Mallin Quemado, Neuquen Province, MQ-III-40 (Jurassic of Argentina)

Where: Argentina (38.6° S, 70.1° W: paleocoordinates 36.8° S, 32.4° W)

• coordinate estimated from map

When: Alternans ammonoid zone, Pichi Moncol Member (Vaca Muerta Formation), Late/Upper Tithonian (150.8 - 145.0 Ma)

• The Vaca Muerta Fm. in transect MQ-III, although not observed up to its uppermost part (locally assigned to the Koeneni Z.) shows the three characteristic lithostratigraphic subdivisions, from below: the Portada Covunco, Los Catutos and Pichi Moncol (pars) members.

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, sandy shale

• Palaeogeographically the Sierra Vaca Muerta has a position close to the depocentre area of the basin.
• In transect MQ-III, the deposits of the Portada Covunco Mb. show a monotonous succession of black shales and sandy shales, rich in organic matter with thin intercalations of calcareous lutite, laminated calcareous sandstones, and wacky sandstones. Upwards in the succession of transect MQ-III carbonate facies dominate, consisting of marls and marly limestones with intercalations of black shales (Los Catutos Mb.), then culminating with a partial exposure of the Pichi Moncol Mb. represented by a domain of sandy shales showing variable contents of organic matter.

Size class: macrofossils

Preservation: cast, original aragonite

Primary reference: A. C. Garrido, H. Parent, and L. Brambilla. 2018. Tithonian stratigraphy and ammonite fauna of the Vaca Muerta Formation in Mallín Quemado (Neuquén Basin, Argentina), with remarks on the Andean chronostratigraphy. Volumina Jurassica XVI(1):1-26 [A. Kocsis/M. Gomez Correa]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 200701: authorized by Adam Kocsis, entered by Monica Alejandra Gomez Correa on 13.04.2019

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Cephalopoda
 Ammonitida - Himalayitidae
Corongoceras cf. mendozanum
Corongoceras cf. mendozanum Behrendsen 1892 ammonite