefly Mesozoic

Mesozoic granitic rocks (?) (Jurassic(?))

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite(?) (Northern Klamath Mountains)

Mesozoic granitic rocks, unit 1 (Salinian Block) (Early to Late Cretaceous)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Mesozoic granitic rocks , unit 2 (Peninsular Ranges) (Middle Jurassic to Late Cretaceous)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Mesozoic granitic rocks, unit 3 (Sierra Nevada, Death Valley area, Northern Mojave Desert and Transverse Ranges) (Permian to Tertiary; most Mesozoic)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Mesozoic granitic rocks, unit 4 (Klamath Mountains and Northern Sierra Nevada) (Devonian)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Mesozoic granitic rocks, unit 5 (Klamath Mountains) (Jurassic to early Cretaceous)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Mesozoic granitic rocks, unit 6 (Eastern Klamath Mountains) (Permian)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

Paleozoic and Permo-Triassic granitic rocks, unit 1 (Eastern Klamath Mountains) (Permian)

Paleozoic and Permo-Triassic granitic rocks in the San Gabriel and Klamath Mountains

Paleozoic and Permo-Triassic granitic rocks unit 2 (San Gabriel Mountains) (Late Triassic)

Paleozoic and Permo-Triassic granitic rocks in the San Gabriel and Klamath Mountains

Precambrian granitic rocks (?), (Death Valley) (Miocene)

Precambrian granite, syenite, anorthosite, and gabbroic rocks in the San Gabriel Mountains; also various Precambrian plutonic rocks elsewhere in southeastern California(?)

Precambrian granitic rocks, unit 1 (Eastern Mojave Desert) (Early Proterozoic to Miocene)

Precambrian granite, syenite, anorthosite, and gabbroic rocks in the San Gabriel Mountains; also various Precambrian plutonic rocks elsewhere in southeastern California

Precambrian granitic rocks, unit 4, (Death Valley) (Miocene)

Precambrian granite, syenite, anorthosite, and gabbroic rocks in the San Gabriel Mountains; also various Precambrian plutonic rocks elsewhere in southeastern California

Precambrian igneous and metamorphic rock complex (Early Proterozoic to Miocene)

Complex of Precambrian igneous and metamorphic rocks. Mostly gneiss and schist intruded by igneous rocks; may be Mesozoic in part.

Schist of various types and ages, unit 3 (Santa Cruz Island) (Jurassic)

Schists of various types; mostly Paleozoic or Mesozoic age; some Precambrian.

Colorado

Mafic rocks of 1700-m.y. age group (Proterozoic | Paleoproterozoic)

Gabbro and mafic diorite and monzonite

Connecticut

Dioritic phase [of Preston Gabbro] (Middle Ordovician or older)

Dioritic phase [of Preston Gabbro] - Medium- to dark-gray, streaked or speckled, medium-grained diorite and quartz diorite, gneissic where sheared near contact, composed of plagioclase, hornblende, and biotite, and locally quartz and relic pyroxene.

Idaho

Amphibolite after gabbro, diabase, and diorite; Middle Proterozoic sill-like intrusions; southern and northern Belt provinces (Middle Proterozoic)

Younger or Intermediate Precambrian age intrusive rock undifferentiated; Intrusive rock of eastern Idaho; appears older than Cretaceous, possibly Precambrian; Highly metamorphosed rock of central Idaho; age and origin of rock questionable.

Basalt, andesite, diorite, lamprophyre intrusions; Tertiary to Cretaceous, undivided; northern Idaho, central Idaho (Cretaceous or Eocene)

Eocene intrusions including large granitic plutons and dike swarms of central Idaho

Diorite, gabbro, and granite; Jurassic to Triassic plutons; western Idaho, Blue Mountains island-arc complex (Jurassic to Triassic)

Lower Mesozoic intrusions; localized near the Snake Canyon of western Idaho.

Gabbro, diorite, amphibolite, lamprophyre; Tertiary to Late Proterozoic, undivided; northern Idaho (Tertiary to Late Proterozoic)

Younger Precambrian dioritic and amphibolitic sills of northern Idaho.

Gabbro, diorite, quartz diorite, aplite; Late to Middle Proterozoic sills injected into sedimentary strata of the Belt Basin; northern Belt province (Late to Middle Proterozoic)

Younger Precambrian dioritic and amphibolitic sills of northern Idaho; basaltic or mafic; as gabbro.

