Review of chrono-, litho- and biostratigraphy across the global Hangenberg Crisis and Devonian–Carboniferous Boundary

Abstract

Chrono-, litho- and biostratigraphy across the Devonian–Carboniferous transition are reviewed to provide a precise time framework for the global Hangenberg Crisis and for the current search for a revised basal Carboniferous Global Stratotype Section and Point (GSSP). The outer shelf deposits of the Rhenish Massif (Germany) form a lithological standard. Pre- (main Wocklum Limestone), lower (top Wocklum Limestone/Drewer Sandstone to Hangenberg Black Shale), middle (Hangenberg Shale/Sandstone), upper (Stockum Limestone), and post-crisis (Hangenberg Limestone) deposits are defined. Combined with the conodont, ammonoid and miospore zonations and eustatic trends, this succession can be correlated internationally. The contemporaneous successions of the Ardennes serve as a reference for shallow shelf settings. The positive and negative aspects of five options for a redefined Devonian–Carboniferous boundary level are discussed: (1) base of the black shale (main extinction level, base of Bispathodus costatus–Protognathodus kockeli Interregnum and LN Zone), (2) sequence boundary (widespread unconformities) or glacial and regressive peak (base of Hangenberg Sandstone), (3) base of the kockeli Zone and of initial postglacial transgression (base of lower Stockum Limestone), (4) entry of Siphonodella (Eosiphonodella) sulcata (base of upper Stockum Limestone), and (5) base of post-crisis interval (base of Hangenberg Limestone), at approximately the poorly correlated current GSSP level. Due to homonymy, Siphonodella (Siphonodella) hassi Ji, 1985 is renamed as Siphonodella (Siphonodella) jii nom. nov. Consequently, the mid-lower Tournaisian S. (S.) hassi Zone (previous Upper S. (S.) duplicata Zone) becomes the S. (S.) jii Zone.

The Kulm Facies of the Montagne Noire (Mississippian, southern France)

“…Due to problems with the index taxon (Siphonodella sulcata) and the facies of the stratotype section, the base of the Carboniferous is currently being revised and will likely be moved away from the La Serre section (e.g. Kaiser, 2005Kaiser, , 2009Kaiser & Corradini, 2011;Aretz, 2014;Becker et al, 2016).…”

Mississippian (Early Carboniferous) sequence stratigraphy of the Rhenish Kulm Basin, Germany

“…2). Along the northern margin of the RKB, a few metres thick, shale dominated unit is developed on top of the Hangenberg Limestone (Korn & Weyer, 2003, see also Becker et al, 2016). It is attributed to the FSST below the sequence boundary that separates the sharply overlying black alum shales of the Kahlenberg Fm (sequence 2; Fig.…”

“…The thorough and extensive reviews of Kaiser et al (2015) and Becker et al (2016) once more elucidated the global recognizable perturbations of the 'Sixth Phanerozoic Mass Extinction' during the Hangenberg crisis and concomitant sea-level changes at the 'end-Devonian sequence boundary' (Kaiser et al, 2015). Hence, it appears to be warrantable to place the base of sequence 1 at the base of the Hangenberg Sandstone.…”

“…The HST/FSST character of the Wocklum Limestone can be deduced e.g. from descriptions of Korn (1995), Becker (1996), Korn & Weyer (2003), and Becker et al, (2016) that noted increased faunal content and condensation close to its top. Moreover, the interpretation is compatible with the first influx of siliciclastics seen by the Drewer Sandstone in the uppermost Wocklum Limestone in the Drewer section Korn et al, 1994), and by increased Zr/Al values at the top of the Wocklum Limestone in other sections (Kumpan et al, 2015).…”

Conodont biostratigraphy and microfacies of the Late Devonian to Mississippian Milivojevića Kamenjar section (Družetić, NW Serbia)

“…This interval contains only one sample; it is thus named only tentatively, with the association indicate Upper duplicata Zone by Sandberg et al (1978) and Corradini (2003Corradini ( , 2008 [= jii Zone of Becker et al 2016, who renamed the previously introduced hassi Zone with the index fossil Si. (Si.)…”