INVESTIGADORES
ASTINI Ricardo Alfredo
artículos
Título:
Transfer of the Argentine Precordillera terrane from Laurentia: Constraints from detrital-zircon geochronology
Autor/es:
THOMAS, W.A.; ASTINI, R A.; MUELLER P.A.; GEHRELS, G.E.; WOODEN, J.L.
Revista:
GEOLOGY
Editorial:
Geological Society of America
Referencias:
Lugar: Boulder; Año: 2004 vol. 32 p. 965 - 968
ISSN:
0091-7613
Resumen:
ABSTRACT
Ages from U-Pb and 207Pb/206Pb analyses of detrital zircons from synrift sandstone in
the Lower Cambrian Cerro Totora Formation of the Argentine Precordillera have strong
similarities to those from late synrift sandstones in the Lower Cambrian Rome Formation
of southern Laurentia (Alabama). Ages of detrital zircons from the Cerro Totora sample
cluster at 1160?970 Ma (60% of analyzed zircons), 1490?1300 Ma (24%), and 1890?1640
Ma (16%). Ages from two Rome samples cluster at 1240?970 Ma (32% of analyzed zircons),
1540?1270 Ma (31%), 1840?1610 Ma (14%), 1970?1890 Ma (5%), and 2930?2310
Ma (18%). The ages of detrital zircons from the Rome and Cerro Totora sandstones are
consistent with sediment supply from the Grenville and older Proterozoic Laurentian
provinces, and the older cluster in the Rome sandstones corresponds in age to the Laurentian
Archean Superior province. Neither the Rome nor Cerro Totora samples include
components younger than Grenville, and the lack of zircons from distinctly Gondwanan
provinces is consistent with a Laurentian provenance. The detrital-zircon ages support
previous interpretations that the Precordillera was rifted from the Ouachita embayment
of Laurentia during Early Cambrian time and subsequently was transferred to
Gondwana.
q 2004 Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or editing@geosociety.org.2004 Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or editing@geosociety.org.
Geology; November 2004; v. 32; no. 11; p. 965?968; doi: 10.1130/G20727.1; 4 figures; Data Repository item 2004157.November 2004; v. 32; no. 11; p. 965?968; doi: 10.1130/G20727.1; 4 figures; Data Repository item 2004157.207Pb/206Pb analyses of detrital zircons from synrift sandstone in
the Lower Cambrian Cerro Totora Formation of the Argentine Precordillera have strong
similarities to those from late synrift sandstones in the Lower Cambrian Rome Formation
of southern Laurentia (Alabama). Ages of detrital zircons from the Cerro Totora sample
cluster at 1160?970 Ma (60% of analyzed zircons), 1490?1300 Ma (24%), and 1890?1640
Ma (16%). Ages from two Rome samples cluster at 1240?970 Ma (32% of analyzed zircons),
1540?1270 Ma (31%), 1840?1610 Ma (14%), 1970?1890 Ma (5%), and 2930?2310
Ma (18%). The ages of detrital zircons from the Rome and Cerro Totora sandstones are
consistent with sediment supply from the Grenville and older Proterozoic Laurentian
provinces, and the older cluster in the Rome sandstones corresponds in age to the Laurentian
Archean Superior province. Neither the Rome nor Cerro Totora samples include
components younger than Grenville, and the lack of zircons from distinctly Gondwanan
provinces is consistent with a Laurentian provenance. The detrital-zircon ages support
previous interpretations that the Precordillera was rifted from the Ouachita embayment
of Laurentia during Early Cambrian time and subsequently was transferred to
Gondwana.
q 2004 Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or editing@geosociety.org.2004 Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or editing@geosociety.org.
Geology; November 2004; v. 32; no. 11; p. 965?968; doi: 10.1130/G20727.1; 4 figures; Data Repository item 2004157.November 2004; v. 32; no. 11; p. 965?968; doi: 10.1130/G20727.1; 4 figures; Data Repository item 2004157.