Distinction between detrital and volcanogenic clay-rich beds in Turonian–Coniacian chalks of eastern England

SUMMARY null The acid insoluble null 2 O/A1 2 O 3 null ratio (mean 0.12), low Zr/Al 2 O 3 null ratio (mean 0.002) and variable TiO 2 /Al 2 O 3 null ratio (mean 0.07); shale normalized rare-earth element (REE) data displays a negative Ce anomaly and a variable, gradual depletion in heavy REE. By analogy with clays in the German Chalk, these beds are considered to be detrital. Six beds (Barton 1, Melton Ross, Deepdale Lower, North Ormsby, Ulceby...