Southern Region Chalk Group Lithostratigraphy: Bristow et al. (1997) - Tarrant Chalk

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The Tarrant Chalk , c. 30-40 m thick, is named after Tarrant valley near Blandford Forum, Dorset, and comprises firm, white chalk with large, relatively widely spaced flint bands, and rare marls (Bristow et al., 1997). A positive feature marks the base of the unit; it is stratigraphically variable in its position, but generally falls within the interval between the Meeching Marls and the Castle Hill Marls of Mortimore (1986a), in the upper part of the Newhaven Chalk of Mortimore (1986a) (Bristow et al., 1997). The top of the Tarrant Chalk is marked by a further positive feature, which biostratigraphical evidence suggests is close to the boundary of the Sompting and Whitecliff Beds of Mortimore (1986a). Thus the Tarrant Chalk equates with the highest Newhaven Chalk and lower Culver Chalk of Mortimore (1986a).

Macrofossil Biozonation: upper O. pilula Zone (locally), G. quadrata Zone (Hagenowia Horizon & A. cretaceus Subzone)

Correlation: see Correlation with other Southern Region successions

see Correlation with other UK successions

References[edit]

BRISTOW, C. R., MORTIMORE, R. N. & WOOD, C. J. 1997. Lithostratigraphy for mapping the Chalk of southern England. Proceedings of the Geologists' Association, Vol. 108, 293-315.

MORTIMORE, R N.1986a. Stratigraphy of the Upper Cretaceous White Chalk of Sussex. Proceedings of the Geologists' Association, Vol. 97(2), 97-139.

See: flint, marl, Newhaven Chalk (Mortimore, 1986a), Sompting Beds, Whitecliff Beds,Culver Chalk