Unit A (90-140 m) [Lopez de Bertodano Fm] (Cretaceous of Antarctica)

Where: Antarctica (64.2° S, 57.8° W: paleocoordinates 62.5° S, 68.2° W)

• coordinate stated in text

• local area-level geographic resolution

When: Lopez de Bertodano Formation, Early/Lower Maastrichtian (70.6 - 66.0 Ma)

• STRATIGRAPHIC RELATIONS: From the Lopez de Bertodano Fm, which is unconformably overlain by glacigenic diamictites and by the James Ross Island Volcanic Group. AGE: Early Maastrichtian, on the basis of ammonite biostratigraphy. STRATIGRAPHIC POSITION: From a the lower (90-140 m) part of Unit A.

• group of beds-level stratigraphic resolution

Environment/lithology: coastal; lithified, silty sandstone and lithified sandstone

• ENVIRONMENT: Shallow siliciclastic marine setting.
• SPECIFIC LITHOLOGY: Silty sandstones and sandstones. LITHIFICATION: Poorly lithified, on the basis of figured images.

Size class: macrofossils

Preservation: cast, mold/impression

Collection methods: surface (in situ),

• COLLECTOR: E. B. Olivero, D. R. Martinioni, and F. J. Mussel. REPOSITORY: Not stated, but presumably the Centro de Investigaciones en Recurso Geologicos (CIRGEO)..

Primary reference: E. B. Olivero, D. R. Martinioni, and F. J. 1992. Upper Cretaceous sedimentology and biostratigraphy of western Cape Lamb (Vega Island, Antarctica). Implications of sedimentary cycles and evolution of the basin. Geologia de la Isla James Ross 47-166 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 83551: authorized by Austin Hendy, entered by Austin Hendy on 22.08.2008

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: COVERAGE: Exhaustive for ammonoidea, bivalvia, and gastropoda. Other taxa listed under coarser taxonomic groupings. NOMENCLATURE: Not an authoritative publication, but with fairly modern nomenclature and species-resolution identifications where listed.
Malacostraca
 Decapoda -
Decapoda indet. Latreille 1802 decapod
Sedentaria
 Sabellida - Serpulidae
Bivalvia
 Trigoniida - Myophorelloidae
"Eselaevitrigonia regina" = Laevitrigonia (Eselaevitrigonia)
"Eselaevitrigonia regina" = Laevitrigonia (Eselaevitrigonia) clam
 Pholadomyida - Pholadomyidae
 Hiatellida - Hiatellidae
Panopea sp. Menard 1807 clam
 Cardiida - Lahillidae
Lahillia sp. Cossmann 1899 clam
 Cardiida - Veneridae
? Cyclorisma sp. Dall 1902 venus clam
 Arcida - Cucullaeidae
Cucullaea sp. Lamarck 1801 clam
 Ostreida - Gryphaeidae
"Pycnodonte cf. vesiculosa" = Pycnodonte (Phygraea) vesicularis vesiculosa
"Pycnodonte cf. vesiculosa" = Pycnodonte (Phygraea) vesicularis vesiculosa Sowerby 1822 oyster
 Ostreida - Pinnidae
Pinna sp. Linnaeus 1758 oyster
 Pectinida - Entoliidae
Entolium sp. Meek 1865 scallop
 Mytilida - Mytilidae
Cephalopoda
 Ammonitida - Kossmaticeratidae
Maorites tuberculatus Howard 1958 ammonite
Maorites weddelliensis Macellari 1986 ammonite
 Nautilida - Nautilidae
Eutrephoceras sp. Hyatt 1894