caa a22 4500 606150048 CHVBK 20210128100537.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00531-014-1139-x doi (NATIONALLICENCE)springer-10.1007/s00531-014-1139-x U-Pb ages and Hf isotopic composition of zircons in Austrian last glacial loess: constraints on heavy mineral sources and sediment transport pathways [Elektronische Daten] [Gábor Újvári, Urs Klötzli] Loess sediments in Austria deposited ca. 30-20ka ago yield different zircon age signatures for samples collected around Krems (SE Bohemian Massif; samples K23 and S1) and Wels (halfway between the Bohemian Massif and the Eastern Alps; sample A16). Cathodoluminescence (CL) imaging reveals both old, multistage zircons with complex growth histories and inherited cores, and young, first-cycle magmatic zircons. Paleoproterozoic ages between 2,200 and 1,800Ma (K23 and S1), an age gap of 1,800-1,000Ma for S1 and abundant Cadomian grains, indicate NW African/North Gondwanan derivation of these zircons. Also, A16 yields ages between 630 and 600Ma that can be attributed to "Pan-African” orogenic processes. Significant differences are seen for the <500Ma part of the age spectra with major age peaks at 493-494 and 344-335Ma (K23 and S1), and 477 and 287Ma (A16). All three samples show negative initial ɛHf signatures (−25 to −10, except one grain with +9.4) implying zircon crystallization from magmas derived by recycling of older continental crust. Hf isotopic compositions of 330- to 320-Ma-old zircons from S1 and K23 preclude a derivation from Bavarian Forest granites and intermediate granitoids. Rather, all the data suggest strong contributions of eroded local rocks (South Bohemian pluton, Gföhl unit) to loess material at the SE edge of the Bohemian Massif (K23 and S1) and sourcing of zircons from sediment donor regions in the Eastern Alps for loess at Wels (A16). We tentatively infer primary fluvial transport and secondary eolian reworking and re-deposition of detritus from western/southwestern directions. Finally, our data highlight that loess zircon ages are fundamentally influenced by fluvial transport, its directions, the interplay of sediment donor regions through the mixing of detritus and zircon fertility of rocks, rather than Paleowind directions. Springer-Verlag Berlin Heidelberg, 2015 Loess nationallicence Zircon nationallicence U‒Pb geochronology nationallicence Hf isotope geochemistry nationallicence Provenance nationallicence Újvári Gábor Geodetic and Geophysical Institute, MTA Research Centre for Astronomy and Earth Sciences, Csatkai E. u. 6-8, 9400, Sopron, Hungary aut Klötzli Urs Department of Lithospheric Research, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria aut International Journal of Earth Sciences Springer Berlin Heidelberg 104/5(2015-07-01), 1365-1385 1437-3254 104:5<1365 2015 104 531 https://doi.org/10.1007/s00531-014-1139-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00531-014-1139-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Újvári Gábor Geodetic and Geophysical Institute, MTA Research Centre for Astronomy and Earth Sciences, Csatkai E. u. 6-8, 9400, Sopron, Hungary aut NATIONALLICENCE 700 1- Klötzli Urs Department of Lithospheric Research, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria aut NATIONALLICENCE 773 0- International Journal of Earth Sciences Springer Berlin Heidelberg 104/5(2015-07-01), 1365-1385 1437-3254 104:5<1365 2015 104 531