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First Ordovician Foraminifera from South America: A Darriwilian (Middle Ordovician) fauna from the San Juan Formation, Argentina
(Micropaleontology Press, 2009-12)
The first Ordovician foraminifers in South America are described from Middle Ordovician (Darriwilian)strata of the upper part of the San Juan Formation, Argentina. The foraminifers are found together with conodonts of the ...
Middle Ordovician conodonts and graptolites at Los Cauquenes range, central Precordillera of San Juan, Argentina
(Asociación Paleontológica Argentina, 2013-07)
The Ordovician System is superbly represented in the Precordillera of western Argentina, at the Andean foothills. During the Middle Ordovician, an important paleogeographical rearrangement of depocenters and source areas ...
The palaeobiogeographical spread of the acritarch Veryhachium in the Early and Middle Ordovician and its impact on biostratigraphical applications
(Taylor & Francis Ltd, 2014-03)
The genus Veryhachium Deunff, 1954, is one of the most frequently documented acritarch genera, being recorded from the Early Ordovician to the Neogene. Detailed investigations show that Veryhachium species first appeared ...
Acritarchs of peri-Gondwana at the Lower and Middle Ordovician stage boundaries
(Instituto Superior de Correlación Geológica, 2003-08)
Although acritarchs have been studied mostly for stratigraphic purposes (often in sediments devoid of other fossils), their biostratigraphic potential has not yet been fully exploited in the Ordovician. While another group ...
Biostratigraphy and paleogeography of Middle-Late Ordovician palynomorphs from the Llanos Basin, Colombia
(Elsevier Science, 2021-03)
Diverse and moderately to well-preserved palynomorph assemblages, composed of 81 organic-walled phytoplankton species, belonging to 47 genera, and two chitinozoan species, were recorded from the Ordovician rocks of the ...
Middle Ordovician linguliformean microbrachiopods from western Argentina: new data and biogeographic implications
(Paleontological Society, 2021-04)
New linguliform microbrachiopods from the Middle Ordovician are described and illustrated. This fauna was recovered from the uppermost beds of the San Juan Formation in two sections of the Central Precordillera (Argentina), ...
Ordovician conodonts from Peru: new data and reappraisal - [Poster]
(Université Claude Bernard Lyon IFR, 2016-12)
Ordovician conodont faunas are poorly known from the northern part of the Central Andean Basin, in contrast with data from the northwest of Argentina and south of Bolivia, areas located in the southern part of the same ...
Stratigraphical distribution of the Ordovician conodont Erraticodon Dzik in Argentina
(Elsevier, 2013-08)
Three different species of the Ordovician genus Erraticodon Dzik are described and illustrated. E. patu Cooper is reported from the Lower-Midde Ordovician strata of the Acoite and Alto del Cóndor formations. E. cf. E. ...
Early Middle Ordovician evidence for land plants in Argentina (eastern Gondwana)
(Wiley Blackwell Publishing, Inc, 2010-10)
The advent of embryophytes (land plants) is among the most important evolutionary breakthroughs in Earth history. It irreversibly changed climates and biogeochemical processes on a global scale; it allowed all eukaryotic ...
Darriwilian (Middle Ordovician) δ13Ccarb chemostratigraphy in the Precordillera of Argentina: Documentation of the middle Darriwilian Isotope Carbon Excursion (MDICE) and its use for intercontinental correlation
(Elsevier Science, 2013-03)
Although documented from Estonia, Latvia, Sweden, eastern North America, and China, the Middle Ordovician (Darriwilian) positive δ13C excursion known as the MDICE has previously not been recognized with certainty in South ...