J 2016

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

BÁBEK, Ondřej, Tomáš KUMPAN, Jiří KALVODA a Tomáš MATYS GRYGAR

Základní údaje

Originální název

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

Autoři

BÁBEK, Ondřej (203 Česká republika, garant), Tomáš KUMPAN (203 Česká republika, domácí), Jiří KALVODA (203 Česká republika, domácí) a Tomáš MATYS GRYGAR (203 Česká republika)

Vydání

Sedimentary Geology, Elsevier Science, 2016, 0037-0738

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10500 1.5. Earth and related environmental sciences

Stát vydavatele

Nizozemské království

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 2.373

Kód RIV

RIV/00216224:14310/16:00087886

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000375736700008

Klíčová slova anglicky

Element geochemistry;Hangenberg event;Glacioeustasy;Devonian/Carboniferous boundary;Sedimentation rate;Pelagic carbonates

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 13. 3. 2018 13:18, Mgr. Tomáš Kumpan, Ph.D.

Anotace

V originále

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

Návaznosti

GA14-18183S, projekt VaV
Název: Sekvenční stratigrafie devonských bioeventů - výkyvy mořské hladiny na přechodu od klimatického režimu greenhouse k icehouse
Investor: Grantová agentura ČR, Sekvenční stratigrafie devonských bioeventů – výkyvy mořské hladiny na přechodu od klimatického režimu greenhouse k icehouse