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Mineral Resources > Online Spatial Data > Geology > by state > Colorado Geology

Geologic units in Montezuma county, Colorado

Glen Canyon Group and Chinle Fm (Phanerozoic | Mesozoic | Triassic Jurassic) at surface, covers 0.2 % of this area

In southwest, Glen Canyon Group consists of Navajo Sandstone, Kayenta Fm (red siltstone, shale, and sandstone) and Wingate Sandstone; Chinle is red siltstone

Lithology: sandstone; siltstone; shale

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

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit

Cliff House Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 9 % of this area

Lithology: sandstone

Dakota Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % 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

Dolores Fm (Phanerozoic | Mesozoic | Triassic) at surface, covers 2 % of this area

Red siltstone, shale, sandstone, and limestone-pellet conglomerate

Lithology: siltstone; shale; sandstone; conglomerate

Triassic and Jurassic sedimentary rocks in southeastern Utah (Early Jurassic) at surface, covers < 0.1 % of this area

Lithology: sandstone; mudstone; limestone

Gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.5 % of this area

Includes Broadway and Louviers Alluviums

Lithology: gravel; alluvium

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 21 % 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

Dakota Sandstone and Burro Canyon Fm (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 30 % of this area

Sandstone, shale, and conglomerate. In northwest and west-central: Lower Cretaceous. In southwest: Lower and Upper Cretaceous.

Lithology: sandstone; shale; conglomerate

Morrison Fm (Phanerozoic | Mesozoic | Jurassic) at surface, covers 1 % of this area

Variegated claystone, mudstone, sandstone, and local beds of limestone

Lithology: mudstone; sandstone; limestone

Menefee Fm and Point Lookout Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 10 % of this area

sandstone, shale, and coal; sandstone

Lithology: sandstone; shale; coal

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

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

Lithology: fine-grained mixed clastic; coal; limestone

Laramide intrusive rocks (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 1 % of this area

Mainly intermediate to felsic compositions; some mafic

Lithology: granitoid

Cretaceous (1) sedimentary rocks in southeastern Utah (Cretaceous) at surface, covers < 0.1 % of this area

Lithology: sandstone; shale

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

Alluvium; upper and middle Quaternary

Lithology: alluvium

Morrison Formation (Phanerozoic | Mesozoic | Jurassic) at surface, covers < 0.1 % of this area

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

Lithology: fine-grained mixed clastic; limestone

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

Includes Piney Creek Alluvium and younger deposits

Lithology: alluvium

Point Lookout Sandstone (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % 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

Mancos Shale--Juana Lopez Member (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 2 % of this area

Calcareous sandstone; a thin but persistent unit distinguished only locally

Lithology: sandstone; shale

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

Cliff House Sandstone; transgressive marine sandstone; Campanian

Lithology: sandstone; shale

Eolian deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 7 % of this area

Includes dune sand and silt and Peoria Loess

Lithology: dune sand; silt; loess

Morrison Fm, Summerville Fm, and Entrada Sandstone (Phanerozoic | Mesozoic | Jurassic) at surface, covers 8 % of this area

Summerville Fm: Shale and siltstone

Lithology: mudstone; sandstone

Landslide deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.2 % of this area

Locally includes talus, rock-glacier, and thick colluvial deposits

Lithology: landslide; talus; colluvium

Older gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.3 % of this area

Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest

Lithology: gravel; alluvium

Cutler Fm (Phanerozoic | Paleozoic | Permian) at surface, covers 1 % of this area

Arkosic sandstone, siltstone, and conglomerate

Lithology: sandstone; siltstone; conglomerate

Jurassic (2) sedimentary rocks in southeastern Utah (Late Jurassic) at surface, covers < 0.1 % of this area

Lithology: shale; sandstone; conglomerate

Quaternary alluvium and colluvium (Quaternary) at surface, covers < 0.1 % of this area

Lithology: alluvium; colluvium

Morrison, Wanakah, and Entrada Fms (Phanerozoic | Mesozoic | Jurassic) at surface, covers 5 % of this area

Lithology: mudstone; sandstone; limestone