The Artesia Group and Salado Formation (Guadalupian/Ochoan) of Palo Duro Basin: Depositional Systems and Effects of Post-Permian Salt Dissolution

Access full-text files

Date

1987

Authors

Nance, Hardie Seay, 1948- 

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Interbedded red sandstone, siltstone, mudstone, anhydrite, and halite make up the Artesia Group and Salado Formation (Guadalupian/Ochoan) of the Palo Duro Basin. These deposits accumulated in a 10,000-mile2 low-relief epicontinental basin characterized by regional aridity and episodic, nearly basin-wide influx of marine-derived hypersaline waters. Various depositional environments developed, including eolian dunes, interdune areas, eolian flats, intermittent fluvial, mud flats, and broad, shallow brine pans. Clastic sources were in the west and northwest, while evaporites were derived from the south.

Eolian dune deposits exhibit medium to high angle (15°-35°) cross-bedded fine sandstone. Interdune areas accumulated rippled, bimodal, medium to very fine sandstone with frosted, spherical, medium sand grains and pedogenic structures. Eolian flats are characterized by deposits of very fine sandstone with poorly defined ripples. Intermittent fluvial deposition resulted in very fine sandstones and siltstones with graded bedding, ripples with mud drapes, and intraclasts. Mud-flat deposition produced mudstones with very disturbed ripples. Bedded halite and anhydrite precipitated in brine pan environments. Landward margins of brine pans feature deposits of sandstone and siltstone with displacive halite to chaotic halite-mudstone rock.

Artesia and Salado facies occur in a characteristic vertical sequence that comprises, from base to top, bedded anhydrite, bedded halite, chaotic halite-mudstone, sandstone, and siltstone with displacive halite, very disturbed rippled mudstone, intermittent fluvial, and eolian elastics. The sharp contacts between these shallowing-upward sequences suggest rapid transgressions.

Subsequent to upper Permian deposition, undetermined amounts of halite strata have been removed by dissolution, resulting in truncation of halite beds and collapse and diagenetic alteration in overlying strata.

Description

LCSH Subject Headings

Citation

Collections