Geologic units containing volcanic rock (aphanitic)

Mineral Resources On-Line Spatial Data

Earth material

Volcanic rock

A generally finely crystalline or glassy igneous rock resulting from volcanic action at or near the Earth's surface, either ejected explosively or extruded as a lava. The term includes near-surface intrusions that form a part of the volcanic structure.

This category is also used for volcanic rock (aphanitic).

Arkansas

Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late): Woodbine Formation

California

Miocene nonmarine rocks (Oligocene to Pleistocene): Sandstone, shale, conglomerate, and fanglomerate; in part Pliocene and Oligocene.
Paleozoic marine rocks, undivided, unit 9 (Western Klamath Mountains) (Devonian to Jurassic): Undivided Paleozoic metasedimentary rocks. Includes slate, sandstone, shale, chert, conglomerate, limestone, dolomite, marble, phyllite, schist, hornfels, and quartzite
Tertiary nonmarine rocks, undivided (Paleocene to Pliocene): Undivided Tertiary sandstone, shale, conglomerate, breccia, and ancient lake deposits.
Triassic marine rocks, unit 6 (Southern Sierra Nevada) (Late Triassic to Early Jurassic): Shale, conglomerate, limestone and dolomite, sandstone, slate, hornfels, quartzite; minor pyroclastic rocks

Massachusetts

Newbury Volcanic Complex (Lower Devonian and Upper Silurian): Newbury Volcanic Complex - Undivided sedimentary and volcanic rocks.

Maine

Silurian Quoddy Formation undifferentiated volcanic rock member (Silurian): Silurian Quoddy Formation undifferentiated volcanic rock member

Montana

Cretaceous volcanic rocks (Phanerozoic | Mesozoic Cenozoic | Cretaceous-Late Tertiary): Cretaceous volcanic rocks: flows and pyroclastic rocks, mainly of intermediate composition with subordinate amounts of interbedded sedimentary rocks. Some of the rocks have been regarded as belonging to the Livingston formation, but this usage is not adopted here. Where data are inadequate for separation, some Tertiary volcanic rocks may be mapped with the Cretaceous volcanic rocks.
Livingston formation (Phanerozoic | Cenozoic | Tertiary Cretaceous): Livingston formation: water-laid volcanic material, mainly andesitic in composition; includes agglomerate, conglomerate, sandstone, and shale. The name here is used only for the rocks orginally named, mainly near and north of Livingston. These rocks include age equivalents of various Cretaceous and Paleocene units.
Tertiary volcanic rocks (Phanerozoic | Cenozoic | Tertiary): Tertiary volcanic rocks: Flows and associated pyroclastic deposits, with subordinate amounts of intercalated sedimentary beds and lignite. The volcanic material is mostly latite, quartz latite, and andesite but includes some rhyolite and basalt. The distinction between Tertiary and pre-Tertiary volcanic rocks was not made in some of the reports used in the complilation. Hence in the less well-known areas some pre-Tertiary volcanic rocks may be included.
Two Medicine formation (Phanerozoic | Mesozoic | Cretaceous-Late): Two Medicine formation: greenish-gray clay with local nodular limestone and crossbedded sandstone; locally some coal in lower part. Rocks equivalent to Judith River formation, Claggett formation, and upper part of Eagle sandstone are included in this unit.