Granodiorite, quartz monzonite, granite, alaskite, quartz monzodioirte, diorite; Tertiary to Cretaceous, intrusions, undivided; northern, west-central, and southwestern Idaho (Eocene to Cretaceous)

Eocene intrusions; Cretaceous plutons, intermediate, Cretaceous plutons, felsic; metamorphosed granitic intrusive rock

Intermediate intrusions; mostly Late Cretaceous dioritic to granodioritic plutons of the Idaho batholithic assemblage (Cretaceous)

Cretaceous plutons; intermediate; as granodiorite or diorite; probably includes unmapped older and younger crystalline bodies.

Intrusive andesite, basalt, and diorite; Quaternary to Pliocene subvolcanic intrusions; southeastern Idaho (Quaternary to Pliocene)

Intrusive rocks: mostly Late Cretaceous granodioritic to granitic plutons of the Idaho batholithic assemblage, but including some Eocene intrusions; northern Idaho and Atlanta batholith (Cretaceous to Eocene)

Cretaceous plutons; probably includes unmapped older and younger crystalline bodies.

Metamorphosed granodiorite, quartz monzonitek tonalite, quartz diorite; mostly Cretaceous orthogneiss and migmatite; northern and Atlanta batholith; margins of Bitterroot and Atlanta batholiths (Cretaceous)

Metamorphosed granitic intrusive rock; associated with pluton margins and stress areas.

Monzogranite, granodiorite, syenite, monzodiorite, monzonite, and diorite; Eocene phaneritic to porphyro-aphanitic intrusions (subunits are Teif and Teii); northern Idaho to central Idaho (Eocene)

Eocene intrusions including large granitic plutons and dike swarms of central Idaho

Quartz diorite, tonalite, granodiorite, orthogneiss, migmatite; Cretaceous to Jurassic quartz dioritic plutons; western Idaho, Blue Mountains island-arc complex (Early Cretaceous to Late Jurassic)

Lower Cretaceous to Upper Jurassic intrusions in west-central Idaho.

Quartz monzodiorite, monzogranite, granodiorite, monzonite, diorite; Eocene phaneritic to porphyro-aphanitic intrusions of the quartz monzodiorite suite; Challis magmatic belt (Eocene)

Eocene intrusions of intermediate (mafic to felsic) composition

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

Biotite-hornblende diorite and quartz-bearing diorite (Devonian)

Biotite-hornblende diorite and quartz-bearing diorite - Mostly foliated; intrudes Dl.

Biotite-hornblende mafic dikes (Proterozoic Z)

Biotite-hornblende mafic dikes - Locally with relict subophitic texture. Intrudes Yw and Ygg.

Dedham Granite (Proterozoic Z)

Dedham Granite - Light grayish-pink to greenish-gray, equigranular to slightly porphyritic, variably altered, granite south and west of Boston. Includes dioritic rock near Scituate and Cohasset and Barefoot Hills Quartz Monzonite of Lyons (1969) and Lyons and Wolfe (1971). Intrudes Zdi, Zgb, Zb, Zv. Extensive calc-alkaline plutons separated by Boston basin have long been mapped as Dedham. Those to the north of Boston and studied in this report, are referred to as Dedham North. Crystallization ages for the Dedham North suite (based on titanites and zircons) have been determined at 607+/-4 Ma, while ages for the Lynn are slightly younger at 596+/-3 Ma. Both are clearly part of the Late Proterozoic magmatic event. Dates on two samples from Sheffield Heights indicate that the diorite and granite are part of the Dedham North suite. The Dedham south and west of Boston has been dated at 630+/15 Ma (Zartman and Naylor, 1984). Dedham North Granite has a compositionally highly variable suite ranging from leucogranites to granodiorites, tonalites, and quartz diorite. The granites originated by partial melting of a sedimentary protolith, while the intermediate members show a mixing of granitic magma and mafic magma (Hepburn and others, 1993).

Diorite (Proterozoic Z)

Diorite - Medium-grained hornblende diorite metamorphosed in part to amphibolite and hornblende gneiss.

Diorite and gabbro (Proterozoic Z)

Diorite and gabbro - Complex of diorite and gabbro, subordinate metavolcanic rocks and intrusive granite and granodiorite.

Diorite and tonalite (Devonian and Silurian)

Diorite and tonalite - Includes Dracut Diorite, tonalite near the Ayer Granite, and equivalents of the Exeter Diorite of New Hampshire; intrudes Sb.

Diorite at Goff Ledges (Ordovician)

Diorite at Goff Ledges - Diorite at Goff Ledges (Ogd) and similar diorite (Od) in the Windsor quadrangle. Very coarse-grained to pegmatitic, slightly foliated hornblende-plagioclase diorite, minor hornblende pyroxenite. Ogd intrudes CAZh and CAZhk. Od intrudes the Rowe Schist of the Rowe-Hawley zone.

