Compositional evolution of orogenic sediment can be viewed as resulting from downstream mixing of detritus shed by several end-member sources to constitute the polygenic product deposited in foreland basins. Such a model of simple mixing, which does not consider modifications caused by physical and chemical processes through the sedimentary cycle, is applied here to first-cycle detritus presently produced in the Alps to assess sediment budgets and erosion patterns across the orogen. Using the same actualistic end members, the model is applied next to the recent past to reconstruct paleodrainage changes during major Pleistocene glaciations, and finally to a more remote past to tentatively infer erosional evolution and dispersal paths in the earliest Oligocene stages of Alpine morphogeny. A decisive factor of success in such an approach is the use of large multiple datasets displaying sufficiently distinct values in diverse end members. Forward mixing models can be made for bulk petrography and heavy-mineral suites as well as for any physical (grain density), geochemical (element concentrations, stable-isotope ratios), or geochronological parameters (apatite fission tracks, zircon U-Pb age spectra), and separately on sediments of various sizes and transport modes (suspended load and bedload). By comparing and integrating several independent estimates thus obtained we progressively gain a more robust insight about diverse geological processes, and may converge eventually toward a truer vision of our past.

Garzanti, E., Resentini, A., Vezzoli, G., Ando', S., Malusa', M., Padoan, M. (2012). Forward compositional modelling of Alpine orogenic sand. SEDIMENTARY GEOLOGY, 280, 149-164 [10.1016/j.sedgeo.2012.03.012].

Forward compositional modelling of Alpine orogenic sand

GARZANTI, EDUARDO;RESENTINI, ALBERTO
;
VEZZOLI, GIOVANNI;ANDO', SERGIO;MALUSA', MARCO GIOVANNI;PADOAN, MARTA
2012

Abstract

Compositional evolution of orogenic sediment can be viewed as resulting from downstream mixing of detritus shed by several end-member sources to constitute the polygenic product deposited in foreland basins. Such a model of simple mixing, which does not consider modifications caused by physical and chemical processes through the sedimentary cycle, is applied here to first-cycle detritus presently produced in the Alps to assess sediment budgets and erosion patterns across the orogen. Using the same actualistic end members, the model is applied next to the recent past to reconstruct paleodrainage changes during major Pleistocene glaciations, and finally to a more remote past to tentatively infer erosional evolution and dispersal paths in the earliest Oligocene stages of Alpine morphogeny. A decisive factor of success in such an approach is the use of large multiple datasets displaying sufficiently distinct values in diverse end members. Forward mixing models can be made for bulk petrography and heavy-mineral suites as well as for any physical (grain density), geochemical (element concentrations, stable-isotope ratios), or geochronological parameters (apatite fission tracks, zircon U-Pb age spectra), and separately on sediments of various sizes and transport modes (suspended load and bedload). By comparing and integrating several independent estimates thus obtained we progressively gain a more robust insight about diverse geological processes, and may converge eventually toward a truer vision of our past.
Articolo in rivista - Articolo scientifico
Provenance analysis; Sediment generation; Heavy minerals; Grain density; Geochemistry; River Dora Baltea; River Po; River Rhône
English
2012
280
149
164
none
Garzanti, E., Resentini, A., Vezzoli, G., Ando', S., Malusa', M., Padoan, M. (2012). Forward compositional modelling of Alpine orogenic sand. SEDIMENTARY GEOLOGY, 280, 149-164 [10.1016/j.sedgeo.2012.03.012].
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/29596
Citazioni
  • Scopus 85
  • ???jsp.display-item.citation.isi??? 81
Social impact