INGEIS   05370
INSTITUTO DE GEOCRONOLOGIA Y GEOLOGIA ISOTOPICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Neoproterozoic to Early Palaeozoic events in the Sierra de San Luis: Implications for the Famatinian geodynamics in the Eastern Sierras Pampeanas (Argentina)
Autor/es:
SIEGESMUND, S.; STEENKEN, A.; WEMMER,K.; LÓPEZ DE LUCHI, M. G.
Lugar:
Kiel, Alemania
Reunión:
Simposio; Latin Amerika Colloquium; 2007
Institución organizadora:
University of Kiel
Resumen:
The application of the sensitive high-resolution ion microprobe (SHRIMP) U/Pb dating technique
to zircon and monazites of different rock types of the Sierra de San Luis provides an important insight into
the provenance and timing of deposition of the sedimentary precursors as well as the metamorphic and
igneous history of the various basement domains. Additional constraints on the Famatinian metamorphic
episode are provided by Pb/Pb stepwise leaching experiments on one staurolite and two garnet separates. The
results indicate that the sedimentary precursors of the Conlara Metamorphic Complex have a maximum age of
c. 590 Ma, whereas the Pringles Metamorphic Complex metasediments appear to be sourced from the
Pampean orogen in the Early Cambrian. Folded xenoliths within the c. 496 Ma El Peno´n pluton suggest that
the host Conlara Metamorphic Complex underwent a Pampean compression. From a 208Pb/232Th monazite age
of 478 Ma for a migmatite from the Nogolý´ Metamorphic Complex, the structural evolution of this basement
complex appears to be entirely post-Pampean. Onset of the Famatinian high-grade metamorphism, between c.
500 Ma and c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.. 590 Ma, whereas the Pringles Metamorphic Complex metasediments appear to be sourced from the
Pampean orogen in the Early Cambrian. Folded xenoliths within the c. 496 Ma El Peno´n pluton suggest that
the host Conlara Metamorphic Complex underwent a Pampean compression. From a 208Pb/232Th monazite age
of 478 Ma for a migmatite from the Nogolý´ Metamorphic Complex, the structural evolution of this basement
complex appears to be entirely post-Pampean. Onset of the Famatinian high-grade metamorphism, between c.
500 Ma and c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.c. 496 Ma El Peno´n pluton suggest that
the host Conlara Metamorphic Complex underwent a Pampean compression. From a 208Pb/232Th monazite age
of 478 Ma for a migmatite from the Nogolý´ Metamorphic Complex, the structural evolution of this basement
complex appears to be entirely post-Pampean. Onset of the Famatinian high-grade metamorphism, between c.
500 Ma and c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.208Pb/232Th monazite age
of 478 Ma for a migmatite from the Nogolý´ Metamorphic Complex, the structural evolution of this basement
complex appears to be entirely post-Pampean. Onset of the Famatinian high-grade metamorphism, between c.
500 Ma and c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.c.
500 Ma and c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.c. 450 Ma, follows a period of crustal extension on the western outboard of Gondwana and might
not be related directly to a Mid-Ordovician accretion of the Cuyania Terrane.