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Mineral Resources > Online Spatial Data > Geology > by state > New Mexico Geology

Geologic units in Rio Arriba county, New Mexico

[Additional scientific data in this geographic area]

metasedimentary rocks (Proterozoic | Paleoproterozoic) at surface, covers 1 % of this area

Lower Proterozoic metasedimentary rocks (1650-1700 Ma). Essentially equivalent to Hondo Group; locally includes high-grade quartzite-pelitic schist of unknown age

Lithology: metasedimentary rock

plutonic rocks, Lower Proterozoic (Proterozoic | Paleoproterozoic) at surface, covers 1 % of this area

Lower Proterozoic plutonic rocks (older than 1600 Ma)

Lithology: plutonic rock (phaneritic)

Cutler Formation (Phanerozoic | Paleozoic | Permian) at surface, covers 2 % of this area

Cutler Formation; used in northern areas and Chama embayment only

Lithology: sandstone; medium-grained mixed clastic; limestone

Abo Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Abo Formation; red beds, arkosic at base, finer and more mature above; Wolfcampian; may include limestone beds of Pennsylvanian age (Virgilian) in Zuni Mountains. In Robledo Mountains the Abo may be considered a member of the Hueco Formation

Lithology: sandstone; shale; conglomerate; limestone

Mesaverde Group (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 3 % of this area

Mesaverde Group includes the Gallup Sandstone, Crevasse Canyon Formation, Point Lookout Sandstone, Menefee Formation, and Cliff House Sandstone

Lithology: sandstone; fine-grained mixed clastic; conglomerate; coal

volcanic rocks, Neogene (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Neogene volcanic rocks; primarily in Jemez Mountains

Lithology: volcanic rock (aphanitic)

mafic metamorphic rocks, lower Proterozoic (Proterozoic | Paleoproterozoic) at surface, covers 0.3 % of this area

Lower Proterozoic metamorphic rocks, dominantly mafic (1720-1760 Ma)

Lithology: mafic metavolcanic rock

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 10 % of this area

Mancos Shale; divided into Upper and Lower parts by Gallup Sandstone

Lithology: shale; fine-grained mixed clastic

Chinle Group (Phanerozoic | Mesozoic | Triassic) at surface, covers 3 % of this area

Chinle Group; Upper Triassic; includes Moenkopi Formation (Middle Triassic) at base in many areas; in eastern part of state the following five formations are mapped:

Lithology: medium-grained mixed clastic; fine-grained mixed clastic; limestone; chert; evaporite

silicic pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % of this area

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)

Lithology: pyroclastic; tuff; felsic volcanic rock; volcanic rock (aphanitic); mixed clastic/volcanic

eolian deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Eolian deposits

Lithology: eolian

rhyolitic pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Upper Oligocene rhyolitic pyroclastic rocks (ash-flow tuffs); includes Davis Canyon Tuff, South Crosby Peak Formation, La Jencia, Vick's Peak, Lemitar, South Canyon, Bloodgood Canyon, Shelley Peak Tuffs, tuff of Horseshoe Canyon, Park Tuff, Rhyolite Canyon Tuff, Apache Springs Tuff, Diamond Creek, Jordan Canyon, Garcia Camp Tuffs, the Turkey Springs Tuff, the tuff of Little Mineral Creek, the Amalia Tuff, and others. Some contain volcaniclastic and reworked volcaniclastic rocks, and eolian sandstone; (24-29 Ma)

Lithology: tuff; pyroclastic; rhyolite; andesite; mixed clastic/volcanic; eolian

plutonic rocks, middle Proterozoic (Proterozoic | Mesoproterozoic) at surface, covers < 0.1 % of this area

Middle Proterozoic plutonic rocks (younger than 1600 Ma)

Lithology: plutonic rock (phaneritic)

alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 2 % of this area

Alluvium; upper and middle Quaternary

Lithology: alluvium

Morrison Formation (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.6 % of this area

Morrison Formation; Upper Jurassic nonmarine rocks present only in northern one-third of state

Lithology: fine-grained mixed clastic; limestone

Bandelier Tuff (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.8 % of this area

Bandelier Tuff; Jemez Mountains area only

Lithology: rhyolite; tuff; pumice

basalt and andesite flows and vent deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.3 % of this area

Basalt and andesite flows and locally vent deposits

Lithology: andesite; basalt

basalt and andesite flows, Neogene (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Basalt and andesite flows; Neogene. Includes flows interbedded with Santa Fe and Gila Groups

