Geologic units in Lea county, New Mexico

Ogallala Formation (Lower Pliocene to middle Miocene) at surface, covers 48 % of this area

Alluvial and eolian deposits, and petrocalcic soils of the southern High Plains. Locally includes Qoa.

Eolian and piedmont deposits (Holocene to middle Pleistocene) at surface, covers 32 % of this area

Interlayered eolian sands and piedmont-slope deposits along the eastern flank of the Pecos River valley, primarily between Roswell and Carlsbad. Typically capped by thin eolian deposits.

Older alluvial deposits of upland plains and piedmont areas, and calcic soils and eolian cover sediments of High Plains region (Middle to lower Pleistocene) at surface, covers 8 % of this area

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.

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

Eolian deposits.

Piedmont alluvial deposits (Holocene to lower Pleistocene) at surface, covers 5 % 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 0.4 % of this area

Alluvium

Lacustrine and playa-lake deposits (Holocene) at surface, covers 0.2 % of this area

Includes associated alluvial and eolian deposits of major lake basins.

Upper Chinle Group, Garita Creek through Redonda Formations, undivided (Upper Triassic) at surface, covers 0.2 % of this area

Upper Chinle Group, Garita Creek through Redonda Formations, undivided

Blackwater Draw Formation (Pleistocene) at surface, covers < 0.1 % of this area

Blackwater Draw Formation

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

Sand sheet deposits

Playa (Quaternary) at surface, covers < 0.1 % of this area

Playa

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

Sand deposits, undivided

Ogallala Formation (Pliocene to Miocene) at surface, covers < 0.1 % of this area

Ogallala 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.

Leona Formation (Pleistocene) at surface, covers < 0.1 % of this area

Leona Formation

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

Alluvium