U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Yazoo

Usage:

Yazoo Clay of Jackson Group (AL*,LA*,MS*)
Yazoo Formation of Jackson Group (AL*,LA*,MS*)
Yazoo Formation (TX)


Subunits:

(alphabetical): Cocoa Sand Member (AL*,MS*), North Twistwood Creek Clay Member (AL,MS) or North Twistwood Creek Member (AL*,MS*), Pachuta Marl Member (AL*,MS*), Shubuta Clay Member (MS) or Shubuta Member (AL*,LA?,MS*), Tullos Member (LA), Verda Member (LA).


Geologic age:

early Tertiary (late Eocene)*


Type section, locality, area and/or origin of name:

Named from exposures in bluff of Yazoo River at Yazoo City, Yazoo Co., MS (US geologic names lexicons, USGS Bull. 896, 1200).


AAPG geologic province:

Mid-Gulf Coast basin*
Gulf Coast basin*
Arkla basin


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).