Lithology: basalt; andesite

Kirtland and Fruitland Formations (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.2 % of this area

Kirtland and Fruitland Formations; coal-bearing, coal primarily in the Fruitland; Campanian to Maastrichtian

Lithology: sandstone; mudstone; coal

Lower and Middle Santa Fe Group (Phanerozoic | Cenozoic | Tertiary) at surface, covers 6 % of this area

Lower and Middle Santa Fe Group. Includes Hayner Ranch, Rincon Valley, Popotosa, Cochiti, Tesuque, Chamita, Abiquiu, and other Formations; Miocene and uppermost Oligocene

Lithology: coarse-grained mixed clastic; unconsolidated deposit; tuff; chert

Modern alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Includes Piney Creek Alluvium and younger deposits

Lithology: alluvium

Pictured Cliffs Sandstone and Lewis Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

Lithology: sandstone; shale

middle and upper Jurassic rocks, unidivided (Phanerozoic | Mesozoic | Jurassic) at surface, covers 1 % of this area

Jurassic rocks, Middle and Upper, undivided

Lithology: clastic; sedimentary rock

Madera Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 0.5 % of this area

Madera Formation (Limestone, or Group); in Manzano Mountains includes Los Moyos Limestone and Wild Cow Formation; in Lucero Mesa includes Gray Mesa, Atrasdo, and Red Tanks Members; in Sacramento Mountains includes Beeman and Holder Formations; may include strata lumped as Magdalena Group in a few areas

Lithology: limestone; fine-grained mixed clastic

Los Pinos Formation of Lower Santa Fe Group (Phanerozoic | Cenozoic | Tertiary) at surface, covers 7 % of this area

Los Pinos Formation of Lower Santa Fe Group (Miocene and upper Oligocene); includes Carson Conglomerate (Dane and Bachman, 1965) in Tusas Mountains-San Luis Basin area

Lithology: unconsolidated deposit; sand; gravel; basalt

Santa Fe Group (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers < 0.1 % of this area

Santa Fe Group, undivided. Basin fill of Rio Grande rift region; middle Pleistocene to uppermost Oligocene

Lithology: clastic; carbonate; lava flow; andesite

volcanic rocks, middle Tertiary (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Middle Tertiary volcanic rocks, undifferentiated

Lithology: volcanic rock (aphanitic)

Mesaverde Fm, undivided (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

In northwest and west-central: Major coal beds in lower part; Rollins Sandstone Member at base in Delta, Gunnison, and Pitkin Counties. In southwest: sandstone and shale.

Lithology: sandstone; shale; coal

metamorphic rocks (Proterozoic | Paleoproterozoic) at surface, covers 1.0 % of this area

Lower Proterozoic metamorphic rocks, dominantly felsic volcanic, volcaniclastic and plutonic rocks (1650-1700+ Ma); includes Vadito Group; locally includes high-grade felsic gneisses of unknown age

Lithology: felsic metavolcanic rock; plutonic rock (phaneritic); felsic gneiss

sedimentary units, Palogene (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Paleogene sedimentary units; includes Baca, Galisteo, El Rito, Blanco Basin, Love Ranch, Lobo, Sanders Canyon, Skunk Ranch, Timberlake, and Cub Mountain Formations

Lithology: medium-grained mixed clastic; tuff; limestone; sand; clay or mud

Ojo Alamo Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.1 % of this area

Ojo Alamo Formation; Paleocene, San Juan Basin

Lithology: sandstone; shale; conglomerate

San Rafael Group (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.6 % of this area

San Rafael Group; consists of Entrada Sandstone, Todilto and Summerville Formations, Bluff Sandstone, and locally Zuni Sandstone (or only Acoma Tongue of Zuni)

Lithology: medium-grained mixed clastic; fine-grained mixed clastic; evaporite; limestone

Los Pinos Fm (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Volcaniclastic conglomerate interbedded with basalt flows of Hinsdale Fm (Tbb) on east flank of San Juan Mountains. Grades laterally into Santa Fe Fm of San Luis Valley

Lithology: mixed clastic/volcanic; basalt

landslide deposits and colluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 2 % of this area

Landslide deposits and colluvium

Lithology: landslide; colluvium

piedmont alluvial deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 2 % of this area