Diorite at Goff Ledges (Ordovician)

Diorite at Goff Ledges - Diorite at Goff Ledges (Ogd) and similar diorite (Od) in the Windsor quadrangle. Very coarse-grained to pegmatitic, slightly foliated hornblende-plagioclase diorite, minor hornblende pyroxenite. Ogd intrudes CAZh and CAZhk. Od intrudes the Rowe Schist of the Rowe-Hawley zone.

Diorite at Rowley (Proterozoic Z)

Diorite at Rowley - Dark, green-gray, medium-grained hornblende diorite.

Fine-grained hornblende diorite (Precambrian to Paleozoic)

Fine-grained hornblende diorite - In Connecticut River bed, near French King Rock.

Meladiorite and norite (Devonian)

Meladiorite and norite - Weakly to moderately foliated; intrudes Dl.

Metamorphosed mafic to felsic flow, and volcaniclastic and hypabyssal intrusive rocks (Proterozoic Z)

Metamorphosed mafic to felsic flow, and volcaniclastic and hypabyssal intrusive rocks - Includes some diorite and gabbro north and northwest of Boston.

Nahant Gabbro and gabbro at Salem Neck (Ordovician)

Nahant Gabbro and gabbro at Salem Neck - Labradorite-pyroxene gabbro, hornblende gabbro and hornblende diorite. Intrudes CAbw. Nahant Gabbro intrudes Early Cambrian Weymouth Formation at Nahant and thus is younger than gabbroic or dioritic rocks intruded by Late Proterozoic Dedham Granite or Topsfield Granite. Unrecognized equivalents to Nahant Gabbro at Nahant and at Salem Neck may be present within unnamed gabbro and diorite units shown on MA State geologic map (Zen and others, 1983). Mapped as three facies at Nahant, following usage of Bell (1977): pyroxene gabbro, olivine gabbro, and quartz diorite. Biotite from olivine gabbro was analyzed by Rb-Sr and K-Ar methods and yielded an Ordovician age (450 +/-13 Ma by Rb-Sr methods, 483 +/-21 Ma by K-Ar methods). Quartz diorite phase may be a more mafic phase of Dedham Granite (Wones and Goldsmith, 1991).

Sharpners Pond Diorite (Silurian)

Sharpners Pond Diorite - Non-foliated, medium-grained equigranular biotite-hornblende tonalite and diorite. Intrudes Soagr, OZn, OZf.

Straw Hollow Diorite and Assabet Quartz Diorite undifferentiated (Silurian)

Straw Hollow Diorite and Assabet Quartz Diorite undifferentiated - Gray, medium-grained, slightly-foliated biotite-hornblende diorite and quartz diorite. Intrudes OZn.

Maryland

Port Deposit Gneiss (Paleozoic)

Port Deposit Gneiss - Moderately to strongly deformed intrusive complex composed of gneissic biotite quartz diorite, hornblende-biotite quartz diorite, and biotite granodiorite; all rocks foliated and some strongly sheared; age 550 +/- 50 m.y. * by radiogenic dating.

Maine

Cambrian gabbro/diorite/ultramafic rocks (Cambrian)

Cambrian gabbro/diorite/ultramafic rocks

Carboniferous gabbro/diorite/ultramafic rocks (Carboniferous)

Carboniferous gabbro/diorite/ultramafic rocks undivided

Cretaceous gabbro/diorite/ultramafic rocks (Cretaceous)

Cretaceous gabbro/diorite/ultramafic rocks

Cretaceous quartz diorite - gabbro/diorite/ultramafic rocks (Cretaceous)

Cretaceous quartz diorite - gabbro/diorite/ultramafic rocks - Cretaceous biotite quartz diorite and gabbro/diorite/ultramafic rocks

Devonian diorite (Devonian)

Devonian diorite - biotite diorite

Devonian gabbro/diorite/ultramafic rocks (Devonian)

Devonian gabbro/diorite/ultramafic rocks

Devonian gabbro/diorite/ultramafic rocks - quartz diorite (Devonian)

Devonian gabbro/diorite/ultramafic rocks - quartz diorite - Devonian gabbro/diorite/ultramafic rocks to biotite quartz diorite - gabbro, diorite, ultramafic rocks, biotite monzodiorite, biotite syenite, and biotite quartz diorite.

Devonian granite-quartz diorite (Devonian)

Devonian granite-quartz diorite: biotite granite, biotite granodiorite, biotite tonalite, biotite quartz syenite, biotite quartz monzodiorite, and biotite quartz diorite.

Devonian granodiorite - quartz diorite (Devonian)

Devonian granodiorite - quartz diorite - Devonian biotite granodiorite to biotite quartz diorite - biotite granodiorite, biotite tonalite, biotite quartz syenite, biotite quartz monzodiorite, and biotite quartz diorite.

