TS2.6 | Shift of accretionary to collisional orogens – from natural laboratories to conceptual and numerical models of mountain chains
EDI
Shift of accretionary to collisional orogens – from natural laboratories to conceptual and numerical models of mountain chains
Co-organized by GD4
Convener: Ícaro Dias da Silva | Co-conveners: Carmen Maria Aguilar Gil, Fabrizio Cocco

The shift from accretionary to collisional orogenic setting is elusive, as both scenarios can be laterally contemporaneous along a mountain chain, involving far-field, regional and local geological events that overprint in time and space. The conditions that trigger this shift can be influenced by inherited features of the lithosphere architecture of oceans and continents, including the amount of deformation accumulated during continental breakup and rifting and the thickness and geometry of the converging margins. Classic 2D models of accretionary and collisional belts have become insufficient to explain the diversity of geological aspects, namely structural, magmatic, metamorphic and sedimentary, which are critical to understand the paleogeography and the different geodynamic settings involved in the evolution of orogens through the Earth’s history. Modern geological mapping, including classic and modern field geological research using advanced laboratory techniques and geophysics, is highly relevant for conceiving 3D and 4D conceptual and numerical models, which may help to understand better the polycyclic evolution of the orogenesis. We encourage contributions that provide an integrated picture by combining results from active margins in accretionary and in collisional orogens, including lower crust-lithosphere-mantle interactions, highlighting the role of plate tectonics in the architecture of the continental crust, namely on the connection of deep to surface phenomena, including the development of marine and continental synorogenic basins to synorogenic compressional, transcurrent and extensional tectonic settings.
Special emphasis will be given to contributions that use different disciplines and innovative methods like (but not restricted to); field geology, structural geology, geochronology, petrochronology, geochemistry (including isotope geochemistry), geophysics, igneous and metamorphic petrology, stratigraphy, sedimentology, plate reconstructions, numerical and analogue modelling.

The shift from accretionary to collisional orogenic setting is elusive, as both scenarios can be laterally contemporaneous along a mountain chain, involving far-field, regional and local geological events that overprint in time and space. The conditions that trigger this shift can be influenced by inherited features of the lithosphere architecture of oceans and continents, including the amount of deformation accumulated during continental breakup and rifting and the thickness and geometry of the converging margins. Classic 2D models of accretionary and collisional belts have become insufficient to explain the diversity of geological aspects, namely structural, magmatic, metamorphic and sedimentary, which are critical to understand the paleogeography and the different geodynamic settings involved in the evolution of orogens through the Earth’s history. Modern geological mapping, including classic and modern field geological research using advanced laboratory techniques and geophysics, is highly relevant for conceiving 3D and 4D conceptual and numerical models, which may help to understand better the polycyclic evolution of the orogenesis. We encourage contributions that provide an integrated picture by combining results from active margins in accretionary and in collisional orogens, including lower crust-lithosphere-mantle interactions, highlighting the role of plate tectonics in the architecture of the continental crust, namely on the connection of deep to surface phenomena, including the development of marine and continental synorogenic basins to synorogenic compressional, transcurrent and extensional tectonic settings.
Special emphasis will be given to contributions that use different disciplines and innovative methods like (but not restricted to); field geology, structural geology, geochronology, petrochronology, geochemistry (including isotope geochemistry), geophysics, igneous and metamorphic petrology, stratigraphy, sedimentology, plate reconstructions, numerical and analogue modelling.