Devonian/Carboniferous boundary glacioeustatic fluctuations in a platform-to-basin direction: A geochemical approach of sequence stratigraphy in pelagic settings

摘要: Abstract We investigated high-resolution stratigraphic distribution of selected major and trace elements gamma-ray spectra fourteen Devonian/Carboniferous (D/C) boundary sections Europe located in the late Palaeozoic Laurussia Gondwana. The aim was to geochemical signature a marked forced normal regressive interval which associated with rapid progradation siliciclastics into marine carbonate systems (Rhenish Massif) prominent hiatus shallow-water ramp settings (Namur–Dinant Basin). This represents Devonian Hangenberg event (HBE) sensu lato (middle praesulcata conodont zone) as defined by previous authors. (FSST LST) correlates thin shale layers (HBE shale) sandwiched between monotonous nodular calcilutite/calcisiltite successions at five pelagic Moravia, Carnic Alps, Montagne Noire, Pyrenees. In all continuous D/C sedimentation (i.e., except those Namur–Dinant Basin), HBE s.l. is accompanied elevated percentages detrital proxies (Al, K, Rb, Zr) changes their ratios (Zr/Rb, K/Al, Rb/K) are normally interpreted indicators increased siliciclastic input, provenance, grain size. Zr/Rb other traceable even without apparent lithological evidence can, therefore, facilitate correlation. Paleoredox productivity (U/Th Ni/Rb enrichment factors) only rarely show values black interval, indicating that water dysoxia/anoxia local rather than global phenomenon. Global correlations based on shales should therefore be dropped favor interval. Moreover, analysis rates upper expansa kockeli zone using published radiometric ages suggests time significant increase rate supply ocean, most distal sections. Consequently, interpretation condensed succession deposited during sea-level rise seems unlikely. interpret including record glacioeustatic drop aeolian transport connection climatic cooling glaciation. set markers related fluctuation can used for super-regional from platform basin settings. they current efforts determine new definition.