Devonian granodiorite - quartz monzodiorite (hornblende accessory mineral) (Devonian)

Devonian granodiorite - quartz monzodiorite (hornblende accessory mineral) - Devonian hornblende-biotite granodiorite to quartz monzodiorite - hornblende-biotite granodiorite, hornblende-biotite tonalite, hornblende-biotite quartz syenite, and hornblende-biotite quartz monzodiorite.

Mesozoic gabbro/diorite/ultramafic rocks (Mesozoic)

Mesozoic gabbro/diorite/ultramafic rocks

Ordovician gabbro/diorite/ultramafic rocks (Ordovician)

Ordovician gabbro/diorite/ultramafic rocks

Silurian gabbro/diorite/ultramafic rocks (Silurian)

Silurian gabbro/diorite/ultramafic rocks

Michigan

Granitic rocks (Early Proterozoic)

Granitic rocks - Gray to pinkish-gray, mottled, medium-grained syenite, granite, and granodiorite. Moderately strong propylitic alteration and weak cataclasis. Forms small bodies south of Crystal Falls, MI (James and others, 1968). A body near Tobin Location has a U-Pb concordia intercept age of 1840 +/-5 Ma (Z.E. Peterman, written communication, 1988). Includes porphyritic red granite that intrudes Lake Archean Dickinson Group - Red mylonitic gneissic granite (about 1970 Ma).

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

Minnesota

Gabbro, diorite, peridotite, and associated komatiitic flows of the Deer Lake sequence in Itasca County and the upper part of the Newton Lake Formation in Lake and St. Louis Counties (Late Archean)

Gabbro, diorite, peridotite, and associated komatiitic flows of the Deer Lake sequence in Itasca County and the upper part of the Newton Lake Formation in Lake and St. Louis Counties

Multiphase intrusions of hornblende-pyroxene-bearing and biotite-bearing monzonite, monzodiorite, diorite, syenite, and granodiorite (Late Archean)

Multiphase intrusions of hornblende-pyroxene-bearing and biotite-bearing monzonite, monzodiorite, diorite, syenite, and granodiorite - Typically postdates regional metamorphism and deformation associated with the Algoman orogen.

Post-tectonic intrusions of the Penokean orogen (Early Proterozoic)

Post-tectonic intrusions of the Penokean orogen - Small stocks of olivine pyroxenite in Morrison County; small plutons of hornblende-rich diorite and gabbro that contain layers and lenses of nelsonite, pyroxenite, and anorthosite in Todd County.

Missouri

DIABASE DIKES AND SILLS (Precambrian [Y])

DIABASE DIKES AND SILLS

Montana

Boulder batholith and broadly related stocks (Phanerozoic | Cenozoic | Tertiary Cretaceous)

Boulder batholith and broadly related stocks: mainly quartz monzonite, but includes diorite, aplite, and other rocks. The distinctions between masses relative to the Boulder batholith and those mapped as of other ages are locally arbitrary and tentative.

Diabase, metagabbro, and diorite and related rocks (Proterozoic)

Diabase, metagabbro, and diorite and related rocks: dark gray fine to medium grained, mostly in dikes and sills; dominantly mafic but contain alkalai feldspar and micropegmatite in some areas.

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(?).

North Carolina

Amphibolite (Cambrian/Late Proterozoic)

Amphibolite - equigranular, massive to well foliated, dioritic to basaltic dikes and sills; variably metamorphosed.

Amphibolite (Cambrian/Late Proterozoic)

Amphibolite - equigranular, massive to well foliated, dioritic to basaltic dikes and sills; variably metamorphosed.

New Hampshire

Augite-hornblende diorite and gabbro (Cretaceous )

Augite-hornblende diorite and gabbro - Gray to black, coarse-grained, porphyritic. Found in Mt. Pawtuckaway quadrangle.

Diorite (Jurassic)

Diorite - Contains hornblende, biotite, and hedenbergite.

Exeter Diorite (Early Devonian)

Exeter Diorite - Includes associated intrusive rocks of southeastern New Hampshire; pyroxene and pyroxene-hornblende diorite and gabbro, along with minor granodiorite and granite.

Hornblende-biotite quartz monzodiorite (Jurassic)

Hornblende-biotite quartz monzodiorite - Composition ranges from quartz monzonite to diorite.

Hornblende diorite (Cretaceous )

Hornblende diorite - Coarse-grained to porphyritic.

Hornblende granodiorite of Highlandcroft pluton (Late Ordovician)

Hornblende granodiorite of Highlandcroft pluton - Contains minor tonalite and diorite.

