Geologic units in Otero county, New Mexico

San Andres Formation (Guadalupian and Leonardian) at surface, covers 34 % of this area

Limestone and dolomite with minor shale. Guadalupian in south, in part Leonardian to north.

Yeso Formation (Leonardian) at surface, covers 12 % of this area

Sandstones, siltstones, anhydrite, gypsum, halite, and dolomite.

Upper Santa Fe Group (Middle Pleistocene to uppermost Miocene) at surface, covers 11 % of this area

Includes Camp Rice, Fort Hancock, Palomas, Sierra Ladrones, Arroyo Ojito, Ancha, Puye, and Alamosa Formations.

Piedmont alluvial deposits (Holocene to lower Pleistocene) at surface, covers 11 % of this area

Includes deposits of higher gradient tributaries bordering major stream valleys, alluvial veneers of the piedmont slope, and alluvial fans. May locally include uppermost Pliocene deposits.

Alluvium (Holocene to upper Pleistocene) at surface, covers 9 % of this area

Alluvium

Eolian deposits (Holocene to middle Pleistocene) at surface, covers 5 % of this area

Eolian deposits.

Gypsiferous eolian deposits (Holocene to middle Pleistocene) at surface, covers 4 % of this area

Gypsiferous eolian deposits.

Hueco Formation or Group (Wolfcampian) at surface, covers 3 % of this area

Limestone unit restricted to south-central area; Pendejo Tongue of Hueco Formation divides Abo Formation into upper and lower parts in Sacramento Mountains.

Lacustrine and playa-lake deposits (Holocene) at surface, covers 2 % of this area

Includes associated alluvial and eolian deposits of major lake basins.

Pennsylvanian rocks, undivided (Pennsylvanian) at surface, covers 2 % of this area

In Sangre de Cristo Mountains may include Sandia, Madera, La Pasada, Alamitos, and Flechado Formations; elsewhere may include Bar-B, Nakaye, Red House, Oswaldo, and Syrena Formations.

Abo Formation (Wolfcampian) at surface, covers 1 % of this area

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.

Mancos Shale (Cenomanian to Campanian) at surface, covers 1 % of this area

Divided into Upper and Lower parts by Gallup Sandstone.

Queen and Grayburg Formations (Guadalupian) at surface, covers 1.0 % of this area

Sandstone, gypsum, anhydrite, dolomite, and red mudstone.

Basaltic to andesitic lava flows (Holocene to middle Pleistocene) at surface, covers 0.7 % of this area

Flows south of Grants and west of Carrizozo are Holocene. Includes minor vent deposits.

Tertiary intrusive rocks of intermediate to silicic composition (Pliocene to Eocene) at surface, covers 0.6 % of this area

Includes monzonitic to granitic plutons, stocks, laccoliths, and porphyritic dikes in deeply eroded magmatic centers; and andesitic, dacitic, or rhyolitic plugs and dikes near cauldrons or stratovolcanoes. In the Latir field, fine-grained rhyolitic dikes commonly cut coarse-grained granitic plutons. Includes alkaline laccoliths, plugs, and dikes in Colfax County. North-trending dikes near Capitan include some mafic diabase dikes.

Middle Tertiary volcanic rocks, undifferentiated (Lower Miocene to upper Eocene) at surface, covers 0.4 % of this area

Includes the predominantly andesitic to dacitic stratovolcano complex at Sierra Blanca (Oligocene to upper Eocene) and many smaller outliers.

Bursum Formation (Lowermost Permian to uppermost Pennsylvanian) at surface, covers 0.2 % of this area

Shale, arkose, and limestone.

San Andres, Glorieta, and Yeso Formations, undivided (Guadalupian and Leonardian) at surface, covers 0.2 % of this area

San Andres, Glorieta, and Yeso Formations, undivided

Mississippian and Devonian rocks, undivided (Mississippian and Devonian) at surface, covers 0.2 % of this area

Includes Helms, Rancheria, Las Cruces, Lake Valley, and Caballero Formations and Escabrosa Group (Mississippian); Percha Shale, Contadero, Sly Gap, and Onate Formations of south-central New Mexico, and Canutillo Formation of northern Franklin Mountains and Bishops Cap area (Devonian).

Upper and lower Cretaceous rocks of east-central and northeast New Mexico (Cenomanian and Albian) at surface, covers 0.2 % of this area

Consists of Dakota Group, which includes Romeroville Sandstone (Cenomanian), Pajarito Shale, and Mesa Rica Sandstone (Albian); the underlying Tucumcari Shale (Albian) in Tucumcari area and Glencairn Formation (Albian) in Union County.

Artesia Group (Guadalupian) at surface, covers 0.2 % of this area

Shelf facies forming broad south-southeast trending outcrop from Glorieta to Artesia area; includes Tansill, Yates, Seven Rivers, Queen and Grayburg Formations (Guadalupian). May locally include Moenkopi Formation (Triassic) at top.

