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Geological Evolution of the Central Andes

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Geological Evolution of the Central Andes November, 5 to 9 -2018, Mendoza Argentina FIELD TRIP 3 Geological evolution of the Central Andes Instructor: Víctor Ramos Date: November 4-5, 2018 Program Stop 4: Picheuta (Snacks at lunchtime) Stop 11: Las Carreras The Permian-Triassic Choiyoi volcanism. Thrust front of the Frontal Mountain Range. Objetives New ideas of its global importance in Pa- Thick-skinned thrust belt and its time of buil- laeozoic extinction events. ding. Relationship with the Andean Precordi- The stops planned for these two days of llera. Gondwanic orogeny. field visits aim at showing the evolution of Stop 5: Polvaredas the Southern Central Andes, from the Lower Evidence of Post-Choiyoi magnetism rela- Stop 12: Rio Mendoza Palaeozoic to Quaternary. Special emphasis ted to extensional tectonics. Normal faults Initiation of rifting at the Cuyo basin. Typical will be given to the different structural styles and initiation of Gondwana break-up. location of Rio Mendoza formation and its of the units, in particular to those units with relationship with the Choiyoi Group. active petroleum systems. Participants will Stop 6: Tupungato get an updated view of the Andes evolution Tupungato volcano and the Pampean flat- Stop 13: Cacheuta (Snacks at lunchtime) in this latitude range and its relation to the slab. Horizontal subduction and its influence Cuyo basin, Rio Mendoza clusters, Cacheuta adjacent foreland basins. on the Triassic production basins. formation and the relationship with underl- ying and overlying units. Initial geological summary Stop 7: Puente del Inca Aconcagua fold-and-thrust belt. Thin-skin- Stop 14: Mariño First day (starting at 8.00AM) ned thrust belt and facies changes in the Synorogenic deposits, age and evolution of Stop 0: Cerro de la Gloria different thrust sheets. the Andean foreland basin. Un-roofing se- Growth strata from Pleistocene to Holocene. quences. Definition of wedge-top and foredeep within Stop 8: Aconcagua the Andean foreland basin system in this la- Facies changes and initiation of horizontal Stop 14: Aguada Pizarro titude. Neotectonics and Tectonic Inversion subduction. The evolution of Cenozoic Vol- Thrust front of the Andean Precordillera and in the Triassic depocenters of Cuyo basin. canic Arc and its resultant structure. Neotectonics. Characteristics of thrusts in the Andean Precordillera (Mendoza). Stop 1: Villavicencio Stop 9: Shelter Return to Mendoza Deposits of the Lower Palaeozoic, accre- Tordillo and Vaca Muerta formations in the end of excursion (6.00pm). tions and Cuyania evolution. Palaeozoic central sector of the Principal mountain ran- syn-orogenic deposits. ge. Proximity to the Cretaceous volcanic arc. Darwin’s shelter. Stop 2: Petrified forest Triassic deposits and Petrified Forest. Dinner and accommodation in Hotel Darwin’s theory about its origin and Today’s Ayelén (Penitentes) interpretation. Second day: (starting at 8.00am) Stop 3: Paramillos de Uspallata Stop 10: Penitentes Triassic Cuyo basin, stratigraphy of hydro- Thrust front of Aconcagua fold-and-thrust carbon plays. Tectonic Inversion structure belt. Historical controversies over some and the need of a suitable burying. thrust faults (upthrusts vs. overthrusts). Tel: (54 11) 5277 IAPG (4274) www.iapg.org.ar.
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