Hypersthene-biotite quartz diorite and hornblende or actinolite diorite or gabbro (Early Devonian - Late Devonian)

Hypersthene-biotite quartz diorite and hornblende or actinolite diorite or gabbro - Spatially associated with Spaulding Tonalite plutons.

Kinsman Granodiorite (Early Devonian )

Kinsman Granodiorite - (Kinsman Quartz Monzonite of Billings, 1955) - Foliated granite, granodiorite, tonalite, and minor quartz diorite; large megacrysts of potassium feldspar characteristic; garnet locally abundant.

Porphyritic hornblende diorite (Jurassic)

Porphyritic hornblende diorite - Found in northwestern New Hampshire.

Rye Complex (Ordovician? - Late Proterozoic?)

Rye Complex - Migmatite of gray, foliated, sheared or mylonitized two-mica granite and pegmatite, minor hornblende-biotite diorite, intruding metapelites and metavolcanic rocks in southeastern New Hampshire.

Spaulding Tonalite (Early Devonian)

Spaulding Tonalite (Spaulding Quartz Diorite of Fowler-Billings, 1949) - Weakly foliated to nonfoliated, spotted biotite quartz diorite, tonalite, granodiorite, and granite; garnet and muscovite may or may not be present.

Tonalite, diorite, granodiorite, and granite (Late Ordovician )

Tonalite, diorite, granodiorite, and granite - More mafic rocks have hornblende; part of Lost Nation pluton.

Winnipesaukee Tonalite (Early Devonian)

Winnipesaukee Tonalite (Winnipesaukee Quartz Diorite of Billings, 1955) - Gray, massive to foliated tonalite and minor quartz diorite, granodiorite, and granite. Probably coeval with Spaulding Tonalite.

New Jersey

Diorite (Middle Proterozoic)

Diorite - Gray- to tan-weathering, greenish-gray to brownish-gray, medium- to coarse-grained, greasy-lustered, massive diorite containing andesine or oligoclase, clinopyroxene, hornblende, hypersthene, and sparse amounts of biotite and magnetite. Amphibolite layers common.

Hornblende Syenite (Middle Proterozoic)

Hornblende Syenite - Tan- to buff-weathering, pinkish-gray or greenish-gray, medium- to coarse-grained, gneissoid syenite and lesser amounts of quartz syenite containing microcline microperthite, oligoclase, quartz, and hornblende. Some phases are monzonite or monzodiorite.

Pyroxene Granite (Middle Proterozoic)

Pyroxene Granite - Gray- to buff- or white-weathering, greenish-gray, medium- to coarse-grained, massive, gneissoid to indistinctly foliated granite containing mesoperthite to microantiperthite, quartz, oligoclase, and clinopyroxene. Common accessory minerals include titanite, magnetite, apatite, and trace amounts of pyrite. Some phases are monzonite, quartz monzodiorite, or granodiorite. Locally includes small bodies of amphibolite not shown on map.

New Mexico

mafic dikes, diabase, metadiabase, metadiorite (Proterozoic | Mesoproterozoic)

Middle Proterozoic; mafic dikes, diabase, metadiabase, metadiorite mainly of Burro Mountains; age not well constrained

mafic dikes, upper Proterozoic (Proterozoic | Neoproterozoic)

Upper Proterozoic; mafic dikes

Nevada

Diorite (Jurassic to Cretaceous)

Granitic rocks (Middle Triassic to Early Jurassic)

GRANITIC ROCKS-Quartz monzonite in northern Esmeralda County

Granitic rocks (Jurassic)

GRANITIC ROCKS-Mostly quartz monzonite and granodiorite

Granitic rocks, western Nevada (Jurassic to Cretaceous)

GRANITIC ROCKS, WESTERN NEVADA (Mesozoic)-Mostly quartz monzonite and granodiorite. Inconclusively dated or not dated radiometrically

Intrusive rocks (Late Cretaceous to Middle Miocene)

INTRUSIVE ROCKS-Aphanitic, porphyritic, and coarsely granular rocks ranging in composition from diorite to granite. Clark County

Intrusive rocks of mafic to intermediate composition (Eocene to Miocene)

INTRUSIVE ROCKS OF MAFIC TO INTERMEDIATE COMPOSITION

Shale and thin-bedded or laminated limestone; also thinly interbedded limestone and chert (Middle Cambrian to Late Cambrian)

SHALE AND THIN-BEDDED OR LAMINATED LIMESTONE; ALSO THINLY INTERBEDDED LIMESTONE AND CHERT-Includes units such as Preble and Emigrant Formations

New York

Diorite with hornblende and/or biotite (Upper Ordovician)

Diorite with hornblende and/or biotite.