Piedmont alluvial deposits: upper and middle Quaternary; includes deposits of higher gradient tributaries bordering major stream valleys, alluvial veneers of the piedmont slope, and alluvial fans

Lithology: alluvium

silicic to intermediate intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Miocene to Oligocene silicic to intermediate intrusive rocks; dikes, stocks, plugs, and diatremes

Lithology: plutonic rock (phaneritic)

intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Tertiary intrusive rocks; undifferentiated

Lithology: plutonic rock (phaneritic)

Nacimiento Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.6 % of this area

Nacimiento Formation; Paleocene, San Juan Basin

Lithology: sandstone; shale; conglomerate

Pictured Cliffs Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

Pictured Cliffs Sandstone; prominent cliff-forming marine sandstone

Lithology: sandstone; mudstone

silicic to intermediate volcanic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Silicic to intermediate volcanic rocks; mainly quartz latite and rhyolite Neogene; may locally include flows interbedded with Santa Fe Group

Lithology: felsic volcanic rock; intermediate volcanic rock

Pre-ash-flow andesitic lavas, breccias, tuffs, and conglomerates (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Includes several named units

Lithology: andesite; tuff; volcanic breccia (agglomerate)

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

In northwest and west-central: Intertongues complexly with units of overlying Mesaverde Group or Fm; lower part consists of a calcareous Niobrara equivalent and Frontier Sandstone and Mowry Shale Members; in areas where the Frontie

Lithology: shale; sandstone

Animas Formation (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 2 % of this area

Animas Formation; in northeast San Juan Basin

Lithology: clay or mud; tuff; clastic

Hinsdale Basalt (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % of this area

Hinsdale Basalt; northern Taos and eastern Rio Arriba Counties; basalt flows interbedded with Los Pinos Formation

Lithology: basalt; rhyolite; alluvium

Lewis Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 3 % of this area

Lewis Shale; marine shale and mudstone

Lithology: shale; fine-grained mixed clastic; limestone

Sandia Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers < 0.1 % of this area

Sandia Formation; predominately clastic unit (commonly arkosic) with minor black shales, and limestone in lower part; locally includes Osha Canyon Formation in Nacimiento Mountains

Lithology: sandstone; shale; limestone; conglomerate

Dakota Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 4 % of this area

Dakota Sandstone; includes Oak Canyon, Cubero, and Paguate Tongues plus Clay Mesa Tongue of Mancos Shale; Cenomanian

Lithology: medium-grained mixed clastic

Permain and Pennsylvanian rocks, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 0.3 % of this area

Permian and Pennsylvanian rocks, undivided; includes Horquilla Limestone, Earp Formation, Epitaph and Scherrer Formations, and Concha Limestone

Lithology: medium-grained mixed clastic; carbonate

lower Proterozoic rocks, undivided (Proterozoic | Paleoproterozoic) at surface, covers < 0.1 % of this area

Lower Proterozoic rocks, undivided

Lithology: indeterminate

San Jose Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 31 % of this area

San Jose Formation; Eocene, San Juan Basin

Lithology: medium-grained mixed clastic

Upper Santa Fe Group (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers 2 % of this area

Upper Santa Fe Group. Includes Camp Rice, Fort Hancock, Palomas, Sierra Ladrones, Ancha, Puye, and Alamosa Formations; middle Pleistocene to uppermost Miocene

Lithology: clastic; unconsolidated deposit; mixed clastic/volcanic

Ash-flow tuff of main volcanic sequence (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Includes many named units

Lithology: ash-flow tuff

Basalt flows and associated tuff, breccia, and conglomerate of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Includes basalts of Hinsdale Fm in San Juan Mountains - Servilleta Fm in San Luis Valley and many other occurrences

Lithology: basalt; tuff; volcanic breccia (agglomerate); conglomerate

silicic volcanic rocks (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Silicic volcanic rocks

Lithology: volcanic rock (aphanitic)

volcanic rocks, lower Oligocene and Eocene (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Lower Oligocene and Eocene volcanic rocks, undifferentiated; dominantly intermediate composition, with interbedded volcaniclastic rocks; (31-44 Ma)

Lithology: volcanic rock (aphanitic); intermediate volcanic rock; mixed clastic/volcanic

plutonic rocks, middle and lower Proterozoic (Proterozoic | Paleoproterozoic Mesoproterozoic) at surface, covers 0.4 % of this area

Middle and Lower Proterozoic plutonic rocks, undivided

Lithology: plutonic rock (phaneritic)