Mudstone, shale, and sandstone; coal-bearing.
Coal-bearing units are Dilco and Gibson Coal Members; other members are Bartlett Barren, Dalton Sandstone, and Borrego Pass Sandstone (or Lentil).
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.
Includes the Whitewater Arroyo Tongue of Mancos Shale and the Twowells Tongue of the Dakota.
Alluvium
Regressive marine sandstone in McKinley and Sandoval Counties; the lower, Hosta Tongue, of Point Lookout is transgressive and is separated from main body by the Satan Tongue of Mancos Shale.
Includes minor vent deposits and small shield volcanoes. Flows are commonly interbedded in the Santa Fe and Gila Groups.
Mancos Shale, lower part
Includes Bidahochi Formation (Pliocene to upper Miocene), Picuris Formation (Miocene to Oligocene), Las Feveras Formation (Pliocene), lower Gila Group units in the southwest, and unnamed Pliocene unit in northwestern Socorro County.
Marine shale and mudstone.
Generally regressive marine sandstone.
Consists of Entrada Sandstone, Todilto and Summerville Formations, Bluff Sandstone, and locally Zuni Sandstone (or only Acoma Tongue of Zuni).
Zuni and Entrada Sandstones, undivided
Transgressive marine sandstone.
Satan Tongue of Mancos Shale
In Zuni Basin only; Pescado is chrono-stratigraphic equivalent of Juana Lopez Member of Mancos Shale.
Coal-bearing, primarily in the Fruitland.
Upper Jurassic nonmarine rocks.
Landslide deposits on western flanks of Socorro Mountains not shown for clarity.
Mulatto Tongue of Mancos Shale
Overlies Twowells Tongue of Dakota Sandstone; mapped only where Tres Hermanos Formation or the Atarque Sandstone is present; mapped as Kdr in parts of Socorro County.
Formerly designated as Lower Gallup Sandstone in the Zuni Basin.
Restricted to Chuska Mountains.
Mancos Shale, upper part
Limestone and dolomite with minor shale. Guadalupian in south, in part Leonardian to north.
Continental red beds.
San Juan Basin
Includes Oak Canyon, Cubero, and Paguate Tongues; includes Clay Mesa Tongue of Mancos Shale.
Texturally and mineralogically mature, high-silica quartz sandstone.
Divided into Upper and Lower parts by Gallup Sandstone.
Transgressive marine sandstone.
In southwest includes the basalt-bearing Broken Jug Formation.
Prominent cliff-forming marine sandstone.
Sandstones, siltstones, anhydrite, gypsum, halite, and dolomite.
Includes vent deposits.
Flows south of Grants and west of Carrizozo are Holocene. Includes minor vent deposits.
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.
San Juan Basin
Beartooth and Sarten Formations are in part Albian. Includes Virden Formation in northern Hidalgo County, Ringbone Formation in Hidalgo, Luna and Grant Counties, Mancos Shale in Silver City area.
Variably foliated granites and granitic gneisses; 1.71 - 1.65 Ga in northern New Mexico; 1.66 - 1.65 Ga in central and southern New Mexico.
Eolian deposits.
May locally include Wingate Sandstone.
Includes minor vent deposits. Flows are commonly interbedded in the Santa Fe and Gila Groups.
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.
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.
Mostly andesitic to dacitic strato volcanoes. Includes rhyolite lavas and tuffs in the Jemez Mountains, Volcanoes in Jemez Mountains and eastern Colfax County are upper Miocene. Mount Taylor and composite volcanoes in the Taos Plateau volcanic field are Pliocene.