Petrophysical and geochemical signature of the Hangenberg Events: an integrated stratigraphy of the Devonian-Carboniferous boundary interval in the Northern Rhenish Massif (Avalonia, Germany)

Bulletin of geosciences

Frýda J¹  Kalvoda J¹  Becker RT¹  Kumpan T¹  Hartenfels S¹  Bábek O¹  Matys Grygar T¹ 

关键词: Famennian;    Tournaisian;    Hangenberg Events;    gamma-ray spectrometry;    magnetic susceptibility;    element geochemistry;    stable carbon isotope geochemistry;   

DOI  :  

来源: Czech Geological Survey

【 摘 要 】

Petrophysical(gamma-rayspectrometry,magneticsusceptibility)andgeochemical(X-rayfluorescencespectrometryandinorganiccarbonisotopegeochemistry)methodsareusedforstratigraphiccorrelationsandpalaeoenvironmentalinterpretationsoftheDevonian-CarboniferousboundaryintervalinthenorthernpartoftheRheinischesSchiefergebirge,Germany.SectionsatOese,OberrodinghausenandDrewerwerestudiedinthestratigraphicrangefromtheFamennianUpperexpansaZonetotheTournaisianLowercrenulataZone.TheFamennianWocklumLimestonerevealsdistinctivecyclicityinthelimestoneandshalearrangement,whoseprimaryoriginhasbeensupportedbycorrelationwithK/Alratiochanges.Lower-orderK/Alcyclicityfollowsbundlesofalternatinglayers.Ontheotherhand,Zr/AlcyclicityisratherindependentonfaciesandK/AlanddurationofZr/Alcycleswasestimatedtobe370ka,whichiscloseto405kaeccentricity.CorrelationsofthecurvepatternsofComputedGammaRay,U/ThGRS,bulkmagneticsusceptibility,K/Al,Zr/Al,S,andMnproxieshavebeenemployedforregionalcorrelation.OurdatasetconfirmspreviouspalaeoenvironmentalinterpretationsoftheHangenbergEventsandadditionallyprovidesinformationongradualdecreaseinabottomoxygenationjustpriortheevents.Peaksinredoxandpalaeoproductivityproxies(U/Th,Cu+Ni+Zn+Pb)occurintheHangenbergBlackShaleinallstudiedsections.AlthoughsedimentationoftheHangenbergBlackShaletookplaceduringthedeepeningstep,theenhancedpalaeoproductivityandhypoxiatoanoxiawerethemaincauseofitsdeposition.AninterregionalcorrelationoftheDevonian-CarboniferousintervalsfromthenorthernRhenishMassif,MoravianKarstandCarnicAlpswascarriedoutandunderlinesthepotentialforfurtherchronostratigraphicdefinitions.

【 授权许可】

Unknown