Gabbro or norite to hornblende diorite (Upper Ordovician)

Gabbro or norite to hornblende diorite - rock complex with minor pyroxenite; Croton Falls and Peach Lake complexes in New York, and Mt. Prospect Complex in Connecticut.

Oklahoma

Carlton Rhyolite Group (Phanerozoic | Paleozoic | Cambrian-Middle)

CLINTON- Rhyolite flows and tuffs; about 4,500 feet thick; one outlier is shown in southern part of mapped area. LAWTON- Rhyolite flows, tuffs, conglomerate beds, and diabase sills; thickness, 4,500 feet (1,370 m).

Diorite Sill (Phanerozoic | Paleozoic | Ordovician-Late(?))

McALESTER TEXARKANA- Diorite, light-greenish-gray, medium- to fine-grained, quartz-free, with much andesine plagioclase and ferromagnesian minerals altered to chlorite and limonite; occurs in sections 10 and 15, Township 5 South, Range 23 East, in Womble Formation, striking North, 45 degrees East and dipping 10 degrees to 20 degrees Northwest; thickness, 2 to 10 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS

Raggedy Mountain Gabbro Group (Phanerozoic | Paleozoic | Cambrian-Early)

LAWTON- Gabbro, anorthosite, and diorite; thickness, as much as 10,000 feet (3,000 m).

Oregon

Granite and diorite (Jurassic and Triassic) (Triassic and Jurassic)

Felsic to intermediate, granitoid intrusive rocks. Includes Jurassic muscovite granodiorite, hornblende gabbro, tonalite, and quartz diorite of southwest Oregon (Smith and others, 1982)

Granitic rocks (Cretaceous and Jurassic) (Late Jurassic and Early Cretaceous)

Mostly tonalite and quartz diorite but including lesser amounts of other granitoid rocks. Potassium-argon ages determined on hornblende indicates plutons range in age from 143 to 166 Ma (Hotz, 1971)

Hypabyssal intrusive rocks (Miocene and Miocene?) (Miocene)

Hypabyssal, medium-grained, hornblende diorite and quartz diorite in small stocks and large dikes; includes intrusions of medium- to fine-grained gabbro and plugs and small stocks of medium-grained, holocrystalline, olivine andesite. Also includes medium-grained, commonly porphyritic biotite quartz monzonite and leucocratic granodiorite. Many of these intrusive bodies are moderately to intensely propylitized, as are wallrocks they intrude; locally, along shears, the rocks also are sericitized. Potassium-argon ages on several of these shallow intrusions range from about 8 Ma to about 22 Ma (Wise, 1969; Bikerman, 1970; Sutter, 1978; Power and others, 1981a, b; Fiebelkorn and others, 1983)

Intrusive rocks (Cretaceous and Jurassic) (Jurassic to Cretaceous)

Hornblende and biotite quartz diorite (tonalite), trondhjemite, granodiorite, and small amounts of norite, in batholithic masses and large dikelike bodies. Includes Bald Mountain Tonalite and Anthony Lake Granodiorite of Taubeneck (1957), tonalite and trondhjemite of Wallowa batholith and Cornucopia stock (Taubeneck, 1964; Nolf, 1966), quartz diorite intrusion in the Snake River area (Morrison, 1963), quartz diorite and minor other intrusive rocks in the Caviness quadrangle (Wolff, 1965), quartz diorite northeast of John Day and southeast of Ironside Mountain (Thayer and Brown, 1964), quartz diorite in the Sparta and Durkee quadrangles (Prostka, 1962; 1967), and granodiorite and related rocks of the Pueblo Mountains (Roback and others, 1987). Rubidium-strontium and potassium-argon ages indicate an age range from about 94 to 160 Ma (Taubeneck, 1963; Thayer and Brown, 1964; Armstrong and others, 1976)

Mafic and intermediate intrusive rocks (Miocene) (Miocene)

Dikes, plugs, and sills of basalt, diabase, gabbro, and lesser andesite that fed many of the Miocene basalt and andesite flows in unit Tc. Some intrusions are rootless and are invasive into sedimentary sequences; includes related breccia and peperite. Includes Depoe Bay and Cape Foulweather dikes, sills, and plugs in the Coast Range (Snavely and others, 1976a, b; Wells and others, 1983)

Pennsylvania

Granitic gneiss and granite (Probably lower Paleozoic)

Granitic gneiss and granite - Includes Springfield Granodiorite (granitized Wissahickon) in Philadelphia area.

