Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times

The Sierras de Cordoba Metasedimentary Series consists of marbles and metasiliciclastic rocks of Ediacaran to early Cambrian age (ca. 630 and 540 Ma) that underwent high-grade metamorphism during the collisional Pampean orogeny in the early Cambrian. The ages of the marbles were determined from the...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Murra, Juan A., Casquet, César, Locati, Francisco, Galindo, Carmen, Baldo, Edgardo G., Pankhurst, Robert J., Rapela, Carlos Washington
Formato: Articulo
Lenguaje:Inglés
Publicado: 2016
Materias:
Ciencias Naturales
Geología
Ediacaran carbonates
Sr-isotope blind dating
U–Pb SHRIMP zircon geochronology
Sierras Pampeanas
SW Gondwana
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/128874
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-128874
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Naturales
Geología
Ediacaran carbonates
Sr-isotope blind dating
U–Pb SHRIMP zircon geochronology
Sierras Pampeanas
SW Gondwana
spellingShingle Ciencias Naturales
Geología
Ediacaran carbonates
Sr-isotope blind dating
U–Pb SHRIMP zircon geochronology
Sierras Pampeanas
SW Gondwana
Murra, Juan A.
Casquet, César
Locati, Francisco
Galindo, Carmen
Baldo, Edgardo G.
Pankhurst, Robert J.
Rapela, Carlos Washington
Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
topic_facet Ciencias Naturales
Geología
Ediacaran carbonates
Sr-isotope blind dating
U–Pb SHRIMP zircon geochronology
Sierras Pampeanas
SW Gondwana
description The Sierras de Cordoba Metasedimentary Series consists of marbles and metasiliciclastic rocks of Ediacaran to early Cambrian age (ca. 630 and 540 Ma) that underwent high-grade metamorphism during the collisional Pampean orogeny in the early Cambrian. The ages of the marbles were determined from the Sr-isotope composition (blind dating) of screened samples of almost pure calcite marble and were further constrained with C- and O-isotope data and U–Pb SHRIMP detrital zircon ages of an interbedded paragneiss. Two groups of samples are recognised with Sr-isotope composition ca. 0.7075 and 0.7085 that are considered stratigraphically significant. The first is inferred early Ediacaran, the second late Ediacaran to early Cambrian. The Sierras de Cordoba Metasedimentary Series is correlated for the first time with marble-bearing metasedimentary series in several sierras to the west and north of Sierras de Cordoba (e.g., the Difunta Correa Sedimentary Sequence and the Ancajan Series), implying that all were probably parts of an originally extensive sedimentary cover. These series bear evidence of sedimentary sources in the Mesoproterozoic (and Paleoproterozoic) basement of the Western Sierras Pampeanas (part of the large MARA continental block) and farther west (Laurentia?). In terms of the age of limestones/marbles and detrital zircon patterns, the Sierras de Cordoba Metasedimentary Series differs strongly from the older section of late Ediacaran to early Cambrian Puncoviscana Formation of northwestern Argentina, which mostly outcrops in northern Sierra Chica and Sierra Norte, with sedimentary input from western Gondwana sources. The Sierras de Cordoba Metasedimentary Series and the Puncoviscana Formation were probably juxtaposed during the Pampean orogeny along a complex suture zone that was further folded and/or imbricated at mid-crustal depths. The peak of metamorphism was attained at 527 ± 2 Ma. According to the evidence found here most of the Sierras Pampeanas to the west of the Sierras de Cordoba were part of the lower colliding plate during the final amalgamation of SW Gondwana.
format Articulo
Articulo
author Murra, Juan A.
Casquet, César
Locati, Francisco
Galindo, Carmen
Baldo, Edgardo G.
Pankhurst, Robert J.
Rapela, Carlos Washington
author_facet Murra, Juan A.
Casquet, César
Locati, Francisco
Galindo, Carmen
Baldo, Edgardo G.
Pankhurst, Robert J.
Rapela, Carlos Washington
author_sort Murra, Juan A.
title Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
title_short Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
title_full Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
title_fullStr Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
title_full_unstemmed Isotope (Sr, C) and U–Pb SHRIMP zircon geochronology of marble-bearing sedimentary series in the Eastern Sierras Pampeanas, Argentina : Constraining the SW Gondwana margin in Ediacaran to early Cambrian times
title_sort isotope (sr, c) and u–pb shrimp zircon geochronology of marble-bearing sedimentary series in the eastern sierras pampeanas, argentina : constraining the sw gondwana margin in ediacaran to early cambrian times
publishDate 2016
url http://sedici.unlp.edu.ar/handle/10915/128874
work_keys_str_mv AT murrajuana isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT casquetcesar isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT locatifrancisco isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT galindocarmen isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT baldoedgardog isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT pankhurstrobertj isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
AT rapelacarloswashington isotopesrcandupbshrimpzircongeochronologyofmarblebearingsedimentaryseriesintheeasternsierraspampeanasargentinaconstrainingtheswgondwanamargininediacarantoearlycambriantimes
bdutipo_str Repositorios
_version_ 1764820451640475648

Ejemplares similares