Southern Region Chalk Group Lithostratigraphy: Sussex lithostratigraphy of Mortimore (1986a) - Glynde Beds

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The Glynde Beds, c. 11m thick at the stratotype locality at the Glynde Pit [TQ 4497 0956] near Lewes (Lake et al., 1987), equate with the interval between the lowest of the Glynde Marls (at the base) to the base of Southerham Marl 1, at the top. The lowest (most conspicuous) of the Glynde Marls is black and plastic textured, and overlain by a further three to five thin marls, in smooth-textured chalk (Mortimore, 1986a). Higher in the Glynde Beds is the appearance of hard, nodular, iron-stained chalk, with the first regularly developed flint horizons in the Chalk Group (Mortimore, 1986a). A conspicuous bed of nodular flints, just below the top of the Glynde Beds, is named the Southerham Flints (Mortimore, 1986a).

The fauna of the Glynde Beds is dominated by brachiopods, especially large terebratulids and the small Terebratulina lata; the inoceramid bivalve Inoceramus cuvieri is abundant, and the echinoids Micraster corbovis and Sternotaxis plana also occur (Mortimore, 1986a).

Macrofossil Biozonation: upper T. lata Zone

Correlation: see Correlation with other Southern Region Chalk Group classifications

see Correlation with other UK Chalk Group successions

References[edit]

LAKE, R D, YOUNG, B, WOOD, C J & MORTIMORE, R N. 1987. Geology of the country around Lewes. Memoir of the British Geological Survey.

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

See: marl, nodular chalk, hardground, Southerham Flints