Rhode Island

Esmond Igneous Suite - mafic/intermediate rock (Late Proterozoic)

Esmond Igneous Suite - mafic/intermediate rock - Dark-gray, purple, or black, medium- to coarse-grained rock that may contain plagioclase, quartz, clinopyroxene, hornblende, olivine, and accessory biotite, epidote, sphene, zircon, apatite, and opaque minerals; secondary chlorite, sericite, and saussurite. Massive to variably foliated. Composition includes tonalite, quartz diorite, diorite, and gabbro. Includes rock mapped formerly as quartz diorite.

gabbro/diorite (Late Proterozoic? to Devonian?)

gabbro/diorite - Dark-gray to black, fine- to medium-grained, equigranular, faintly foliated rock, composed of plagioclase, clinopyroxene, hornblende, biotite, and accessory sphene, apatite, and opaque minerals. Includes quartz diorite, diorite, and gabbro.

Scituate Igneous Suite - diorite/gabbro (Devonian)

Scituate Igneous Suite - diorite/gabbro - Fine- to medium-grained, equigranular, massive to slightly foliated rock, composed of plagioclase, hornblende, clinopyroxene, and quartz, with accessory biotite, sphene, apatite, and opaque minerals; secondary chlorite, epidote, and saussurite. Varieties include quartz diorite, diorite, and gabbro.

Scituate Igneous Suite - monzonite/monzodiorite (Devonian)

Scituate Igneous Suite - monzonite/monzodiorite - Dark-gray to pink, fine- to medium-grained, equigranular rock, containing plagioclase, microcline, quartz, and accessory biotite, garnet, zircon, apatite, allanite, and opaque minerals; secondary muscovite and epidote. Mainly foliated. Varieties include quartz monzonite, monzonite, and monzodiorite. Includes some rock mapped formerly as Cowesett Granite.

South Carolina

Diorite (undetermined)

Diorite: includes unmetamorphosed, undeformed biotite-hornblende diorite

Diorite-gabbro- Clouds Creek pluton (Carboniferous)

Diorite-gabbro- Clouds Creek pluton

Metadiorite (Cambrian or Neoproterozoic)

Metadiorite

Metatonalite (Neoproterozoic)

Metatonalite: metamorphosed biotite tonalite and lesser amounts of hornblende tonalite, trondhjemite, and granodiorite

Tennessee

Bakersville Gabbro (Precambrian)

Bakersville Gabbro - Metagabbro, dark, porphyritic; contains diorite, basalt, anorthosite, and diabase; occurs as thin to massive dikes and lenticular masses.

Cranberry Granite (Precambrian)

Cranberry Granite - Complex of intertonguing rock types including migmatite, granitic gneisses, monzonite, quartz diorite, greenstone, mica and hornblende schists, abundant granitic pegmatite.

Intrusive igneous rocks (Paleozoic (?))

Intrusive Igneous Rocks - Metadiorite and metagabbro in Polk County, intrude Great Smoky Group.

Intrusive igneous rocks (Precambrian)

Intrusive Igneous Rocks - Mica peridotite plugs (two in Union County), intrude Sneedville Limestone; metadiorite and metagabbro sills and dikes in Sevier County, intrude Great Smoky Group.

Mount Rogers Group including Bakersville Gabbro, Beech Granite, Cranberry Granite, and Roan Gneiss (Precambrian)

Mount Rogers Group - Metavolcanics, typically purplish and reddish; massive lavas and tuffs, altered rhyolites and quartz latites; strongly foliated; interbedded arkose, shale, and conglomerate. Thickness 1,000 to 3,000 feet; Includes Bakersville Gabbro - Metagabbro, dark, porphyritic; contains diorite, basalt, anorthosite, and diabase; occurs as thin to massive dikes and lenticular masses; Beech Granite - Granite, porphyritic, light-gray to reddish; coarse potash feldspar crystals and clustered interstitial mafics (chloritized biotite and hornblende) give spotted appearance; includes Max Patch Granite; Cranberry Granite - Complex of intertonguing rock types including migmatite, granitic gneisses, monzonite, quartz diorite, greenstone, mica and hornblende schists, abundant granitic pegmatite; and Roan Gneiss - Layered hornblende and garnet gneiss and granitic migmatite with zones of mica schist and amphibolite, foliation commonly contorted; contains numerous granitic and gabbroic dikes.

Texas

Mafic igneous rocks (preCambrian-Proterozoic)

Mafic igneous rocks

Utah

Jurassic intrusive rocks in western Utah (Jurassic)

Tertiary intrusive rocks in central Utah (Late Eocene to Oligocene)

Tertiary intrusive rocks in northwestern Utah (Oligocene)

Tertiary intrusive rocks in Salt Lake City-Coalville-Randolph region (Late Eocene to Oligocene)

Tertiary intrusive rocks in southeastern Utah (Oligocene)

Tertiary intrusive rocks in western Utah (Late Eocene to Early Miocene)

Virginia

Altered Diorite and Gabbro (Proterozoic)

Altered diorite and gabbro

Diorite and Quartz Diorite (Proterozoic)

Diorite and quartz diorite.

