Kosciusko formation

(Claiborne group), Irregularly bedded sand, clay, and some quartzite.
State Mississippi
Name Kosciusko formation
Geologic age Eocene
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand (Bed)
Unconsolidated > Fine-detrital > Clay (Bed)
Minor
Metamorphic > Metasedimentary > Metaclastic > Quartzite
Comments Secondary unit descriptions from USGS Lexicon website (MS002) and MS004: Dobys Bluff Tongue does not occur in Newton Co. Instead, the upper Kosciusko is composed of carbonaceous, nonfossiliferous shale. Upper portions are characterized by thin to medium bedded, tabular cross-beds, truncated by thin shale beds composed of light to dark gray clayey silt. Upper shaly portion has a maximum thickness of 88 ft. Disconformably underlies the Potterchitto Member of the Cook Mountain Formation. Lower portions of the Kosciusko are characterized by very coarse- to very fine grained quartz sand. Near the base, the unit is characterized by very coarse- to medium-grained, well-sorted quartz sand, with increasing percentages of glauconite toward the lower gradational contact with the Zilpha Formation. Thickness of the lower sands ranges from 56 ft to 160 ft. Surface exposures contain occurrences of petrified wood and well-lithified siltstone in the lower portion. Thick sequence of nonmarine sands and shales of the Kosciusko indicates constructive deltaic deposition. Measured section. Geologic map. Stratigraphic column (Merrill and others, 1985).
References

Moore, William Halsell, 1969, reprinted 1985, Geologic Map of Mississippi, Compiled by Bicker, A. R., Jr., a revision of the geologic map published by the MS Geological Survey in 1945 in cooperation with the USGS, revised from data submitted by Dr. E. E. Russell of MS State University from published reports of the MS Geological Survey and from field revisions, Mercury Maps Inc., Jackson, MS., scale 1:500,000.

USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/

https://ngmdb.usgs.gov/Geolex/search

Merrill, R.K., Sims, J.J., Jr., Gann, D.E. and Liles, K.J., 1985, Newton County geology and mineral resources [Mississippi]: Mississippi Office of Geology Bulletin, no. 126, 108 p.

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Counties Attala - Carroll - Clarke - DeSoto - Grenada - Holmes - Jasper - Lafayette - Lauderdale - Leake - Marshall - Montgomery - Neshoba - Newton - Panola - Quitman - Scott - Tallahatchie - Tate - Tunica - Yalobusha