Silurian and Ordovician rocks, undivided (Silurian and Ordovician) at surface, covers 0.2 % of this area

Silurian and Ordovician rocks, undivided

Mesaverde Group (Campanian to Turonian) at surface, covers 0.2 % of this area

Includes Cliff House Sandstone, Menefee Formation, and Point Lookout Sandstone.

Lower part of Abo Formation (locally Virgilian to Upper Pennsylvanian) at surface, covers 0.2 % of this area

Lower part of Abo Formation

Cherry Canyon Formation (Guadalupian) at surface, covers 0.1 % of this area

Basin facies - sandstone, limestone, and shale.

Upper part of Abo Formation (Wolfcampian) at surface, covers < 0.1 % of this area

Upper part of Abo Formation

Lower Cretaceous, undivided (Lower Cretaceous) at surface, covers < 0.1 % of this area

In northern Lea and Roosevelt Counties includes equivalents of Tucumcari Shale; in Cornudas Mountains includes Campogrande and Cox Formations and Washita Group; at Cerro de Cristo Rey includes several formations of the Fredricksburg and Washita Groups, and the Boquillas Formation (Cenomanian); in the southwest includes Mojado, U-Bar (Aptian), and Hell-to-Finish Formations, whch are equivalent to Bisbee Group of Arizona.

Sandia Formation (Atokan) at surface, covers < 0.1 % of this area

Predominately clastic unit (commonly arkosic) with minor black shales, and limestone in lower part; map unit locally includes Morrowan Osha Canyon Formation in Sierra Nacimiento.

Chinle Group (Upper to middle Triassic) at surface, covers < 0.1 % of this area

Map unit includes Moenkopi Formation (Middle Triassic) at base in many areas; in eastern part of state the following five formations are mapped: TRr, TRb, TRt, TRg, and TRs.

Cutoff Shale (Leonardian) at surface, covers < 0.1 % of this area

In Brokeoff Mountains only.

Victorio Peak Limestone (Leonardian) at surface, covers < 0.1 % of this area

In Brokeoff Mountains only.

Tertiary mafic intrusive rocks (Pliocene to upper Eocene) at surface, covers < 0.1 % of this area

Includes many long basaltic andesite dikes of Oligocene age near Pie Town, Acoma, Riley, Chupadera, Truth or Consequences, Roswell, Raton, and Dulce; and several elongate or shoestring-like sills of basalt or basaltic andesite. Also includes basaltic necks of Pliocene age that dot the landscape northeast of Mount Taylor. Where dikes extend into Quaternary alluvium the contact is an unconformity.

Intertongued Mancos Shale and Dakota Sandstone of west-central New Mexico (Cenomanian) at surface, covers < 0.1 % of this area

Includes the Whitewater Arroyo Tongue of Mancos Shale and the Twowells Tongue of the Dakota.

Moenkopi Formation (Middle Triassic) at surface, covers < 0.1 % of this area

Moenkopi Formation

San Andres Limestone and Glorieta Sandstone (Guadalupian and Leonardian) at surface, covers < 0.1 % of this area

San Andres Limestone and Glorieta Sandstone

Mesoproterozoic granitic plutonic rocks (Mesoproterozoic) at surface, covers < 0.1 % of this area

Mainly 1.45 - 1.35 Ga megacrystic granites, generally weakly foliated except locally at their margins.

Permian and Pennsylvanian rocks, undivided (Permian and Pennsylvanian) at surface, covers < 0.1 % of this area

Includes Concha, Scherrer, Colina, Epitaph, and Earp Formations (Permian) and Horquilla Limestone (Permian to Pennsylvanian).

Seven Rivers Formation (Guadalupian) at surface, covers < 0.1 % of this area

Gypsum, anhydrite, salt, dolomite, and siltstone.

Paleogene sedimentary units (Paleogene) at surface, covers < 0.1 % of this area

Includes Baca, Galisteo, El Rito, Blanco Basin, Hart Mine, Love Ranch, Lobo, Sanders Canyon, Skunk Ranch, Timberlake, and Cub Mountain Formations.

Ordovician and Cambrian rocks, undivided (Ordovician and Cambrian) at surface, covers < 0.1 % of this area

Includes Montoya Formation (or Group), El Paso Formation, and Bliss Sandstone.

Mesoproterozoic sedimentary rocks (Mesoproterozoic) at surface, covers < 0.1 % of this area

Exposed in Sacramento Mountains, present in subsurface in southeastern New Mexico as De Baca Group.

Hueco Limestone (Permian; Wolfcamp Series) at surface, covers < 0.1 % of this area

Hueco Limestone

Alluvial fan deposits (Pleistocene and Holocene) at surface, covers < 0.1 % of this area

Alluvial fan deposits

Alluvium (Holocene) at surface, covers < 0.1 % of this area

Alluvium

Bolson deposits (Pleistocene and Holocene) at surface, covers < 0.1 % of this area

Bolson deposits

Mingus Formation (Pennsylvanian; Des Moines Series) at surface, covers < 0.1 % of this area

Mingus Formation

Sand sheet deposits (Holocene) at surface, covers < 0.1 % of this area

Sand sheet deposits