Geodynamics of a Cordilleran Orogenic System: The Central Andes of Argentina and Northern Chile (Memoirs (Geological Society of America))

This memoir brings together results from a six-year, multidisciplinary study of the linkages among processes that have formed the highest, widest part of the Andean Cordilleran orogenic belt in northern Argentina and Chile. The region features a tectonically erosive forearc, protracted arc magmatism, a high-elevation hinterland plateau and strongly shortened retroarc thrust belt, and a Paleocene-Recent foreland basin system. Surface geology records spatially complex shortening, extension, mafic to felsic magmatism, hinterland basin development, elevation change, and regional foreland basin migration. Seismological and geodynamic studies demonstrate a complex, dynamic upper mantle marked by widespread foundering of dense lithosphere formed by magmatic and metamorphic processes beneath the hinterland. Diverse processes operating over the past 60 m.y. in the central Andes define a tectono-magmatic cycle with a periodicity of ca. 25-30 m.y., providing a new framework for interpreting Cordilleran orogenic systems worldwide.