Community replacement of neritic carbonate organisms during the late Valanginian platform demise: A new record from the Provence Platform

Depositional characteristics and constraints on the mid-Valanginian demise of a carbonate platform in the intra-Tethyan domain, Circum-Rhodope Belt, northern Greece

“…Sediments of the Circum-Rhodope carbonate platform display depositional characteristics that conform well to the outlined general models for Berriasian and Valanginian carbonate platforms from the Western Tethyan realm in terms of fossil assemblages, encrusting organisms, allochem composition, and microfacies types (Masse, 1993;Hillg€ artner, 1999;Shebl and Alsharhan, 2000;F€ ollmi et al, 2007;Koch et al, 2008;Krajewski, 2008;Gr eselle and Pittet, 2010;Jamalian et al, 2011;Krajewski et al, 2011;Bonin et al, 2012;Díaz de Neira and Gil-Gil, 2013). Thus, predominant skeletal sediments with diverse biota including boundstones with various microencrusters were formed along with considerable precipitation of lime muds and peloids.…”

“…However, the absence of other biota implies that the exclusive development of microbialites may have been related to short-lived mesotrophic levels due to enhanced continental runoff or upwelling of nutrient-rich water masses as was presumed for similar AptianeAlbian BacinellaeLithocodium-rich facies (Neuweiler and Reitner, 1992;Hillg€ artner et al, 2003;Immenhauser et al, 2005;Rameil et al, 2010;Huck et al, 2012). Alternatively, elevated seawater carbonate alkalinity and high seawater saturation state with respect to CaCO 3 due to intensified weathering of carbonate and silicate in the hinterland could have played important role in favoring the limited growth of BacinellaeLithocodium structures in an oligotrophic environment (Neuweiler and Reitner, 1992;Hillg€ artner et al, 2003; see also discussion in Bonin et al, 2012, and cited references).…”

“…4) of packstones and grainstones enriched in Crescentiella morronensis Crescenti (former Tubiphytes morronensis Crescenti, see Senowbari-Daryan et al, 2008). This organism having still disputed systematic position (Senowbari-Daryan et al, 2008) is considered as a typical microencruster of the mid-outer shelf and may occur in both shallow and deep water environments (Leinfelder et al, 1993;Schmid, 1996;Dupraz and Strasser, 1999;Senowbari-Daryan et al, 2008;Bonin et al, 2012;Kaya and Altiner, 2014). In this study, progressive shallowing of the marine setting relative to the underlying upper slope deposits, (MFT 3), can be interpreted on the basis of the following evidence: disappearance of calpionellids, calcareous dinocysts, Lenticulina foraminifera and brachiopods; presence of intraclasts and shallow marine fossil assemblage (bryozoans, echinoderms, thick-shelled bivalves, benthic foraminifera); common reworking of the bioclasts; minor amount of lime mud and predominance of grainstones.…”

“…A global mid-Valanginian perturbation of the carbon cycle recorded by a positive d 13 C excursion in marine carbonates and in terrestrial organic matter, so called Weissert event, was roughly concomitant with a salient crisis of carbonate-producing biota both in the neritic and pelagic domains Weissert and Erba, 2004;Gr€ ocke et al, 2005;Duchamp-Alphonse et al, 2007;Gr eselle et al, 2011;Barbarin et al, 2012). Several groups of benthic and planktonic organisms were severely affected during this earliest Cretaceous carbonate production crisis including bryozoans, rudists, foraminifera, dasycladacean algae, ammonites, belemnites, calpionellids, radiolarians, calcareous dinoflagellates and nannoconids (Reh akov a, 2000;O'Dogherty and Guex, 2002;Erba and Tremolada, 2004;Duchamp-Alphonse et al, 2007;F} ozy et al, 2010;Gr eselle et al, 2011;Barbarin et al, 2012;Bonin et al, 2012;F€ ollmi, 2012;Masse and Fenerci-Masse, 2013). While some groups Fig.…”

“…A global perturbation of the carbon cycle, so called Weissert event, was roughly concomitant with that crisis in pelagic and neritic carbonate production Duchamp-Alphonse et al, 2007;Gr eselle et al, 2011;Barbarin et al, 2012). Palaeoceanographical and palaeoenvironmental changes occurred at the early and late Valanginian boundary but their controls on the evolution of Western Tethyan carbonate platforms are still under discussion (Weissert and Erba, 2004;Gr eselle and Pittet, 2010;Bonin et al, 2012;F€ ollmi, 2012;F€ ollmi and Godet, 2013).…”