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Geologic units containing aplite

Alabama

Zana Granite (Precambrian to Paleozoic)

Zana Granite - quartz monzonite to granite with strong gneissic texture, cut by small pegmatites and aplite dikes, generally elongate; semiconcordant to foliation of country rock.

Arizona

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)

Early Tertiary to Late Cretaceous muscovite-bearing granitic rocks (Late Cretaceous to Early Tertiary)

Light-colored peraluminous muscovite granite with or without garnet; commonly forms sills and is associated with abundant pegmatite dikes and sills. This unit includes granites in the Harcuvar and Harquahala Mountains of western Arizona and in the Santa Catalina, Rincon, Tortolita, Picacho, and Coyote Mountains of south-central Arizona. These granites typically represent the youngest phase of voluminous magmatism during the Laramide orogeny in Arizona. This unit also includes several muscovite-bearing granites in southern Arizona that are associated with calc-alkaline granites of unit TKg, and a batholith in the Cabeza Prieta area of southwestern Arizona. (50-80 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 Proterozoic diabase (Middle Proterozoic)

Dark gray to black sills (intrusions mostly parallel to bedding) in strata of the Apache Group and irregular to sheet-like intrusions in other rocks. Present in east-central and southeastern Arizona. Some sills are more than 100 m thick. Exposures are extensive north of Globe. (1050-1150 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)

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 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 5 (Klamath Mountains) (Jurassic to early Cretaceous)

Mesozoic granite, quartz monzonite, granodiorite, and quartz diorite

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.

Peraluminous monzogranite, granodiorite, pegmatite, aplite, and migmatite; mostly Cretaceous intrusions of the Kaniksu batholithic assemblage, but with minor Eocene intrusions, undivided; northern Idaho (Cretaceous to Eocene)

Cretaceous plutons; felsic; as granite or quartz monzonite; probably includes unmapped older and younger crystalline bodies.

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.

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.

North Carolina

Injected Gneiss (Cambrian/Late Proterozoic)

Injected Gneiss - biotite gneiss and schist intruded by numerous sills and dikes of granite, pegmatite, and aplite; minor hornblende gneiss.

Rhode Island

Narragansett Pier Plutonic Suite - granite (Permian)

Narragansett Pier Plutonic Suite - granite - Dark-pink to pale-gray, medium-grained equigranular granite, with lesser granodiorite and quartz monzonite. Composed of microcline, oligoclase, quartz, and accessory biotite, magnetite, ilmenite, apatite, sphene, zircon, monazite, apatite, and allanite; muscovite and garnet locally present; secondary chlorite and calcite. Mainly massive, but locally exhibits faint flow foliation. Cut locally by abundant pegmatite, aplite, and composite aplite-pegmatite of mineralogy similar to the host granite. Unit is a 5 km by 40 km batholith that underlies the southern coast of RI. Intrusion during the latter part of Alleghanian deformation of the Narragansett Basin is indicated by its Permian age, rapid cooling, and field relations. The age of the Narragansett Pier is well constrained by several factors. Brown and others (1978) report a Pennsylvanian fossil contained in an inclusion in the pluton. Radiometric ages of 276 Ma by Kocis and others (1978), 272+/-4 Ma by Hermes and others (1981), and 273+/-2 Ma by Zartman and Hermes (1987) are consistently Early Permian. Structural studies by Mosher (1983) and Reck and Mosther (1988) indicate that intrusion began during the third period of deformation in the Narragansett Basin. Argon release patterns (Dallmeyer, 1982) indicate that the granite and intruded sediments had cooled below argon retention temperatures of hornblende by the Late Permian and of biotite by the Early Triassic. Intruded by the Westerly Granite, which has been radiometrically dated at 276+/-7 Ma. The two granites are probably genetically related based on similarities in age, mineralogy, and geochemistry (Hozik, 1992).

Narragansett Pier Plutonic Suite - leucocratic granite (Permian)

Narragansett Pier Plutonic Suite - leucocratic granite - White to gray leucocratic granite composed of microcline, oligoclase, and quartz. Up to 10% accessory muscovite and garnet, with lesser apatite, zircon, and monazite. Biotite and opaque minerals notably sparse or absent. Mainly massive, but locally exhibits flow foliation caused by alternating layers of pegmatite, aplite, and medium-grained equigranular granite; pegmatitic and aplitic material of mineralogy similar to the host granite. The granite contains widespread xenolithic inclusions and screens of metasedimentary rock, some of which are PAnbr; bedding and fabric in the screens generally is oriented parallel to that in the host metasedimentary country rock. Unit is a 5 km by 40 km batholith that underlies the southern coast of RI. Intrusion during the latter part of Alleghanian deformation of the Narragansett Basin is indicated by its Permian age, rapid cooling, and field relations. The age of the Narragansett Pier is well constrained by several factors. Brown and others (1978) report a Pennsylvanian fossil contained in an inclusion in the pluton. Radiometric ages of 276 Ma by Kocis and others (1978), 272+/-4 Ma by Hermes and others (1981), and 273+/-2 Ma by Zartman and Hermes (1987) are consistently Early Permian. Structural studies by Mosher (1983) and Reck and Mosther (1988) indicate that intrusion began during the third period of deformation in the Narragansett Basin. Argon release patterns (Dallmeyer, 1982) indicate that the granite and intruded sediments had cooled below argon retention temperatures of hornblende by the Late Permian and of biotite by the Early Triassic. Intruded by the Westerly Granite, which has been radiometrically dated at 276+/-7 Ma. The two granites are probably genetically related based on similarities in age, mineralogy, and geochemistry (Hozik, 1992).

Texas

Younger granitic intrusion (preCambrian-Proterozoic)

Younger granitic intrusion

Utah

Jurassic intrusive rocks in western Utah (Jurassic)

Wisconsin

Wausau Pluton; Aplite (Middle Proterozoic)

Wausau Pluton; Aplite- Pale-orange to pink, fine-grained porphyritic aplite