Ammonoids and Quantitative Biochronology—A Unitary Association Perspective

High-resolution biochronology and diversity dynamics of the Early Triassic ammonoid recovery: The Dienerian faunas of the Northern Indian Margin

“…A general account of the advantages of this method is given in Brühwiler et al (2010b), and for the exhaustive description of the UA method the reader is referred to Guex (1991), Monnet and Bucher (2002) and Monnet et al (2015). The UA analysis was performed with the palaeontological data analysis software PAST (Hammer et al, 2001).…”

Ammonite Biostratigraphy of the Cretaceous—An Overview

“…Modern time scales favor a holistic approach of integrating geological time, based on absolute age dating with a set of stratigraphic tools (Ogg et al 2004;2012). Ammonite zones are in fact a central component of current time scales (Gradstein et al 2012), but there are several pitfalls: (1) most zones can be valid for certain regions of the world only, (2) integrating biozones is based on different methodological approaches (total range zones, assemblage zones etc., see above; compare Monnet et al 2015a), and last but not least, (3) in many cases time might be hidden in stratigraphic gaps rather than in the sedimentary record (e.g., Einsele 2000). Thus time is not continuously represented by the biozones, but might be hidden in sedimentary discontinuities within the sequence or at zonal boundaries.…”

“…In quantitative stratigraphic methods (see Monnet et al 2015a for a review), like graphic correlation (Miller 1977;Hammer and Harper 2005), LOs and FOs of Cretaceous ammonites are also used as basic data. Graphic correlation is rarely based on ammonite data alone, since the combination of different types of stratigraphic data has proven to be the most successful (e.g., Immenhauser et al 2000;Oboh-Ikuenobe et al 2007;Scott 2009).…”

Ammonoid Biostratigraphy in the Jurassic

“…Apart from methods of quantitative stratigraphy (see Monnet et al 2015a for a review), numerous other methods (e.g., magnetostratigraphy, sequence stratigraphy, cyclostratigraphy, geochemical and isotopic data, radiometric dating) and biostratigraphic studies of other groups (dinoflagellates, radiolarians, pollen and spores) provide additional data for calibrations and refinements of the Jurassic standard time scale (e.g., Sadler 2004, Palfy 2007, Ogg and Hinnov 2012. These additional methods may help in dating Jurassic sediments even when there are no ammonoids available, like in terrestrial deposits.…”