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

Geologic units in San Juan county, New Mexico

[Additional scientific data in this geographic area]

intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.3 % of this area

Tertiary intrusive rocks; undifferentiated

Lithology: plutonic rock (phaneritic)

Mancos Shale, upper part (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 7 % of this area

Mancos Shale, Upper part

Lithology: shale; fine-grained mixed clastic

continental red beds (Phanerozoic | Mesozoic | Triassic) at surface, covers 0.1 % of this area

Triassic rocks, undivided; continental red beds

Lithology: medium-grained mixed clastic

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

Landslide deposits and colluvium

Lithology: landslide; colluvium

Menefee Formation (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 12 % of this area

Menefee Formation; mudstone, shale, and sandstone; coal-bearing

Lithology: fine-grained mixed clastic; coal; limestone

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

Animas Formation (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 0.3 % of this area

Animas Formation; in northeast San Juan Basin

Lithology: clay or mud; tuff; clastic

Pictured Cliffs Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 2 % of this area

Pictured Cliffs Sandstone; prominent cliff-forming marine sandstone

Lithology: sandstone; mudstone

Nacimiento Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 23 % of this area

Nacimiento Formation; Paleocene, San Juan Basin

Lithology: sandstone; shale; conglomerate

San Jose Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 8 % of this area

San Jose Formation; Eocene, San Juan Basin

Lithology: medium-grained mixed clastic

Dakota Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.9 % 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

undivided, Upper Cretaceous (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % 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

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

Mancos Shale, Lower part

Lithology: shale; fine-grained mixed clastic

Chinle Group (Phanerozoic | Mesozoic | Triassic) at surface, covers < 0.1 % 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

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 4 % of this area

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

Lithology: shale; fine-grained mixed clastic

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

Cliff House Sandstone; transgressive marine sandstone; Campanian

Lithology: sandstone; shale

Mesaverde Group (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 2 % 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

Point Lookout Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 1 % of this area

Point Lookout Sandstone; 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; Santonian - Campanian

Lithology: sandstone; arkose

Rock Point Formation of Chinle Group (Phanerozoic | Mesozoic | Triassic) at surface, covers 0.4 % of this area

Rock Point Formation of Chinle Group; Upper Triassic. May locally include Lukachukai Member of Wingate Sandstone

Lithology: sandstone; siltstone

Kirtland and Fruitland Formations (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 16 % of this area

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

Lithology: sandstone; mudstone; coal

Morrison Formation (Phanerozoic | Mesozoic | Jurassic) at surface, covers 2 % of this area

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

Lithology: fine-grained mixed clastic; limestone

alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 4 % of this area

Alluvium; upper and middle Quaternary

Lithology: alluvium

San Rafael Group (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.5 % 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

Ojo Alamo Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Ojo Alamo Formation; Paleocene, San Juan Basin

Lithology: sandstone; shale; conglomerate

Chuska Sandstone (Phanerozoic | Cenozoic | Tertiary) at surface, covers 3 % of this area

Chuska Sandstone; restricted to Chuska Mountains

Lithology: sandstone

middle and upper Jurassic rocks, unidivided (Phanerozoic | Mesozoic | Jurassic) at surface, covers < 0.1 % of this area

Jurassic rocks, Middle and Upper, undivided

Lithology: clastic; sedimentary rock