Woodring Loc. 76 - Madden Basin [lower Alhajuela Fm] (Miocene of Panama)

Where: Panama (9.2° N, 79.6° W: paleocoordinates 8.8° N, 77.8° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: lower Alhajuela Member (Alhajuela Formation), Middle Miocene (16.0 - 11.6 Ma)

• The Caimito Formation in Madden Basin includes both Oligocene and lower Miocene deposits. The thickness in the basin appears to be 450 m. The deposits now referred to the Caimito Formation were initially designated the Culebra Formation, Emperaqdor Limestone, Caimito Formation, and Gatun Formation. Five members are tentatively recognized in the Caimito Formation. Two members are grouped as the lower part, the upper three members form the upper part. In stratigraphic order these include: basal calcareous sandstone-siltstone member (200 m) overlies the Bohio Formation, or laps onto the Gatuncillo Formation; the pyroclastic-clay member (50 m); Chilibrillo Limestone member (150 m); calcareous sandstone member (30 m); Alhajuela Sandstone member (85 m). The lower part of the Caimito Fm (2 basal members) is late Oligocene, the upper part (3 upper members) is early Miocene; Alhajuela Sandstone revised to formation rank in subsequent publications. From the lower member of the formation.

• bed-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, fine-grained, coarse, tuffaceous sandstone

• No paleoenvironmental data reported.
• Massive, fine-coarse-grained tuffaceous sandstone.

Size class: macrofossils

Reposited in the USNM

Collection methods: surface (in situ),

Primary reference: W. P. Woodring. 1973. Geology and paleontology of canal zone and adjoing parts of Panama: Description of Tertiary mollusks (additions to gastropods, scaphopods, pelecypods: Nuculidae to Malleidae). United States Geological Survey Professional Paper 306(E):453-539 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 93043: authorized by Austin Hendy, entered by Austin Hendy on 24.12.2009

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for gastropoda and bivalvia.
Bivalvia
 Arcida - Arcidae
"Arca imbricata" = Lamarcka imbricata
"Arca imbricata" = Lamarcka imbricata Bruguière 1789 clam
 Pectinida - Pectinoidae
Amusium toulae, "Nodipecten clydonus n. sp." = Nodipecten colinensis, "Flabellipecten gatunensis" = Leopecten gatunensis
Amusium toulae Brown and Pilsbry 1911 scallop
"Nodipecten clydonus n. sp." = Nodipecten colinensis Hodson and Hodson 1927 scallop
"Flabellipecten gatunensis" = Leopecten gatunensis Toula 1909 scallop
SUBSPECIES: Flabellipecten gatunensis gatunensis
 Ostreida - Gryphaeidae
Hyotissa haitensis Sowerby 1850 oyster