- Usage in publication:
-
- Williana member
- Modifications:
-
- Original reference
- Dominant lithology:
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- Gravel
- Clay
- Sand
- AAPG geologic province:
-
- Arkla basin
Summary:
Pg. 78 (fig. 6), 155-157. Williana member. The series of Pleistocene deposits in Grant and La Salle Parishes is divided into four members, their names corresponding to the four distinct depositional terrace surfaces, Williana (oldest), Bentley, Montgomery, and Prairie. Williana member consists of three transitional phases: coarse phase with lenticular masses of sands and gravels, predominantly sandy phase with local lenses of gravels, and upper silty clay phase with local sand lenses. Thickness 50 to 95 feet. Unconformably overlies Vicksburg sediments. [Age is Pleistocene.]
Well exposed along U.S. Highway 167 between Mosley Hill, 2 mi north of Williana and Bentley, Grant Parish, central LA.
Source: US geologic names lexicon (USGS Bull. 1200, p. 4246-4247).
- Usage in publication:
-
- Williana formation*
- Modifications:
-
- Revised
- AAPG geologic province:
-
- Gulf Coast basin
Summary:
Pg. 176-177, pl. 1. Williana formation. Rank raised to formation. Described in Rapides and Avoyelles Parishes, central Louisiana, where it overlies undifferentiated Fleming formation. [Age is Pleistocene.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 4246-4247).
- Usage in publication:
-
- Williana formation*
- Modifications:
-
- Areal extent
- AAPG geologic province:
-
- Gulf Coast basin
Summary:
Pg. 57, 63-65. Williana formation. In southwestern Louisiana, overlies Pliocene Foley formation (new). [Age is Pleistocene.]
Source: US geologic names lexicon (USGS Bull. 1200, p. 4246-4247).
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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).