Where: La Rioja, Argentina (29.9° S, 68.0° W: paleocoordinates 39.0° S, 31.5° W)
• coordinate estimated from map
• small collection-level geographic resolution
When: Coloradian other zone, Los Colorados Formation (Agua de la Peña Group), Norian (228.0 - 208.5 Ma)
• "upper levels" of the formation; formation is considered to be latest Triassic in age
• bed-level stratigraphic resolution
Environment/lithology: fluvial-lacustrine; red siliciclastic sediments
• "The sequence was interpreted as deposited by moderately sinuous fluvial systems, which laterally interfinger with and grade into horizontally bedded flood-plain deposits. To the top of the sequence, thin-bedded sandstones and siltstones dominate and were deposited in ponds and as crevasse splays in overbank settings" (Arcucci et al. 2004)
• "The red beds of Los Colorados Formation are composed by successive thinning-upward cycles characterized by coarse- to medium-grained sandstones and fine-grained sandstones intercalated with siltstones, which progressively dominate to the upper part of the unit (Fig. 2). Coarse-grained sandstone beds are generally tabular in geometry, cross stratified (large-scale trough and tabular cross-bedding) and locally display horizontal lamination. Rounded pebbles and cobbles of chert, quartzite and metamorphic rocks commonly mantle set boundaries. Massive and horizontal laminated siltstones interfinger with rippled lamination fine-grained sandstones forms the uppermost portion of the cycles" (Arcucci et al. 2004)
Size class: macrofossils
Collection methods: PVL: Palaeontologia de Vertebrados, Instituto Miguel Lillo, Tucuman, Argentina
Primary reference: J. B. Desojo and A. M. Baez. 2007. Cranial morphology of the Late Triassic South American archosaur Neoaetosauroides engaeus: evidence for aetosaurian diversity. Palaeontology 50:267-276 [R. Butler/R. Butler]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 105695: authorized by Richard Butler, entered by Richard Butler on 24.02.2011
Creative Commons license: CC BY (attribution)
Taxonomic list
Show authors, comments, and common names
Reptilia |
Pseudosuchia - Stagonolepididae |
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