Carbon isotopes, palynology and stratigraphy of the Santonian–Campanian boundary: The GSSP auxiliary sections, Seaford Head (England) and Bocieniec (Poland), and correlation between the Boreal and Tethyan realms

The Global Boundary Stratotype Section and Point (GSSP) of the Campanian Stage at Bottaccione (Gubbio, Italy) and its Auxiliary Sections: Seaford Head (UK), Bocieniec (Poland), Postalm (Austria), Smoky Hill, Kansas (U.S.A), Tepayac (Mexico)

“…Pearce et al (2020) recorded the first occurrence of the species slightly higher in the upper Santonian (high U. socialis Zone) at the base of the Hawks Brow CIE in the type material from the Trunch borehole. More recent work on the Poigny 701 borehole (Pearce et al, 2022) confirms the first occurrence in the (low) U. socialis Zone immediately above the Buckle CIE (although due to the wide sampling interval, the event may occur closer to, or within, the Buckle CIE).…”

“…4). The isotope excursion can also be identified in chalks in Yorkshire, north-east England (Deville de Periere et al, 2019), in the Paris Basin (Chenot et al, 2016;Pearce et al, 2022), at Lägerdorf in northern Germany (Voigt et al, 2010), in marls at Bocieniec, Poland (Dubicka et al, 2017), and, critically, in the Global Stratotype section in the Scaglia Rossa in the Bottaccione Gorge at Gubbio, Umbria-Marche Basin, Italy (Fig. 4; see Thibault et al, 2016).…”

“…Gale (2018) described microcrinoid occurrences in the uppermost Santonian and lowest Campanian parts of the succession. Jarvis et al (2022) provided detailed palynological data and a high-resolution carbon isotope curve (Fig. 13).…”

“…However, it provides an excellent carbon-isotope curve which permits correlation of the crinoid zones to the Bottaccione GSSP section, and palynological data from the stage boundary interval at Seaford Head (Fig. 13) from Jarvis et al (2022).…”

“…A new palynological study of 40 samples (average ~1 m spacing) from Seaford Head was completed for this work, spanning the interval from the Buckle Flint (basal upper Santonian, U. socialis Zone) to the Old Nore Marl in the lower Campanian O. pilula Zone (Fig. 13; Jarvis et al, 2022). The floras are overwhelmingly dominated by organic walled dinoflagellate cysts (~90% of the total) with a moderate species richness of 30 to 64 taxa (average 43), although algae (particularly the prasinophyte Leiosphaeridia) are well represented in the Santonian.…”