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

Geologic units in Grant county, New Mexico

Permain and Pennsylvanian rocks, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 0.8 % 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

undivided, Upper Cretaceous (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.3 % of this area

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

Lithology: medium-grained mixed clastic; volcanic rock (aphanitic); limestone

Gila Group (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers 31 % of this area

Gila Group. Includes Mimbres Formation and several informal units in southwestern basins; Middle Pleistocene to uppermost Oligocene

Lithology: conglomerate; sandstone; basalt

Mancos Formation and Beartooth Quartzite (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 1 % of this area

Mancos Formation and Beartooth Quartzite (and Sarten Sandstone); Mancos includes what was formerly referred to as Colorado Shale which in turn may include equivalents of Tres Hermanos Formation

Lithology: shale; sandstone; medium-grained mixed clastic

older piedmont alluvial deposits and shallow basin fill (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers 0.3 % of this area

Older piedmont alluvial deposits and shallow basin fill; includes Quemado Formation and in northeast, high level pediment gravels

Lithology: alluvium; unconsolidated deposit

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

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

Lithology: clastic; mixed clastic/volcanic; volcanic rock (aphanitic); unconsolidated deposit

Paleozoic rocks, undivided (Phanerozoic | Paleozoic) at surface, covers 0.2 % of this area

Paleozoic rocks, undivided

Lithology: sedimentary rock

Silurian through Cambrian rocks, undivided (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian) at surface, covers 0.6 % of this area

Silurian through Cambrian rocks, undivided

Lithology: sedimentary rock

silicic flows and massess and associated pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 4 % of this area

Upper Oligocene silicic (or felsic) flows and masses and associated pyroclastic rocks; includes Taylor Creek, Fanney, and Rocky Canyon Rhyolites

Lithology: felsic volcanic rock; pyroclastic; rhyolite

volcanic rocks, lower Oligocene and Eocene (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.3 % 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

intrusive rocks, Paleogene and Upper Cretatceous (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 0.9 % of this area

Paleogene and Upper Cretaceous intrusive rocks; includes Hanover, Fierro, Tyrone, and Lordsburg granodiorite-quartz monzonite porphyries

Lithology: granodiorite; granitoid

piedmont alluvial deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 13 % 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)

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

Upper and Middle Tertiary mafic intrusive rocks

Lithology: plutonic rock (phaneritic)

intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.5 % of this area

Tertiary intrusive rocks; undifferentiated

Lithology: plutonic rock (phaneritic)

silicic to intermediate volcanic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % 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

basaltic andesites (Phanerozoic | Cenozoic | Tertiary) at surface, covers 9 % of this area

Lower Miocene and uppermost Oligocene basaltic andesites (22-26 Ma). Includes Bearwallow Mountain Andesite and basaltic andesite of Mangas Mountain

Lithology: andesite; basalt; intermediate volcanic rock; mafic volcanic rock

andesitic volcanics (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 1 % of this area

Andesitic volcanics

Lithology: andesite; intermediate volcanic rock

plutonic rocks, middle Proterozoic (Proterozoic | Mesoproterozoic) at surface, covers 5 % of this area

Middle Proterozoic plutonic rocks (younger than 1600 Ma)

Lithology: plutonic rock (phaneritic)

alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 3 % of this area

Alluvium; upper and middle Quaternary

Lithology: alluvium

andesites and basaltic andesites (Phanerozoic | Cenozoic | Tertiary) at surface, covers 7 % of this area

Upper Oligocene andesites and basaltic andesites (26-29 Ma); includes La Jara Peak Basaltic Andesite, Uvas Basalt, the basaltic andesite of Poverty Creek, and Squirrel Springs Andesite, the Razorback, Bear Springs Canyon, Salt Creek, Gila Flat, and Middle Mountain Formations, and the Alum Mountain Group; locally includes more silicic flows

Lithology: andesite; basalt; intermediate volcanic rock; mafic volcanic rock; felsic volcanic rock; rhyolite

quartz monzonites, intermediate intrusives, and other intermediate felsic dikes and plugs (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.5 % of this area

Quartz monzonites (Eocene) in the Silver City and Los Pinos Range, intermediate intrusives of the Cooke's Range (Oligocene), and other intermediate to felsic dikes and plugs of Oligocene and Eocene age

Lithology: quartz monzonite; granitoid

basalt and andesite flows, Neogene (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.3 % of this area

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

Lithology: basalt; andesite

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

andesite and basaltic andesite flows and associated volcaniclastic units (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Lower Tertiary, (Lower Oligocene and Eocene) andesite and basaltic andesite flows, and associated volcaniclastic units. Includes Rubio Peak Formation, and andesite of Dry Leggett Canyon

Lithology: andesite; basalt; intermediate volcanic rock; mafic volcanic rock; mixed clastic/volcanic

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

Pennsylvanian rocks, undivided; in Sangre de Cristo Mountains may include Sandia Formation, Madera Limestone, La Pasada, Alamitos, and Flechado Formations; elsewhere may include Bar-B, Nakaye, Red House, Oswaldo, and Syrena Formations

Lithology: sedimentary rock; medium-grained mixed clastic; carbonate

silicic flows, domes, and associated pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Lower Oligocene silicic (or felsic) flows, domes, and associated pyroclastic rocks and intrusions; includes Mimbres Peak Formation

Lithology: lava flow; tuff; felsic volcanic rock; conglomerate; pyroclastic

Lower Cretaceous, unidivided (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.3 % of this area

Lower Cretaceous, undivided; in northern Lea and Roosevelt Counties includes equivalents of Tucumcari Shale. In Cornudas Mountains includes Campogrande, Cox and other Washita Group formations, and the Boquillas Formation; Cenomanian. In the southwest includes Hell-To-Finish, U-Bar, and Mojado Formations which are equivalent to Bisbee Group of Arizona

Lithology: clastic; mixed clastic/carbonate

volcanic and some volcaniclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.2 % of this area

Volcanic and some volcaniclastic rocks, undifferentiated; lower Miocene and Upper Oligocene (younger than 29 Ma)

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

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

silicic pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 10 % 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

older alluvial deposits of upland plains and piedmont areas (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Older alluvial deposits of upland plains and piedmont areas, and calcic soils and eolian cover sediments of High Plains region; includes scattered lacustrine, playa, and alluvial deposits of the Tahoka, Double Tanks, Tule, Blanco, Blackwater Draw, and Gatuna Formations, the latter of which may be Pliocene at base; outcrops, however, are basically of Quaternary deposits; upper Quaternary to uppermost Pliocene(?)

Lithology: alluvium

Mississippian and Devonain rocks, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian) at surface, covers 0.3 % of this area

Mississippian and Devonian rocks, undivided; includes the Lake Valley Limestone, Caballero, Las Cruces, Rancheria, and Helms Formations and Escabrosa Group; Mississippian; the Onate, Sly Gap, Contadero Formations, and Percha Shale of south-central New Mexico, and Canutillo Formation of Northern Franklin Mountains and Bishops Cap area; Devonian

Lithology: carbonate; medium-grained mixed clastic

rhyolitic pyroclastic rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % 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