New Mexico

Cretaceous rocks, undivided (Phanerozoic | Mesozoic | Cretaceous): Cretaceous rocks, undivided
sedimentary and vocaniclastic sedimentary rocks (Phanerozoic | Cenozoic | Tertiary): Mostly Oligocene and upper Eocene sedimentary and volcaniclastic sedimentary rocks with local andesitic to intermediate volcanics; includes Espinaso, Spears, Bell Top, and Palm Park Formations
silicic pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary): Lower Oligocene silicic pyroclastic rocks (ash-flow tuffs); includes Hell's Mesa, Kneeling Nun, lower part of Bell Top Formation, Caballo Blanco, Datil Well, Leyba Well, Rock House Canyon, Blue Canyon, Sugarlump and Tadpole Ridge Tuffs, the tuffs of the Organ cauldron, Treasure Mountain Tuff (now known as Chiquito Peak Tuff), Bluff Creek Tuff, Oak Creek Tuff, tuff of Steins Mountain, tuff of Black Bill Canyon, tuff of Farr Ranch, Woodhaul Canyon, Gillespie and Box Canyon Tuffs, Cooney Tuff, and other volcanic and interbedded fluvial and pumiceous units; (31-36.5 Ma)
silicic volcanic rocks (Phanerozoic | Cenozoic | Quaternary): Silicic volcanic rocks
undivided, Upper Cretaceous (Phanerozoic | Mesozoic | Cretaceous): Upper Cretaceous, undivided. Includes Virden Formation in northern Hidalgo County, Ringbone Formation in Hidalgo and Luna and Grant Counties, and locally Beartooth and Sarten, Mancos in Silver City area; Cenomanian - Maastrichtian for most part, although Beartooth is pre-Cenomanian
upper Tertiary sedimentary units (Phanerozoic | Cenozoic | Tertiary): Upper Tertiary sedimentary units; includes Bidahochi Formation, the Picuris Formation, and Las Feveras Formation, and locally fanglomerates; Pliocene to upper Miocene
volcanic and some volcaniclastic rocks (Phanerozoic | Cenozoic | Tertiary): Volcanic and some volcaniclastic rocks, undifferentiated; lower Miocene and Upper Oligocene (younger than 29 Ma)
volcanic rocks, lower Oligocene and Eocene (Phanerozoic | Cenozoic | Tertiary): Lower Oligocene and Eocene volcanic rocks, undifferentiated; dominantly intermediate composition, with interbedded volcaniclastic rocks; (31-44 Ma)
volcanic rocks, middle Tertiary (Phanerozoic | Cenozoic | Tertiary): Middle Tertiary volcanic rocks, undifferentiated
volcanic rocks, Neogene (Phanerozoic | Cenozoic | Tertiary): Neogene volcanic rocks; primarily in Jemez Mountains

Nevada

Dunlap Formation (Early Jurassic to Middle Jurassic): DUNLAP FORMATION (Lower and Middle Jurassic)-Conglomerate, sandstone, greenstone, felsite, and tuff. Locally contemporaneous with folding and thrusting. Mineral County and adjacent parts of Esmeralda and Nye Counties
Shale, mudstone, siltstone, sandstone, and carbonate rock; sparse volcanic rock (Late Triassic to Early Jurassic): SHALE, MUDSTONE, SILTSTONE, SANDSTONE, AND CARBONATE ROCK; SPARSE VOLCANIC ROCK (Upper Triassic and Lower Jurassic)-Includes Auld Lang Syne Group, Nightingale sequence of Bonham (1969), and Gabbs and Sunrise Formations
Volcanogenic sedimentary rocks, tuff, andesite and felsitic flows, and carbonate rocks (Permian to Jurassic (?)): VOLCANOGENIC SEDIMENTARY ROCKS, TUFF, ANDESITIC AND FELSITIC FLOWS, AND CARBONATE ROCKS-Age uncertain. Mineral, Esmeralda, and Northwest Nye Counties

Rhode Island

Conanicut Group - East Passage Formation (Cambro-Ordovician): Conanicut Group - East Passage Formation - Red, orange-brown, and gray-green phyllite and thinly-bedded, nongraded sandstone and siltstone; rare limestone, and sparse volcanic rock including welded-tuff.
Conanicut Group - undifferentiated rock (Cambro-Ordovician): Conanicut Group - undifferentiated rock - Consists of associations of the above rock types.

Texas

Allamore Formation (preCambrian-Proterozoic [Grenville]): Allamore Formation

Utah

Tertiary (5) sedimentary rocks in Uinta Mountains-Uinta Basin region (Miocene)
Tertiary volcanic rocks, undivided (Tertiary)

Virginia

Chilhowee Group (Cambrian): Chilhowee Group - Appalachian Plateaus and Valley and Ridge: Quartzite, conglomerate, feldspathic sandstone, phyllite, and minor ferruginous sandstone and volcanic rocks. Blue Ridge Anticlinorium: Conglomerate, quartzite, metasiltstone, and phyllite.

Washington

Carboniferous-Permian sedimentary and volcanic rocks (Devonian to Permian, minor Mesozoic): Predominantly sedimentary rocks. Graywacke, argillite, and slate; includes minor marble, siltstone, arkose, conglomerate, ribbon cherts, and volcanic rocks. Some Devonian rocks may be included in northwestern Washington.
Upper Jurassic-Lower Cretaceous volcanic rocks (Jurassic-Cretaceous on San Juan Islands; possibly Eocene in King County): Predominantly volcanic rocks, mostly metamorphosed to greenstone and greenschist; includes some sedimentary rocks

Wyoming

Intrusive and extrusive igneous rocks (Phanerozoic | Cenozoic | Tertiary | Eocene): INTRUSIVE AND EXTRUSIVE IGNEOUS ROCKS (CHIEFLY EOCENE; AGE OF INTRUSIVES ABOUT 53 TO 55 Ma)--Incorporates masses of Mississippian through Cambrian formations. Confined to Black Hills.