THE HIGHEST THE HIGHEST CENTRAL ANDES CENTRAL ANDES Victor A. Ramos Victor A. Ramos Laboratorio de Tectónica Laboratorio de Tectónica Andina Andina Universidad de Buenos Aires Universidad de Buenos Aires
Dec 14, 2015
THE HIGHESTTHE HIGHESTCENTRAL ANDESCENTRAL ANDES
Victor A. RamosVictor A. Ramos
Laboratorio de Tectónica AndinaLaboratorio de Tectónica AndinaUniversidad de Buenos AiresUniversidad de Buenos Aires
AconcaguaAconcagua
MercedarioMercedario
TupungatoTupungato
La RamadaLa Ramada
Cerro Aconcagua (6.965 m)Cerro Aconcagua (6.965 m)
Cerro Aconcagua (6.965 m)Cerro Aconcagua (6.965 m)
Pleistocene Volcano
VOLCÁN TUPUNGATOVOLCÁN TUPUNGATO(6.850 m)(6.850 m)
CENTRAL ANDESCENTRAL ANDES
ZONA DE BENIOFFZONA DE BENIOFFSUBHORIZONTALSUBHORIZONTAL
Cordillera PrincipalCordillera Principal
Cordillera FrontalCordillera Frontal
PrecordilleraPrecordillera
Sierras PampeanasSierras Pampeanas
ACONCAGUA FOLD AND THRUST BELTACONCAGUA FOLD AND THRUST BELT
Cegarra (1994)Cegarra (1994)
Juan Fern
ández Rid
ge
Juan Fern
ández Rid
ge
Sierras PampeanasSierras Pampeanas
BENIOFF ZONESBENIOFF ZONES
50 km
Mendoza
CórdobaSanJuan
BROKEN FORELAND BASINSBROKEN FORELAND BASINS
MAGNETOTELLURIC PROFIL OF SIERRAS PAMPEANASMAGNETOTELLURIC PROFIL OF SIERRAS PAMPEANAS
Booker et al. (2004)Booker et al. (2004)
PALEOZOIC TERRANES
Ramos (1994)Ramos (1994)
RÍO DE LA PLATACRATON
PAMPIA
CUYANIA
CHILENIA
PICHIDANGUI
TECTONIC EVOLUTION OF SIERRAS PAMPEANASTECTONIC EVOLUTION OF SIERRAS PAMPEANAS
COLLISIONCOLLISION
COLLISIONCOLLISION
COLLISIONCOLLISION
Quenardelle & Ramos (1999)Quenardelle & Ramos (1999)
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Rapela et al. (1998)Rapela et al. (1998)
Ramos (1988)Ramos (1988)
Based on:Based on:
• Gordillo (1984)Gordillo (1984)
• Patiño Douce (1987)Patiño Douce (1987)
• Jordan et al. (1988)Jordan et al. (1988)
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Rapela et al. (1998)Rapela et al. (1998)
METAMORPHISM:
M3: Low-P (2,5 to 4,0 Kb) Isothermal decompression
M2: High-T / Medium-P Regional metamorphism
M1: Medium grade Older foliation in garnets
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Rapela et al. (1998)Rapela et al. (1998)
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Age of high grade metamorphism:Age of high grade metamorphism: 1.- Migmatite with garnate where M2 has been established1.- Migmatite with garnate where M2 has been established with inherited zircon ageswith inherited zircon ages
U-Pb SHRIMP DATAU-Pb SHRIMP DATA
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Rapela et al. (1998)Rapela et al. (1998)
Last deformation D3:Last deformation D3: 2.- Monacite ages in granitoids2.- Monacite ages in granitoids
U-Pb SHRIMP DATAU-Pb SHRIMP DATA
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EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
GRANITOS PRECOLISIONALESGRANITOS PRECOLISIONALES
Rapela et al. (1998)Rapela et al. (1998)
PAMPEAN GRANITOIDSPAMPEAN GRANITOIDS
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Rapela et al. (1998)Rapela et al. (1998)
Tectonic setting of granitoidsTectonic setting of granitoids a) Small postectonic (post-D2)a) Small postectonic (post-D2) b) Metaluminous and peraluminous granitoidsb) Metaluminous and peraluminous granitoids
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Preorogenic granitoids (Early Cambrian)Preorogenic granitoids (Early Cambrian)
Rapela et al. Rapela et al. (1998)(1998)
Río SuquiaAscochinga
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
Postorogenic granitoids (Early Cambrian)Postorogenic granitoids (Early Cambrian)
Rapela et al. Rapela et al. (1998)(1998)
EASTERN SIERRAS PAMPEANASEASTERN SIERRAS PAMPEANAS
EARLY PALEOZOIC EARLY PALEOZOIC MAGMATIC ARCSMAGMATIC ARCSEAST OF CUYANIAEAST OF CUYANIA
• Late Proterozoic- Early Cambrian Late Proterozoic- Early Cambrian magmatic arc of eastern Sierras magmatic arc of eastern Sierras Pampeanas.Pampeanas.
• Late Cambrian - Ordovician magmaticLate Cambrian - Ordovician magmatic arc of western Sierras Pampeanas.arc of western Sierras Pampeanas.
• Ordovician magmatic arc of the Ordovician magmatic arc of the Famatina terrane.Famatina terrane.
The early Paleozoic is a period of The early Paleozoic is a period of accretion of different continental blocksaccretion of different continental blocks with development of magmatic arcs and with development of magmatic arcs and ophiolite obduction.ophiolite obduction.
Quenardelle y Ramos (1999)Quenardelle y Ramos (1999)
Pankhurst et al. (2000)Pankhurst et al. (2000)
WESTERN SIERRAS PAMPEANASWESTERN SIERRAS PAMPEANAS
PRE -, SYN -, AND POSTCOLLISIONAL GRANITOIDS
AA
CC
BB
DDFF
GGHH
EE
OPHIOLITE BELTSOPHIOLITE BELTS
• A. CalalasteA. Calalaste
• B. FiambaláB. Fiambalá
• C. Valle Fértil-C. Valle Fértil- Toro NegroToro Negro
• D. CortaderasD. Cortaderas
• E. Pie de PaloE. Pie de Palo
• F. Bosque AlegreF. Bosque Alegre
• G. VirorcoG. Virorco
• H. Athos PampaH. Athos Pampa
EARLYPALEOZOIC
BASAL TECTONITESBASAL TECTONITES
CUMULATOS IN GABBROS CUMULATOS IN GABBROS
Pillow-lavas in MORB tholeiitesPillow-lavas in MORB tholeiites
BASEMENT OF CUYANIA U-Pb in zircon ages
OlenellusOlenellus
LAURENTIAN FOSSILS
PROVENANCE OF THE CUYANIA SYNRIFT DEPOSITS
Corrected values after Finney (2004)
Ramos (2004)Ramos (2004)
ISOTOPIC CHARACTERISTICS OF CUYANIA
Groomet et al. (2003)Groomet et al. (2003)
COLLISION OF CUYANIA
Ramos (2004)Ramos (2004)
STAGES IN THE CUYANIA COLLISION
Ramos (2004)Ramos (2004)
PrecordilleraPrecordilleracarbonate platformcarbonate platform
Olistholiths Olistholiths
PRECORDILLERA FAMATINA
SHRIMP AGES OF K-BENTONITES AND GONDWANAN VOLCANIC ROCKS
Baldo et al. (2003)Baldo et al. (2003)
LAURENTIA GONDWANA
Many Thanks . . .Many Thanks . . .