Also known as Headwaters of the Río Chico

Where: Chubut, Argentina (45.6° S, 68.4° W: paleocoordinates 47.9° S, 57.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Lago Colhué Huapi Formation (Chubut Group), Late/Upper Maastrichtian (70.6 - 66.0 Ma)

• Uppermost Lago Colhué Huapi Formation. Geological studies—particularly those of palynomorphs—support a late Maastrichtian age, probably close to the Cretaceous/Paleogene boundary, for the stratigraphic horizon in question (Vallati et al., 2016, 2020).

• bed-level stratigraphic resolution

Environment/lithology: fluvial; massive, black mudstone and sandstone

Size class: macrofossils

Preservation: soft parts

Collected in 2020

Collection methods: hydrochloric, hydroflouric,

• The samples were processed using the standard palynological procedures, with dilute hydrochloric acid (19%) and hydrofluoric acid (70%) to remove respectively carbonate and silicate mineral components, followed by treatment in hot hydrochloric acid (37%). Occasionally, a brief oxidation of the residue with nitric acid was necessary in order to improve the results. The palynological slides were studied under a Carl Zeiss KF 2 microscope, and the micrographs were taken with a digital Nikon Coolpix P2 camera at the Biostratigraphic Laboratory of the Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB). The slides are housed in the micropalaeontological repository at the UNPSJB, under the initials UNPSJB-MFP-CV181-221

Primary reference: P. Vallati, A. De Sosa Tomas, and G. Casal. 2020. A Maastrichtian terrestrial palaeoenvironment close to the K/Pg boundary in the Golfo San Jorge basin, Patagonia, Argentina. Journal of South American Earth Sciences 97(102401) [E. Vlachos/F. Aspromonte]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 234016: authorized by Evangelos Vlachos, entered by Franco Aspromonte on 12.03.2024

Creative Commons license: CC BY (attribution)