LGS 9 formerly Locality #9 - Logansport Formation: Danian - Thanetian, Louisiana

List of taxa
Where & when
Taphonomy & methods
Metadata & references
Taxonomic list
Gastropoda - Neogastropoda - Costellariidae
Orthosurcula longipersa
Gastropoda - Neogastropoda - Volutidae
Athleta petrosa (Conrad 1833)
Gastropoda - Naticidae
Polinices harrisii
Gastropoda - Turritellidae
Turritella informal sp. A Lamarck 1799
Turritella informal sp. B Lamarck 1799
Turritella informal sp. L Lamarck 1799
Palmer and Brann 1965
Bivalvia - Cardiida - Tellinidae
Tellina estellensis
Barry and LeBlanc 1942
see common names

Country:United States State/province:Louisiana County:DeSoto
Coordinates: 31.6° North, 93.6° West (view map)
Paleocoordinates:35.5° North, 75.2° West
Basis of coordinate:based on nearby landmark
Altitude:280 feet
Geographic resolution:outcrop
Period:Paleogene Epoch:Paleocene
10 m.y. bin:Cenozoic 1
Key time interval:Danian - Thanetian
Age range of interval:66.00000 - 56.00000 m.y. ago
Geological group:Midway Formation:Logansport
Stratigraphic resolution:bed
Stratigraphy comments: JAS has updated the age of this collection. "Logansport" was noted as a preoccupied name by Palmer and Brann (1965), who instead used the name "Halls Summit". Some confusion about the age of collections from this reference. While text states them to be Eocene, the Wilcox Group is in fact late Paleocene. No finer lithostratigraphic designation is stated in text, but Toulmin (1977) reports many of LeBlanc's taxa as belonging to the Logansport Formation of Sabine Parish, Louisiana. Logansport Formation lies betweent the Naborton and Hall Summit Formations, all of Thanetian age, and underlies further the Ypresian (Earliest Eocene) Marthaville, Pendleton and Sabinetown Formations.
Lithology and environment
Primary lithology:concretionary lithified calcareous siltstone
Includes fossils?Y
Lithology description: Fossils occur in calcareous siltstone concretions.
Geology comments: No paleoenvironmental data stated. Appears to be a shallow shelfal environment. Enterer has designated it as "offshore siliciclastic".
Modes of preservation:body,concretion
Size of fossils:macrofossils,mesofossils
Collection methods and comments
Collection methods:field collection
Reason for describing collection:biostratigraphic analysis
Collection method comments: Collected by LaBlanc and Barry (1939).
Taxonomic list comments:Antiquated nomenclature. Reviewed by LaBlanc (1942), and some names are validated by Toulmin (1977).
Also known as:M 76
Database number:52198
Authorizer:A. Hendy, J. Sessa Enterer:A. Hendy, L. Eccles
Modifier:L. Eccles Research group:GCP,marine invertebrate
Created:2005-07-30 17:27:33 Last modified:2013-11-25 13:37:23
Access level:group members Released:2010-07-30 17:27:33
Creative Commons license:CC BY
Reference information

Primary reference:

14033.1% 21600R. J. LeBlanc and J.O. Barry. 1941. Fossiliferous localities of Midway Group in Louisiana. Bulletin of the American Association of Petroleum Geologists 25(4):734-738 [A. Miller/A. Hendy/A. Hendy]

Secondary references:

35012 J. O. Barry and R. J. LeBlanc. 1942. Lower Eocene Faunal Units of Lousiana. Geological Bulletin of the state of Louisiana Dept. of Conservation (23)1-208 [J. Sessa/L. Eccles/L. Eccles]
11845 K. V. Palmer and D. C. Brann. 1965. Catalogue of the Paleocene and Eocene mollusca of the southern and eastern United States. Part 1. Pelecypoda, Amphineura, Peteropoda, Scaphopoda and Cephalopoda. Bulletins of American Paleontology 48:1-471 [M. Kosnik/M. Kosnik/J. Alroy]
11846 K. V. Palmer and D. C. Brann. 1966. Catalogue of the Paleocene and Eocene Mollusks of the Southern and Eastern United States Part II. Gastropoda. Bulletins of American Paleontology 48:471-1057 [M. Kosnik/M. Kosnik/J. Sessa]