LGS 9 formerly Locality #9 - Logansport Formation (Paleocene to of the United States)

Also known as M 76

Where: DeSoto County, Louisiana (31.6° N, 93.6° W: paleocoordinates 35.5° N, 75.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Logansport Formation (Midway Group), Danian to Danian (66.0 - 56.0 Ma)

• 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.

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified, concretionary, calcareous siltstone

• No paleoenvironmental data stated. Appears to be a shallow shelfal environment. Enterer has designated it as "offshore siliciclastic".
• Fossils occur in calcareous siltstone concretions.

Size classes: macrofossils, mesofossils

Preservation: concretion

Collection methods: Collected by LaBlanc and Barry (1939).

Primary reference: R. 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]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 52198: authorized by Austin Hendy, entered by Austin Hendy on 30.07.2005, edited by Laurie Eccles

Creative Commons license: CC BY (attribution)

Taxonomic list

• Antiquated nomenclature. Reviewed by LaBlanc (1942), and some names are validated by Toulmin (1977).
Bivalvia
 Cardiida - Tellinidae
Tellina estellensis1 tellin clam
Gastropoda
 Cerithioidea - Turritellidae
Turritella "sp. A" Lamarck 1799 turret shell
Turritella "sp. B" Lamarck 1799 turret shell
Turritella "sp. L"2 Lamarck 1799 turret shell
 Neogastropoda - Volutidae
Athleta petrosa Conrad 1833 volute
 Neogastropoda - Costellariidae
 Caenogastropoda - Fasciolariidae