INVESTIGADORES
PAZOS Pablo Jose
artículos
Título:
The ichnogenus Dictyodora from Late Silurian deposits of central-western Argentina: Ichnotaxonomy, ethology and ichnostratigrapical perspectives from Gondwana
Autor/es:
PAZOS P. J.; ARTURO M. HEREDIA; FERNANDEZ D.E,; CAROLINA GUTIERREZ
Revista:
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2015
ISSN:
0031-0182
Resumen:
The association of trace fossils from the Late Silurian Río Seco de los Castaños Formation in central-western
Argentina (San Rafael Block) is mainly composed of Dictyodora, including Dictyodora scotica, Dictyodora tenuisDictyodora, including Dictyodora scotica, Dictyodora tenuis
and a new ichnospecies named Dictyodora atuelica. The latter shows a tendency to migrate to a deeper level ?Dictyodora atuelica. The latter shows a tendency to migrate to a deeper level ?
analogous to Dictyodora liebeana´s ? which reflects more sophisticated behavioural patterns. The DictyodoraDictyodora liebeana´s ? which reflects more sophisticated behavioural patterns. The Dictyodora
ichnospecies (one of the most diverse assemblages in Gondwana) coexists with Nereites. SEM observations
and EDS analyses suggest that the wall structure of Dictyodora could be the result of an activity other than the
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
and EDS analyses suggest that the wall structure of Dictyodora could be the result of an activity other than the
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
Nereites. SEM observations
and EDS analyses suggest that the wall structure of Dictyodora could be the result of an activity other than the
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
Dictyodora could be the result of an activity other than the
traditional suggestion of respiration, e.g., feeding. The succession, including some of the levels containing
Dictyodora, presents microbially induced sedimentary structures (MISS) that would indicate a photic zone.
This discovery favours previous deltaic interpretations instead of the deep-sea fan deposits traditionally
suggested for the Siluro-Devonian greywackes of the Cuyania terrane, and particularly for this unit. The abundant
This discovery favours previous deltaic interpretations instead of the deep-sea fan deposits traditionally
suggested for the Siluro-Devonian greywackes of the Cuyania terrane, and particularly for this unit. The abundant
, presents microbially induced sedimentary structures (MISS) that would indicate a photic zone.
This discovery favours previous deltaic interpretations instead of the deep-sea fan deposits traditionally
suggested for the Siluro-Devonian greywackes of the Cuyania terrane, and particularly for this unit. The abundant
Dictyodora, Nereites, Zoophycos and undermat miners ichnofossils, as well as the scarce arthropod trackways,
resemble older records in Europe and North America. The studied section is very well age-constrained, and the
autochthonous Gondwana ichnofauna permits to cast doubt on previous interpretations, suggesting that after
the Ordovician, microbial mats retreated to marginal marine environments and then spread later in the
Carboniferous. More importantly, the occurrence of Dictyodora and Nereites in beds that bear abundant wrinkle
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
resemble older records in Europe and North America. The studied section is very well age-constrained, and the
autochthonous Gondwana ichnofauna permits to cast doubt on previous interpretations, suggesting that after
the Ordovician, microbial mats retreated to marginal marine environments and then spread later in the
Carboniferous. More importantly, the occurrence of Dictyodora and Nereites in beds that bear abundant wrinkle
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
, Nereites, Zoophycos and undermat miners ichnofossils, as well as the scarce arthropod trackways,
resemble older records in Europe and North America. The studied section is very well age-constrained, and the
autochthonous Gondwana ichnofauna permits to cast doubt on previous interpretations, suggesting that after
the Ordovician, microbial mats retreated to marginal marine environments and then spread later in the
Carboniferous. More importantly, the occurrence of Dictyodora and Nereites in beds that bear abundant wrinkle
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
Dictyodora and Nereites in beds that bear abundant wrinkle
structures or records of biofilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodorafilms in someplaces is challengingwith regard to deep-sea interpretations. Dictyodora
is probably not a good stratigraphic indicator, and the provincialism suggested for this ichnogenus may be an
artefact of the lack of more complete records in Gondwana