Falmouth Intrusive Suite (Mississippian - Pennsylvanian)

Falmouth Intrusive Suite - Granite, quartz monzonite, granodiorite, and tonalite

Green Springs Pluton - Diorite and hornblendite. (Proterozoic Y-Pennsylvanian)

Green Springs Pluton - Diorite and hornblendite.

Melrose Granite (Cambrian)

Melrose Granite - Granite

Metatonalite (Proterozoic)

Metatonalite

Rich Acres Formation (Cambrian)

Rich Acres Formation - Norite, metagabbro, and diorite.

Vermont

Hornblende-biotite diorite; gabbro (Permian-Triassic)

Hornblende-biotite diorite; gabbro.

Undifferentiated Gneiss (Precambrian)

Undifferentiated Gneiss - Undifferentiated gneissic biotite granite, quartz monzonite, and granodiorite.

Washington

Basic intrusive rocks, undivided (Jurassic in central Cascades; Oligocene to Eocene in northern Cascades)

Predominantly gabbro; includes some serpentine. Age undetermined.

Mesozoic alkali intrusive rocks (Jurassic-Cretaceous)

Syenite in Nighthawk and Buckhorn Mountain areas of Okanogan County; malignite on Kruger Mountain near Nighthawk.

Mesozoic granitic rocks, undivided (Mostly Cretaceous-Jurassic)

Granite, quartz monzonite, quartz diorite, granodiorite, and trondhjemite. Includes diorite in southeastern Washington; diorite and gabbro near Concunully in Okanogan County; gneiss, schist, and migmatites in areas of Chelan, Colville, and Okanogan batholiths. Includes high-grade metamorphic rocks of Precambrian age in Spokane area.

Precambrian intrusive rocks (Middle Proterozoic(?))

Dark-gray diorite sills from 3 to 1200 feet thick. Confined to Bead Lake district, southeastern Pend Oreille County. Tentatively assigned to the Precambrian.

Pre-Carboniferous crystalline complex (Devonian)

Metahornblendite, amphibolite, gneiss, metadiorite, meta-quartz diorite, and trondhjemite. As klippes along western slope of northern Cascade Mountains.

Pre-Carboniferous intrusive rocks (Paleozoic)

Meta-quartz diorite, hypersthene diorite, and gneissose and directionless quartz diorite of eastern Skagit County. Quartz diorite and diorite in the San Juan Islands. Includes amphibolite and gneiss locally.

Pre-Middle Jurassic volcanic rocks, undivided (Early Cretaceous-Late Jurassic)

Predominantly greenstone and spilitic volcanic rocks; includes some slate, argillite, and graywacke.

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.

Pre-Tertiary ultrabasic intrusive rocks (Late-Jurassic)

Peridotite and pyroxenite; generally altered partly or completely to serpentine. Includes serpentinite and saxonite on Sumas Mountain, Whatcom County.

Pre-Tertiary volcanic rocks, undivided (Probably mostly Jurassic)

Andesite and basalt flows, and greenstone; includes minor interbedded limestone, arkose, quartzite, and chert beds.

Pre-Upper Jurassic metamorphic rocks of the medium and high-grade zone (Early Jurassic-Triassic)

Schist, amphibolite, and minor lime-silicate rocks, marble, quartzite, and metaconglomerate.

Tertiary-Cretaceous basic intrusive rocks (Cretaceous-Jurassic)

Diorite and gabbro in western Snohomish County.

Tertiary-Cretaceous granitic intrusive rocks (Early Tertiary-Late Cretaceous)

Granite, granodiorite, trondhjemite, and quartz diorite. Late Cretaceous and/or early Tertiary.

Tertiary dikes, sills, and small intrusive bodies (Middle to Late Tertiary)

Dikes are commonly diabase; plugs and sills are generally andesite porphyry and dacite.

Tertiary granitic rocks (Probably mostly Eocene; ranges from Miocene to Paleocene)

Granite, quartz monzonite, quartz diorite, granodiorite, and trondhjemite. Includes dacite porphyry and granite breccia near Bumping Lake, Yakima County.

Upper Jurassic-Lower Cretaceous sedimentary and volcanic rocks (Late Jurassic-Early Cretaceous)

Predominantly sedimentary rocks. Graywacke, argillite, and siltstone with some slate and phyllite; includes graywacke breccia and ribbon chert with minor local limestone lenses and basalt flows.

Wisconsin

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