D6 - San Ramon section (Paleocene of Argentina)

Where: Chubut, Argentina (42.7° S, 69.8° W: paleocoordinates 45.1° S, 58.8° W)

• coordinate estimated from map

When: Lefipán Formation, Danian (66.0 - 61.6 Ma)

• bed-level stratigraphic resolution

Environment/lithology: delta front; lithified mudstone

• During the early Danian coarsening-upward cycles reflect accumulation in tidal bars, mainly in a tide to waveinfluenced distal delta-front environment with high sedimentation rates. These deposits bear molluscan faunal associations indicative of recurrent changes from normal marine to low-salinity marine environments with low-oxygen, fine-grained, soupy substrates.
• This bed: Bioturbation - Heterolithic bedding

•The Lefipán Formation consists of marine to marginal marine, fossiliferous sandstones and mudstones with some intercalated coquinas and conglomerates.

Size class: microfossils

• Samples were marine (dinoflagellate cysts)and continental (spores, pollen grains, fungal remains, fresh water algae) palynomorphs.

Preservation: original sporopollenin

Collection methods: chemical,

• Slides are housed in the palynological collection of the Museo Paleontológico Egidio Feruglio, Trelew, Chubut, Argentina (MPEF-Palin)numbers 100 to 113.

Primary reference: V. D. Barreda, N. R. Cúneo, P. Wilf, E. D. Currano, R. A. Scasso and H. Brinkhuis. 2012. Cretaceous/Paleogene Floral Turnover in Patagonia: Drop in Diversity, Low Extinction, and a Classopollis Spike. PLoS ONE 7(12):e52455 [C. Jaramillo/J. Moreno]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 151458: authorized by Carlos Jaramillo, entered by Jessica Moreno on 03.10.2013

Creative Commons license: CC BY (attribution)

Taxonomic list

• Pollen terminology follows Punt et al. 2007.
Psilatricolpites
  -
Psilatricolpites inargutus Archangelsky 1973
Pinopsida
 Pinales - Podocarpaceae
 Pinales - Araucariaceae
 Pinales - Cheirolepidiaceae
Classopollis sp. Pflug 1953
Monocotyledoneae
 Arecales -
Spinizonocolpites hialinus Archangelsky and Zamaloa 1986
Arecipites sp. Nichols et al. 1973
  -
Pteridopsida
  -
Trilites "sp. 2" Erdtman and Couper 1947
Trilites volkheimerii Filatoff 1975
Laevigatosporites ovatus Wilson and Webster 1946
Cyathidites minor Couper 1953
Cyathidites australis Couper 1953
Peromonolites vellosus Partridge 1973
 Gleicheniales - Gleicheniaceae
  -
Deltoidospora sp. Miner 1935
Lycopsida
  -
  - Selaginellaceae
Ceratosporites equalis Cookson and Dettmann 1958
Bryopsida
  -
Magnoliopsida
  -
Senipites tercrassata Archangelsky 1973
Tricolporites "sp. 3" Cookson 1947
Dicotyledonae
 Theales - Dilleniidae
Magnoliopsida
  -
Haloragacidites harrisii Mildenhall and Harris 1971
Rhoipites minusculus Archangelsky 1973
Gemmatricolpites "sp. 1" van Hoeken-Klinkenberg 1964
 Magnoliales - Chloranthaceae
  -
Psilatricolporites salamanquensis Archangelsky and Zamaloa 1986
Rousea patagonica Archangelsky 1973
Retitricolporites "sp. 1" Van der Hammen and Wymstra 1964
 Gentianales - Apocynaceae
cf. Cricotriporites sp. Leidelmeyer 1966
cf. Cricotriporites
 Fabales - Fabaceae
Margocolporites sp. Ramanajuan 1966
 Malvales - Bombacaceae
 Proteales -
Triatriopollenites bertelsii Archangelsky 1973
Triatriopollenites lateflexus Archangelsky 1973
 Proteales - Proteaceae
Propylipollis cf. tenuiexinus Dettmann and Jarzen 1996
Echitriporites sp. Van der Hammen 1956
Lewalanipollis senectus Dettmann and Jarzen 1996
 Proteales -
Peninsulapollis gillii Dettmann and Jarzen 1988
Peninsulapollis cf. truswelliae Dettmann and Jarzen 1988
Proteacidites "sp. C" Cookson and Couper 1953
 Fagales -
Nothofagidites "sp. 1" Potonié 1960
Nothofagidites fuegiensis Menéndez and Caccavari 1975
  -
Tricolpites "sp. 1" Potonié 1960
Striatricolporites gamerroi Archangelsky 1973