Arroyo Cochicó / Mina Zitro (Lower Section) (Miocene of Argentina)

Where: Mendoza, Argentina (35.0° S, 68.5° W: paleocoordinates 35.4° S, 64.7° W)

• coordinate estimated from map

When: Aisol Formation, Middle Miocene (16.0 - 11.6 Ma)

• Garrido, et al. 2014: It's Aisol Fm in the literature (Gonzalez Díaz, 1972; Sepulveda et al., 2000) but needs verification.

•Btw they re-defined the Aisol FM and it's Early Miocene for their area of study

• member-level stratigraphic resolution

Environment/lithology: terrestrial; sandstone

• The lower section (LS) of the profile is composed mainly of medium to fine-grained sandstones predominantly grey, reddish, yellow, and less frequently pale green; the entire bed is roughly sub-horizontal. The sandstones are calcite-cemented and the entire bed has strong cross- stratification (Fig. 2), with higher angles towards the middle and upper parts of the section. Between the sandstones, levels of reddish to brownish, fine siltstones are interbedded. The thickness of the siltstone levels is larger towards the lower part of the section. In contrast, towards the upper part, reddish to greenish siltstones intraclasts are frequently found within the sandstones (Fig. 2). The intraclasts are variable in size and their surfaces are mostly rounded. Fossil wood and vertebrate remains are common in different parts of the LS. With the exception of the bones found in the siltstone, other material is highly eroded, showing signals of transportation and corrosion of biological organisms. In the area of the profile, the LS is approximately 15 m thick. The base, however, was not observed; it is covered by recent deposits.

Size class: macrofossils

Collection methods: Museo de Historia Natural de San Rafael, Mendoza, Argentina

Primary reference: A. M. Forasiepi, A. G. Martinelli, M. S. Fuente, S. Dieguez, and M. Bond. 2011. Paleontology and stratigraphy of the Aisol Formation (Neogene), San Rafael, Mendoza. Cenozoic Geology of the Central Andes of Argentina 135-154 [E. Vlachos/E. Vlachos]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 189522: authorized by Evangelos Vlachos, entered by Evangelos Vlachos on 25.10.2017, edited by Miranta Kouvari

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Testudines - Pantestudinidae
Chelonoidis sp. Fitzinger 1835 turtle
MHNSR- PV1024, partial shell, large size
Aves
 Cariamae - Phorusrhacidae
Phorusrhacidae indet. Ameghino 1889 terror bird
MACN-PV18602, right tarsometatarsus
 Rheiformes - Rheidae
"Pterocnemia cf. mesopotamica" = Rhea
"Pterocnemia cf. mesopotamica" = Rhea rhea
see also Agnolin y Noriega, 2012
Mammalia
 Xenarthra - Mylodontidae
Mylodontinae indet. Gill 1872 edentate
MACN-PV18605, right astragalus